CANCARE RESEARCH
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Clinical, electrographic, and imaging predictors of absent somatosensory evoked potentials in comatose survivors of cardiac arrest: A retrospective cohort study.
Clinical takeaway Clinical examination, EEG reactivity, and MRI patterns were associated with absent SSEPs in this selected cohort. These associations do not establish that the markers can replace SSEP testing or independently predict patient-centred outcomes.
Summary & abstract
Study summary
This retrospective cohort included 76 comatose adult cardiac-arrest survivors who underwent somatosensory evoked potential testing and brain MRI. Extensor or absent motor responses, absent EEG background reactivity, and combined cortical-subcortical MRI involvement were independently associated with absent cortical SSEPs, with odds ratios of 7.78, 5.98, and 8.52, respectively. The model had an AUC of 0.804, increasing to 0.866 with the addition of sex. These findings describe associations with an electrophysiological prognostic marker rather than directly measuring neurological recovery or survival.
Study limitation: The retrospective, 76-patient cohort selected patients undergoing both SSEP testing and MRI; the abstract reports no uncertainty intervals for model estimates.
Published abstract
BACKGROUND: Absence of cortical somatosensory evoked potentials (SSEPs) in comatose survivors of cardiac arrest is a proven predictor of poor neurological outcome, yet this test is not widely available or used. The correlation between absent cortical SSEPs and other clinical, electrophysiologic, and electroencephalographic (EEG) markers in this population remains incompletely defined. METHODS: We conducted a retrospective cohort study of comatose adult patients after cardiac arrest who underwent SSEPs and brain MRI, collecting clinical, neurologic, MRI, and EEG data. We classified MRI findings as cortical, subcortical, or combined. We compared variables by SSEP status using appropriate statistical tests, and logistic regression identified predictors of bilateral absence of N20 responses. We assessed model performance using the AUC. RESULTS: We included 76 comatose patients after cardiac arrest. Absence of SSEPs was associated with higher neuron-specific enolase, abnormal brainstem reflexes, upward gaze, extensor or absent motor responses, and generalized myoclonus. Combined cortical-subcortical MRI involvement and absence of EEG background reactivity were also more frequent. In multivariable analysis, extensor or absent motor response (OR 7.78), absent EEG reactivity (OR 5.98), and combined MRI involvement (OR 8.52) were independently associated with absent SSEPs. The model showed good discrimination (AUC 0.804), improving with addition of sex (AUC 0.866). CONCLUSION: Absence of EEG background reactivity, extensor or absent motor response, and combined cortical-subcortical MRI abnormalities are independently associated with absent SSEPs. These widely available markers may provide complementary prognostic information when SSEP testing is unavailable and contribute to multimodal prognostication in comatose survivors of cardiac arrest.
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Sex differences in epidemiology, care, and outcomes in patients with out-of-hospital cardiac arrest in China.
Clinical takeaway Female patients had better adjusted early resuscitation outcomes, but no clear survival or neurological advantage at later assessment. These observational findings support examining disparities across the full resuscitation pathway rather than inferring equivalent longer-term outcomes.
Summary & abstract
Study summary
This prospective multicentre Chinese cohort included 33,650 EMS-treated out-of-hospital cardiac arrests in 2020; 32.1% were female. Despite less favorable resuscitation characteristics and prehospital care, females had higher adjusted odds of prehospital return of spontaneous circulation (OR 1.21, 95% CI 1.06–1.38) and survival to hospital admission (OR 1.33, 95% CI 1.15–1.55). There was no statistically significant sex difference in survival to hospital discharge or 30 days (adjusted OR 0.85, 95% CI 0.66–1.10) or favorable neurological outcome (adjusted OR 0.84, 95% CI 0.62–1.14).
Study limitation: Observational adjustment cannot exclude residual confounding; the abstract does not report absolute survival or neurological outcome rates.
