Jo Kramer-Johansen

• Isern, Cecilie Benedicte; Bahr, Roald; Flønes, Malin; Jorstad, Harald; Kramer-Johansen, Jo & Mjøs, Ingrid [Show all 8 contributors for this article] (2025). Out-of-hospital cardiac arrest in Norwegians aged 12–49 years: nationwide analysis of preceding symptoms and risk factors related to aetiology and pre-arrest exercise habits. BMJ Open sport & exercise medicine. 11, p. 1–12. doi: 10.1136/bmjsem-2025-002505. Full text in Research Archive Show summary

  Background Out-of-hospital cardiac arrest (OHCA) in the young is a tragic event. Regular exercise reduces cardiovascular disease (CVD) risk but, at certain intensities and volumes, is associated with increased OHCA risk. Understanding symptoms, risk factors and aetiology is central for primary prevention. Objective Assess symptoms and risk factors related to OHCA aetiology in young Norwegians, and the role of exercise volume. Method We obtained data from the Norwegian Cardiac Arrest Registry (2015–2017), medical records, autopsy reports and questionnaires. Inclusion criteria were ages 12–49 years and OHCA of presumed cardiac aetiology. Results Data from 134 individuals (81 survivors, 53 deceased) showed that CVD symptoms were present during both rest/everyday activity and exercise in most victims, and were reported by more survivors than by next-of-kin of the deceased (78% vs 60%). Only 12% had symptoms just during exercise. Ischaemic heart disease was the leading cause (58% in males vs 38% in females), followed by structural, non-ischaemic heart disease. Sudden unexpected death syndrome (SUDS) was most common in individuals aged ≤35 years. Risk factors were present in 74%, with family history for CVD most prevalent (51%) and overweight in at least 33%. There were no significant differences in symptoms, risk factors or OHCA aetiology related to exercise volume prior to OHCA. Conclusion Symptoms and CVD risk factors were prevalent in young Norwegians suffering OHCA regardless of exercise volume. Ischaemic heart disease was the leading cause of OHCA. We suggest evaluating symptoms carefully and addressing risk factors to prevent OHCA in young Norwegians regardless of exercise habits.

• Kjær, Jeannett; Milling, Louise; Brøchner, Anne Craveiro; Lippert, Freddy; Blomberg, Stig Nikolaj & Christensen, Helle Collatz [Show all 187 contributors for this article] (2025). Prehospital cardiac arrest resuscitation practices differ around the globe. Resuscitation Plus. 25, p. 1–7. doi: 10.1016/j.resplu.2025.101017. Full text in Research Archive
• Tjelmeland, Ingvild Beathe Myrhaugen; Alm-Kruse, Kristin; Andersson, Lars-Jøran; Larsen, Alf Inge; Lindner, Thomas Werner & Olasveengen, Theresa M. [Show all 7 contributors for this article] (2025). Patient cohorts of interest in resuscitation science – Aligning cardiac arrest registry outputs with stakeholder needs. Resuscitation. ISSN 0300-9572. 210. doi: 10.1016/j.resuscitation.2025.110509. Full text in Research Archive Show summary

  Introduction: Cardiac arrest registries can benchmark, enhance quality of care and provide data for research. Key stakeholders from Emergency Medical Communication Centre (EMCC), Emergency Medical Services (EMS), In-Hospital Care Providers (IHCP) and Recovery and Rehabilitation Providers (RRP) have different perspectives, and registry results and patient cohorts should be tailored to facilitate benchmarking, quality improvement projects and research in all sections of the chain of survival. In this paper, we describe different cohorts of interest, exemplified by data from the Norwegian Cardiac Arrest Registry (NorCAR). Method: Data from NorCAR for patients registered in 2022 is presented as descriptive statistics. Results: The patient cohort with treatment initiated by EMCC comprised 3591 patients (67/100,000 inhabitants). EMS attended 4150 patients with confirmed cardiac arrest (77/100,000 inhabitants) and started cardiopulmonary resuscitation (CPR) in 3083 patients (57/100,000 inhabitants). The patient cohort eligible for treatment by IHCP consists of 1114 patients admitted to hospital alive or with ongoing CPR, along with 1230 in-hospital cardiac arrest cases. The cohort eligible for rehabilitation and follow-up consists of 1227 patients who were alive 24 h after cardiac arrest, 705 out-of-hospital cardiac arrests and 522 in-hospital cardiac arrests. Conclusion: It is essential to clearly define the cohort of interest when engaging with different stakeholders and to provide data that facilitates quality improvement projects in all areas of the chain of survival. We recommend defining several subgroups of cardiac arrest patients to accommodate benchmarking, quality improvement projects and research relevant for all stakeholders involved in resuscitation and care of cardiac arrest patients.

• Idland, Siri; Häikiö, Kristin; Kramer-Johansen, Jo & Hjortdahl, Magnus (2025). “They were sort of in the room with me”: a qualitative study about callers’ experience of video streaming during medical emergency calls. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. doi: 10.1186/s13049-024-01317-8. Full text in Research Archive Show summary

  Background During the recent years, emergency services in several countries have integrated video streaming into medical emergency calls, and research on the topic has gained increased focus. Video streaming during medical emergency calls may change dispatcher’s perspective of the call and can be a helpful tool for supervising bystanders’ first aid. Little research exists, however, about the caller’s perspective of video streaming during a medical emergency call. With this study, we explore the caller’s experiences with video streaming.<p> <p>Methods The study is a qualitative interview study. During a period of five weeks, we recruited respondents from the region of Oslo who had called the medical emergency number 113 and where video streaming had been used by the dispatcher during the call. We conducted 14 semi-structured individual interviews, in-person or digitally on Zoom/Teams, from October to December 2023. The interviews were transcribed verbatim, and we analyzed them drawing on Malterud’s systematic text condensation. <p>Results Our material was sorted into three category headings: Increased sense of safety, the unexpected option of video streaming, and emotional discomfort. Most respondents felt comforted knowing that the dispatcher could see and assess the situation visually. Several were also positively surprised that video streaming was an option during the call. Some respondents however felt increased stress during the call due to video streaming. Other respondents reflected on the societal taboo of filming ill or injured persons. <p>Conclusion Most respondents experienced video streaming as a positive addition to the medical emergency call and felt comforted knowing that the dispatcher could see the situation. Knowledge of the integration between video streaming and basic communication in a call is nonetheless of great importance, as to not increase stress experienced by the caller. The dispatcher should be sensitive for how the caller will handle video streaming for each call.

• Steenstrup, Sophie; Kramer-Johansen, Jo & Berge, Hilde Moseby (2025). Saving lives together in sport: − A pilot study attempting to increase the number and availability of automated external defibrillators and to initiate voluntary training in cardiopulmonary resuscitation with the use of automated external defibrillators in Norwegian amateur football clubs. Resuscitation. ISSN 0300-9572. 209. doi: 10.1016/j.resuscitation.2025.110586. Full text in Research Archive Show summary

  Objectives In Norway, the potential to increase the number of patients connected to an automated external defibrillator (AED) before ambulance arrival in out-of-hospital cardiac arrests is substantial. A blended learning approach is effective for cardiopulmonary resuscitation (CPR) training with AED usage, and regular hands-on CPR refresher training is recommended. The objective was to test if provision of CPR-training equipment and learning resources combined with a contract to recruit volunteer CPR trainers could facilitate regular refresher CPR-training in Norwegian football clubs and to increase the number and accessibility of AEDs by providing clubs with AEDs and heated cabinets and mandate registration in the national AED registry. Methods Non-randomized pilot study (2020–2023). Clubs signed contracts that they would perform CPR training with the use of AEDs for 70% of football players/coaches/staff/volunteers each year and place their received AED outdoors in heated cabinets and register their AED in the Norwegian national AED registry. We explored barriers through follow-up e-mails. Results We recruited 116 of 278 (42%) eligible football clubs. From 2020 to 2023, 5440 football players and 987 coaches/staff/volunteers from 60 (52%) clubs completed CPR training sessions and 20 (17%) repeated CPR training. We provided 112 AEDs and 116 heated cabinets. By a deadline, 68/116 (59%) of clubs had placed their AED outdoors in the heated cabinet and registered their AED correctly in the national AED registry, 27/116 (23%) placed their AED outdoors but did not complete their registration in the AED registry correctly, 13/116 (11%) kept their AED locked indoors and 8/116 (7%) failed to register their AED. Few clubs (20/116, 17%) provided insights into barriers. Conclusion We recruited a satisfactory number of football clubs. Over 6000 players/coaches/staff/volunteers completing CRP training shows promise. Most clubs complied to the message of 24/7/365 availability of AEDs and found registration in the national AED registry uncomplicated.

• Idland, Siri; Kramer-Johansen, Jo; Bakke, Håkon Kvåle; Småstuen, Milada Cvancarova; Tønsager, Kristin & Platou, Hans-Christian Stoud [Show all 7 contributors for this article] (2024). Can video streaming improve first aid for injured patients? A prospective observational study from Norway. BMC Emergency Medicine. 24(1). doi: 10.1186/s12873-024-01010-0. Full text in Research Archive Show summary

  Background - Video streaming in emergency medical communication centers (EMCC) from caller to medical dispatcher has recently been introduced in some countries. Death by trauma is a leading cause of death and injuries are a frequent reason to contact EMCC. We aimed to investigate if video streaming is associated with recognition of a need for first aid during calls regarding injured patients and improve quality of bystander first aid.<p> <p>Methods - A prospective observational study including patients from three health regions in Norway, from November 2021 to February 2023 (registered in clinical trials 10/25/2021, NCT05121649). Cases where video streaming had been used as a supplement during the medical emergency call were compared to cases where video streaming was not used during the call. Patients were included by ambulance personnel on the scene of accident if they met the following criteria: 1. Ambulance personnel arrived at a patient who had an injury, 2. One or more bystanders had been present before their arrival, 3. One or more of the following first aid measures had been performed by bystander or should have been performed: airway management, control of external bleeding, recovery position, and hypothermia prevention. Ambulance personnel assessed quality of first aid performed by bystander, and information concerning use of video streaming and patient need for first aid measures recognized by dispatcher was collected through EMCC audio logs and patient charts. We present descriptive data and results from a logistic regression analysis.<p> <p>Results - Data was collected on 113 cases, and dispatchers used video streaming in addition to standard telephone communication in 12/113 (10%) of the cases. The odds for the dispatcher to recognize a need for first aid during a medical emergency call were more than five times higher when video streaming was used compared to no use of video streaming (OR 5.30, 95% CI 1.11-25.44). Overall quality of bystander first aid was rated as “high”. The odds ratio for the patient receiving first aid of higher quality were 1.82 (p-value 0.46) when video streaming was used by dispatcher during the call.<p> <p>Conclusion - Our findings show that video streaming is not frequently used by dispatchers in calls regarding patients with injuries, but that video streaming is associated with improved recognition of patients’ first aid needs. We found no statistically significant difference in first aid quality comparing the calls where video streaming as a supplement were used with the calls with audio only.

• Alm-Kruse, Kristin; Gjerset, Gunhild M.; Tjelmeland, Ingvild B. M.; Isern, Cecilie B.; Kramer-Johansen, Jo & Garratt, Andrew M. (2024). How do survivors after out-of-hospital cardiac arrest perceive their health compared to the norm population? A nationwide registry study from Norway. Resuscitation Plus. 17. doi: 10.1016/j.resplu.2023.100549. Full text in Research Archive Show summary

  Introduction: Self-perceived health status data is usually collected using patient-reported outcome measures. Information from the patients’ perspective is one of the important components in planning person-centred care. The study aimed to compare EQ-5D-5L in survivors after out-of-hospital cardiac arrest (OHCA) with data for Norwegian population controls. Secondary aim included comparing characteristics of respondents and non-respondents from the OHCA population. Methods: In this cross-sectional survey, 714 OHCA survivors received an electronic EQ-5D-5L questionnaire 3–6 months following OHCA. EQ-5D-5L assesses for five dimensions of health (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression) with five-point descriptive scales and overall health on a visual analogue scale from 0 (worst) to 100 (best) (EQ VAS). Results are used to calculate the EQ index ranging from −0.59 (worst) to 1 (best). Patient responses were matched for age and sex with existing data from controls, collected through a postal survey (response rate 26%), and compared with Chi-square tests or t-tests as appropriate. Results: Of 784 OHCA survivors, 714 received the EQ-5D-5L, and 445 (62%) responded. Respondents had higher rates of shockable first rhythm and better cerebral performance category scores than the non-respondents. OHCA survivors reported poorer health compared to controls as assessed by EQ-5D-5L dimensions, the EQ index (0.76 ± 0.24 vs 0.82 ± 0.18), and EQ VAS (69 ± 21 vs 79 ± 17), except for the pain/discomfort dimension. Conclusions: Norwegian OHCA survivors reported poorer health than the general population as assessed by the EQ-5D-5L. PROMs use in this population can be used to inform follow-up and health care delivery.

• Jamtli, Bjørn; Svendsen, Edel Jannecke; Jørgensen, Trine Møgster; Kramer-Johansen, Jo; Hov, Maren Ranhoff & Hardeland, Camilla (2024). Factors affecting emergency medical dispatchers decision making in stroke calls – a qualitative study. BMC Emergency Medicine. 24(1), p. 214–214. doi: 10.1186/s12873-024-01129-0. Full text in Research Archive Show summary

  Objectives Emergency Medical Communication Centers (EMCC) have a key role in the prehospital chain-of-stroke-survival by recognizing stroke patients and reducing prehospital delay. However, studies on EMCC stroke recognition report both substantial undertriage and overtriage. Since mis-triage at the EMCC challenges the whole chain-of-stroke-survival, by occupying limited resources for non-stroke patients or failing to recognize the true stroke patients, there is a need to achieve a more comprehensive understanding of the dispatchers’ routines and experiences. The aim of this study was to explore factors affecting EMCC dispatcher’s decision-making in stroke calls. Materials and methods A qualitative exploratory study, based on individual semi-structured interviews of 15 medical dispatchers from EMCC Oslo, Norway. Interviews were conducted during August and October 2022 and analyzed using the principles of thematic analysis. Results We identified four themes: [1] Pronounced stroke symptoms are easy to identify [2]. Non-specific neurological symptoms raise suspicion of acute stroke but are difficult to differentiate from other medical conditions [3]. Consistent use of the Criteria Based Dispatch (CBD) protocol may increase EMCC overtriage [4]. Contextual conditions at EMCC can affect dispatchers’ decision-making process and the ability for experiential learning. Conclusions Medical dispatchers at the EMCC perceive vague and non-specific stroke symptoms, such as dizziness, confusion or altered behaviour, challenging to differentiate from symptoms of other less time-critical medical conditions. They also perceive the current CBD protocol in use as less supportive in assessing such symptoms. High workload and strict EMCC response time interval requirements hinder the gathering of essential patient information and the ability to seek guidance in cases of doubt, potentially exacerbating both EMCC undertriage and overtriage. The absence of feedback loops and other strategies for experiential learning in the EMCC hampers the medical dispatcher’s ability to evaluate their own assessments and improve dispatch accuracy.

