Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (1,203 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
Occurrence of heart arrest in an individual when there is no immediate access to medical personnel or equipment.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Cardiac Arrest, Out-of-Hospital; Cardiac Arrests, Out-of-Hospital; Out of Hospital Cardiac Arrest; Out-of-Hospital Cardiac Arrests; Out-of-Hospital Heart Arrest; Heart Arrest, Out-of-Hospital; Heart Arrests, Out-of-Hospital; Out of Hospital Heart Arrest.
Where it fits in the MeSH classification
- Broader topics
- Heart Arrest
Research landscape
PubMed indexes 8,958 records tagged with the MeSH heading “Out-of-Hospital Cardiac Arrest” (counts retrieved 2026-10-29). 4,575 of them (51.1%) were published from 2020 onward, and the busiest period so far is 2020 onward with 4,575 records.
Reviews account for 975 records (10.9%) and meta-analyses for 291. Randomized controlled trials number 536 (6.0%) as a share of all records on the topic.
Show the data
| Period | Records |
|---|---|
| through 1999 | 0 |
| 2000-2009 | 3 |
| 2010-2019 | 4,521 |
| 2020 onward | 4,575 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 975 | 10.9% |
| Meta-analyses | 291 | 3.2% |
| Randomized controlled trials | 536 | 6.0% |
Method: PubMed query "Out-of-Hospital Cardiac Arrest"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-29.
Reading the evidence in cardiovascular medicine
Cardiovascular medicine has an unusually large body of randomized trials, so the type of outcome matters: hard clinical events such as death, heart attack and stroke carry more weight than changes in blood pressure, cholesterol or imaging markers that only predict risk. Observational studies can show associations but are confounded by age, lifestyle and other illness. Check whether a result is about prevention or treatment, the baseline risk of participants, and the absolute rather than only the relative size of any benefit.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Temporal Patterns in Out-of-Hospital Cardiac Arrest Incidence and Outcome | 2025 | Research article Design not recorded in structured metadata | 16 | cc by PMID 40668576 · DOI · PMC12268528 |
| Sedation and analgesia in post-cardiac arrest care: a post hoc analysis of the TTM2 trial | 2025 | Randomized controlled trial Design not recorded in structured metadata | 9 | cc by PMID 40528173 · DOI · PMC12175406 |
| Escalating vs Fixed Energy Defibrillation in Out-of-Hospital Cardiac Arrest Ventricular Fibrillation | 2025 | Research article Design not recorded in structured metadata | 6 | cc by PMID 40299385 · DOI · PMC12042058 |
| Bleeding complications in patients with out-of-hospital cardiac arrest treated with cangrelor and oral P2Y12 inhibitors | 2026 | Research article Design not recorded in structured metadata | 5 | cc by PMID 40479494 · DOI · PMC13123695 |
Temporal Patterns in Out-of-Hospital Cardiac Arrest Incidence and Outcome [1]
Abstract reading summary — source excerpts
- Opening excerpt
- ImportanceIncidence and outcome of out-of-hospital cardiac arrest (OHCA) have implications for public health and community strategies to reduce risk and improve resuscitation.