Published abstract
BACKGROUND: Data on sex differences in out-of-hospital cardiac arrest (OHCA) are well described in developed countries, but scarce in developing countries. METHODS: This prospective, multicenter, population-based observational cohort study used data from the Baseline Investigation of Out-of-hospital Cardiac Arrest (BASIC-OHCA) study collected between January 1, 2020, and December 31, 2020. Differences in outcomes were assessed using multivariable hierarchical logistic regression, with prespecified subgroup analyses and interaction tests. RESULTS: The age-standardized incidence rate of emergency medical system (EMS)-treated OHCA was higher in males than in females (48.1 vs 20.8 per 100,000 person-years, IRR = 2.31, 95% CI: 2.26-2.36) in China. Among 33,650 EMS-treated OHCA patients, 10,793 (32.1%) were females. Females had less favorable resuscitation characteristics and prehospital care than males. In multivariable models, females had significantly higher odds of prehospital return of spontaneous circulation (adjusted odds ratio [OR] = 1.21, 95% CI: 1.06-1.38) and survival to hospital admission (adjusted OR = 1.33, 95% CI: 1.15-1.55). However, no significant sex difference was observed for survival to hospital discharge or 30 days (adjusted OR = 0.85, 95% CI: 0.66-1.10), or favorable neurological outcome (adjusted OR = 0.84, 95% CI: 0.62-1.14). In subgroup analyses, females had lower odds of survival and favorable neurological outcome than males among patients aged ≥50 years, those with shockable rhythm, and those without prehospital epinephrine administration. CONCLUSIONS: In China, females demonstrated better prehospital resuscitation outcomes. However, this early advantage was lost by discharge. These findings highlight the need for integrated evaluation across prehospital and in-hospital care to inform disparity-reduction strategies.
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Rescue-breathing versus chest compression-only bystander cardiopulmonary resuscitation in non-cardiac out-of-hospital cardiac arrest: a nationwide retrospective cohort study.
Clinical takeaway The small overall associations favoring rescue-breathing CPR did not translate into clear differences in adult or elderly subgroups. These observational findings do not establish a causal benefit.
Summary & abstract
Study summary
This Japanese nationwide retrospective cohort compared rescue-breathing with compression-only bystander CPR in 154,137 patients with non-cardiac out-of-hospital cardiac arrest during 2012–2023. Rescue-breathing CPR was associated with modestly lower 30-day mortality (adjusted RR 0.98, 95% CI 0.98–0.99) and unfavorable neurological outcomes (adjusted RR 0.99, 95% CI 0.99–0.99). However, no clear differences were observed among adult or elderly patients, while pediatric patients had lower risks of both outcomes. Associations were strongest in pediatric patients and drowning-related arrests, making the overall findings less directly informative for adult cardiac critical care.
Study limitation: The cohort included pediatric patients; adult-specific effect estimates and uncertainty were not reported in the abstract, and residual confounding remains possible.
Published abstract
BACKGROUND: The role of rescue-breathing cardiopulmonary resuscitation (RB-CPR) remains controversial following guideline recommendations emphasizing chest compression-only CPR (CO-CPR). This study evaluated the associations of bystander-performed RB-CPR with mortality and unfavorable neurological outcomes in Japanese patients with non-cardiac out-of-hospital cardiac arrest (OHCA). METHODS: This retrospective nationwide cohort study included patients identified in the All-Japan Utstein Registry with non-cardiac OHCA between 2012 and 2023. Patients with a cardiac etiology or traumatic cause and those in whom resuscitation was not initiated were excluded. The analysis was restricted to patients who received bystander CPR with documented chest compressions and available information on rescue breathing. Adjusted risk ratios (RRs) were estimated using modified Poisson regression with robust variance. Prespecified subgroup and sensitivity analyses were performed. RESULTS: Among 154,137 patients, 20,124 (13.1%) received RB-CPR and 134,013 (86.9%) received CO-CPR. RB-CPR was associated with modestly lower risks of both 30-day mortality (adjusted RR 0.98, 95% CI 0.98-0.99) and 30-day unfavorable neurological outcomes (adjusted RR 0.99, 95% CI 0.99-0.99). RB-CPR was associated with lower risks of both outcomes in pediatric patients but no clear differences were observed among adult or elderly patients. Associations were strongest for pediatric patients and drowning-related arrests and modest in patients with asphyxia. CONCLUSIONS: Thirty-day mortality and unfavorable neurological outcomes were lower after RB-CPR than after CO-CPR for non-cardiac OHCA, particularly in pediatric patients. Although CO-CPR remains important in bystander CPR, rescue breathing may still have benefit, particularly in pediatric patients and those with cardiac arrest related to drowning or asphyxia.
