Identifying Subgroups with Differential Responses to Amiodarone among Cardiac Arrest Patients with a Shockable Rhythm at Hospital Arrival using the Machine Learning Approach.

Background: There are few reports of studies on the differential effects of amiodarone among out-of-hospital cardiac arrest (OHCA) patients with a shockable rhythm at hospital arrival. The present study aimed to investigate the clinical heterogeneity of OHCA patients with a shockable rhythm upon hospital arrival and to identify subgroups with differential responses to amiodarone, using a machine learning approach. Methods: We used the Japanese nationwide OHCA registry of the Japanese Association for Acute Medicine for this study; data from OHCA patients with a shockable rhythm at hospital arrival were included in the analyses. The primary outcome was a favorable neurological outcome at 30 days. We developed a scoring system by the weighting method with logistic likelihood loss to identify patient subgroups showing differential effects of amiodarone from the point of view of the neurological outcome and survival at 30 days. Results: Among the 68,111 cases of OHCA in the registry, the data of 2333 OHCA patients with an initial shockable rhythm at hospital arrival were analyzed. The developed score identified higher age, longer interval between the call to the emergency medical service and hospital arrival, absence of a "witness", no defibrillation prior to hospital arrival, hypothermia at hospital arrival, and pre-hospital epinephrine administration as variables that were significantly associated with a beneficial effect of amiodarone. Based on the results of the developed scoring system, 47% (1107/2333) of the patients were considered to greatly benefit from amiodarone administration, whereas 53% (1226/2333) of patients were considered to not benefit from amiodarone administration. The effect of amiodarone on the neurological outcome at 30 days varied significantly among the subgroups identified by the developed score ( OR interaction : 1.07 [95% confidence interval (CI): 0.99-1.13], p = 0.005). Conclusions: We successfully developed a model that could discriminate between OHCA patients with an initial shockable rhythm at hospital arrival who would benefit or not benefit from the administration of amiodarone in terms of the neurological outcome at 30 days. There was clinical heterogeneity among OHCA patients with a shockable rhythm in terms of their response to amiodarone.

Analysis of cardiac arrest after coronary artery bypass grafting.

BACKGROUND: Cardiac arrest after coronary artery bypass grafting (CABG) is a serious complication with low survival rate. The prognosis of patients with cardiac arrest in the general ward is worse than that in the intensive care unit (ICU) because of the delayed and poor rescue conditions. METHODS: This retrospective study included patients who experienced cardiac arrest after CABG surgery between January 2010 and December 2019 at the Fuwai Hospital. Differences in cardiac arrest between the ICU and the general ward were compared. The patients were divided into shockable and non-shockable rhythm groups, and the differences between the two groups were compared. Finally, we proposed a management protocol for cardiac arrest in the general ward. RESULTS: We retrospectively analyzed 41,450 patients who underwent CABG only, of whom 231 (0.56%) experienced cardiac arrest post-surgery in the ICU (185/231) or in the general ward (46/231). The rescue success rate and 30-day survival rate of the patients with cardiac arrest in the general ward were 76.1% (35/46) and 58.7% (27/46), respectively. The incidence of the different arrhythmia types of cardiac arrest in the general ward compared with that in the ICU was different (P = 0.010). The 30-day survival rate of the non-shockable rhythm group was 31.8% (7/22), which was worse than that of the shockable rhythm group (83.3% [20/24]; P = 0.001). Kaplan-Meier survival analysis showed that the prognosis of the non-shockable group was poor (P < 0.001). CONCLUSIONS: The incidence of cardiac arrest after CABG was low. The prognosis of patients in the general ward was worse than that of those in the ICU. The proportion of non-shockable rhythm type cardiac arrest was higher in the general ward than in the ICU, and patients in this group had a worse early prognosis.

Management of Paediatric Cardiac Arrest due to Shockable Rhythm-A Simulation-Based Study at Children's Hospitals in a German Federal State.