• Katzenschlager, Stephan; Elshaer, Ahmed; Metelmann, Bibiana; Metelmann, Camilla; Thilakasiri, Kaushila & Karageorgos, Vlasios [Show all 12 contributors for this article] (2024). Top 5 barriers in cardiac arrest research as perceived by international early career researchers – A consensus study. Resuscitation Plus. 18. doi: 10.1016/j.resplu.2024.100608. Full text in Research Archive Show summary

  Aim of the study Cardiac arrest research has not received as much scientific attention as research on other topics. Here, we aimed to identify cardiac arrest research barriers from the perspective of an international group of early career researchers. Methods Attendees of the 2022 international masterclass on cardiac arrest registry research accompanied the Global Out-of-Hospital Cardiac Arrest Registry collaborative meeting in Utstein, Norway, and used an adapted hybrid nominal group technique to obtain a diverse and comprehensive perspective. Barriers were identified using a web-based questionnaire and discussed and ranked during an in-person follow-up meeting. After each response was discussed and clarified, barriers were categorized and ranked over two rounds. Each participant scored these from 1 (least significant) to 5 (most significant). Results Nine participants generated 36 responses, forming seven overall categories of cardiac arrest research barriers. “Allocated research time” was ranked first in both rounds. “Scientific environment”, including appropriate mentorship and support systems, ranked second in the final ranking. “Resources”, including funding and infrastructure, ranked third. “Access to and availability of cardiac arrest research data” was the fourth-ranked barrier. This included data from the cardiac arrest registries, medical devices, and clinical studies. Finally, “uniqueness” was the fifth-ranked barrier. This included ethical issues, patient recruitment challenges, and unique characteristics of cardiac arrest. Conclusion By identifying cardiac arrest research barriers and suggesting solutions, this study may act as a tool for stakeholders to focus on helping early career researchers overcome these barriers, thus paving the road for future research.

• Jamtli, Bjørn; Hov, Maren Ranhoff; Jørgensen, Trine Møgster; Kramer-Johansen, Jo; Ihle-Hansen, Hege Beate & Sandset, Else Charlotte [Show all 8 contributors for this article] (2024). Telephone triage and dispatch of ambulances to patients with suspected and verified acute stroke - a descriptive study. BMC Emergency Medicine. 24(1). doi: 10.1186/s12873-024-00962-7. Full text in Research Archive Show summary

  Objectives In this study we aimed to explore EMCC triage of suspected and confirmed stroke patients to gain more knowledge about the initial phase of the acute stroke response chain. Accurate dispatch at the Emergency Medical Communication Center (EMCC) is crucial for optimal resource utilization in the prehospital service, and early identification of acute stroke is known to improve patient outcome. Materials and methods We conducted a descriptive retrospective study based on data from the Emergency Department and EMCC records at a comprehensive stroke center in Oslo, Norway, during a six-month period (2019–2020). Patients dispatched with EMCC stroke criteria and/or discharged with a stroke diagnosis were included. We identified EMCC true positive, false positive and false negative stroke patients and estimated EMCC stroke sensitivity and positive predictive value (PPV). Furthermore, we analyzed prehospital time intervals and identified patient destinations to gain knowledge on ambulance services assessments. Results We included 1298 patients. EMCC stroke sensitivity was 77% (95% CI: 72 − 82%), and PPV was 16% (95% CI: 14 − 18%). EMCC false negative stroke patients experienced an increased median prehospital delay of 11 min (p < 0.001). Upon arrival at the scene, 68% of the EMCC false negative patients were identified as suspected stroke cases by the ambulance services. Similarly, 68% of the false positive stroke patients were either referred to a GP, out-of-hours GP acute clinic, local hospitals or left at the scene by the ambulance services, indicating that no obvious stroke symptoms were identified by ambulance personnel upon arrival at the scene. Conclusions This study reveals a high EMCC stroke sensitivity and an extensive number of false positive stroke dispatches. By comparing the assessments made by both the EMCC and the ambulance service, we have identified specific patient groups that should be the focus for future research efforts aimed at improving the sensitivity and specificity of stroke recognition in the EMCC.

• Kelpanides, Inga Katherina; Katzenschlager, Stephan; Skogvoll, Eirik; Tjelmeland, Ingvild Beathe Myrhaugen; Berner, Guro Grindheim & Alm-Kruse, Kristin [Show all 11 contributors for this article] (2024). Out-of-hospital cardiac arrest in children in Norway: A national cohort study, 2016–2021. Resuscitation Plus. 18. doi: 10.1016/j.resplu.2024.100662. Full text in Research Archive Show summary

  Aim Children constitute an important and distinct subgroup of out-of-hospital cardiac arrest (OHCA) patients. This population-based cohort study aims to establish current age-specific population incidence, precipitating causes, circumstances, and outcome of paediatric OHCA, to guide a focused approach to prevention and intervention to improve outcomes. Methods Data from the national Norwegian Cardiac Arrest Registry was extracted for the six-year period 2016–21 for persons aged <18 years. We present descriptive statistics for the population, resuscitation events, presumed causes, treatment, and outcomes, alongside age-specific incidence and total paediatric mortality rates. Results Three hundred and eight children were included. The incidence of OHCA was 4.6 per 100 000 child-years and markedly higher in children <1 year at 20.9 child-years. Leading causes were choking, cardiac and respiratory disease, and sudden infant death syndrome. Overall, 21% survived to 30 days and 18% to one year. Conclusion A registry-based approach enabled this study to delineate the characteristics and trajectories of OHCA events in a national cohort of children. Precipitating causes of paediatric OHCA are diverse compared to adults. Infants aged <1 year are at particularly high risk. Mortality is high, albeit lower than for adults in Norway. A rational community approach to prevention and treatment may focus on general infant care, immediate first aid by caretakers, and identification of vulnerable children by primary health providers. Cardiac arrest registries are a key source of knowledge essential for quality improvement and research into cardiac arrest in childhood.

• Tjelmeland, Ingvild Beathe Myrhaugen; Alm-Kruse, Kristin; Svensøy, Johannes Nordsteien; Landbø, Gry & Kramer-Johansen, Jo (2023). Norsk hjertestansregister. Norsk Epidemiologi. ISSN 0803-2491. 31(1-2), p. 25–30. doi: 10.5324/nje.v31i1-2.5607. Full text in Research Archive
• Eftestøl, Trygve Christian; Hognestad, Mari; Søndeland, Sander A.; Rad, Ali Bahrami; Aramendi, Elisabete & Wik, Lars [Show all 7 contributors for this article] (2023). A Convolutional Neural Network Approach for Interpreting Cardiac Rhythms from Resuscitation of Cardiac Arrest Patients. Computing in cardiology. ISSN 2325-8861. 50. doi: 10.22489/CinC.2023.304. Full text in Research Archive
• Bjørshol, Conrad Arnfinn; Nordseth, Trond & Kramer-Johansen, Jo (2023). Why the Norwegian 2021 guideline for basic life support are different. Resuscitation Plus. 14. doi: 10.1016/j.resplu.2023.100392. Full text in Research Archive Show summary

  Medical guidelines provide health care professionals with a framework for how they should treat patients and perform training. Although based on the available scientific evidence, their legitimacy depends on a transparent process for development and implementation. In the absence of sufficient evidence, consensus processes can be guided by values and preferences.1 In cardiac arrest, death is imminent unless a chain of actions is initiated within minutes.2 Therefore, guidelines for cardiopulmonary resuscitation (CPR) have existed for more than six decades.3 Time-critical actions like CPR,4 defibrillation5 and notification of emergency medical services (EMS),6 have improved outcomes for a large number of patients with out-of-hospital cardiac arrest (OHCA).

• Idland, Siri; Kramer-Johansen, Jo; Bakke, Håkon Kvåle & Hjortdahl, Magnus (2023). Assessing bystander first aid: development and validation of a First Aid Quality Assessment (FAQA) tool. BMC Emergency Medicine. doi: 10.1186/s12873-023-00811-z. Full text in Research Archive Show summary

  Background Injuries are one of the leading causes of death worldwide. Bystanders at the scene can perform first aid measures before the arrival of health services. The quality of first aid measures likely affects patient outcome. However, scientifc evidence on its efect on patient outcome is limited. To properly assess bystander first aid quality, measure effect, and facilitate improvement, validated assessment tools are needed. The purpose of this study was to develop and validate a First Aid Quality Assessment (FAQA) tool. The FAQA tool focuses on first aid measures for injured patients based on the ABC-principle, as assessed by ambulance personnel arriving on scene.<p> <p>Methods In phase 1, we drafted an initial version of the FAQA tool for assessment of airway management, control of external bleeding, recovery position and hypothermia prevention. A group of ambulance personnel aided presenta‑ tion and wording of the tool. In phase 2 we made eight virtual reality (VR) films, each presenting an injury scenario where bystander performed frst aid. In phase 3, an expert group discussed until consensus on how the FAQA tool should rate each scenario. Followingly, 19 respondents, all ambulance personnel, rated the eight films with the FAQA tool. We assessed concurrent validity and inter-rater agreement by visual inspection and Kendall’s coefficient of concordance. <p>Results FAQA-scores by the expert group concurred with±1 of the median of the respondents on all first aid meas‑ ures for all eight films except one case, where a deviation of 2 was seen. The inter-rater agreement was “very good” for three first aid measures, “good” for one, and “moderate” for the scoring of overall quality on first aid measures. <p>Conclusion Our findings show that it is feasible and acceptable for ambulance personnel to collect information on bystander first aid with the FAQA tool and will be of importance for future research on bystander first aid for injured patients.

• Andresen, Åke Erling Lappen; Lauritzen, Magnus Varlid; Kramer-Johansen, Jo & Kristiansen, Thomas (2023). Implementation and use of a supraglottic airway device in the management of out-of-hospital cardiac arrest by firefighter first responders – A prospective feasibility study. Resuscitation Plus. 16. doi: 10.1016/j.resplu.2023.100480. Full text in Research Archive Show summary

  Aim We wanted to assess the implementation and use of a supraglottic airway (SGA) for on-call firefighter first responders in out-of-hospital cardiac arrest. Methods We trained 502 firefighter first responders, located at 35 fire stations in the South-East of Norway, in the use of SGA during cardiopulmonary resuscitation in adult out-of-hospital cardiac arrest. Training consisted of 45 minutes of theoretical and practical training in small groups. Primary outcome was successful ventilation with SGA assessed by both firefighter first responders and first paramedic arriving on-scene. Secondary outcomes included time expenditure and complications related to the procedure, evaluation of the training, and descriptive characteristics of the out-of-hospital cardiac arrest cases. Results An SGA was used by firefighter first responders in 23 out-of-hospital cardiac arrests, and successful ventilation was achieved in 20 (87%) cases. Air-leak was described in the three unsuccessful cases. The median procedural time was 30 seconds (IQR = 15–40), with no observed procedural complications. Firefighter first responders arrived in median time 9 minutes (IQR = 6–10 min) before the ambulance. They performed chest compressions on all patients and 6 (26%) of the patients received shock with semi-automatic external defibrillator. After training, all participants were able to successfully ventilate a manikin with the SGA. The cost of the SGA equipment for all fire stations was 3955 GBP. Conclusion Implementation of an SGA for firefighter first responders in out-of-hospital cardiac arrest management seems feasible, safe and can be introduced with limited amount of training and limited use of resources.

• Harring, Astrid Karina V.; Kramer-Johansen, Jo & Tjelmeland, Ingvild Beathe Myrhaugen (2023). Resuscitation of older adults in Norway; a comparison of survival and outcome after out-of-hospital cardiac arrest in healthcare institutions and at home. Resuscitation. ISSN 0300-9572. 189. doi: 10.1016/j.resuscitation.2023.109871. Full text in Research Archive Show summary

  Background Perceptions about expected outcome after out-of-hospital cardiac arrest (OHCA) influence treatment decisions, and there is a need for updated evidence about outcomes for the elderly. Method We conducted a cross-sectional study of cases reported to the Norwegian Cardiac Arrest Registry from 2015 through 2021 of patients 60 years and older, suffering cardiac arrest in healthcare institutions or at home. We examined reasons for emergency medical service (EMS) withholding or withdrawing resuscitation. We compared survival and neurological outcome for EMS-treated patients and explored factors associated with survival using multivariate logistic regression. Result We included 12,191 cases and the EMS started resuscitation in 10,340 (85%). The incidence per capita of OHCA the EMS were alerted to was 267/100,000 in healthcare institutions and 134/100,000 at home. Resuscitation was most frequently withdrawn due to medical history (n = 1251). In healthcare institutions, 72 of 1503 (4.8%) patients survived to 30 days compared to 752 of 8837 (8.5%) at home (P <.001). We found survivors in all age cohorts both in healthcare institutions and at home, and most of the 824 survivors had a good neurological outcome with a Cerebral Performance Category ≤2 (88%). Conclusion Medical history was the most frequent reason for EMS not to start or continue resuscitation, indicating a need for a discussion about, and documentation of, advance directives in this age group. When EMS attempted resuscitation, most survivors had a good neurological outcome, both in healthcare institutions and at home.

• Tjelmeland, Ingvild Beathe Myrhaugen; Wnent, Jan; Masterson, Siobhan; Kramer-Johansen, Jo; Ong, Marcus Eng Hock & Smith, Karen [Show all 14 contributors for this article] (2023). Did lockdown influence bystanders’ willingness to perform cardiopulmonary resuscitation? A worldwide registry-based perspective. Resuscitation. ISSN 0300-9572. doi: 10.1016/j.resuscitation.2023.109764. Full text in Research Archive Show summary

  Aim Bystander cardiopulmonary resuscitation (CPR) significantly increases the survival rate after out-of-hospital cardiac arrest. Using population-based registries, we investigated the impact of lockdown due to Covid-19 on the provision of bystander CPR, taking background changes over time into consideration. Methods Using a registry network, we invited all registries capable of delivering data from 1. January 2017 to 31. December 2020 to participate in this study. We used negative binominal regression for the analysis of the overall results. We also calculated the rates for bystander CPR. For every participating registry, we analysed the incidence per 100 000 inhabitants of bystander CPR and EMS-treated patients using Poisson regression, including time trends. Results Twenty-six established OHCA registries reported 742 923 cardiac arrest patients over a four-year period covering 1.3 billion person-years. We found large variations in the reported incidence between and within continents. There was an increase in the incidence of bystander CPR of almost 5% per year. The lockdown in March/April 2020 did not impact this trend. The increase in the rate of bystander CPR was also seen when analysing data on a continental level. We found large variations in incidence of bystander CPR before and after lockdown when analysing data on a registry level. Conclusion There was a steady increase in bystander CPR from 2017 to 2020, not associated with an increase in the number of ambulance-treated cardiac arrest patients. We did not find an association between lockdown and bystanders’ willingness to start CPR before ambulance arrival, but we found inconsistent patterns of changes between registries.