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Emergency medical services agency-level variation in non-initiation of resuscitation and termination of resuscitation in out-of-hospital cardiac arrest.
Clinical takeaway Resuscitation initiation and termination varied substantially between EMS agencies despite adjustment. These findings support further investigation of decision-making consistency, but do not establish which agency practices are appropriate or improve outcomes.
Summary & abstract
Study summary
This retrospective cohort examined EMS-agency variation in resuscitation decisions for non-traumatic out-of-hospital cardiac arrest using 2018–2024 data. Resuscitation was not initiated in 76,859 of 560,240 encounters (13.7%). Among 309,048 encounters eligible for the Universal termination-of-resuscitation rule, 175,826 (56.9%) underwent termination. After adjustment, substantial agency-level variation remained: median odds ratios were 2.30 (95% confidence interval 2.21–2.38) for non-initiation and 4.13 (3.87–4.26) for termination, representing the median increase in odds between similar encounters treated by two randomly selected agencies.
Study limitation: Residual confounding may explain some variation; the abstract does not report survival or assess the appropriateness of individual decisions.
Published abstract
BACKGROUND: Variations in the decisions to initiate and terminate resuscitation for out-of-hospital cardiac arrest (OHCA) likely differ across emergency medical services (EMS) systems. We evaluated EMS-agency variation in non-initiation of resuscitation for EMS-assessed OHCA and applying termination of resuscitation (TOR) for those meeting the Universal TOR rule. METHODS: We conducted a retrospective cohort study of patients with non-traumatic OHCA using the 2018-2024 ESO Data Collaborative. Our outcomes were non-initiation of resuscitation and TOR. For each outcome, we quantified the extent of agency-level variation using the median odds ratio (MOR), which represents the median increase in odds when comparing similar encounters treated by two randomly selected EMS agencies, calculated from mixed-effects models that incorporated demographic, arrest, scene, agency, and EMS care variables. RESULTS: Among 560,240 encounters, resuscitation was not initiated in 76,859 (13.7%). Of the 309,048 encounters eligible for the Universal TOR rule, 175,826 (56.9%) underwent TOR. After adjustment for encounter-level factors, the median agency-specific rates were 13.6% (IQR, 11.0-16.7%) for non-initiation and 54.3% (IQR, 35.5-67.4%) for TOR. The MOR for non-initiation of resuscitation was 2.30 (95% CI 2.21-2.38), and the MOR for TOR was 4.13 (95% CI 3.87-4.26). CONCLUSION: Even after adjustment for measured patient and agency characteristics, we observed substantial between-agency variation in non-initiation of resuscitation and TOR. Findings highlight the need for further evaluation of prehospital decision-making processes and opportunities to identify and reduce unwarranted variation and improve consistency, equity, and quality of prehospital care.
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The post-ROSC ECG: morphological spectrum of non-ST-elevation occlusion and prognostic markers after cardiac arrest.
Clinical takeaway Post-ROSC ECG morphology and PR-segment duration may offer diagnostic and prognostic information. These observational findings do not establish that angiography improves survival in patients with non-ST-elevation occlusion patterns.