- Closing excerpt
- Survival improved over time overall and according to presenting rhythm, corresponding to favorable trends in community responder, prehospital, and hospital care.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (287 words)
ImportanceIncidence and outcome of out-of-hospital cardiac arrest (OHCA) have implications for public health and community strategies to reduce risk and improve resuscitation.ObjectiveTo examine temporal patterns in OHCA incidence and outcome.Design, setting, and participantsThis was a retrospective cohort investigation conducted in King County, Washington, between 2001 and 2020. Adults with OHCA treated by emergency medical services (EMS) were included in the analysis. Study data were analyzed from May 2024 to April 2025.ExposuresIncidence and clinical outcome of OHCA.Main outcomes and measuresAnnual incidence was calculated per 100 000 person-years and stratified by sex, age group (ResultsThere were 25 118 individuals (median [IQR] age, 65 [53-78] years; 15 994 male [63.7%]) with OHCA treated by EMS during 30 884 504 person-years; survival was 17.7%. Overall incidence was 81.3 per 100 000 person-years, 20.9 for shockable and 59.8 for nonshockable OHCA. There was no evidence of linear temporal change in overall incidence: 88.7 in 2001, 82.1 in 2020 (AAC, -0.5%; 95% CI, -0.9% to 0%). However, temporal patterns depended on rhythm and demographic characteristics. For example, shockable rhythm incidence declined (28.6 in 2001 and 17.9 in 2020; AAC, -2.3%; 95% CI, -2.9% to -1.5%), but change was null among nonshockable arrest (59.8 in 2001 and 63.7 in 2020; AAC, 0.3%; 95% CI, -0.1% to 0.8%). Overall survival to hospital discharge improved over time: 14.7% (859 of 5847 individuals; 2001-2005), 17.4% (1024 of 5885 individuals; 2006-2010), 19.3% (1232 of 6376 individuals; 2011-2015), and 18.9% (1322 of 7010; 2016-2020; P Conclusions and relevanceResults suggest that the overall OHCA incidence did not change over time, although there were differential temporal patterns among clinical subgroups. Survival improved over time overall and according to presenting rhythm, corresponding to favorable trends in community responder, prehospital, and hospital care.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 40668576 · DOI · PMC12268528
Sedation and analgesia in post-cardiac arrest care: a post hoc analysis of the TTM2 trial [2]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundThe routine use of sedation and analgesia during post-cardiac arrest care and its association with clinical outcomes remain unclear.
- Closing excerpt
- ConclusionsIn this study, higher doses of propofol and the use of remifentanil and fentanyl were associated with good functional outcome and survival, occurrence of clinical seizures, and late awakening.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (321 words)
BackgroundThe routine use of sedation and analgesia during post-cardiac arrest care and its association with clinical outcomes remain unclear. This study aimed to describe the use of sedatives and analgesics in post-cardiac arrest care, and evaluate associations with good functional outcome, survival, clinical seizures, and late awakening.MethodsThis was a post hoc analysis of the TTM2-trial, which randomized 1900 out-of-hospital cardiac arrest patients to either normothermia or hypothermia. In both groups, deep sedation (Richmond Agitation and Sedation Scale ≤ -4) was mandatory during the 40-h intervention. Cumulative doses of sedatives and analgesic drugs were recorded within the first 72 h from randomization. Outcomes were functional outcome (modified Rankin Scale) and survival status at 6 months, occurrence of clinical seizures during the intensive care stay, and late awakening (Full outline of unresponsiveness motor score of four 96 h after randomization). Cumulative propofol doses were divided into quartiles (Q1-Q4). Logistic regression models were used to assess associations between sedative doses and functional outcome and survival, clinical seizures, and late awakening, adjusting for the severity of illness and other clinical factors influencing sedation.ResultsA total of 1861 patients were analyzed. In a multivariable logistic regression model, higher propofol doses (Q3, 100.7-153.6 mg/kg) were associated with good functional outcome (OR 1.62, 95%CI 1.12-2.34) and (Q2 and Q3, 43.9-153.6 mg/kg) with survival (OR 1.49, 95%CI 1.05-2.12 and OR 1.84, 95%CI 1.27-2.65, respectively). Receiving fentanyl and remifentanil were associated with good functional outcome (OR 1.69, 95%CI 1.27-2.26 and OR 1.50, 95%CI 1.11-2.02) and survival (OR 1.80, 95%CI 1.35-2.40 and OR 1.56, 95%CI 1.16-2.10). Receiving fentanyl (OR 0.64, 95%CI 0.48-0.86) and higher propofol doses (Q2-4 (43.9-669.4 mg/kg) were associated with the occurrence of clinical seizures. The highest quartile of propofol dose (153.7-669.4 mg/kg, OR 3.19, 95%CI 1.91-5.42) was associated with late awakening.ConclusionsIn this study, higher doses of propofol and the use of remifentanil and fentanyl were associated with good functional outcome and survival, occurrence of clinical seizures, and late awakening.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 40528173 · DOI · PMC12175406
Escalating vs Fixed Energy Defibrillation in Out-of-Hospital Cardiac Arrest Ventricular Fibrillation [3]
Abstract reading summary — source excerpts
- Opening excerpt
- ImportanceThere is limited evidence on whether higher-energy defibrillation is preferred in patients experiencing out-of-hospital cardiac arrest (OHCA) with shockable rhythms.