• Alm-Kruse, Kristin; Tjelmeland, Ingvild Beathe Myrhaugen; Reiner, Andrew Henry; Kvåle, Rune & Kramer-Johansen, Jo (2023). Use of healthcare services before and after out-of-hospital cardiac arrest. Resuscitation. ISSN 0300-9572. 187. doi: 10.1016/j.resuscitation.2023.109805. Full text in Research Archive Show summary

  Introduction Knowledge about the use of healthcare services in patients experiencing out-of-hospital cardiac arrest (OHCA) is limited. We aimed to describe and compare the use of healthcare by OHCA survivors two years before and one year after cardiac arrest. Methods Adult patients with OHCA of medical cause, who survived >30 days, were identified in the Norwegian Cardiac Arrest Registry. The Norwegian Patient Registry, The Cause of Death Registry, and The Norwegian Registry for Primary Healthcare provided data on survival and the use of healthcare services. We investigated the use of primary, specialist and mental healthcare, as well as rehabilitation services. Results In 2015–2018, 13,112 OHCA cases were identified; 1435 (14%) patients survived >30 days (6.8/100,000 patients/year). The proportion of patients in the cohort that used primary healthcare each month increased form 43% before to 69% after OHCA to (p 0.001). The observed increases in primary, specialist and mental healthcare use started two weeks, six months, and eight months before OHCA, respectively. Half of the patients had contact with primary healthcare services on the same day as the cardiac arrest. Two out of five patients were registered for rehabilitation after OHCA. Conclusion The use of primary, specialist and mental healthcare services increased before OHCA and remained significantly higher the year after OHCA. Less than half of the patients surviving cardiac arrest were registered for rehabilitation.

• Petrovich, Polina; Berve, Per-Olav Stefferud; Roald, Borghild; Kongsgård, Håvard Wahl; Stray-Pedersen, Arne & Kramer-Johansen, Jo [Show all 7 contributors for this article] (2023). Injuries associated with mechanical chest compressions and active decompressions after out-of-hospital cardiac arrest: A subgroup analysis of non-survivors from a randomized study. Resuscitation Plus. 13:100362, p. 1–7. doi: 10.1016/j.resplu.2023.100362. Full text in Research Archive Show summary

  Background Both skeletal and visceral injuries are reported after cardiopulmonary resuscitation (CPR). This subgroup analysis of a randomized clinical study describes/compares autopsy documented injury patterns caused by two mechanical, piston-based chest compression devices: standard LUCAS® 2 (control) and LUCAS® 2 with active decompression (AD, intervention) in non-survivors with out-of-hospital cardiac arrest (CA). Method We compared injuries documented by autopsies (medical/forensic) after control and intervention CPR based on written relatives consent to use patients’ data. The pathologists were blinded for the device used. The cause of CA and injuries reported were based on a prespecified study autopsy template. We used Pearson's chi-squared test and logistic regression analysis with an alpha level of 0.05. Results 221 patients were included in the main study (April 2015–April 2017) and 207 did not survive. Of these, 114 (55%, 64 control and 50 intervention) underwent medical (N = 73) or forensic (N = 41) autopsy. The cause of CA was cardiac 53%, respiratory 17%, overdose/intoxication 14%, ruptured aorta 10%, neurological 1%, and other 5%. There were no differences between control and intervention in the incidence of rib fractures (67% vs 72%; p-value = 0.58), or sternal fractures (44% vs 48%; p-value = 0.65), respectively. The most frequent non-skeletal complication was bleeding (26% of all patients) and intrathoracic was the most common location. Ten of the 114 patients had internal organ injuries, where lungs were most affected. Conclusion In non-survivors of OHCA patients, the most frequent cause of cardiac arrest was cardiogenic. Skeletal and non-skeletal fractures/injuries were found in both control and intervention groups. Bleeding was the most common non-skeletal complication. Internal organ injuries were rare.

• Olasveengen, Theresa M.; Skaare, Christiane; Skjerven-Martinsen, Marianne; Hoff-Olsen, Per; Kramer-Johansen, Jo & Nordum, Fredrik Hoff [Show all 9 contributors for this article] (2023). Lung tissue injury and hemodynamic effects of ventilations synchronized or unsynchronized to continuous chest compressions in a porcine cardiac arrest model. Resuscitation Plus. 17. doi: 10.1016/j.resplu.2023.100530. Full text in Research Archive Show summary

  Aim Compare lung injury and hemodynamic effects in synchronized ventilations (between two chest compressions) vs. unsynchronized ventilations during cardiopulmonary resuscitation (CPR) in a porcine model of cardiac arrest. Methods Twenty pigs were randomized to either synchronized or unsynchronized group. Ventricular fibrillation was induced electrically and left for 1.5 minutes. Four minutes of basic chest compression:ventilation (30:2) CPR was followed by eight minutes of either synchronized or unsynchronized ventilations (10/min) during continuous compressions before defibrillation was attempted. Aortic, right atrial and intracerebral pressures, carotid and cerebral blood flow and cardiac output were measured. Airway monitoring included capnography and respiratory function monitor. Macro- and microscopic lung injuries were assessed post-mortem. Results There were no significant differences between groups in any of the measured hemodynamic variables or inspiration time (0.4 vs. 1.0 s, p = 0.05). The synchronized ventilation group had lower median peak inspiratory airway pressure (57 vs. 94 cm H2O, p < 0.001), lower minute ventilation (3.7 vs. 9.4 l min−1, p < 0.001), lower pH (7.31 vs. 7.53, p < 0.001), higher pCO2 (5.2 vs. 2.5 kPa, p < 0.001) and lower pO2 (31.6 vs. 54.7 kPa, p < 0.001) compared to the unsynchronized group after 12 minutes of CPR. There was significant lung injury after CPR in both synchronized and unsynchronized groups. Conclusion Synchronized and unsynchronized ventilations resulted in similar hemodynamics and lung injury during continuous mechanical compressions of pigs in cardiac arrest. Animals that received unsynchronized ventilations with one second inspiration time at a rate of ten ventilations per minute were hyperventilated and hyperoxygenated.

• Katzenschlager, Stephan; Kelpanides, Inga Katherina; Ristau, Patrick; Huck, Matthias; Seewald, Stephan & Brenner, Sebastian [Show all 13 contributors for this article] (2023). Out-of-hospital cardiac arrest in children: an epidemiological study based on the German Resuscitation Registry identifying modifiable factors for return of spontaneous circulation. Critical Care. ISSN 1364-8535. 27(1). doi: 10.1186/s13054-023-04630-3. Full text in Research Archive Show summary

  Aim This work provides an epidemiological overview of out-of-hospital cardiac arrest (OHCA) in children in Germany between 2007 and 2021. We wanted to identify modifiable factors associated with survival. Methods Data from the German Resuscitation Registry (GRR) were used, and we included patients registered between 1st January 2007 and 31st December 2021. We included children aged between > 7 days and 17 years, where cardiopulmonary resuscitation (CPR) was started, and treatment was continued by emergency medical services (EMS). Incidences and descriptive analyses are presented for the overall cohort and each age group. Multivariate binary logistic regression was performed on the whole cohort to determine the influence of (1) CPR with/without ventilation started by bystander, (2) OHCA witnessed status and (3) night-time on the outcome hospital admission with return of spontaneous circulation (ROSC). Results OHCA in children aged < 1 year had the highest incidence of the same age group, with 23.42 per 100 000. Overall, hypoxia was the leading presumed cause of OHCA, whereas trauma and drowning accounted for a high proportion in children aged > 1 year. Bystander-witnessed OHCA and bystander CPR rate were highest in children aged 1–4 years, with 43.9% and 62.3%, respectively. In reference to EMS-started CPR, bystander CPR with ventilation were associated with an increased odds ratio for ROSC at hospital admission after adjusting for age, sex, year of OHCA and location of OHCA. Conclusion This study provides an epidemiological overview of OHCA in children in Germany and identifies bystander CPR with ventilation as one primary factor for survival. Trial registrations German Clinical Trial Register: DRKS00030989, December 28th 2022. Graphical Abstract

• Guterud, Mona; Bugge, Helge Fagerheim; Røislien, Jo; Kramer-Johansen, Jo; Toft, Mathias & Ihle-Hansen, Hege Beathe [Show all 11 contributors for this article] (2023). Prehospital screening of acute stroke with the National Institutes of Health Stroke Scale (ParaNASPP): a stepped-wedge, cluster-randomised controlled trial. Lancet Neurology. ISSN 1474-4422. 22(9), p. 800–811. doi: 10.1016/S1474-4422(23)00237-5. Full text in Research Archive Show summary

  Background Timely treatment of acute stroke depends on early identification and triage. Improved methods for recognition of stroke in the prehospital setting are needed. We aimed to assess whether use of the National Institutes of Health Stroke Scale (NIHSS) by paramedics in the ambulance could improve communication with the hospital, augment triage, and enhance diagnostic accuracy of acute stroke. Methods The Paramedic Norwegian Acute Stroke Prehospital Project (ParaNASPP) was a stepped-wedge, single-blind, cluster-randomised controlled trial. Patients with suspected acute stroke, who were evaluated by paramedics from five ambulance stations in Oslo, Norway, were eligible for inclusion. The five ambulance stations (defined as clusters) all initially managed patients according to a standard stroke protocol (control group), with randomised sequential crossover of each station to the intervention group. The intervention consisted of supervised training on NIHSS scoring, a mobile application to aid scoring, and standardised communication with stroke physicians. Random allocation was done via a simple lottery draw by administrators at Oslo University Hospital, who were independent of the research team. Allocation concealment was not possible due to the nature of the intervention. The primary outcome was the positive predictive value (PPV) for prehospital identification of patients with a final discharge diagnosis of acute stroke, analysed by intention to treat. Prespecified secondary safety outcomes were median prehospital on-scene time and median door-to-needle time. This trial is registered with ClinicalTrials.gov, NCT04137874, and is completed. Findings Between June 3, 2019, and July 1, 2021, 935 patients were evaluated by paramedics for suspected acute stroke. 134 patients met exclusion criteria or did not consent to participate. The primary analysis included 447 patients in the intervention group and 354 in the control group. There was no difference in PPV for prehospital identification of patients with a final discharge diagnosis of acute stroke between the intervention group (48·1%, 95% CI 43·4–52·8) and control group (45·8%, 40·5–51·1), with an estimated percentage points difference between groups of 2·3 (95% CI –4·6 to 9·3; p=0·51). Median prehospital on-scene time increased by 5 min in the intervention group (29 min [IQR 23–36] vs 24 min [19–31]; p<0·0001), whereas median door-to-needle time was similar between groups (26 min [21–36] vs 27 min [20–36]; p=0·90). No prehospital deaths were reported in either group. Interpretation The intervention did not improve diagnostic accuracy in patients with suspected stroke. A general increase in prehospital time during the pandemic and the identification of smaller strokes that require more deliberation are possible explanations for the increased on-scene time. The ParaNASPP model is to be implemented in Norway from 2023, and will provide real-life data for further research.

• Isern, Cecilie Benedicte; Kramer-Johansen, Jo; Tjelmeland, Ingvild Beathe Myrhaugen; Bahr, Roald & Berge, Hilde Moseby (2023). A 3-year population-based study of exercise-related sudden cardiac arrest among 12- to 50-year-old Norwegians. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 33(8). doi: 10.1111/sms.14400. Full text in Research Archive Show summary

  Introduction: Regular exercise is associated with reduced risk of cardiovascular disease. Paradoxically, an increased risk of sudden cardiac arrest (SCA) is documented during or immediately after exercise and in athletes compared to the nonathletic population. Our objective was to identify, through multiple sources, the total number of exercise-related versus non-exercise-related SCA in the young population in Norway. Methods: We collected primary data from the prospective Norwegian Cardiac Arrest Registry (NorCAR) for all patients aged 12–50 suffering SCA of presumed cardiac cause from 2015 to 2017. We collected secondary data about prior physical activity and the SCA, through questionnaires. We searched media reports for SCA incidents in sports. Exercise-related SCA is defined as SCA during or <1 h after exercise. Results: Overall, 624 patients, median age 43 years, were included from NorCAR. Two thirds (393) replied to the study invitation, of whom 236 answered the questionnaires: 95 survivors and 141 next of kin. The media search resulted in 18 relevant hits. With a multiple source approach, we identified 63 cases of exercise-related SCA, equivalent to an incidence of 0.8/100 000 person-years, versus 7.8/100 000 person-years of non-exercise-related SCA. Among those who answered (n = 236), almost two thirds (59%) exercised regularly, most commonly (45%) 1–4 h/week. Endurance exercise (38%) was the most prevalent type of regular exercise and the most common activity during exercise-related SCA (53%). Conclusion: The burden of exercise-related SCA was low (0.8 per 100 000 person-years) and ten times lower than non-exercise-related SCA in the young population in Norway.

• Isern, Cecilie Benedicte; Nilsson, Birgitta Blakstad; Garratt, Andrew; Kramer-Johansen, Jo; Tjelmeland, Ingvild Beathe Myrhaugen & Berge, Hilde Moseby (2023). Health-related quality of life in young Norwegian survivors of out-of-hospital cardiac arrest related to pre-arrest exercise habits. Resuscitation Plus. 16. doi: 10.1016/j.resplu.2023.100478. Full text in Research Archive Show summary

  Aim: To compare health-related quality of life (HRQoL) in young survivors of out-of-hospital cardiac arrest (OHCA) in Norway with an age and sex- matched reference population and to assess the associations between exercise volume prior to OHCA and HRQoL after. Methods: We present data from survivors aged 18–50 years registered with OHCA in the Norwegian Cardiac Arrest Registry between January 1st 2015 and December 31st 2017. Survivors were invited to answer two questionnaires; (1) the Short Form 36 (SF-36) Health Survey Version 1, and (2) about exercise habits prior to OHCA. Respondents were randomly matched 1:1 for age and sex with a reference population (data were available from the Norwegian Centre for Research Data). Results: Of the 175 survivors invited, 95 (54%) responded, median age was 44 (range 35–48) years, 26 (27%) females. Valid results for SF-36 were available for 91 survivors, of whom 87 reported pre-OHCA exercise-volume. Prior to OHCA, 21 did no regular exercise, 44 exercised 1–4 hours/week and 22 exercised 5 hours/week. Compared to the reference population survivors had significantly (p < 0.01) poorer SF-36 scores for scales relating to physical- and mental health. SF-36 scale scores were similar in survivors who did and did not exercise regularly. Within the regular exercisers, survivors reporting 5 hours of exercise/week had better SF-36 scores than those exercising less. Conclusion: Poorer HRQoL in survivors compared to the reference population should prompt us to explore how treatment and rehabilitation could be improved and adapted. More exercise before OHCA favoured better HRQoL after, which aligns well with the recognised positive association between HRQoL and physical activity in general.