Summary & abstract
Study summary
This retrospective single-centre study examined first post-ROSC ECGs in 214 cardiac arrest survivors admitted to a tertiary ICU; 101 had angiographically confirmed occlusive myocardial infarction. Non-ST-elevation occlusion patterns were more prevalent than STEMI patterns overall (35% versus 24%), but angiography was less frequent (78% versus 98%; p=0.002). Patients with non-ST-elevation occlusion patterns who did not undergo angiography had the highest 30-day mortality (75%; p=0.005). After multivariable adjustment, PR-segment prolongation was associated with lower 30-day survival (adjusted odds ratio 0.977, reported interval 0.956–0.998; p=0.032).
Study limitation: Retrospective single-centre data and nonrandom angiography selection limit causal interpretation of mortality differences.
Published abstract
BACKGROUND: Occlusive myocardial infarction (OMI) frequently presents without ST-elevation (NST-OMI) after return of spontaneous circulation (ROSC), complicating triage decisions. Aim of this study was to (i) characterise the distribution of NST-OMI patterns post-ROSC and (ii) determine whether quantitative ECG features are associated with survival. METHODS: In this retrospective single-centre analysis, the first post-ROSC ECG of cardiac arrest survivors admitted to a tertiary ICU (2020-2025) was evaluated for STEMI and NST-OMI patterns and for quantitative intervals (PQ, PR, P-wave, QRS, QTc). Coronary angiography (CAG) served as the reference standard for OMI. RESULTS: Of 214 patients, 101 had CAG-confirmed OMI, wherein left-main equivalent and Smith-modified Sgarbossa criteria were the most prevalent NST-OMI patterns (each 8%), followed by Aslanger pattern (5%), lateral OMI, shark-fin sign and hyperacute t-wave (each 4%). NST-OMI patterns were more prevalent both overall (35% vs. 24%) and among CAG-confirmed OMI cases (48% vs. 44%) yet underwent CAG less frequently (78% vs. 98%; p = 0.002), with the highest 30-day mortality among NST-OMI patients not undergoing CAG (75%; p = 0.005). Regarding ECG features, non-survivors had longer PR-segment (74 vs. 57 ms; p = 0.008) and QRS-duration (130 vs. 108 ms; p = 0.003), and shorter P-wave duration (105 vs. 108 ms; p = 0.027). After multivariable adjustment, PR-segment prolongation was independently associated with reduced 30-day survival (aOR 0.977 [0.956-0.998]; p = 0.032). CONCLUSIONS: On the first post-ROSC ECG, angiographically confirmed occlusion concentrated around a small number of NST-OMI morphologies - findings of crucial importance for identification and appropriate management. PR-segment prolongation predicted reduced 30-day survival - indicating prognostic information beyond ischaemia detection.
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Out-of-hospital cardiac arrest management in the Swiss canton of Valais: a retrospective study on first responders' response and automated external defibrillator efficacy.
Clinical takeaway Public responders frequently arrived before EMS, but this study did not establish a survival advantage. The non-significant survival comparisons should not be interpreted as equivalence.
Summary & abstract
Study summary
This retrospective study included 107 consecutive out-of-hospital cardiac arrest cases in Valais, Switzerland, from January 2021 through December 2023. Public responders arrived first in 68% of cases and had a shorter emergency-call-to-arrival interval than EMS (p = 0.019). Survival on hospital arrival was 19% in the public responder group versus 24% in the EMS group; survival to discharge was 9.6% versus 15%, respectively, with neither difference statistically significant. The FRED-PA1 AED rhythm recognition algorithm was judged effective and consistent with current recommendations.
Study limitation: The small retrospective cohort limits causal inference and precision of survival comparisons; the abstract provides no confidence intervals or adjusted estimates.