(1) Background: To improve the quality of emergency care for children, the Hessian Ministry for Social Affairs and Integration offered paediatric simulation-based training (SBT) for all children's hospitals in Hesse. We investigated the quality of paediatric life support (PLS) in simulated paediatric resuscitations before and after SBT. (2) Methods: In 2017, a standardised, high-fidelity, two-day in-house SBT was conducted in 11 children's hospitals. Before and after SBT, interprofessional teams participated in two study scenarios (PRE and POST) that followed the same clinical course of apnoea and cardiac arrest with a shockable rhythm. The quality of PLS was assessed using a performance evaluation checklist. (3) Results: 179 nurses and physicians participated, forming 47 PRE and 46 POST interprofessional teams. Ventilation was always initiated. Before SBT, chest compressions (CC) were initiated by 87%, and defibrillation by 60% of teams. After SBT, all teams initiated CC (p = 0.012), and 80% defibrillated the patient (p = 0.028). The time to initiate CC decreased significantly (PRE 123 ± 11 s, POST 76 ± 85 s, p = 0.030). (4) Conclusions: The quality of PLS in simulated paediatric cardiac arrests with shockable rhythm was poor in Hessian children's hospitals and improved significantly after SBT. To improve children's outcomes, SBT should be mandatory for paediatric staff and concentrate on the management of shockable rhythms.

The impact of time to defibrillation on return of spontaneous circulation in out-of-hospital cardiac arrest patients with recurrent shockable rhythms.

OBJECTIVE: Optimal timing for subsequent defibrillation attempts for Out-of-hospital cardiac arrest (OHCA) patients with recurrent VF/pVT is uncertain. We investigated the relationship between VF/pVT duration and return of spontaneous circulation (ROSC) in OHCA patients with recurrent shockable rhythms. METHODS: We analyzed data from the Salt Lake City Fire Department (SLCFD) spanning from 2012 to 2023. The implementation of rhythm-filtering technology since 2011 enabled real-time rhythm interpretation during CPR, with local protocols allowing early defibrillation for recurrent/refractory VF/pVT cases. We included patients experiencing four or five episodes of VF and pVT rhythms and employed generalized estimating equation (GEE) regression analysis to examine the association between VF/pVT durations preceding recurrent defibrillation and return of spontaneous circulation (ROSC). RESULTS: Analysis of 622 appropriate shocks showed that patients achieving ROSC had significantly shorter median VF/pVT duration than those who did not achieve ROSC (0.83 minutes vs. 1.2 minutes, p = 0.004). Adjusted analysis of those with 4 VF/pVT episodes (N = 142) revealed that longer VF/pVT durations were associated with lower odds of achieving ROSC (odds ratio: 0.81, 95% CI: 0.72-0.93, p = 0.005). Every one-minute delay in intra-arrest defibrillation is predicted to decrease the likelihood of achieving ROSC by 19%. CONCLUSION: Every one-minute increase in intra-arrest VF/pVT duration was associated with a statistically significant 19% decrease in the chance of achieving ROSC. This highlights the importance of reducing time to shock in managing recurrent VF/pVT. The findings suggest reevaluating the current recommendations of two minutes intervals for rhythm check and shock delivery.