• Fremstad, Kjell Otto; Lindenskov, Paal Helge H.; Ihle-Hansen, Hege; Jamtli, Bjørn; Kramer-Johansen, Jo & Hardeland, Camilla [Show all 8 contributors for this article] (2022). Veien inn til sykehus for pasienter innlagt ved mistanke om akutt hjerneslag. Sykepleien Forskning. ISSN 1890-2936. 17(17). doi: 10.4220/Sykepleienf.2022.89354. Full text in Research Archive Show summary

  Bakgrunn: Hjerneslag er en tidskritisk tilstand, men fremdeles ankommer under halvparten av pasientene sykehus innen fire timer fra symptomdebut. En mulig forklaring på forsinkelsen kan være at første kontakt med helsevesenet er hos legevakten eller fastlegen. Hensikt: Hensikten med denne studien var å kartlegge innleggende instans for pasienter ved mistanke om akutt hjerneslag før de kom til akuttmottaket ved Oslo universitetssykehus (OUS) på Ullevål. Vi ville også kartlegge hvorvidt innleggelsesinstans kunne korreleres til slagdiagnose ved utskrivelse. Metode: En retrospektiv observasjonsstudie identifiserte alle pasienter der mistanke om hjerneslag var innleggelsesårsaken på akuttmottaket ved Ullevål i 2018. Vi grupperte pasientene etter innleggende instans: ambulanse, legevakt, fastlege eller direkte kontakt. Vi sammenliknet utskrivelsesdiagnoser «hjerneslag» eller «ikke hjerneslag» etter innleggende instans og fordelte på alder ved å bruke kjikvadrattest. Resultat: Totalt 1399 pasienter med mistanke om hjerneslag ble innlagt, hvorav 594 (42 prosent) fikk en hjerneslagdiagnose. Medianalderen var 72 år, og 52 prosent var kvinner. Halvparten ble innlagt direkte med ambulanse, en tredel via legevakten og 12 prosent fra fastlegen. Signifikant flere pasienter av de som ble innlagt med ambulanse (51 prosent), fikk hjerneslag som utskrivelsesdiagnose sammenliknet med pasienter som kom via henholdsvis legevakt (29 prosent) eller fastlege (40 prosent) (kjikvadrat p < 0,001). Pasientene som ble innlagt med ambulanse, var signifikant eldre enn pasientene som kom via legevakten (72 år versus 65 år, p < 0,001). Konklusjon: Kun halvparten av pasientene med symptomer på mistenkt hjerneslag ble innlagt med ambulanse. Pasientene som ble innlagt direkte med ambulanse, ble oftere utskrevet med en hjerneslagdiagnose. Vi trenger mer kunnskap om årsakene til at de resterende pasientene kom via fastlegen eller legevakten.

• Tjelmeland, Ingvild Beathe Myrhaugen; Alm-Kruse, Kristin; Gräsner, Jan-Thorsten; Isern, Cecilie Benedicte; Jakisch, Barbara & Kramer-Johansen, Jo [Show all 9 contributors for this article] (2022). Importance of reporting survival as incidence: a cross-sectional comparative study on out-of-hospital cardiac arrest registry data from Germany and Norway. BMJ Open. 12(2). doi: 10.1136/bmjopen-2021-058381. Full text in Research Archive Show summary

  Objectives Health registries are a unique source of information about current practice and can describe disease burden in a population. We aimed to understand similarities and differences in the German Resuscitation Registry (GRR) and the Norwegian Cardiac Arrest Registry (NorCAR) and compare incidence and survival for patients resuscitated after out-of-hospital cardiac arrest. Design A cross-sectional comparative analysis reporting incidence and outcome on a population level. Setting We included data from the cardiac arrest registries in Germany and Norway. Participants Patients resuscitated between 1 January 2015 and 31 December 2019 were included, resulting in 29 222 cases from GRR and 16 406 cases from NorCAR. From GRR, only emergency medical services (EMS) reporting survival information for patients admitted to the hospital were included. Primary and secondary outcome measures This study focused on the EMS systems, the registries and the patients included in both registries. The results compare the total incidence, incidence of patients resuscitated by EMS, and the incidence of survival. Results We found an incidence of 68 per 100 000 inhabitants in GRR and 63 in NorCAR. The incidence of patients treated by EMS was 67 in GRR and 53 in NorCAR. The incidence of patients arriving at a hospital was higher in GRR (24.3) than in NorCAR (15.1), but survival was similar (8 in GRR and 7.8 in NorCAR). Conclusion GRR is a voluntary registry, and in-hospital information is not reported for all cases. NorCAR has mandatory reporting from all EMS and hospitals. EMS in Germany starts treatment on more patients and bring a higher number to hospital, but we found no difference in the incidence of survival. This study has improved our knowledge of both registries and highlighted the importance of reporting survival as incidence when comparing registries.

• Guterud, Mona Marie; Bugge, Helge Fagerheim; Røislien, Jo; Larsen, Karianne; Eriksen, Erik & Mikkelsen, Martin Lerstang [Show all 10 contributors for this article] (2022). Interrater Agreement on National Institutes of Health Stroke Scale Between Paramedics and Stroke Physicians: Validation Study for the Digital Training Model in the Paramedic Norwegian Acute Stroke Prehospital Project. JMIR Neurotechnology. 1(1). doi: 10.2196/39444. Full text in Research Archive
• Andresen, Åke Erling Lappen; Kramer-Johansen, Jo & Kristiansen, Thomas (2022). Emergency cricothyroidotomy in difficult airway simulation – a national observational study of Air Ambulance crew performance. BMC Emergency Medicine. 22(1), p. 1–8. doi: 10.1186/s12873-022-00624-6. Full text in Research Archive Show summary

  Background: Advanced prehospital airway management includes complex procedures carried out in challeng‑ ing environments, necessitating a high level of technical and non-technical skills. We aimed to describe Norwegian Air Ambulance-crews’ performance in a difcult airway scenario simulation, ending with a “cannot intubate, cannot oxygenate”-situation. Methods: The study describes Air Ambulance crews’ management of a simulated difcult airway scenario. We used video-observation to assess time expenditure according to pre-defned time intervals and technical and non-techni‑ cal performance was evaluated according to a structured evaluation-form. Results: Thirty-six crews successfully completed the emergency cricothyroidotomy with mean procedural time 118 (SD: ±70) seconds. There was variation among the crews in terms of completed procedural steps, including prepara‑ tion of equipment, patient- monitoring and management. The participants demonstrated uniform and appropriate situational awareness, and efective communication and resource utilization within the crews was evident. Conclusions: We found that Norwegian Air Ambulance crews managed a prehospital “cannot intubate, cannot oxygenate”-situation with an emergency cricothyroidotomy under stressful conditions with efective communica‑ tion and resource utilization, and within a reasonable timeframe. Some discrepancies between standard operating procedures and performance are observed. Further studies to assess the impact of check lists on procedural aspects of airway management in the prehospital environment are warranted.

• Harring, Astrid Karina; Tjelmeland, Ingvild Beathe Myrhaugen; Andenæs, Randi & Kramer-Johansen, Jo (2022). Blir beslutninger om behandlingsbegrensninger respektert utenfor sykehus når man har ringt 113? Tidsskrift for omsorgsforskning. ISSN 2387-5976. 8, p. 1–13. doi: 10.18261/tfo.8.3.1. Full text in Research Archive Show summary

  Bakgrunn: Til tross for at det foreligger dokumentert beslutning om at pasienter ikke skal gjenopplives ved hjertestans, mottok likevel noen hjerte- og lungeredning (HLR). Vi ønsket å undersøke hvor ofte dette forekommer utenfor sykehus i Norge. Metode: Vi hentet data fra Norsk hjertestansregister fra perioden 2015–2019. Vi inkluderte alle pasienter over 60 år som fikk hjertestans, enten hjemme eller på helse- og omsorgsinstitusjon. Vi undersøkte om forhåndsbeslutning av behandlingsbegrensning (HLR minus) var årsaken til at ambulansen ikke startet gjenopplivning, eller at gjenopplivning ble avsluttet. Resultat: Av 8407 hjertestans fikk 198 (2,3 %) pasienter som viste seg å ha HLR minus, likevel HLR av tilstedeværende personer eller ambulansepersonell. To tredjedeler av disse hendelsene skjedde på helse- og omsorgsinstitusjoner. Konklusjon: For å forhindre at pasienter hvor det er gjort en beslutning om HLR minus, får slik behandling, er det viktig at det foreligger dokumentasjon som er tydelig og lett tilgjengelig for alt helsepersonell, inkludert medisinsk nødmeldetjeneste, ambulanse og legevakt. Kritisk informasjon i pasientens kjernejournal fremstår som et godt egnet sted for å sikre enhetlig dokumentasjon og tilgang.

• Idland, Siri; Iversen, Emil; Brattebø, Guttorm; Kramer-Johansen, Jo & Hjortdahl, Magnus (2022). From hearing to seeing: medical dispatchers' experience with use of video streaming in medical emergency calls - a qualitative study. BMJ Open. 12(12), p. 1–7. doi: 10.1136/bmjopen-2022-063395. Full text in Research Archive Show summary

  Objectives: Video streaming has recently been introduced as an additional tool for communication between medical dispatchers and caller. Research implies that video streaming may be a useful tool for the dispatchers, but more knowledge is needed. With this study, we wanted to explore how the dispatchers experience using video streaming as an additional tool in medical emergency calls. Design: An explorative, qualitative study using semi-structured focus group interviews. Setting: Two emergency medical communications centres in Norway where video streaming recently had been introduced. Interviews were conducted during 24 June 2020 and 26 June 2020. Participants: We recruited 25 medical dispatchers, either nurses or emergency medical technicians who worked at the two centres. Results: The results are categorised into three themes: (1) change in dispatcher’s perception of the patient and the situation, (2) reassurance for the dispatcher and (3) worries about increased time consumption and the possibility of unpleasant images. Conclusion: The dispatchers experienced that the use of video streaming in medical emergency calls might contribute to a better comprehension of the situation and following more precise resource allocation, as well as greater reassurance for the dispatcher and improved relationship between the dispatcher and the caller. Further research with an aim to measure effects and safety of video streaming during medical emergency calls is needed.

• Alm-Kruse, Kristin; Sørensen, Gro; Osbakk, Svein Are; Sunde, Kjetil; Bendz, Bjørn & Andersen, Geir Øystein [Show all 9 contributors for this article] (2021). Outcome in refractory out-of-hospital cardiac arrest before and after implementation of an ECPR protocol. Resuscitation. ISSN 0300-9572. doi: 10.1016/j.resuscitation.2021.01.038. Full text in Research Archive Show summary

  Aim To compare the outcomes in patients with refractory out-of-hospital cardiac arrest (OHCA) fulfilling the criteria for extracorporeal cardiopulmonary resuscitation (ECPR) before and after implementation of an ECPR protocol, whether the patient received ECPR or not. Methods We compared cardiac arrest registry data before (2014–2015) and after (2016–2019) implementation of the ECPR protocol. The ECPR criteria were presumed cardiac origin, witnessed arrest with ventricular fibrillation, bystander CPR, age 18–65, advanced life support (ALS) within 15 min and ALS > 10 min without return of spontaneous circulation (ROSC). The primary outcome was 30-day survival; the secondary outcomes were sustained ROSC, neurological outcome and the proportion of patients transported with ongoing ALS. Results There were 1086 and 3135 patients in the pre- and post-implementation sample; 48 (4%) and 100 (3%) met the ECPR criteria, respectively. Of these, 21 (44%) vs. 37 (37%) were alive after 30 days, p = 0.4, and 30 (63%) vs. 50 (50%) achieved sustained ROSC, p = 0.2. All survivors in the pre-implementation sample had cerebral performance category 1–2 vs. 30 (81%) in the post-implementation sample, p = 0.03. Of the patients fulfilling the ECPR criteria, 7 (15%) and 26 (26%), p = 0.1, were transported with ongoing ALS in the pre- and post-implementation sample, respectively. Conclusions There were no differences in 30-day survival or prehospital ROSC in patients with refractory OHCA before and after initiation of an ECPR protocol.

• Alm-Kruse, Kristin; Tjelmeland, Ingvild Beathe Myrhaugen; Kongsgård, Håvard Wahl; Kvåle, Rune & Kramer-Johansen, Jo (2021). Case completeness in the Norwegian Cardiac Arrest Registry. Resuscitation Plus. 8, p. 1–7. doi: 10.1016/j.resplu.2021.100182. Full text in Research Archive Show summary

  Introduction This study aimed to assess the case completeness of out-of-hospital cardiac arrests (OHCA) in the Norwegian Cardiac Arrest Registry (NorCAR) and describe the differences between the registered and missing patients identified from the case-control assessment. Methods We identified the relevant patients in the Norwegian Patient Registry and the Norwegian Cause of Death Registry and compared them with the patients in NorCAR. Data processors used patient records to confirm if the potential cardiac arrest cases met the inclusion criteria in NorCAR. Results Between 2015 and 2017, 8612 OHCA patients were registered in NorCAR. Through the Patient Registry and the Cause of Death Registry we identified 11,114 potential OHCA patients, 3469 of these were already registered in NorCAR. After evaluating the patient records for the remaining 7645 patients, we found 344 patients (4%), were eligible for inclusion in NorCAR, giving a case completeness of 96%. The registered and missing patients were similar in age and gender distribution. Initial shockable rhythm and presumed cause were also comparable. However, the missing patients more frequently achieved return of spontaneous circulation, were more often transported to hospital, and had higher survival rates. The already registered patients had more key variables registered than the missing patients. Conclusion Our results indicate high case completeness in NorCAR. The missing patients were too few to introduce significant changes in the distribution of patient characteristics, indicating that NorCAR is representative of the Norwegian OHCA population.

• Berve, Per-Olav Stefferud; Irusta, Unai; Kramer-Johansen, Jo; Skålhegg, Tore; Aramendi, Elisabete & Wik, Lars (2021). Tidal volume measurements via transthoracic impedance waveform characteristics: The effect of age, body mass index and gender. A single centre interventional study. Resuscitation. ISSN 0300-9572. 167, p. 218–224. doi: 10.1016/j.resuscitation.2021.08.041. Full text in Research Archive
• Tjelmeland, Ingvild B M; Wnent, Jan; Masterson, Siobhan; Kramer-Johansen, Jo & Gräsner, Jan-Thorsten (2021). Protocol for a cohort study of the impact of the COVID-19 pandemic on the rate and incidence of bystander cardiopulmonary resuscitation (CPR) after out-of-hospital cardiac arrest. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. 29(1), p. 1–5. doi: 10.1186/s13049-021-00890-6. Full text in Research Archive Show summary

  Background Survival after out-of-hospital cardiac arrest (OHCA) is dependent on early recognition, early cardiopulmonary resuscitation (CPR) and early defibrillation. The purpose of CPR is to maintain some blood flow until the arrival of the emergency medical services (EMS). Our concern is that the COVID-19 pandemic has had a negative effect on the number of patients who get CPR before EMS arrival. The aim of this study is to compare the incidence of bystander CPR during the pandemic with data from before the pandemic. Methods The protocol is for a retrospective cohort study where data from existing registries will be used. All participating registries will share aggregated data from 2017 to 2020, and the study team will compare the results from 2020 to results from 2017 to 2019. Due to the General Data Protection Regulation, each participating registry will check for completeness and plausibility, and perform all aggregation of data locally. In the following analysis different registries will be considered as random samples and analysed by means of a generalized linear mixed effects model with Poisson distribution for the outcome, the population covered as offsets, and different registries as random factors. Discussion This study does not present the prospect of direct benefit to the patient, but does provide an opportunity to gain a better understanding of the epidemiology of bystander CPR for OHCA patients during a pandemic. By comparing data during the pandemic with already collected information in established registries we believe we can gain valuable information about changes in public response to out-of-hospital cardiac arrest.