Published abstract
STUDY AIMS: Cardiac arrest is a condition with a high mortality rate, with most cases occurring outside hospital. First responders (defined as public responders in our study) play an increasingly important role in management through the early initiation of cardiopulmonary resuscitation and defibrillation. Several studies have shown that the involvement of public responders can result in faster initiation of resuscitation and increased survival. This study evaluated the management of out-of-hospital cardiac arrest by public responders and the effectiveness of the FRED-PA1 automated external defibrillator (AED) available in the canton of Valais, Switzerland. METHODS: This was a retrospective study including consecutive cases of out-of-hospital cardiac arrest occurring between January 2021 and December 2023 in the canton of Valais. Response times of public responders and emergency medical services (EMS) were evaluated, along with initial rhythms, survival, and the performance and safety of the available AEDs. RESULTS: A total of 107 patients were included in the study. In 68% of cases, a public responder arrived at the scene first, with a significantly shorter interval between emergency call and on-site arrival compared with EMSs (p = 0.019). Ventricular fibrillation was more frequent in the EMS group than the public responders group (35 vs 23%) (non-significant [NS]). Survival on arrival at hospital was 19% in the public responder group and 24% in the EMS group (NS). Survival to hospital discharge was 9.6% in the public responder group and 15% in the EMS group (NS). Concerning the AEDs, the rhythm recognition algorithm was deemed to be effective and consistent with current recommendations. CONCLUSION: This retrospective study demonstrates the key role played by public responders, who are frequently the first to arrive at the scene of out-of-hospital cardiac arrests. The FRED-PA1 AED algorithm meets the standards in the literature. However, ongoing prospective studies will highlight and optimise the role of public responders in out-of-hospital cardiac arrests.
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Intra-arrest strategies to treat cardiac arrest due to a non-opioid toxicological causes in adults and children: a systematic review.
Clinical takeaway Evidence for toxicology-specific modifications during cardiac arrest remains highly uncertain. The sodium bicarbonate finding is observational and does not establish that bicarbonate caused lower survival.
Summary & abstract
Study summary
This systematic review assessed modifications to advanced life support during presumed toxicological cardiac arrest, excluding studies focused specifically on opioid toxicity. Four observational studies examined nine interventions; none specifically focused on children, and three enrolled fewer than 100 patients. The primary outcome was 30-day survival. In the largest study (1,545 patients), sodium bicarbonate use during out-of-hospital arrest following suspected drug overdose was associated with lower survival to hospital discharge (adjusted odds ratio 0.16, 95% confidence interval 0.08–0.31). All studies had critical risk of bias, and intervention effect estimates were generally very imprecise.
Study limitation: Only four observational studies were available, all at critical risk of bias; none specifically focused on children.
Published abstract
OBJECTIVE: To summarise evidence on the effectiveness of specific alterations to standard advanced life support during ongoing cardiopulmonary resuscitation in adults and children with cardiac arrest due to a presumed toxicological cause. METHODS: We searched MEDLINE (OVID platform), Embase (OVID platform), and Cochrane CENTRAL from inception to 22nd July 2026 for relevant observational and interventional studies with a control group. We excluded studies focussed specifically on opioid toxicity. Two authors independently screened studies for inclusion. Our primary outcome was 30-day survival. We assessed risk of bias using the Cochrane recommended tools and certainty of evidence using the GRADE system. RESULTS: We identified four observational studies, of which none specifically focused on children and three included fewer than 100 patients. Studies examined general toxicological causes (n = 2), smoke inhalation and cyanide poisoning (n = 1), and beta-blocker and calcium-channel blocker overdose (n = 1). All studies were at critical risk of bias.Across the four studies, nine interventions were reported. Whilst some interventions were associated with either benefit or harm, estimates of effect were very imprecise and challenging to interpret. The largest study (1545 patients) reported that sodium bicarbonate use in out-of-hospital cardiac arrest due to suspected drug overdose was associated with lower survival to hospital discharge (adjusted odds ratio 0.16, 95% confidence interval 0.08-0.31). CONCLUSION: Current evidence does not support the modification of standard advanced life support during cardiac arrest due to a presumed toxicological cause in adults or children.Registration: PROSPERO CRD420251149412.