Predictors and rate of survival after Out-of-Hospital Cardiac Arrest.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a major public health concern and encloses a wide spectrum of causes. The purpose of this study is to assess predictors and rate of survival at hospital discharge and long-term in the setting of OHCA. The secondary endpoint is to compare OHCA-survival outcomes of presumed ischemic versus non ischemic cause. METHODS: A retrospective cohort was conducted on 318 consecutive patients admitted for OHCA at Civilian Hospitals of Colmar between 2010 and 2019. Data concerning baseline characteristics, EKG, biological parameters, and coronary angiograms were collected. We observed the living status (alive or dead) of each of study's participants by March 2023. RESULTS: The observed survival rate was 34.3 % at hospital discharge and 26.7 % at 7.1-year follow up. The mean age of study population was 63 ± 16 years and 32.7 % were women. 65.7 % of OHCA-patients underwent coronary angiography that revealed a significant coronary artery disease (CAD) in half of study participants. Primary angioplasty was performed in 43.4 % of study population. The in-hospital mortality rate was significantly higher in those with RBBB (83.7 % vs. 62.5 %, p = 0.004), diabetes mellitus (84.2 % vs. 59.9 %, p < 0.001), arterial hypertension (72.2 % vs. 57.7 %, p = 0.007), peripheral arterial disease (79.2 % vs. 52.2 %, p = 0.031) whereas it was lower in case of anterior STEMI (43.9 % vs 71.4 %, p < 0.001), presence of obstructive CAD (52.2 % vs. 79.2 %, p < 0.001), primary angioplasty performance (48.6 % vs. 78.9 %, p < 0.001), initial shockable rhythm (43.8 % vs. 88.6 %, p < 0.001), initial chest pain (49.4 % vs. 71.5 %, p < 0.001). After adjusting on covariates, the Cox model only identified an initial shockable rhythm as independent predictor of survival at hospital discharge [HR = 0.185, 95 %CI (0.085-0.404), p < 0.001] and 7-year follow up [HR = 0.201, 95 %CI (0.082-0.492), p < 0.001]. The Kaplan-Meier and log Rank test showed a difference in survival outcomes between OHCA with versus without CAD (p < 0.001). CONCLUSION: The proportion of OHCA-survivors is small despite the development of emergency health care system. Initial shockable rhythm is the strong predictor of survival. OHCA of presumed coronary cause is associated with a better long-term survival outcome.

Association between defibrillation-to-adrenaline interval and short-term outcomes in patients with out-of-hospital cardiac arrest and an initial shockable rhythm.

Aim: The optimal timing of adrenaline administration after defibrillation in patients with out-of-hospital cardiac arrest (OHCA) and an initial shockable rhythm is unknown. We investigated the association between the defibrillation-to-adrenaline interval and clinical outcomes. Methods: Between 2011 and 2020, we enrolled 1,259,960 patients with OHCA into a nationwide prospective population-based registry in Japan. After applying exclusion criteria, 20,905 patients with an initial shockable rhythm documented at emergency medical services (EMS) arrival who received adrenaline after defibrillation were eligible for this study. Multivariable logistic regression analysis was used to predict favourable short-term outcomes: prehospital return of spontaneous circulation (ROSC), 30-day survival, or a favourable neurological outcome (Cerebral Performance Category 1 or 2) at 30 days. Patients were categorised into 2-minute defibrillation-to-adrenaline intervals up to 18 min, or more than 18 min. Results: At 30 days, 1,618 patients (8%) had a favourable neurological outcome. The defibrillation-to-adrenaline interval in these patients was significantly shorter than in patients with an unfavourable neurological outcome [8 (5-12) vs 11 (7-16) minutes; P < 0.001]. The proportion of patients with prehospital ROSC, 30-day survival, or a favourable neurological outcome at 30 days decreased as the defibrillation-to-adrenaline interval increased (P < 0.001 for trend). Multivariable analysis revealed that a defibrillation-to-adrenaline interval of > 6 min was an independent predictor of worse prehospital ROSC, 30-day survival, or neurological outcome at 30 days when compared with an interval of 4-6 min. Conclusion: A longer defibrillation-to-adrenaline interval was significantly associated with worse short-term outcomes in patients with OHCA and an initial shockable rhythm.

The link between initial cardiac rhythm and survival outcomes in in-hospital cardiac arrest using propensity score matching, adjustment, and weighting.