• Berve, Per-Olav Stefferud; Hardig, Bjarne Madsen; Skålhegg, Tore; Kongsgård, Håvard Wahl; Kramer-Johansen, Jo & Wik, Lars (2021). Mechanical active compression-decompression versus standard mechanical cardiopulmonary resuscitation: A randomised haemodynamic out-of-hospital cardiac arrest study. Resuscitation. ISSN 0300-9572. 170. doi: 10.1016/j.resuscitation.2021.10.026. Full text in Research Archive
• Niles, Dana N; Skaare, Christiane; Foglia, Elizabeth E; Insley, Elena; Cines, Courtney & Olasveengen, Theresa M. [Show all 11 contributors for this article] (2021). Effect of a positive pressure ventilation-refresher program on ventilation skill performance during simulated newborn resuscitation. Resuscitation Plus. 5. doi: 10.1016/j.resplu.2021.100091. Full text in Research Archive Show summary

  Aim Clinical staff highly proficient in neonatal resuscitation are essential to ensure prompt, effective positive pressure ventilation (PPV) for infants that do not breathe spontaneously after birth. However, it is well-documented that resuscitation competency is transient after standard training. We hypothesized that brief, repeated PPV psychomotor skill refresher training would improve PPV performance for newborn care nurses. Methods Subjects completed a blinded baseline and post PPV-skills assessment. Data on volume and rate for each ventilation was recorded. After baseline assessment, subjects completed PPV-Refreshers over 3 months consisting of psychomotor skill training using a newborn manikin with visual feedback. Subjects provided PPV until they could deliver ≥30 s of PPV meeting targets for volume (10−21 mL) and rate (40–60 ventilations per minute [vpm]). Baseline and post assessments were compared for total number PPV delivered, number target PPV delivered (volume 10−21 mL), mean volume and mean rate (Wilcoxon signed-rank test, median[IQR]). Results Twenty-six subjects were enrolled and completed a baseline assessment; 24 (92%) completed a post-assessment; 2 (8%) were lost to follow-up. Over 3 months, a mean 3.2 (range 1–6) PPV-Refreshers/subject were completed. Compared to baseline, subjects demonstrated significant improvement for total (57 [36–74] vs. 33 [26–46]; p = 0.0007) and target PPV (23 [13–23] vs. 11 [5–21]; p = 0.024), and a significant change in mean volume (mL) (11.5 [10.2–13] vs. 13.4 [11–16]; p = 0.02) and mean rate (vpm) (54 [45–61] vs. 40 [28–49]; p = 0.019). Conclusions A PPV-Refresher program with brief, repeated psychomotor skill practice significantly improved PPV performance with the greatest improvement in total PPV and target PPV. Additional investigation is warranted to determine optimal PPV-Refresher frequency. Registered at ClinicalTrials.gov #NCT02347241

• Isasi, Iraia; Alonso, Erik; Irusta, Unai; Aramendi, Elisabete; Zabihi, Morteza & Rad, Ali Bahrami [Show all 9 contributors for this article] (2021). A Machine Learning-Based Pulse Detection Algorithm for Use During Cardiopulmonary Resuscitation. Computing in cardiology. ISSN 2325-8861. 48. doi: 10.23919/CinC53138.2021.9662778. Full text in Research Archive
• Hardeland, Camilla; Claesson, Andreas; Blom, Marieke T; Blomberg, Stig Nikolaj Fasmer; Folke, Fredrik & Hollenberg, Jacob [Show all 14 contributors for this article] (2021). Description of call handling in emergency medical dispatch centres in Scandinavia: recognition of out-of-hospital cardiac arrests and dispatcher-assisted CPR. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. doi: 10.1186/s13049-021-00903-4. Full text in Research Archive Show summary

  Background The European resuscitation council have highlighted emergency medical dispatch centres as an important key player for early recognition of Out-of-Hospital Cardiac Arrest (OHCA) and in providing dispatcher assisted cardiopulmonary resuscitation (CPR) before arrival of emergency medical services. Early recognition is associated with increased bystander CPR and improved survival rates. The aim of this study is to describe OHCA call handling in emergency medical dispatch centres in Copenhagen (Denmark), Stockholm (Sweden) and Oslo (Norway) with focus on sensitivity of recognition of OHCA, provision of dispatcher-assisted CPR and time intervals when CPR is initiated during the emergency call (NO-CPRprior), and to describe OHCA call handling when CPR is initiated prior to the emergency call (CPRprior). Methods Baseline data of consecutive OHCA eligible for inclusion starting January 1st 2016 were collected from respective cardiac arrest registries. A template based on the Cardiac Arrest Registry to Enhance Survival definition catalogue was used to extract data from respective cardiac arrest registries and from corresponding audio files from emergency medical dispatch centres. Cases were divided in two groups: NO-CPRprior and CPRprior and data collection continued until 200 cases were collected in the NO-CPRprior-group. Results NO-CPRprior OHCA was recognised in 71% of the calls in Copenhagen, 83% in Stockholm, and 96% in Oslo. Abnormal breathing was addressed in 34, 7 and 98% of cases and CPR instructions were started in 50, 60, and 80%, respectively. Median time (mm:ss) to first chest compression was 02:35 (Copenhagen), 03:50 (Stockholm) and 02:58 (Oslo). Assessment of CPR quality was performed in 80, 74, and 74% of the cases. CPRprior comprised 71 cases in Copenhagen, 9 in Stockholm, and 38 in Oslo. Dispatchers still started CPR instructions in 41, 22, and 40% of the calls, respectively and provided quality assessment in 71, 100, and 80% in these respective instances. Conclusions We observed variations in OHCA recognition in 71–96% and dispatcher assisted-CPR were provided in 50–80% in NO-CPRprior calls. In cases where CPR was initiated prior to emergency calls, dispatchers were less likely to start CPR instructions but provided quality assessments during instructions.

• Eftestøl, Trygve Christian; Stokka, Svein Erik; Kvaløy, Jan Terje; Rad, Ali Bahrami; Irusta, Unai & Aramendi, Elisabete [Show all 11 contributors for this article] (2020). A probabilistic function to model the relationship between quality of chest compressions and the physiological response for patients in cardiac arrest. Computing in cardiology. ISSN 2325-8861. 47. doi: 10.22489/CinC.2020.073. Full text in Research Archive Show summary

  Cardiopulmonary resuscitation quality (CPRQ) parameters can be derived from electric signals obtained during resuscitation. We propose to model a probabilistic relationship between CPRQ parameters and the physiological response as judged by ECG-features, to guide therapy in a clinical context. A total of 821 compression sequences were extracted from 394 out-of-hospital resuscitation episodes. Sequences were categorized as effective if the post sequence cardiac rhythm had better prognosis than the pre-sequence rhythm by a positive difference, otherwise as non effective if the difference was negative. CPRQ parameters related to depth and rate were calculated. Three alternative approaches were designed for the binary classifier based on the CPRQ parameters: quadratic discriminant analysis (QDA), logistic regression (LR) and artificial neural networks (ANN). The positive class discriminant function defined the probability of effective compressions (Pec). The classification accuracies were around 0.6 for all three models. The highest probability estimates of effective chest compressions corresponded to the depth (5-6 cm) and rate (100-120 min-1 ) currently recommended in the CPR guidelines. We have proposed a novel method to relate the quality of chest compressions to the physiologic response to CPR.

• Isasi, Iraia; Irusta, Unai; Aramendi, Elisabete; Eftestøl, Trygve Christian; Kramer-Johansen, Jo & Wik, Lars (2020). Rhythm Analysis during Cardiopulmonary Resuscitation Using Convolutional Neural Networks. Entropy. 22(6). doi: 10.3390/e22060595. Full text in Research Archive Show summary

  Chest compressions during cardiopulmonary resuscitation (CPR) induce artifacts in the ECG that may provoque inaccurate rhythm classification by the algorithm of the defibrillator. The objective of this study was to design an algorithm to produce reliable shock/no-shock decisions during CPR using convolutional neural networks (CNN). A total of 3319 ECG segments of 9 s extracted during chest compressions were used, whereof 586 were shockable and 2733 nonshockable. Chest compression artifacts were removed using a Recursive Least Squares (RLS) filter, and the filtered ECG was fed to a CNN classifier with three convolutional blocks and two fully connected layers for the shock/no-shock classification. A 5-fold cross validation architecture was adopted to train/test the algorithm, and the proccess was repeated 100 times to statistically characterize the performance. The proposed architecture was compared to the most accurate algorithms that include handcrafted ECG features and a random forest classifier (baseline model). The median (90% confidence interval) sensitivity, specificity, accuracy and balanced accuracy of the method were 95.8% (94.6–96.8), 96.1% (95.8–96.5), 96.1% (95.7–96.4) and 96.0% (95.5–96.5), respectively. The proposed algorithm outperformed the baseline model by 0.6-points in accuracy. This new approach shows the potential of deep learning methods to provide reliable diagnosis of the cardiac rhythm without interrupting chest compression therapy.

• Lasa, Haizea; Irusta, Unai; Eftestøl, Trygve Christian; Aramendi, Elisabete; Rad, Ali Bahrami & Kramer-Johansen, Jo [Show all 7 contributors for this article] (2020). Multimodal biosignal analysis algorithm for the classification of cardiac rhythms during resuscitation. Computing in cardiology. ISSN 2325-8861. 47. doi: 10.22489/CinC.2020.347. Full text in Research Archive Show summary

  Session S52, ID 347 - Multimodal Biosignal Analysis Algorithm for the Classification of Cardiac Rhythms During Resuscitation Haizea Lasa1, Unai Irusta2, Trygve Eftestøl3, Elisabete Aramendi2, Ali Bahrami Rad4, Jo Kramer-Johansen5, Lars Wik5 1University of the Basque Country (UPV/EHU), 2UPV/EHU, 3University of Stavanger, 4Emory University, 5Oslo University Hospital

• Oving, Iris; Graaf, Corina de; Karlsson, Lena; Jonsson, Martin; Kramer-Johansen, Jo & Berglund, Ellinor [Show all 17 contributors for this article] (2020). Occurrence of shockable rhythm in out-of-hospital cardiac arrest over time: A report from the COSTA group. Resuscitation. ISSN 0300-9572. 151, p. 67–74. doi: 10.1016/j.resuscitation.2020.03.014. Full text in Research Archive Show summary

  Background Prior research suggests that the proportion of a shockable initial rhythm in out-of-hospital cardiac arrest (OHCA) declined during the last decades. This study aims to investigate if this decline is still ongoing and explore the relationship between location of OHCA and proportion of a shockable initial rhythm as initial rhythm. Methods We calculated the proportion of patients with a shockable initial rhythm between 2006–2015 using pooled data from the COSTA-group (Copenhagen, Oslo, Stockholm, Amsterdam). Analyses were stratified according to location of OHCA (residential vs. public). Results A total of 19,054 OHCA cases were included. Overall, the total proportion of cases with a shockable initial rhythm decreased from 42% to 37% (P < 0.01) from 2006 to 2015. When stratified according to location, the proportion of cases with a shockable initial rhythm decreased for OHCAs at a residential location (34% to 27%; P = 0.03), while the proportion of a shockable initial rhythm was stable among OHCAs in public locations (59%–57%; P = 0.2). During the last years of the study period (2011–2015), the overall proportion of a shockable initial rhythm remained stable (38%–37%; P = 0.45); this was observed for both residential and public OHCA. Conclusion We found a decline in the proportion of patients with a shockable initial rhythm in OHCAs at a residential location; this decline levelled off during the second half of the study period (2011–2015). In public locations, we observed no decline in shockable initial rhythm over time.

• Brede, Jostein Rødseth; Kramer-Johansen, Jo & Rehn, Marius (2020). A needs assessment of resuscitative endovascular balloon occlusion of the aorta (REBOA) in non-traumatic out-of-hospital cardiac arrest in Norway. BMC Emergency Medicine. 20(28). doi: 10.1186/s12873-020-00324-z. Full text in Research Archive Show summary

  Introduction: Out of hospital cardiac arrest (OHCA) carries an 86% mortality rate in Norway. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a potential adjunct in management of non-traumatic cardiac arrest and is feasible in pre-hospital setting without compromising standard cardiopulmonary resuscitation (CPR). However, number of patients potentially eligible for REBOA remain unknown. In preparation for a clinical trial to investigate any benefit of pre-hospital REBOA, we sought to assess the need for REBOA in Norway as an adjunct treatment in OHCA. Methods: Retrospective observational cohort study of data from the Norwegian Cardiac Arrest Registry in the 3- year period 2016–2018. We identified number of patients potentially eligible for pre-hospital REBOA during CPR, defined by suspected non-traumatic origin, age 18–75 years, witnessed arrest, ambulance response time less than 15 min, treated by ambulance personnel and resuscitation effort over 30 min. Results: In the 3-year period, ambulance personnel resuscitated 8339 cases. Of these, a group of 720 patients (8.6%) were eligible for REBOA. Only 18% in this group achieved return of spontaneous circulation and 7% survived for 30 days or more. Conclusion: This national registry data analysis constitutes a needs assessment of REBOA in OHCA. We found that each year approximately 240 patients, or nearly 9% of ambulance treated OHCA, in Norway is potentially eligible for pre-hospital REBOA as an adjunct treatment to standard resuscitation. This needs assessment suggests that there is sufficient patient population in Norway to study REBOA as an adjunct treatment in OHCA.

• Tjelmeland, Ingvild Beathe Myrhaugen; Alm-Kruse, Kristin; Andersson, Lars-Jøran; Bratland, Ståle; Hafstad, Arne Ketil & Haug, Bjørn [Show all 14 contributors for this article] (2020). Cardiac arrest as a reportable condition: A cohort study of the first 6 years of the Norwegian out-of-hospital cardiac arrest registry. BMJ Open. 10(7), p. 1–7. doi: 10.1136/bmjopen-2020-038133. Full text in Research Archive Show summary

  Objectives The Norwegian Cardiac Arrest Registry (NorCAR) was established in 2013 when cardiac arrest became a mandatory reportable condition. The aim of this cohort study is to describe how the world’s first mandatory, population-based cardiac arrest registry evolved during its first 6 years. Setting Norway has a total population of 5.3 million inhabitants with a population density that varies considerably. All residents are assigned a unique identifier number, giving nationally approved registries access to information about all births and deaths in the country. Data in the registry are entered by data processors; public employees with close links to the emergency medical services. All data processors undergo a standardised training and meet for yearly retraining and updates. Participants All events of cardiac arrest where bystanders or healthcare professionals have started cardiopulmonary resuscitation or performed defibrillation are included into the NorCAR. Primary and secondary outcome measures Since the establishment of the registry, the number of reporting health trusts, the number of reported events and the corresponding population at risk were followed year by year. Outcome is measured as changes in inclusion rate, incidence per 100 000 inhabitants and survival to 30 days after cardiac arrest. Results In total, 14 849 cases were registered over 6 years, between 2013 and 2018. The number of health trusts reporting rose steadily from 2013. Within 3 years, all trusts reported to the registry with an increasing number of events reported; going from 1101 to 3400 per year. The prevalence of bystander cardiopulmonary resuscitation increased slightly, but the population incidence of survival did not change. Conclusion Declaring cardiac arrest as a reportable condition and close follow-up of all reporting areas is essential when building a national registry.