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Signs of Life and Clinical Outcomes in Patients With Traumatic Out-of-Hospital Cardiac Arrest: A Nationwide Multicenter Observational Study.
Clinical takeaway Scene cardiac electrical activity, particularly with spontaneous respiration, was associated descriptively with greater survival beyond the emergency department. These findings do not establish long-term prognosis or a basis for resuscitation decisions.
Summary & abstract
Study summary
A retrospective analysis of a multicenter prospective registry included 462 adults with traumatic out-of-hospital cardiac arrest, excluding patients with a palpable pulse at EMS arrival. Patients were grouped by pupillary light reflex, spontaneous respiration, and cardiac electrical activity at the scene. Overall, 22 patients (4.8%) survived beyond the emergency department, while 318 (68.8%) had no signs of life at the scene. Survival beyond the emergency department was highest with cardiac activity plus spontaneous respiration (4/16; 25%), followed by cardiac activity alone (10/117; 8.5%).
Study limitation: Small descriptive subgroups and an endpoint limited to survival beyond the emergency department constrain prognostic interpretation.
Published abstract
BACKGROUND: The prognostic value of individual signs of life (SOLs) remains unclear in patients experiencing traumatic out-of-hospital cardiac arrest (t-OHCA). OBJECTIVES: To describe clinical outcomes among patients with t-OHCA by the presence of each SOL at the scene. METHODS: Data from the SOS-KANTO 2017 study, a multicenter prospective registry of OHCA cases treated between 2019 and 2021, were retrospectively analyzed. Adult patients diagnosed with t-OHCA were included, excluding those with a palpable pulse upon emergency medical service (EMS) arrival. Patients were categorized into eight subgroups based on the presence of three SOLs at the scene-the pupillary light reflex, spontaneous respiration, and cardiac electrical activity - and descriptive analyses were performed. The primary outcome was survival beyond the emergency department (ED). RESULTS: Of the 462 patients included in the analysis, two (0.4%) exhibited all three SOLs, and 18 (3.9%) exhibited two SOLs; in the latter group, two demonstrated cardiac activity and a pupillary reflex, and 16 had cardiac activity and spontaneous respiration. Among the 124 patients (26.8%) with only one SOL, 117 had cardiac activity, three showed a pupillary reflex, and four exhibited spontaneous respiration. No SOLs were observed in 318 patients (68.8%). Overall, 22 patients (4.8%) survived beyond the ED. The highest survival rate was observed in the subgroup with both cardiac activity and spontaneous respiration (4/16; 25%), followed by the subgroup with cardiac activity alone (10/117; 8.5%). CONCLUSIONS: Among the t-OHCA patients, survival beyond the ED was observed more frequently in those with cardiac electrical activity at the scene.
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The Incidence of Bone Cement Implantation Syndrome Grade 3 in Hip and Knee Arthroplasty: A Retrospective Multicenter Case Series.
Clinical takeaway This series identifies a rare perioperative arrest syndrome with high mortality, concentrated in elderly patients undergoing hip-fracture hemiarthroplasty. It does not establish preventive or resuscitation strategies.
Summary & abstract
Study summary
This retrospective study examined grade 3 bone cement implantation syndrome across hip and knee arthroplasty procedures at four Dutch hospitals. Cases required cardiovascular collapse needing CPR between joint manipulation and skin closure. There were no cases among 25,914 knee arthroplasties, versus 31 among 39,237 hip procedures (0.08%). Of these 31 cases, 27 occurred during hemiarthroplasty for femoral neck fracture. Affected patients had a mean age of 86.2 years, 87.1% underwent cemented procedures, and perioperative mortality was 67.7%, highlighting the severe outcomes accompanying this uncommon perioperative arrest syndrome.
Study limitation: Retrospective case ascertainment and only 31 events limit precision; the abstract does not define the perioperative mortality time window.