The association between the initial cardiac rhythm and short-term survival in patients with in-hospital cardiac arrest (IHCA) has not been extensively studied despite the fact that it is thought to be a prognostic factor in patients with out-of-hospital cardiac arrest. This study aimed to look at the relationship between initial shockable rhythm and survival to hospital discharge in individuals with IHCA. 1516 adults with IHCA who received chest compressions lasting at least two minutes at the National Taiwan University Hospital between 2006 and 2014 made up the study population. Propensity scores were estimated using a fitted multivariate logistic regression model. Various statistical methodologies were employed to investigate the association between shockable rhythm and the probability of survival to discharge in patients experiencing IHCA, including multivariate adjustment, propensity score adjustment, propensity score matching, and logistic regression based on propensity score weighting. In the original cohort, the multivariate-adjusted odds ratio (OR) was 2.312 (95% confidence interval [CI]: 1.515-3.531, P < 0.001). In additional propensity score adjustment, the OR between shockable rhythm and the probability of survival to hospital discharge in IHCA patients was 2.282 (95% CI: 1.486, 3.504, P < 0.001). The multivariate-adjusted logistic regression model analysis revealed that patients with shockable rhythm had a 1.761-fold higher likelihood of surviving to hospital release in the propensity score-matched cohort (OR = 2.761, 95% CI: 1.084-7.028, P = 0.033). The multivariate-adjusted OR of the inverse probability for the treatment-weighted cohort was 1.901 (95% CI: 1.507-2.397, P < 0.001), and the standardized mortality ratio-weighted cohort was 2.692 (95% CI: 1.511-4.795, P < 0.001). In patients with in-hospital cardiac arrest, Initial cardiac rhythm is an independent predictor of survival to hospital discharge. Depending on various statistical methods, patients with IHCA who have a shockable rhythm have a one to two fold higher probability of survival to discharge than those who have a non-shockable rhythm. This provides a reference for optimizing resuscitation decisions for IHCA patients and facilitating clinical communication.

The Current Discussion Regarding End-of-Life Care for Patients with Out-of-Hospital Cardiac Arrest with Initial Non-Shockable Rhythm: A Narrative Review.

Despite recent advances in resuscitation science, outcomes in patients with out-of-hospital cardiac arrest (OHCA) with initial non-shockable rhythm remains poor. Those with initial non-shockable rhythm have some epidemiological features, including the proportion of patients with a witnessed arrest, bystander cardiopulmonary resuscitation (CPR), age, and presumed etiology of cardiac arrest have been reported, which differ from those with initial shockable rhythm. The discussion regarding better end-of-life care for patients with OHCA is a major concern among citizens. As one of the efforts to avoid unwanted resuscitation, advance directive is recognized as a key intervention, safeguarding patient autonomy. However, several difficulties remain in enhancing the effective use of advance directives for patients with OHCA, including local regulation of their use, insufficient utilization of advance directives by emergency medical services at the scene, and a lack of established tools for discussing futility of resuscitation in advance care planning. In addition, prehospital termination of resuscitation is a common practice in many emergency medical service systems to assist clinicians in deciding whether to discontinue resuscitation. However, there are also several unresolved problems, including the feasibility of implementing the rules for several regions and potential missed survivors among candidates for prehospital termination of resuscitation. Further investigation to address these difficulties is warranted for better end-of-life care of patients with OHCA.

Association Between Defibrillation Using LIFEPAK 15 or ZOLL X Series and Survival Outcomes in Out-of-Hospital Cardiac Arrest: A Nationwide Cohort Study.