• Isasi, Iraia; Irusta, Unai; Aramendi, Elisabete; Ayala, Unai; Alonso, Erik & Kramer-Johansen, Jo [Show all 7 contributors for this article] (2019). A Multistage Algorithm for ECG Rhythm Analysis During Piston-Driven Mechanical Chest Compressions. IEEE Transactions on Biomedical Engineering. ISSN 0018-9294. 66(1), p. 263–272. doi: 10.1109/TBME.2018.2827304. Full text in Research Archive
• Picon, Artzai; Irusta, Unai; Alvarez-Gila, Aitor; Aramendi, Elisabete; Alonso-Atienza, Felipe & Figuera, Carlos [Show all 11 contributors for this article] (2019). Mixed convolutional and long short-term memory network for the detection of lethal ventricular arrhythmia. PLOS ONE. 14(5), p. 1–22. doi: 10.1371/journal.pone.0216756. Full text in Research Archive Show summary

  Early defibrillation by an automated external defibrillator (AED) is key for the survival of out-of-hospital cardiac arrest (OHCA) patients. ECG feature extraction and machine learning have been successfully used to detect ventricular fibrillation (VF) in AED shock decision algorithms. Recently, deep learning architectures based on 1D Convolutional Neural Networks (CNN) have been proposed for this task. This study introduces a deep learning architecture based on 1D-CNN layers and a Long Short-Term Memory (LSTM) network for the detection of VF. Two datasets were used, one from public repositories of Holter recordings captured at the onset of the arrhythmia, and a second from OHCA patients obtained minutes after the onset of the arrest. Data was partitioned patient-wise into training (80%) to design the classifiers, and test (20%) to report the results. The proposed architecture was compared to 1D-CNN only deep learners, and to a classical approach based on VF-detection features and a support vector machine (SVM) classifier. The algorithms were evaluated in terms of balanced accuracy (BAC), the unweighted mean of the sensitivity (Se) and specificity (Sp). The BAC, Se, and Sp of the architecture for 4-s ECG segments was 99.3%, 99.7%, and 98.9% for the public data, and 98.0%, 99.2%, and 96.7% for OHCA data. The proposed architecture outperformed all other classifiers by at least 0.3-points in BAC in the public data, and by 2.2-points in the OHCA data. The architecture met the 95% Sp and 90% Se requirements of the American Heart Association in both datasets for segment lengths as short as 3-s. This is, to the best of our knowledge, the most accurate VF detection algorithm to date, especially on OHCA data, and it would enable an accurate shock no shock diagnosis in a very short time.

• Berve, Per-Olav Stefferud; Irusta, Unai; Kramer-Johansen, Jo; Skålhegg, Tore; Kongsgård, Håvard Wahl & Brunborg, Cathrine [Show all 8 contributors for this article] (2019). Transthoracic impedance measured with defibrillator pads—New interpretations of signal change induced by ventilations. Journal of Clinical Medicine. 8(5). doi: 10.3390/jcm8050724. Full text in Research Archive Show summary

  Compressions during the insufflation phase of ventilations may cause severe pulmonary injury during cardiopulmonary resuscitation (CPR). Transthoracic impedance (TTI) could be used to evaluate how chest compressions are aligned with ventilations if the insufflation phase could be identified in the TTI waveform without chest compression artifacts. Therefore, the aim of this study was to determine whether and how the insufflation phase could be precisely identified during TTI. We synchronously measured TTI and airway pressure (Paw) in 21 consenting anaesthetised patients, TTI through the defibrillator pads and Paw by connecting the monitor-defibrillator’s pressure-line to the endotracheal tube filter. Volume control mode with seventeen different settings were used (5–10 ventilations/setting): Six volumes (150–800 mL) with 12 min−1 frequency, four frequencies (10, 12, 22 and 30 min−1) with 400 mL volume, and seven inspiratory times (0.5–3.5 s ) with 400 mL/10 min−1 volume/frequency. Median time differences (quartile range) between timing of expiration onset in the Paw-line (PawEO) and the TTI peak and TTI maximum downslope were measured. TTI peak and PawEO time difference was 579 (432–723) m s for 12 min−1, independent of volume, with a negative relation to frequency, and it increased linearly with inspiratory time (slope 0.47, R 2 = 0.72). PawEO and TTI maximum downslope time difference was between −69 and 84 m s for any ventilation setting (time aligned). It was independent ( R 2 &lt; 0.01) of volume, frequency and inspiratory time, with global median values of −47 (−153–65) m s , −40 (−168–68) m s and 20 (−93–128) m s , for varying volume, frequency and inspiratory time, respectively. The TTI peak is not aligned with the start of exhalation, but the TTI maximum downslope is. This knowledge could help with identifying the ideal ventilation pattern during CPR.

• Isasi, Iraia; Irusta, Unai; Elola, Andoni; Aramendi, Elisabete; Eftestøl, Trygve Christian & Kramer-Johansen, Jo [Show all 7 contributors for this article] (2019). A Robust Machine Learning Architecture for a Reliable ECG Rhythm Analysis during CPR. IEEE Engineering in Medicine and Biology Society. Conference Proceedings. ISSN 1557-170X. p. 1903–1907. doi: 10.1109/EMBC.2019.8856784. Full text in Research Archive
• Isasi, Iraia; Irusta, Unai; Rad, Ali Bahrami; Aramendi, Elisabete; Zabihi, Morteza & Eftestøl, Trygve Christian [Show all 8 contributors for this article] (2019). Automatic Cardiac Rhythm Classification With Concurrent Manual Chest Compressions. IEEE Access. 7, p. 115147–1151159. doi: 10.1109/ACCESS.2019.2935096. Full text in Research Archive Show summary

  Electrocardiogram (EKG) based classification of out-of-hospital cardiac arrest (OHCA) rhythms is important to guide treatment and to retrospectively elucidate the effects of therapy on patient response. OHCA rhythms are grouped into five categories: ventricular fibrillation (VF) and tachycardia (VT), asystole (AS), pulseless electrical activity (PEA), and pulse-generating rhythms (PR). Clinically these rhythms are grouped into broader categories like shockable (VF/VT), non-shockable (AS/PEA/PR), or organized (ORG, PEA/PR). OHCA rhythm classification is further complicated because EKGs are corrupted by cardiopulmonary resuscitation (CPR) artifacts. The objective of this study was to demonstrate a framework for automatic multiclass OHCA rhythm classification in the presence of CPR artifacts. In total, 2133 EKG segments from 272 OHCA patients were used: 580 AS, 94 PR, 953 PEA, 479 VF, and 27 VT. CPR artifacts were adaptively filtered, 93 features were computed from the stationary wavelet transform analysis, and random forests were used for classification. A repeated stratified nested cross-validation procedure was used for feature selection, parameter tuning, and model assessment. Data were partitioned patient-wise. The classifiers were evaluated using per class sensitivity, and the unweighted mean of sensitivities (UMS) as a global performance metric. Four levels of clinical detail were studied: shock/no-shock, shock/AS/ORG, VF/VT/AS/ORG, and VF/VT/AS/PEA/PR. The median UMS (interdecile range) for the 2, 3, 4, and 5-class classifiers were: 95.4% (95.1-95.6), 87.6% (87.3-88.1), 80.6% (79.3-81.8), and 71.9% (69.5-74.6), respectively. For shock/no-shock decisions sensitivities were 93.5% (93.0-93.9) and 97.2% (97.0-97.4), meeting clinical standards for artifact-free EKG. The UMS for five classes with CPR artifacts was 5.8-points below that of the best algorithms without CPR artifacts, but improved the UMS of latter by over 19-points for EKG with CPR artifacts. A robust and accurate approach for multiclass OHCA rhythm classification during CPR has been demonstrated, improving the accuracy of the current state-of-the-art methods.

• Andresen, Åke Erling Lappen; Kramer-Johansen, Jo & Kristiansen, Thomas (2019). Percutaneous vs surgical emergency cricothyroidotomy: An experimental randomized crossover study on an animal-larynx model. Acta Anaesthesiologica Scandinavica. ISSN 0001-5172. 63(10), p. 1306–1312. doi: 10.1111/aas.13447. Full text in Research Archive Show summary

  Background Airway management is a paramount clinical skill for the anaesthesiologist. The Emergency Cricothyroidotomy (EC) constitutes the final step in difficult airway algorithms securing a patent airway via a front‐of‐neck access. The main distinction among available techniques is whether the procedure is surgical and scalpel‐based or percutaneous and needle‐based. Methods In an experimental randomized crossover trial, using an animal larynx model, we compared two EC techniques; the Rapid Four Step Technique and the Melker Emergency Cricothyrotomy Kit®. We assessed time expenditure and success rates among 20 anaesthesiologists and related this to previous training, seniority and clinical experience with EC. Results All participants achieved successful airway access with both methods. Average time to successful airway access for scalpel‐based EC was 54 (±31) seconds and for percutaneous EC 89 (±38) seconds, with 35 (95% CI: 14‐57) seconds time difference, P = .003. Doctors with recent (<12 months) EC training performed better compared to the non‐training group (37 vs 61 seconds, P = .03 for scalpel‐based EC, and 65 vs 99 seconds, P = .02 for percutaneous EC). We found no differences according to clinical seniority or previous real‐life EC experience. Conclusions Our study demonstrated that anaesthesiologists achieved successful airway access on an animal experimental model with both EC methods within a reasonable time frame, but the scalpel‐based EC is performed more promptly. Recent EC training affected the time expenditure positively, while seniority and clinical EC experience did not. EC procedures should be regularly trained for.

• Isasi, Iraia; Irusta, Unai; Elola, Andoni; Aramendi, Elisabete; Ayala, Unai & Alonso, Erik [Show all 8 contributors for this article] (2019). A Machine Learning Shock Decision Algorithm for use during Piston-driven Chest Compressions. IEEE Transactions on Biomedical Engineering. ISSN 0018-9294. 66(6), p. 1752–1760. doi: 10.1109/TBME.2018.2878910. Full text in Research Archive
• Zijlstra, Jolande A; Koster, Rudolph W.; Blom, Marieke T; Lippert, Freddy K; Svensson, Leif & Herlitz, Johan [Show all 20 contributors for this article] (2018). Different defibrillation strategies in survivors after out-of-hospital cardiac arrest. Heart. ISSN 1355-6037. 104(23), p. 1929–1936. doi: 10.1136/heartjnl-2017-312622. Full text in Research Archive
• Rad, Ali Bahrami; Eftestøl, Trygve Christian; Irusta, Unai; Kvaløy, Jan Terje; Wik, Lars & Kramer-Johansen, Jo [Show all 8 contributors for this article] (2018). An automatic system for the comprehensive retrospective analysis of cardiac rhythms in resuscitation episodes. Resuscitation. ISSN 0300-9572. 122, p. 6–12. doi: 10.1016/j.resuscitation.2017.11.035. Full text in Research Archive Show summary

  AIM: An automatic resuscitation rhythm annotator (ARA) would facilitate and enhance retrospective analysis of resuscitation data, contributing to a better understanding of the interplay between therapy and patient response. The objective of this study was to define, implement, and demonstrate an ARA architecture for complete resuscitation episodes, including chest compression pauses (CC-pauses) and chest compression intervals (CC-intervals). METHODS: We analyzed 126.5h of ECG and accelerometer-based chest-compression depth data from 281 out-of-hospital cardiac arrest (OHCA) patients. Data were annotated by expert reviewers into asystole (AS), pulseless electrical activity (PEA), pulse-generating rhythm (PR), ventricular fibrillation (VF), and ventricular tachycardia (VT). Clinical pulse annotations were based on patient-charts and impedance measurements. An ARA was developed for CC-pauses, and was used in combination with a chest compression artefact removal filter during CC-intervals. The performance of the ARA was assessed in terms of the unweighted mean of sensitivities (UMS). RESULTS: The UMS of the ARA were 75.0% during CC-pauses and 52.5% during CC-intervals, 55-points and 32.5-points over a random guess (20% for five categories). Filtering increased the UMS during CC-intervals by 5.2-points. Sensitivities for AS, PEA, PR, VF, and VT were 66.8%, 55.8%, 86.5%, 82.1% and 83.8% during CC-pauses; and 51.1%, 34.1%, 58.7%, 86.4%, and 32.1% during CC-intervals. CONCLUSIONS: A general ARA architecture was defined and demonstrated on a comprehensive OHCA dataset. Results showed that semi-automatic resuscitation rhythm annotation, which may involve further revision/correction by clinicians for quality assurance, is feasible. The performance (UMS) dropped significantly during CC-intervals and sensitivity was lowest for PEA.

• Skaare, Christiane; CALISCH, TOR EINAR; Sæter, Erik; Rajka, Thomas; Boldingh, Anne Marthe & Nakstad, Britt [Show all 9 contributors for this article] (2018). Implementation and effectiveness of a video-based debriefing programme for neonatal resuscitation. Acta Anaesthesiologica Scandinavica. ISSN 0001-5172. 62(3), p. 394–403. doi: 10.1111/aas.13050. Full text in Research Archive Show summary

  Background: Approximately 5%–10% of newly born babies need intervention to assist transition from intra‐ to extrauterine life. All providers in the delivery ward are trained in neonatal resuscitation, but without clinical experience or exposure, training competency is transient with a decline in skills within a few months. The aim of this study was to evaluate whether neonatal resuscitations skills and team performance would improve after implementation of video‐assisted, performance‐focused debriefings. Methods: We installed motion‐activated video cameras in every resuscitation bay capturing consecutive compromised neonates. The videos were used in debriefings led by two experienced facilitators, focusing on guideline adherence and non‐technical skills. A modification of Neonatal Resuscitation Performance Evaluation (NRPE) was used to score team performance and procedural skills during a 7 month study period (2.5, 2.5 and 2 months pre‐, peri‐ and post‐implementation) (median score with 95% confidence interval). Results: We compared 74 resuscitation events pre‐implementation to 45 events post‐implementation. NRPE‐score improved from 77% (75, 81) to 89% (86, 93), P < 0.001. Specifically, the sub‐categories “group function/communication”, “preparation and initial steps”, and “positive pressure ventilation” improved (P < 0.005). Adequate positive pressure ventilation improved from 43% to 64% (P = 0.03), and pauses during initial ventilation decreased from 20% to 0% (P = 0.02). Proportion of infants with heart rate > 100 bpm at 2 min improved from 71% pre‐ vs. 82% (P = 0.22) post‐implementation. Conclusion: Implementation of video‐assisted, performance‐focused debriefings improved adherence to best practice guidelines for neonatal resuscitation skill and team performance.