Published abstract
BACKGROUND: Cardiac arrest during hip or knee arthroplasty (KA) represents the most severe manifestation of bone cement implantation syndrome (BCIS). However, true incidence rates remain uncertain, and data on clinical characteristics and outcomes are limited. The aim of this study was to determine the incidence of BCIS grade 3 in hip and KA and to describe associated clinical characteristics and mortality. METHODS: This retrospective multicenter case series included all hip and KA procedures performed at 4 Dutch hospitals. Potential cases were identified through database queries. Medical records were manually reviewed to confirm BCIS grade 3, defined as cardiovascular collapse requiring cardiopulmonary resuscitation occurring from joint manipulation through skin closure. RESULTS: No cases of BCIS grade 3 occurred during 25,914 knee arthroplasties. Among 39,237 hip procedures, 31 patients experienced BCIS grade 3 (0.08%), of which 27 cases occurred during hemiarthroplasty for femoral neck fracture (FNF). The mean age of patients with BCIS grade 3 was 86.2 ± 7.7 years; 71.0% were female, 93.5% underwent acute surgery for FNF, 87.1% involved cemented procedures, and perioperative mortality was 67.7%. CONCLUSION: BCIS grade 3 is rare but highly lethal, occurring predominantly during hemiarthroplasty for FNF in elderly patients. Individualized risk assessment and informed consent are essential when managing FNF in high-risk patients. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
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Incidence of refibrillation and shock-resistant ventricular fibrillation during OHCA when treated with a public access defibrillator: implications for CPR timing in lay rescuer-treated OHCA.
Clinical takeaway Refibrillation was more common than three-shock-resistant ventricular fibrillation in this lay-rescuer-treated cohort. The findings support further investigation of CPR-cycle timing, but do not establish an optimal interval or demonstrate a survival benefit.
Summary & abstract
Study summary
This retrospective study analysed ECG recordings from out-of-hospital cardiac arrests treated by lay rescuers using public access defibrillators. Among 1459 patients receiving at least one shock, 498 (34.1%) experienced refibrillation. The median number of refibrillations per patient was 1 (IQR 1–2), and median time to refibrillation was 29.8 seconds. Three consecutive shocks were observed in 231 patients (15.8%); only 11 of these patients (4.8%) had shock-resistant ventricular fibrillation, defined as three consecutive failed shocks. These findings distinguish recurrent fibrillation from persistent failure of defibrillation in this setting.
Study limitation: Retrospective ECG analysis describes rhythm outcomes; the abstract reports neither survival outcomes nor a direct comparison of CPR-cycle durations.
Published abstract
BACKGROUND: Out-of-hospital cardiac arrest (OHCA) treatment often requires multiple defibrillatory shocks due to failed defibrillation or refibrillation. The complete nature of refractory ventricular fibrillation (VF) is unknown, as many studies do not consider shocks delivered by lay rescuers prior to the arrival of basic life support (BLS)/advanced life support (ALS) when quantifying refractory VF. ERC guidelines define refractory VF as continuous VF after three consecutive shocks, not differentiating between patients who refibrillate and those with shock-resistant VF (three consecutive failed shocks) which may contribute to this variation in reported incidence. There are some differences in treatment recommendations for patients who refibrillate and those with shock-resistant VF. Therefore, understanding the number of shocks delivered by lay-rescuers with public access defibrillators (PADs) and the patient's response to them prior to BLS/ALS arrival may inform treatment strategies. METHODS: ECG data collected retrospectively from OHCAs treated by lay-rescuers using PADs were analysed. Cardiac rhythm, shock success, refibrillation, time to refibrillation and presence of shock-resistant VF (three consecutive failed shocks) were determined by two investigators. RESULTS: Data were available for 1459 patients receiving at least one shock. Refibrillation occurred in 498 (34.1%) patients. The median number of refibrillations per patient was 1 (IQR 1, 2). Median time to refibrillation was 29.8 s. Three consecutive shocks were observed in 231 of the 1459 (15.8%) patients, 11 patients (4.8% of 231 patients) had shock-resistant VF. CONCLUSION: When treated by lay-rescuers with PADs, refibrillation occurrence is lower than that reported for patients treated by BLS/ALS. However, aligned with BLS/ALS studies, in lay-rescuer treated OHCA, refibrillation typically occurs within the first 30 s following a successful shock. Therefore, patients who refibrillate are typically in VF for an additional 1.5 min before receiving a subsequent shock for PADs with a 2 min cardiopulmonary resuscitation (CPR) cycle. This finding emphasises the need for investigation into optimal CPR duration for patients requiring multiple shocks.