BACKGROUND: Defibrillation is essential for achieving return of spontaneous circulation (ROSC) following out-of-hospital cardiac arrest (OHCA) with shockable rhythms. This study aimed to investigate if the type of defibrillator used was associated with ROSC in OHCA. METHODS AND RESULTS: This study included adult patients with OHCA from the Danish Cardiac Arrest Registry from 2016 to 2021 with at least 1 defibrillation by the emergency medical services. We used multivariable logistic regression and a difference-in-difference analysis, including all patients with or without emergency medical services shock to assess the causal inference of using the different defibrillator models (LIFEPAK or ZOLL) for OHCA defibrillation. Among 6516 patients, 77% were male, the median age (quartile 1; quartile 3) was 70 (59; 79), and 57% achieved ROSC. In total, 5514 patients (85%) were defibrillated using LIFEPAK (ROSC: 56%) and 1002 patients (15%) were defibrillated using ZOLL (ROSC: 63%). Patients defibrillated using ZOLL had an increased adjusted odds ratio (aOR) for ROSC compared with LIFEPAK (aOR, 1.22 [95% CI, 1.04-1.43]). There was no significant difference in 30-day mortality (aOR, 1.11 [95% CI, 0.95-1.30]). Patients without emergency medical services defibrillation, but treated by ZOLL-equipped emergency medical services, had a nonsignificant aOR for ROSC compared with LIFEPAK (aOR, 1.10 [95% CI, 0.99-1.23]) and the difference-in-difference analysis was not statistically significant (OR, 1.10 [95% CI, 0.91-1.34]). CONCLUSIONS: Defibrillation using ZOLL X Series was associated with increased odds for ROSC compared with defibrillation using LIFEPAK 15 for patients with OHCA. However, a difference-in-difference analysis suggested that other factors may be responsible for the observed association.

Impact of Updating the Cardiopulmonary Resuscitation Guidelines on Out-of-Hospital Shockable Cardiac Arrest: A Population-Based Cohort Study in Japan.

BACKGROUND: International consensus on cardiopulmonary resuscitation (CPR) and emergency cardiovascular care science and treatment recommendations (CoSTR) have reported updates on CPR maneuvers every 5 years since 2000. However, few national population-based studies have investigated the comprehensive effectiveness of those updates for out-of-hospital cardiac arrest due to shockable rhythms. The primary objective of the present study was to determine whether CPR based on CoSTR 2005 or 2010 was associated with improved outcomes in Japan, as compared with CPR based on Guidelines 2000. METHODS AND RESULTS: From the All-Japan Utstein Registry between 2005 and 2015, we included 73 578 adults who had shockable out-of-hospital cardiac arrest witnessed by bystanders or emergency medical service responders. The study outcomes over an 11-year period were compared between 2005 of the Guidelines 2000 era, from 2006 to 2010 of the CoSTR 2005 era, and from 2011 to 2015 of the CoSTR 2010 era. In the bystander-witnessed group, the adjusted odds ratios for favorable neurological outcomes at 30 days after out-of-hospital cardiac arrest by enrollment year increased year by year (1.19 in 2006, and 3.01 in 2015). Similar results were seen in the emergency medical service responder-witnessed group and several subgroups. CONCLUSIONS: Compared with CPR maneuvers for shockable out-of-hospital cardiac arrest recommended in the Guidelines 2000, CPR maneuver updates in CoSTR 2005 and 2010 were associated with improved neurologically intact survival year by year in Japan. Increased public awareness and greater dissemination of basic life support may be responsible for the observed improvement in outcomes. REGISTRATION: URL: https://www.umin.ac.jp/ctr/; Unique identifier: 000009918.

Outcome prediction in comatose cardiac arrest patients with initial shockable and non-shockable rhythms.