• Isasi, Iraia; Rad, Ali Bahrami; Irusta, Unai; Zabihi, Morteza; Aramendi, Elisabete & Eftestøl, Trygve Christian [Show all 8 contributors for this article] (2018). ECG Rhythm Analysis during Manual Chest compressions using an Artefact Removal Filter and Random Forest Classifiers. Computing in cardiology. ISSN 2325-8861. 45. doi: 10.22489/CinC.2018.202. Full text in Research Archive
• Steinberg, Mikkel Torp; Olsen, Jan Åge; Eriksen, Morten; Neset, Andres; Norseng, Per Andreas & Kramer-Johansen, Jo [Show all 8 contributors for this article] (2018). Haemodynamic outcomes during piston-based mechanical CPR with or without active decompression in a porcine model of cardiac arrest. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. 26:31, p. 1–10. doi: 10.1186/s13049-018-0496-z. Full text in Research Archive Show summary

  Background Experimental active compression-decompression (ACD) CPR is associated with increased haemodynamic outcomes compared to standard mechanical chest compressions. Since no clinically available mechanical chest compression device is capable of ACD-CPR, we modified the LUCAS 2 (Physio-Control, Lund, Sweden) to deliver ACD-CPR, hypothesising it would improve haemodynamic outcomes compared with standard LUCAS CPR on pigs with cardiac arrest. Methods The modified LUCAS delivering 5 cm compressions with or without 2 cm active decompression above anatomical chest level was studied in a randomized crossover design on 19 Norwegian domestic pigs. VF was electrically induced and untreated for 2 min. Each pig received ACD-CPR and standard mechanical CPR in three 180-s. phases. We measured aortic, right atrial, coronary perfusion, intracranial and oesophageal pressure, cerebral and carotid blood flow and cardiac output. Two-sided paired samples t-test was used for continuous parametric data and Wilcoxon test for non-parametric data. P < 0.05 was considered significant. Results Due to injuries/device failure, the experimental protocol was completed in nine of 19 pigs. Cardiac output (l/min, median, (25, 75-percentiles): 1.5 (1.1, 1.7) vs. 1.1 (0.8, 1.5), p < 0.01), cerebral blood flow (AU, 297 vs. 253, mean difference: 44, 95% CI; 14–74, p = 0.01), and carotid blood flow (l/min, median, (25, 75-percentiles): 97 (70, 106) vs. 83 (57, 94), p < 0.01) were higher during ACD-CPR compared to standard mechanical CPR. Coronary perfusion pressure (CPP) trended towards higher in end decompression phase. Conclusion Cardiac output and brain blood flow improved with mechanical ACD-CPR and CPP trended towards higher during end-diastole compared to standard LUCAS CPR.

• Isasi, Iraia; Irusta, Unai; Aramendi, Elisabete; Ayala, Unai; Alonso, Erik & Kramer-Johansen, Jo [Show all 7 contributors for this article] (2018). An Accurate Shock Advise Algorithm for Use During Piston-Driven Chest Compressions. Computing in cardiology. ISSN 2325-8861. 45. doi: 10.22489/CinC.2018.20. Full text in Research Archive
• Skaare, Christiane; Boldingh, Anne Marthe; Kramer-Johansen, Jo; CALISCH, TOR EINAR; Nakstad, Britt & Nadkarni, Vinay [Show all 8 contributors for this article] (2018). Video performance-debriefings and ventilation-refreshers improve quality of neonatal resuscitation. Resuscitation. ISSN 0300-9572. p. 1–7. doi: 10.1016/j.resuscitation.2018.07.013. Full text in Research Archive Show summary

  Aim: Providers caring for newly born infants require skills and knowledge to initiate prompt and effective positive pressure ventilation (PPV) if the newborn does not breathe spontaneously after birth. We hypothesized implementation of high frequency/short duration deliberate practice training and post event video-based debriefings would improve process of care and decreases time to effective spontaneous respiration. Methods: Pre- and post-interventional quality study performed at two Norwegian university hospitals. All newborns receiving PPV were prospectively video-recorded, and initial performance data guided the development of educational interventions. A priori primary outcome was changed from process of care using the Neonatal Resuscitation Performance Evaluation (NRPE) score to time to effective spontaneous respiration as the NRPE score could only be obtained from one site due to lack of staff resources. Results: Over 12 months, 297 PPV-Refreshers and 52 performance debriefings were completed with 227 unique providers attending a PPV-Refresher and 93 unique providers completed a debriefing. We compared 102 PPV-events pre- to 160 PPV-events post-bundle implementation. The time to effective spontaneous respiration decreased from median (95% confidence interval) 196 (140–237) to 144 (120–163) s, p = 0.010. The NRPE-score increased significantly from median 77% (75–81) pre- to 89% (86–92) post-implementation, p < 0.001. There were no significant differences in time to heart rate >100 beats/min or number of newborns transferred to intensive care. Conclusion: High frequency/short duration deliberate practice PPV psychomotor training combined with performance-focused team debriefings using video recordings of actual resuscitations may improve time to effective spontaneous breathing and adherence to guidelines during real neonatal resuscitations.

• Ringh, M.; Hollenberg, J.; Palsgaard-Moeller, T.; Svensson, L.; Rosenqvist, Mikael & Lippert, FK [Show all 20 contributors for this article] (2018). The challenges and possibilities of public access defibrillation. Journal of Internal Medicine. ISSN 0954-6820. 283(3), p. 238–256. doi: 10.1111/joim.12730. Full text in Research Archive Show summary

  Out‐of‐hospital cardiac arrest (OHCA) is a major health problem that affects approximately four hundred and thousand patients annually in the United States alone. It is a major challenge for the emergency medical system as decreased survival rates are directly proportional to the time delay from collapse to defibrillation. Historically, defibrillation has only been performed by physicians and in‐hospital. With the development of automated external defibrillators (AEDs), rapid defibrillation by nonmedical professionals and subsequently by trained or untrained lay bystanders has become possible. Much hope has been put to the concept of Public Access Defibrillation with a massive dissemination of public available AEDs throughout most Western countries. Accordingly, current guidelines recommend that AEDs should be deployed in places with a high likelihood of OHCA. Despite these efforts, AED use is in most settings anecdotal with little effect on overall OHCA survival. The major reasons for low use of public AEDs are that most OHCAs take place outside high incidence sites of cardiac arrest and that most OHCAs take place in residential settings, currently defined as not suitable for Public Access Defibrillation. However, the use of new technology for identification and recruitment of lay bystanders and nearby AEDs to the scene of the cardiac arrest as well as new methods for strategic AED placement redefines and challenges the current concept and definitions of Public Access Defibrillation. Existing evidence of Public Access Defibrillation and knowledge gaps and future directions to improve outcomes for OHCA are discussed. In addition, a new definition of the different levels of Public Access Defibrillation is offered as well as new strategies for increasing AED use in the society. This article has been accepted and published in Journal of Internal Medicine.

• Hardeland, Camilla; Skaare, Christiane; Kramer-Johansen, Jo; Birkenes, Tonje Søraas; Myklebust, Helge & Hansen, Andreas [Show all 8 contributors for this article] (2017). Targeted simulation and education to improve cardiac arrest recognition and telephone assisted CPR in an emergency medical communication centre. Resuscitation. ISSN 0300-9572. 114, p. 21–26. doi: 10.1016/j.resuscitation.2017.02.013. Full text in Research Archive
• Niles, Dana E.; Cines, Courtney; Insley, Elena; Foglia, Elizabeth E; Elci, Okan U. & Skaare, Christiane [Show all 11 contributors for this article] (2017). Incidence and characteristics of positive pressure ventilation delivered to newborns in a US tertiary academic hospital. Resuscitation. ISSN 0300-9572. 115, p. 102–109. doi: 10.1016/j.resuscitation.2017.03.035. Full text in Research Archive
• Niles, Dana E.; Nishisaki, Akira; Sutton, Robert M.; Elci, Okan U.; Meaney, Peter A. & O'Connor, Kathleen A. [Show all 10 contributors for this article] (2017). Improved retention of chest compression psychomotor skills with brief "rolling refresher" training. Simulation in Healthcare: The Journal of the Society for Simulation in Healthcare. ISSN 1559-2332. 12(4), p. 213–219. doi: 10.1097/SIH.0000000000000228. Full text in Research Archive
• Isasi, Iraia; Irusta, Unai; Aramendi, Elisabete; Ayala, Unai; Alonso, Erik & Kramer-Johansen, Jo [Show all 7 contributors for this article] (2017). Removing Piston-driven Mechanical Chest Compression Artefacts from the ECG. Computing in cardiology. ISSN 2325-8861. 44. doi: 10.22489/CinC.2017.009-115. Full text in Research Archive
• Rad, Ali Bahrami; Eftestøl, Trygve Christian; Engan, Kjersti; Irusta, Unai; Kvaløy, Jan Terje & Kramer-Johansen, Jo [Show all 8 contributors for this article] (2017). ECG-Based classification of resuscitation cardiac rhythms for retrospective data analysis. IEEE Transactions on Biomedical Engineering. ISSN 0018-9294. 64(10), p. 2411–2418. doi: 10.1109/TBME.2017.2688380. Full text in Research Archive
• Skaare, Christiane; Boldingh, Anne Marthe; Nakstad, Britt; CALISCH, TOR EINAR; Niles, Dana E. & Nadkarni, Vinay M. [Show all 8 contributors for this article] (2016). Ventilation fraction during the first 30s of neonatal resuscitation. Resuscitation. ISSN 0300-9572. 107, p. 25–30. doi: 10.1016/j.resuscitation.2016.07.231. Full text in Research Archive
• Nestaas, Sverre; STENSÆTH, KNUT-HAAKON; Rosseland, Vigdis & Kramer-Johansen, Jo (2016). Radiological assessment of chest compression point and achievable compression depth in cardiac patients. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. 24(54). doi: 10.1186/s13049-016-0245-0. Full text in Research Archive Show summary

  Background Using magnetic resonance imaging (MRI) to relate cardiovascular structures to surface anatomy in a population relevant to cardiac arrest victims, relate the external thoracic anterior-posterior (AP) diameter (APEXTERNAL) and blood-filled structures to recommended chest compression depths, and define an optimal compression point (OCP). Methods MRI axial scans of referred patients were analysed. We defined origo as the skin surface of the centre of sternum in the internipple line. The blood-filled structures beneath origo were identified and the sum of their inner diameters (APBLOOD) and APEXTERNAL were measured. We defined OCP based on the image with maximum compressible left and right ventricle and where LVOT was not present. We measured the distance from origo to OCP. Results Consecutive patients, mean (SD), age 52 (17) years, 110 (76 %) males, were categorized: cardiac disease (n = 74), aortic disease (n = 13), no findings/study patient (included in another study) (n = 57). The structure LVOT/aortic valve (AV)/aortic root was present in 46 % of patients with cardiac disease vs. 19 % of patients with no findings. APEXTERNAL for males and females was 25 (2) cm and 22 (2) cm, and APBLOOD 6.5 cm (2) and 4.7 cm (2), respectively. Distance from origo to OCP was 32 (11) mm to the left and 16 (21) mm caudally. Discussion LVOT/AV/aortic root was present beneath the origo in almost half the patients with cardiac disease. Recommended chest compression depths exceeded the anterior-posterior diameter of blood-filled structures in more than half of the females. OCP was found 3 cm left of the origo. Conclusions Based on our study, individualized compression point and depth could be further studied in a prospective, clinical study.

• Alm-Kruse, Kristin; Kramer-Johansen, Jo & Bogstrand, Stig Tore (2016). Registrerer få hjertestanser. Sykepleien Forskning. ISSN 1890-2936. doi: 10.4220/Sykepleienf.2016.58523. Full text in Research Archive Show summary

  Bakgrunn: Studier fra andre land viser stor variasjon i forekomst og overlevelse etter hjerte- lunge-redning (HLR) på intensivavdelinger. Det foreligger få studier på dette området i Norge. Hensikt: Å kartlegge forekomst og overlevelse etter HLR samt få oversikt over hvordan HLR ble registrert. Metode: Vi foretok en tverrsnittsstudie av 14 intensivavdelinger på Oslo universitetssykehus gjennom hele 2013. Pasienter med diagnoser og prosedyrekoder for hjertestans, ventrikkelarytmier og HLR ble identifisert i pasientadministrative systemer. Vi inkluderte alle tilfellene der diagnoser og prosedyrekoder ble bekreftet i pasientjournalen, i studieutvalget. Deretter sammenliknet vi med de tilfellene som var registrert i det interne kvalitetsregisteret for hjertestans. Resultat: Blant 15 101 intensivinnleggelser fant vi 117 (0,8 prosent) tilfeller av HLR fordelt på 99 pasienter. Av 91 voksne (> 18 år) var 64 (70 prosent) menn. Gjennomsnittsalderen var 63 år. Antall voksne som overlevde til utskrivning fra sykehuset var 44 (48 prosent). Overlevelsen for kvinner var signifikant lavere enn for menn: 8 (30 prosent) kvinner overlevde mot 36 (56 prosent) menn, (p = 0,023). Kun 32 (32 prosent) av alle pasientene var registrert i vårt interne hjertestansregister. Konklusjon: Knapt én av hundre intensivinnleggelser fikk HLR. Halvparten av pasientene overlevde til utskrivning etter HLR. En tredjedel av disse pasientene var registrert i det interne hjertestansregisteret. Forekomst og registrering av HLR er lav, mens overlevelsen er høy sammenliknet med tilsvarende studier fra andre land.

• Grusd, Eystein & Kramer-Johansen, Jo (2016). Does the Norwegian emergency medical dispatch classification as non-urgent predict no need for pre-hospital medical treatment? An observational study. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. 24(65). doi: 10.1186/s13049-016-0258-8. Full text in Research Archive Show summary

  Background: The number of ambulance call-outs in Norway is increasing owing to societal changes and increased demand from the public. Together with improved but more expensive education of ambulance staff, this leads to increased costs and staffing shortages. We wanted to study whether the current dispatch triage tools could reliably identify patients who only required transport, and not pre-hospital medical care. This could allow selection of such patients for designated transport units, freeing up highly trained ambulance staff to attend patients in greater need. Methods: A cross-sectional observational study was used, drawing on all electronic and paper records in our ambulance service from four random days in 2012. The patients were classified into acuity groups, based on Emergency Medical Dispatch codes, and pre-hospital interventions were extracted from the Patient Report Forms. Results: Of the 1489 ambulance call-outs included in this study, 82 PRFs (5 %) were missing. A highly significant association was found between acuity group and recorded pre-hospital intervention (p ≤ 0.001). We found no correlation between gender, distance to hospital, age and pre-hospital interventions. Ambulances staffed by paramedics performed more interventions (234/917, 26 %) than those with emergency medical technicians (42/282, 15 %). The strongest predictor for needing pre-hospital interventions was found to be the emergency medical dispatch acuity descriptor. Discussion: This study has demonstrated that the Norwegian dispatch system is able to correctly identify patients who do not need pre-hospital interventions. Patients with a low acuity code had a very low level of pre-hospital interventions. Evaluation of adherence to protocol in the Emergency Medical Dispatch is not possible due to the inherent need for medical experience in the triage process. Conclusions: This study validates the Norwegian dispatch tool (Norwegian index) as a predictor of patients who do not need pre-hospital interventions.