- Closing excerpt
- Higher-energy regimens were associated with better outcomes after all shocks, especially in patients with refractory VF.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (350 words)
ImportanceThere is limited evidence on whether higher-energy defibrillation is preferred in patients experiencing out-of-hospital cardiac arrest (OHCA) with shockable rhythms.ObjectiveTo investigate the optimal energy regimen for initial and subsequent defibrillation delivered by biphasic waveform automated external defibrillators (AEDs) in OHCA ventricular fibrillation (VF).Design, setting, and participantsThis cohort study was conducted in 48 cities across China, from 2017 to 2023, among 342 patients with OHCA who experienced at least 1 shock.ExposuresEscalating higher-energy (200-300-360 J) defibrillation or fixed low-energy (200-200-200 J) defibrillation according to the AED program available for use.Main outcome and measuresSustained and transient termination of VF and establishment of an organized rhythm after defibrillations were the main clinical outcomes.ResultsA total of 342 patients with OHCA were included (mean [SD] age, 57.2 [20.6] years; 273 male [79.8%]) with 782 VF defibrillations; 218 patients (63.8%) with a total of 480 instances (61.4%) of VF rhythm received AED with escalating higher-energy regimens. Most VF episodes were effectively terminated transiently at the first shock (200 J in both groups) (94% in the escalating higher-energy group vs 93% in the fixed lower-energy group; P = .64), but only half remained terminated until the next rhythm analysis (49% vs 47%; P = .68). Comparatively, VF that received escalating higher-energy regimens were more likely to establish sustained organized rhythm (34% vs 25%; P = .008; absolute difference, 9% [95% CI, 2% to 16%]). In refractory VF rhythms, the percentage of cases where sustained organized rhythms were established was significantly greater in escalating higher-energy regimens after second shocks and above (24% vs 13%; P = .008; absolute difference, 11% [95% CI, 3% to 19%]) and third shocks and above (35% vs 18%; P = .003; absolute difference 17% [95% CI, 5% to 27%]).Conclusions and relevanceIn this retrospective cohort study of patients experiencing OHCA-VF, both the escalating higher-energy (200-300-360 J) regimen and the fixed low-energy (200-200-200 J) regimen were effective for transient VF termination at first shock, whereas the escalating higher-energy regimens were more likely to maintain termination and restore an organized rhythm. Higher-energy regimens were associated with better outcomes after all shocks, especially in patients with refractory VF.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 40299385 · DOI · PMC12042058
Bleeding complications in patients with out-of-hospital cardiac arrest treated with cangrelor and oral P2Y12 inhibitors [4]
Abstract reading summary — source excerpts
- Opening excerpt
- AimsCangrelor is used to bridge the gap of insufficient platelet inhibition in patients with out-of-hospital cardiac arrest (OHCA) undergoing percutaneous coronary intervention (PCI).
- Closing excerpt
- ConclusionIn patients with OHCA undergoing PCI, BARC 3-5 bleeding occurred at a similar rate in patients receiving either cangrelor and transition to an oral P2Y12 inhibitor or an oral P2Y12 inhibitor alone.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (245 words)
AimsCangrelor is used to bridge the gap of insufficient platelet inhibition in patients with out-of-hospital cardiac arrest (OHCA) undergoing percutaneous coronary intervention (PCI).Methods and resultsIn a retrospective chart review study, we investigated the incidence of bleeding and stent thrombosis in patients with OHCA undergoing PCI who received either cangrelor and transition to an oral P2Y12 inhibitor or an oral P2Y12 inhibitor alone. Subgroups consisted of patients treated with conventional cardiopulmonary resuscitation (CPR) and extracorporeal CPR. The primary endpoint was Bleeding Academic Research Consortium (BARC) 3-5 bleeding at 30 days. Between January 2016 and March 2025, 414 patients were included of which 267 received cangrelor