BACKGROUND: Prognosis after out-of-hospital cardiac arrest (OHCA) is presumed poorer in patients with non-shockable than shockable rhythms, frequently leading to treatment withdrawal. Multimodal outcome prediction is recommended 72 h post-arrest in still comatose patients, not considering initial rhythms. We investigated accuracy of outcome predictors in all comatose OHCA survivors, with a particular focus on shockable vs. non-shockable rhythms. METHODS: In this observational NORCAST sub-study, patients still comatose 72 h post-arrest were stratified by shockable vs. non-shockable rhythms for outcome prediction analyzes. Good outcome was defined as cerebral performance category 1-2 within 6 months. False positive rate (FPR) was used for poor and sensitivity for good outcome prediction accuracy. RESULTS: Overall, 72/128 (56%) patients with shockable and 12/50 (24%) with non-shockable rhythms had good outcome (p < .001). For poor outcome prediction, absent pupillary light reflexes (PLR) and corneal reflexes (clinical predictors) 72 h after sedation withdrawal, PLR 96 h post-arrest, and somatosensory evoked potentials (SSEP), all had FPR <0.1% in both groups. Unreactive EEG and neuron-specific enolase (NSE) >60 µg/L 24-72 h post-arrest had better precision in shockable patients. For good outcome, the clinical predictors, SSEP and CT, had 86%-100% sensitivity in both groups. For NSE, sensitivity varied from 22% to 69% 24-72 h post-arrest. The outcome predictors indicated severe brain injury proportionally more often in patients with non-shockable than with shockable rhythms. For all patients, clinical predictors, CT, and SSEP, predicted poor and good outcome with high accuracy. CONCLUSION: Outcome prediction accuracy was comparable for shockable and non-shockable rhythms. PLR and corneal reflexes had best precision 72 h after sedation withdrawal and 96 h post-arrest.

Risk factors for poor prognosis in patients with extracorporeal cardiopulmonary resuscitation / 中华急诊医学杂志

Objective:To analyze the clinical characteristics of patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR), and to explore the risk factors leading to poor prognosis.Methods:The clinical data of 95 patients with ECPR admitted to the First Affiliated Hospital of Zhengzhou University from January 2020 to May 2023 were retrospectively analyzed. According to the survival status at the time of discharge, the patients were divided into the survival group and death group. The difference of clinical data between the two groups was compared to explore the risk factors related to death and poor prognosis. Risk factors associated with death were identified by Binary Logistic regression analysis. Results:A total of 95 patients with ECPR were included in this study, 62 (65.3%) died and 33 (34.7%) survived at discharge. Patients in the death group had longer low blood flow time [40 (30, 52.5) min vs. 30 (24.5, 40) min ] and total cardiac arrest time[40 (30, 52.5) min vs. 30(24.5, 40) min], shorter total hospital stay [3 (2, 7.25) d vs. 19 (13.5, 31) d] and extracorporeal membrane oxygenation (ECMO) assisted time [26.5 (17, 50) h vs. 62 (44, 80.5) h], and more IHCA patients (56.5% vs. 33.3%) and less had spontaneous rhythm recovery before ECMO (37.1% vs. 84.8%). Initial lactate value [(14.008 ± 5.188) mmol/L vs.(11.23 ± 4.718) mmol/L], APACHEⅡ score [(30.10 ± 7.45) vs. (25.88 ± 7.68)] and SOFA score [12 (10.75, 16) vs. 10 (9.5, 13)] were higher ( P< 0.05). Conclusions:No spontaneous rhythm recovery before ECMO, high initial lactic acid and high SOFA score are independent risk factors for poor prognosis in ECPR patients.

Application of the TiPS65 score for out-of-hospital cardiac arrest patients with initial non-shockable rhythm treated with ECPR.