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Clinical and Financial Value of Cardiac Point-of-Care Ultrasound During Traumatic Cardiac Arrest.
Clinical takeaway Cardiac activity on POCUS was associated with admission survival, but evidence for discharge survival was inconclusive. These findings do not establish ultrasound findings as a stand-alone basis for resuscitation decisions.
Summary & abstract
Study summary
This single-center retrospective study included 74 patients with presumed traumatic cardiac arrest who underwent cardiac POCUS during initial resuscitation. Two of 17 patients with cardiac activity survived to discharge; both ultimately had medical rather than traumatic etiologies. None of 57 patients without cardiac activity survived to discharge (95% CI, 0–6.3%). Cardiac activity was associated with greater survival to admission (OR, 49.8; 95% CI, 5.5–446.9), but the discharge association was not statistically significant (OR, 18.6; 95% CI, 0.84–406.7); resuscitation duration and hospital charges were also higher.
Study limitation: The small, single-center retrospective cohort included only patients receiving POCUS, and both discharge survivors ultimately had nontraumatic etiologies.
Published abstract
INTRODUCTION: Traumatic cardiac arrest is associated with poor survival and significant consumption of hospital resources. Determining which patients have survivable injuries allows for judicious use of resources. Our aim was to determine whether cardiac activity on point-of-care ultrasound (POCUS) during traumatic cardiac arrest was associated with increased patient survival and the charges of continued resuscitation in patients that do have cardiac activity on POCUS. METHODS: We conducted this single-center retrospective study at an urban, Level I trauma center of consecutive patients arriving in traumatic cardiac arrest from August 2016-December 2023 who had a cardiac POCUS performed during the initial resuscitation efforts. Our primary outcome was to determine whether cardiac activity on POCUS during the arrest was associated with increased patient survival to neurologically intact hospital discharge. Secondary objectives included determining whether there was a correlation between cardiac activity on POCUS during traumatic cardiac arrest and survival to hospital admission. Additionally, we evaluated hospital charges and length of stay associated with continued resuscitation in patients who demonstrated cardiac activity on ultrasound. RESULTS: We identified 134 patients in traumatic cardiac arrest, of whom 74 (55.2%) had a cardiac POCUS performed and met inclusion criteria. A total of 17 patients had cardiac activity noted on the initial POCUS, with two (11%) surviving to hospital discharge (95% CI, 1.3-39.7). The two survivors initially categorized as being in traumatic cardiac arrest were ultimately found to have medical etiologies and not trauma. Of the 57 patients who had no cardiac activity noted on POCUS, none survived to hospital discharge (95% CI, 0-6.3%). More patients survived to hospital admission who had cardiac activity on their initial POCUS compared with those who had no cardiac activity (odds ratio [OR], 49.8; 95% CI, 5.5-446.9; P < .001). More patients survived to hospital discharge as well, but this was not statistically significant (OR, 18.6; 95% CI, 0.84-406.7, P = .06). Traumatic cardiac arrest patients who had present cardiac activity had longer code times prior to terminating efforts (26.6 vs 7.7 minutes, P < .001) and had higher overall charges per patient ($91,321 vs $10,032), P < .001). CONCLUSION: The absence of cardiac activity on POCUS in patients with traumatic cardiac activity is likely to be fatal. The presence of cardiac activity was associated with increased resuscitation times, charges, and survival to hospital admission but not necessarily to hospital discharge.
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