and an oral P2Y12 inhibitor and 147 received an oral P2Y12 inhibitor alone. BARC 3-5 bleeding at 30 days occurred at a similar rate in the cangrelor group and the oral P2Y12 inhibitor group (18.4% vs. 19.0%, respectively; adjusted OR, 0.79; 95% CI, 0.45-1.39). BARC 3-5 bleeding at 6, 24 and 48 h was similar between the cangrelor group and the oral P2Y12 inhibitor group in patients treated with conventional and extracorporeal CPR. In patients treated with extracorporeal CPR, stent thrombosis occurred less frequently in the cangrelor group compared with the oral P2Y12 inhibitor group (2.1% vs. 4.5%, respectively; adjusted OR, 0.32, 95% CI, 0.03-3.14), but without reaching statistical significance.ConclusionIn patients with OHCA undergoing PCI, BARC 3-5 bleeding occurred at a similar rate in patients receiving either cangrelor and transition to an oral P2Y12 inhibitor or an oral P2Y12 inhibitor alone.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 40479494 · DOI · PMC13123695
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article The global survival rate among adult out-of-hospital cardiac arrest patients who received cardiopulmonary resuscitation: a systematic review and meta-analysis [5]
- Research article Prognostic factors for extracorporeal cardiopulmonary resuscitation recipients following out-of-hospital refractory cardiac arrest. A systematic review and meta-analysis [6]
- Research article Extracorporeal cardiopulmonary resuscitation in adults: evidence and implications [7]
- Research article 2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces [8]
- Research article Incidence and outcome of out-of-hospital cardiac arrests in the COVID-19 era: A systematic review and meta-analysis [9]
- Research article 2023 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces [10]
References
- McBride O, Poel A, Counts CR, Parayil M, Osborne C, Drucker C, et al.. Temporal Patterns in Out-of-Hospital Cardiac Arrest Incidence and Outcome. . 2025. PMID 40668576 · DOI · PMC12268528
- Ceric A, Dankiewicz J, Cronberg T, Düring J, Moseby-Knappe M, Annborn M, et al.. Sedation and analgesia in post-cardiac arrest care: a post hoc analysis of the TTM2 trial. . 2025. PMID 40528173 · DOI · PMC12175406
- Tang H, Wu R, Yin L, Hao W, Shi J, Zhu H, et al.. Escalating vs Fixed Energy Defibrillation in Out-of-Hospital Cardiac Arrest Ventricular Fibrillation. . 2025. PMID 40299385 · DOI · PMC12042058
- Gelbenegger G, Lipa AJ, Jorda A, Zilberszac R, Heinz G, Staudinger T, et al.. Bleeding complications in patients with out-of-hospital cardiac arrest treated with cangrelor and oral P2Y12 inhibitors. . 2026. PMID 40479494 · DOI · PMC13123695
- Yan S, Gan Y, Jiang N, Wang R, Chen Y, Luo Z, et al.. The global survival rate among adult out-of-hospital cardiac arrest patients who received cardiopulmonary resuscitation: a systematic review and meta-analysis. Crit Care. 2020. PMID 32087741 · DOI · PMC7036236
- Debaty G, Babaz V, Durand M, Gaide-Chevronnay L, Fournel E, Blancher M, et al.. Prognostic factors for extracorporeal cardiopulmonary resuscitation recipients following out-of-hospital refractory cardiac arrest. A systematic review and meta-analysis. Resuscitation. 2017. PMID 28007504 · DOI
- Abrams D, MacLaren G, Lorusso R, Price S, Yannopoulos D, Vercaemst L, et al.. Extracorporeal cardiopulmonary resuscitation in adults: evidence and implications. Intensive Care Med. 2022. PMID 34505911 · DOI · PMC8429884
- Wyckoff MH, Greif R, Morley PT, Ng KC, Olasveengen TM, Singletary EM, et al.. 2022 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces. Circulation. 2022. PMID 36325905 · DOI
- Lim ZJ, Ponnapa Reddy M, Afroz A, Billah B, Shekar K, Subramaniam A. Incidence and outcome of out-of-hospital cardiac arrests in the COVID-19 era: A systematic review and meta-analysis. Resuscitation. 2020. PMID 33137418 · DOI · PMC7603976
- Berg KM, Bray JE, Ng KC, Liley HG, Greif R, Carlson JN, et al.. 2023 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces. Circulation. 2023. PMID 37942682 · DOI · PMC10713008
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-29.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.