Background: The TiPS65 score is a validated scoring system used to predict neurological outcomes in out-of-hospital cardiac arrest (OHCA) patients with shockable rhythm treated with extracorporeal cardiopulmonary resuscitation (ECPR). This study aimed to assess the predictive performance of the TiPS65 score in OHCA patients with initial non-shockable rhythm treated with ECPR. Methods: This was a secondary analysis using the JAAM-OHCA registry, a multicenter prospective cohort study. The study included adult OHCA patients with initial non-shockable rhythm who underwent ECPR. The TiPS65 score assigned one point to each of four variables: time to hospital ≤25 minutes, pH value ≥7.0 on initial blood gas assessment, shockable on hospital arrival, and age younger than 65 years. Based on the sum score, the predictive performance for 1-month survival and favorable neurological outcomes, defined as the Cerebral Performance Category 1 or 2, was evaluated. Results: Among 57,754 patients in the registry, 370 were included in the analysis. The overall one-month survival and favorable neurological outcome were 11.1% (41/370) and 4.2% (15/370), respectively. The 1-month survival rates based on the TiPS65 score were as follows: 11.2% (12/107) for 0 points, 9.3% (14/150) for 1 point, 10.0% (9/90) for 2 points, and 26.1% (6/23) for ≥3 points. Similarly, the 1-month favorable neurological outcomes were: 5.6% (6/107) for 0 points, 2.7% (4/150) for 1 point, 4.4% (4/90) for 2 points, and 4.3% (1/23) for ≥3 points. The area under the curve was 0.535 (95% CI: 0.437-0.630) for 1-month survival and 0.530 (95% CI: 0.372-0.683) for 1-month neurological outcome. Conclusion: This study demonstrates that the TiPS65 score has limited prognostic performance among OHCA patients with initial non-shockable rhythm treated with ECPR. Further research is warranted to develop a predictive tool specifically focused on OHCA with initial non-shockable rhythm to aid in determining candidates for ECPR.

Different neuroprognostication thresholds of neuron-specific enolase in shockable and non-shockable out-of-hospital cardiac arrest: a prospective multicenter observational study in Korea (the KORHN-PRO registry).

BACKGROUND: Serum neuron-specific enolase (NSE) is the only recommended biomarker for multimodal prognostication in postcardiac arrest patients, but low sensitivity of absolute NSE threshold limits its utility. This study aimed to evaluate the prognostic performance of serum NSE for poor neurologic outcome in out-of-hospital cardiac arrest (OHCA) survivors based on their initial rhythm and to determine the NSE cutoff values with false positive rate (FPR) < 1% for each group. METHODS: This study included OHCA survivors who received targeted temperature management (TTM) and had serum NSE levels measured at 48 h after return of spontaneous circulation in the Korean Hypothermia Network, a prospective multicenter registry from 22 university-affiliated teaching hospitals in South Korea between October 2015 and December 2018. The primary outcome was poor outcome at 6 month, defined as a cerebral performance category of 3-5. RESULTS: Of 623 patients who underwent TTM with NSE measured 48 h after the return of spontaneous circulation, 245 had an initial shockable rhythm. Median NSE level was significantly higher in the non-shockable group than in the shockable group (104.6 [40.6-228.4] vs. 25.9 [16.7-53.4] ng/mL, P < 0.001). Prognostic performance of NSE assessed by area under the receiver operating characteristic curve to predict poor outcome was significantly higher in the non-shockable group than in the shockable group (0.92 vs 0.86). NSE cutoff values with an FPR < 1% in the non-shockable and shockable groups were 69.3 (sensitivity of 42.1%) and 102.7 ng/mL (sensitivity of 76%), respectively. CONCLUSION: NSE prognostic performance and its cutoff values with FPR < 1% for predicting poor outcome in OHCA survivors who underwent TTM differed between shockable and non-shockable rhythms, suggesting postcardiac arrest survivor heterogeneity. Trial registration KORHN-PRO, NCT02827422. Registered 11 September 2016-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02827422.

Evaluation of junior doctors' retention of knowledge and skills after simulation training in shockable rhythm cardiac arrest in a low-resource setting in Nepal.