• Aramendi, Elisabete; Irusta, U; Ayala, Unai; Naas, Henning; Kramer-Johansen, Jo & Eftestøl, Trygve Christian (2016). Filtering mechanical chest compression artefacts from out-of-hospital cardiac arrest data. Resuscitation. ISSN 0300-9572. 98, p. 41–47. doi: 10.1016/j.resuscitation.2015.10.012. Full text in Research Archive
• Rad, Ali Bahrami; Engan, Kjersti; Katsaggelos, Aggelos K.; Kvaløy, Jan Terje; Wik, Lars & Kramer-Johansen, Jo [Show all 8 contributors for this article] (2016). Automatic cardiac rhythm interpretation during resuscitation. Resuscitation. ISSN 0300-9572. 102, p. 44–50. doi: 10.1016/j.resuscitation.2016.01.015. Full text in Research Archive

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• Kelpanides, Inga Katherina; Katzenschlager, Stephan; Tjelmeland, Ingvild Beathe Myrhaugen; Kramer-Johansen, Jo; Bossaert, Leo & Maurer, Holger [Show all 38 contributors for this article] (2025). Cardiac arrest in children: A Europe-wide epidemiological study on out-of-hospital cardiac arrest in children. A protocol for a subgroup analysis of the European registry of cardiac arrest THREE study. doi: 10.1016/j.resplu.2025.101081. Full text in Research Archive
• Alm-Kruse, Kristin & Kramer-Johansen, Jo (2025). Addressing Data Misinterpretation in Recent Meta-Analysis. Journal of Intensive Care Medicine. ISSN 0885-0666. 40(6), p. 691–692. doi: 10.1177/08850666251341255. Full text in Research Archive
• Steenstrup, Sophie; Kramer-Johansen, Jo & Berge, Hilde Moseby (2024). Saving lives together in sport, part one: Initiating voluntary training in cardiopulmonary resuscitation with the use of automated external defibrillators in Norwegian football clubs. Full text in Research Archive
• Steenstrup, Sophie; Kramer-Johansen, Jo & Berge, Hilde Moseby (2024). Saving lives together in sport, part two: A pilot study to increase the number and availability of automated external defibrillators at Norwegian football arenas. Full text in Research Archive
• Jamtli, Bjørn; Hardeland, Camilla; Kramer-Johansen, Jo & Hov, Maren Ranhoff (2024). Hjerneslag - en utfordring for AMK. Full text in Research Archive
• Harring, Astrid Karina; Tjelmeland, Ingvild Beathe Myrhaugen & Kramer-Johansen, Jo (2024). Kritisk informasjon: HLR- i Kjernejournal. Full text in Research Archive
• Katzenschlager, Stephan; Kelpanides, Inga Katherina; Skogvoll, Eirik; Grindheim, Guro; Wnent, Jan & Popp, Erik [Show all 10 contributors for this article] (2023). Paediatric out-of-hospital cardiac arrest: Time to update registries? Critical Care. ISSN 1364-8535. 27(1). doi: 10.1186/s13054-023-04582-8. Full text in Research Archive
• Jamtli, Bjørn; Hov, Maren Ranhoff; Jørgensen, Trine Møgster; Kramer-Johansen, Jo; Ihle-Hansen, Hege & Sandset, Else Charlotte [Show all 7 contributors for this article] (2023). Emergency medical communication center assessment of suspected and verified stroke patients. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. 31(1). doi: 10.1186/s13049-023-01100-1. Full text in Research Archive
• Eftestøl, Trygve Christian; Hognestad, Mari; Søndeland, Sander A.; Rad, Ali Bahrami; Aramendi, Elisabete & Wik, Lars [Show all 7 contributors for this article] (2023). A Convolutional Neural Network Approach for Interpreting Cardiac Rhythms from Resuscitation of Cardiac Arrest Patients. Full text in Research Archive
• Harring, Astrid Karina V.; Tjelmeland, Ingvild Beathe Myrhaugen & Kramer-Johansen, Jo (2023). HLR til pasienter med «HLR minus». Ambulanseforum. ISSN 0800-6423. Full text in Research Archive
• Bugge, Helge Fagerheim; Guterud, Mona; Bache, Kristi Cecilie Grønvold; Braarud, Anne-Cathrine; Eriksen, Erik & Fremstad, Kjell Otto [Show all 15 contributors for this article] (2022). Paramedic Norwegian Acute Stroke Prehospital Project (ParaNASPP) study protocol: a stepped wedge randomised trial of stroke screening using the National Institutes of Health Stroke Scale in the ambulance. Trials. 23(1). doi: 10.1186/s13063-022-06006-4. Full text in Research Archive Show summary

  Background: Less than 50% of stroke patients in Norway reach hospital within 4 h of symptom onset. Early prehospital identification of stroke and triage to the right level of care may result in more patients receiving acute treatment. Quality of communication between paramedics and the stroke centre directly affects prehospital on-scene time, emphasising this as a key factor to reduce prehospital delay. Prehospital stroke scales are developed for quick and easy identification of stroke, but have poor sensitivity and specificity compared to an in-hospital assessment with the National Institutes of Health Stroke Scale (NIHSS). The aim of the Paramedic Norwegian Acute Stroke Prehospital Project (ParaNASPP) is to assess whether a structured learning program, prehospital NIHSS and a mobile application facilitating communication with the stroke physician may improve triage of acute stroke patients. Methods: A stepped wedge cluster randomised controlled intervention design will be used in this trial in Oslo, Norway. Paramedics at five ambulance stations will enrol adult patients with suspected stroke within 24 h of symptom onset. All paramedics will begin in a control phase with standard procedures. Through an e-learning program and practical training, a random and sequential switch to the intervention phase takes place. A mobile application for NIHSS scoring, including vital patient information for treatment decisions, transferring data from paramedics to the on-call stroke physician at the Stroke Unit at Oslo University Hospital, will be provided for the intervention. The primary outcome measure is positive predictive value (PPV) for prehospital identification of patients with acute stroke defined as the proportion of patients accepted for stroke evaluation and discharged with a final stroke diagnosis. One thousand three hundred patients provide a 50% surplus to the 808 patients needed for 80% power to detect a 10% increase in PPV. Discussion: Structured and digital communication using a common scale like NIHSS may result in increased probability for better identification of stroke patients and less stroke mimics delivered to a stroke team for acute diagnostics and treatment in our population.

• Alm-Kruse, Kristin; Tjelmeland, Ingvild Beathe Myrhaugen; Reiner, Andrew Henry & Kramer-Johansen, Jo (2022). The use of primary healthcare on the day of out-of-hospital cardiac arrest -and the association with 30-days survival. Resuscitation. ISSN 0300-9572. 175, p. S11–S11. doi: 10.1016/S0300-9572(22)00383-5. Full text in Research Archive
• Harring, Astrid Karina V.; Kramer-Johansen, Jo & Tjelmeland, Ingvild B M (2021). Comparing survival and neurological outcome of the elderly suffering out-of-hospital cardiac arrest at home and in healthcare institutions. Full text in Research Archive
• Eftestøl, Trygve Christian; Stokka, Svein Erik; Kvaløy, Jan Terje; Rad, Ali Bahrami; Irusta, Unai & Aramendi, Elisabete [Show all 11 contributors for this article] (2020). A probabilistic function to model the relationship between quality of chest compressions and the physiological response for patients in cardiac arrest. Full text in Research Archive
• Harring, Astrid Karina; Tjelmeland, Ingvild B. & Kramer-Johansen, Jo (2020). Resuscitation of the elderly in Norwegian healthcare institutions: Why does EMS withhold or withdraw CPR? Full text in Research Archive
• Harring, Astrid Karina; Tjelmeland, Ingvild B. & Kramer-Johansen, Jo (2020). Survival and outcome after out of hospital cardiac arrests in the elderly in Norwegian healthcare institutions. Full text in Research Archive
• Bjørshol, Conrad Arnfinn & Kramer-Johansen, Jo (2020). Survival and neurological outcome: Search for a low-hanging fruit. Resuscitation. ISSN 0300-9572. 148, p. 269–270. doi: 10.1016/j.resuscitation.2020.01.012. Full text in Research Archive
• Tjelmeland, Ingvild Beathe Myrhaugen; Larsen, Morten; Skogvoll, Eirik & Kramer-Johansen, Jo (2019). What is the real incidence of out-of-hospital cardiac arrest (OHCA) in Norway. Full text in Research Archive
• Bjørshol, Conrad Arnfinn; Jamtli, Bjørn; Kramer-Johansen, Jo; Myklebust, Helge; Olsen, Steinar & Nordseth, Trond [Show all 10 contributors for this article] (2019). Sammen redder vi liv. 139(12), p. 1142–1144. doi: 10.4045/tidsskr.19.0128. Full text in Research Archive
• Hardeland, Camilla; Claesson, Andreas; Blomberg, Stig Nikolaj Fasmer; Folke, Fredrik; Hollenberg, Jacob & Kramer-Johansen, Jo [Show all 13 contributors for this article] (2019). Differences in out-of-hospital cardiac arrest emergency dispatch recognition and dispatcher assisted cpr instructions – a Scandinavian multicentre study. Resuscitation. ISSN 0300-9572. Full text in Research Archive
• Gilbert, mads; Wisborg, Torben; Steen-Hansen, Jon Erik; Tjelmeland, Ingvild; Kramer-Johansen, Jo & Bakke, Håkon Kvåle (2018). Folk tar ansvar, ikke selfier! Full text in Research Archive
• Isern, Cecilie Benedicte; Tjelmeland, Ingvild Beathe Myrhaugen; Alm-Kruse, Kristin; Berge, Eivind; Kramer-Johansen, Jo & Berge, Hilde Moseby (2018). Forekomst av hjertestans i forbindelse med trening - en sammenligning av funn fra media og Hjertestansregisteret. Full text in Research Archive
• Isern, Cecilie Benedicte; Tjelmeland, Ingvild Beathe Myrhaugen; Kramer-Johansen, Jo & Berge, Hilde Moseby (2018). Is media search a reliable source when investigating the incidence of sports-related out-of-hospital cardiac arrest? Full text in Research Archive
• Alm-Kruse, Kristin; Sunde, Kjetil; Sørensen, Gro; Andersen, Geir Øystein; Osbakk, Svein Are & Kramer-Johansen, Jo (2018). Outcome in potential candidates for extracorporeal cardiopulmonary resuscitation after refractory out-of-hospital cardiac arrest treated with conventional advanced life support. Resuscitation. ISSN 0300-9572. 130, p. e22–e22. doi: 10.1016/j.resuscitation.2018.07.352. Full text in Research Archive
• Eftestøl, Trygve Christian; Stokka, Svein Erik; Kvaløy, Jan Terje; Rad, Ali Bahrami; Irusta, Unai & Aramendi, Elisabete [Show all 11 contributors for this article] (2018). A machine learning approach to model a probabilistic relationship between parameters reflecting quality of chest compressions and physiological response during out-of-hospital cardiopulmonary resuscitation. Full text in Research Archive
• Tjelmeland, Ingvild; Hardeland, Camilla; Mydske-Earl, Kristine; Bakkelund, Karin Elvenes; Johnsen, Knut Roar & Skogvoll, Eirik [Show all 7 contributors for this article] (2018). How to find all out-of-hospital cardiac arrests (OHCA) that fill the inclusion criteria in the Norwegian cardiac arrest registry. Resuscitation. ISSN 0300-9572. 130, p. e17–e17. doi: 10.1016/j.resuscitation.2018.07.340. Full text in Research Archive
• Isern, Cecilie Benedicte; Tjelmeland, Ingvild Beathe Myrhaugen; Kramer-Johansen, Jo & Berge, Hilde Moseby (2018). Is media search a reliable source when investigating the incidence of sports-related out-of-hospital cardiac arrest? Resuscitation. ISSN 0300-9572. 130, p. e95–e96. Full text in Research Archive
• Isern, Cecilie Benedicte; Berge, Hilde Moseby; Kramer-Johansen, Jo & Berge, Eivind (2017). How to increase knowledge about sport-related sudden cardiac arrest in Norway. Full text in Research Archive
• Isern, Cecilie Benedicte; Berge, Hilde Moseby & Kramer-Johansen, Jo (2025). Sudden Cardiac Arrest in Young Norwegians. Assessing the role of Exercise and Implications for Prevention Strategies. Universitetet i Oslo. ISSN 9788234807114. Full text in Research Archive Show summary

  Cardiac arrests in young individuals profoundly affects patients, their family, friends, and communities. These incidents often attract media attention, resulting in prompt calls for preventive measures and potentially fostering fear of exercise in the public. Evaluation of preventive measures as screening requires consideration of the magnitude of the condition (included incidence, mortality and morbidity), assessment of the natural history of the condition, potential for detection trough screening and consequences of screening outcomes.(4, 5) By utilizing the enhanced knowledge on sudden cardiac arrest (SCA) in young Norwegians (papers I-III), this thesis evaluates prevention strategies and discuss SCA risk associated with exercise-habits from a public health perspective. Data collection employed a comprehensive, multi-source approach, integrating insights from the Norwegian Cardiac Arrest Registry (NorCAR), questionnaires, systematic media search, medical records and autopsy reports. Access to the Norwegian Cardiac Arrest Registry (NorCAR), provided a unique data quality. However, NorCAR lacked validated data on exercise-related events. In paper I, we found an SCA incidence of 7.8 per 100,000 person-years, with 10% (0.8 per 100000 person-years) exercise-related SCA. Almost two thirds of respondents (59%) reported regular exercise prior to SCA. Paper II revealed a high prevalence of risk factors (74%) and CVD symptoms (78% of survivors) prior to SCA. Symptoms occurred both during rest/everyday activity and exercise. Ischemic heart disease (IHD) was the most frequent etiology overall, while no identifiable cause classified as sudden arrhythmic death syndrome (SADS) was predominant ≤35 years. No statistically significant difference emerged between exercisers and non-exercisers. Paper III reported reduced health related quality of life (HRQoL) in survivors compared to an age- and gender matched population. There was no statistically significant difference between survivors who performed < or ≥ 5 hours of exercise / week. However, within the group of regular exercisers, we found statistical significantly higher SF-36 summary scores within the group of high-volume exercisers. Findings from paper I-III affirm SCA in the young as an important health problem, with a high potential for positive screening results. The high prevalence of SADS challenges identification of individuals at risk, whereas a high prevalence of IHD suggest a potential for prevention and treatment. Alternative preventive measures, including symptoms awareness and increased availability of automatic external defibrillators (AEDs), emerge as vital prevention strategies. Secondary prevention has the advantage of benefitting all individuals susceptible of SCA, regardless of an established CVD diagnosis. Following the confirmation of IHD as the dominating SCA etiology, the public should be reassured of the powerful effect of exercise in both primary and secondary prevention of disease.

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