Dion A. Stub

Description:Despite advancements in resuscitation care, survival rates following out-of-hospital cardiac arrest (OHCA) remain low.1,2 In patients presenting with ventricular fibrillation (VF), between 40% and 50% prove refractory to standard defibrillation, with these patients having particular poor outcomes.3 The landmark Double Sequential External Defibrillation for Refractory Ventricular Fibrillation (DOSE VF) trial demonstrated that alternative defibrillation strategies – double sequential external defibrillation (DSED) and vector-change (VC) defibrillation – significantly improved survival to hospital discharge compared to standard defibrillation.2 DSED showed particularly robust benefits including a higher likelihood of neurologically intact survival.2

Description:Alpine tourism annually attracts over 100 million visitors globally. Age and cardiovascular comorbidities in alpine tourists are increasing, and rates of out-of-hospital cardiac arrest (OHCA) have been hypothesized to be higher due to exertion and physiological stress. Cases of alpine OHCA from 2002 to 2021 were identified from the statewide Victorian Ambulance Cardiac Arrest Registry. Alpine and nonalpine OHCA characteristics were compared. Causes of alpine OHCA were obtained from hospital discharge diagnoses and the National Coronial Information System. Approximately 15.3 million alpine visits were recorded over the time period, during which 13 alpine OHCAs occurred (0.04% of 32,179 OHCAs, 0.8 OHCAs per million alpine visits). Compared with nonalpine OHCAs in a public setting, alpine OHCA patients were younger (median age 52 years vs 63 years, P = .0373), with higher rates of bystander defibrillation (54.5% vs 13.5%, P < .0001). Survival to hospital discharge did not significantly differ between alpine (38.5%) and nonalpine OHCA patients. Ischemic heart disease was the commonest identified cause of alpine OHCA in both survivors and nonsurvivors. Alpine OHCA is very rare in Australia, accounting for 1 in 5000 OHCAs and fewer than 1 in a million ski field visitors. Despite remoteness and access challenges, alpine OHCA survival is high, driven by prognostically favorable arrest-related factors and coordinated local systems of care prioritizing early bystander intervention.

Description:The diagnostic accuracies of different electrocardiography (ECG) interpretation methods remain unclear. Therefore, this study aimed to systematically evaluate and compare the diagnostic accuracy of prehospital 12-lead ECG interpretation methods for identifying ST-elevation myocardial infarction (STEMI) and activating cardiac catheterization laboratories (CCLs). A comprehensive search was conducted in Medline, Scopus, and CINAHL databases up to August 2024. Two reviewers independently selected studies that assessed the diagnostic accuracy of prehospital 12-lead ECG in real-time STEMI identification and CCL activation. Pooled estimates of sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) were calculated using bivariate generalized mixed-effects regression models or random-effects meta-analysis as appropriate. The quality of the included studies was assessed using the QUADAS-2 tool. Thirty-six studies involving 67,168 patients were included. Overall, for STEMI identification, the pooled AUC of ECG was 0.96 (95%CI:0.94-0.98), sensitivity was 80% (95% CI, 69-88%), specificity was 97% (95%CI: 94-98%), and DOR was 114 (95%CI: 59-222). Ambulance clinicians achieved the highest DOR (264; 95%CI: 33-2125), followed by transmission method (136; 95%CI, 59-312) and computer-assisted analysis (78; 95%CI: 33-186). Transmission method demonstrated superior specificity (‎0.98; 95%CI: 0.94-0.99‎) and the lowest rates of inappropriate (13.2%; 95% CI: ‎8.6%-19.2%), and false-positive (11.0%; 95%CI: 6.9%-15.0%) CCL activations. All prehospital ECG interpretation methods yielded acceptable diagnostic accuracy for STEMI identification; however, transmission offered the greatest specificity and fewer unnecessary CCL activations. Adopting transmission-based strategies, where feasible, and enhancing training and decision support for ambulance clinicians may improve prehospital STEMI detection and resource utilization.

Description:Long-term outcomes and quality of life have been identified as core patient-centered outcomes for venoarterial extracorporeal membrane oxygenation (VA-ECMO) research. The aim of this study is to investigate the incidence of death or new disability at 12 months after the initiation of VA-ECMO. Prospective, multicenter, registry-embedded cohort study in 26 hospitals in Australia and New Zealand from February 2019 through April 2023. Adult patients admitted to a participating ICU and who underwent VA-ECMO were included. The primary outcome was death or new disability at 6 and 12 months. All results were adjusted for patient characteristics at the time of ECMO initiation. Among 389 patients who received VA-ECMO (median age, 57 [44-65] years; 35% women), the incidence of death or new disability at 12 months was 70.6% compared with 70.8% at 6 months (adjusted odds ratio for 12 versus 6 months, 0.61 [95% CI, 0.25-1.49]; P=0.27). Compared with 6 months, at 12 months after VA-ECMO more patients were independent in activities of daily living (62.1% versus 48.2%; adjusted odds ratio, 2.84 [95% CI, 1.50-5.36]; P=0.001), and fewer patients were unemployed due to health reasons (32.7% versus 47.4%; adjusted odds ratio, 0.29 [95% CI, 0.13-0.65]; P<0.001). Differences in outcomes were found according to the reason for VA-ECMO initiation. At 12 months after VA-ECMO, 30% of patients are alive and without disability, with differences in outcome associated with the reason for VA-ECMO initiation. The major burden of disability appears to develop in the first 6 months after VA-ECMO initiation and is sustained between 6 and 12 months. URL: https://www.clinicaltrials.gov; Unique identifier: NCT03793257.

Description:Objective: The aim of this study was to quantify the yield of continuous cardiac monitoring (CCM) in patients with pre-specified low-risk criteria, including those with mildly elevated troponin levels. Methods: This was a retrospective cohort study of patients admitted to the ward from the emergency department (ED) with CCM. The primary outcome was the occurrence of clinically relevant arrhythmia. The secondary outcome was immediately life-threatening arrhythmia. Sub-group analyses were performed for patients presenting with chest pain, with initial mildly elevated and negative troponin levels. Results: Of 1639 patients who were admitted to the ward from the ED with CCM, 403 met pre-specified low-risk criteria. Of those 403 patients, there were 16 (3.96%; 95% CI: 1.52%-6.38%) patients who had clinically relevant arrhythmia, and none had a critical arrhythmia. Among the subgroup of 84 patients presenting with chest pain who had a mildly elevated initial troponin, there was one clinically relevant arrhythmia (1.19%; 95% CI 0.00%-3.53%), and among the 174 patients presenting with chest pain and a negative troponin, there were five who had clinically relevant arrhythmia (2.94%; 95% CI: 0.44%-5.44%). Conclusions: CCM in pre-specified low-risk patients admitted to the ward from the ED did not capture any immediately life-threatening arrhythmia. The observation of clinically relevant arrhythmia suggests that some relatively lower risk patients may benefit from CCM. Elucidation of this cohort can reduce the number of referrals for CCM and potentially improve patient flow within a hospital.