Aims: To test junior doctors' abilities to retain advanced life support psychomotor skills and theoretical knowledge in management of shockable rhythm cardiac arrest. Methods: A repeated measure pre-post study design was used with 43 junior doctors, recruited after notifying them with robust method of attraction through flyers, brochures, email and phone calls. Written and performance tests, initial pre-test, immediate post-training, 30-days post-training and 60-days post-training, using simulation-based scenarios with a low-fidelity manikin were used with recording performance of ALS. Instrumentation: Resuscitation Council UK ALS algorithms and guidelines1 were used in a simulated testing environment. Results: There was a highly significant improvement in knowledge immediately after training (p < 0.00), with a net gain of marks from a mean value of 63.2% before training to 87.7% after training by 24.5% (95% CI 19.4, 29.6).There was a gradual decline of retained knowledge with time from immediate post-training over, 30-days and 60-days post-training (p < 0.00). The simulation pre-training assessments and immediate post-training assessments results were statistically significant (p < .00). The mean difference was 44.1% (95% CI 50.11, 38.10). There was a statistically significant decline of the competency with time (p < .00). Unlike for the knowledge test, the drop was significant on the 30th day (p < .00) with a mean difference of -10.5% (95% CI -13.55, -7.40). Conclusion: The training of junior doctors in shockable rhythm cardiac arrest in a low resource setting, improved knowledge and skills in the participants after training. However, retention of knowledge declined at 30 days and more significantly after 60 days and retention of skill was declined more significantly at 30 days.

Non-shockable rhythms: A parametric model for the immediate probability of return of spontaneous circulation.

BACKGROUND: Cardiac arrest can present with asystole, Pulseless Electrical Activity (PEA), or Ventricular Fibrillation/Tachycardia (VF/VT). We investigated the transition intensity of Return of spontaneous circulation (ROSC) from PEA and asystole during in-hospital resuscitation. MATERIALS AND METHODS: We included 770 episodes of cardiac arrest. PEA was defined as ECG with >12 QRS complexes per min, asystole by an isoelectric signal >5 seconds. The observed times of PEA to ROSC transitions were fitted to five different parametric time-to-event models. At values ≤0.1, transition intensities roughly represent next-minute probabilities allowing for direct interpretation. Different entities of PEA and asystole, dependent on whether it was the primary or a secondary rhythm, were included as covariates. RESULTS: The transition intensities to ROSC from primary PEA and PEA after asystole were unimodal with peaks of 0.12 at 3 min and 0.09 at 6 min, respectively. Transition intensities to ROSC from PEA after VF/VT, or following transient ROSC, exhibited high initial values of 0.32 and 0.26 at 3 minutes, respectively, but decreased. The transition intensity to ROSC from initial asystole and asystole after PEA were both about 0.01 and 0.02; while asystole after VF/VT had an intensity to ROSC of 0.15 initially which decreased. The transition intensity from asystole after temporary ROSC was constant at 0.08. CONCLUSION: The immediate probability of ROSC develops differently in PEA and asystole depending on the preceding rhythm and the duration of the resuscitation attempt. This knowledge may aid simple bedside prognostication and electronic resuscitation algorithms for monitors/defibrillators.

Seasonal Variation in the Incidence of In-Hospital Cardiac Arrest.

BACKGROUND: Seasonal variation in cardiovascular outcomes, including out-of-hospital cardiac arrest, has been described. OBJECTIVES: This study aimed to investigate seasonal differences in the incidence of in-hospital cardiac arrest (IHCA) and associated mortality. METHODS: Using National Inpatient Sample data from 2005 to 2019, we determined the incidence of IHCA in 4 seasons. The primary objective was to evaluate overall seasonal trends in the incidence of IHCA and trends stratified by sex, age, and region. The secondary aim was to determine common causes of admission that led to IHCA, differences in those with shockable vs nonshockable IHCA, independent predictors of IHCA, and seasonal variation in IHCA-related in-hospital mortality and length of stay. RESULTS: A consistent winter peak was observed in the incidence of IHCA in both male and female patients over the years in all age groups except young (<45 years) and in all regions. In 2019, both unadjusted and risk-adjusted odds of IHCA were higher (OR: 1.13; P < 0.001; adjusted OR: 1.08; P = 0.033) in winter than in summer. Patients with shockable IHCA were mainly admitted for cardiac and those with nonshockable IHCA for noncardiac conditions. No seasonal variation was observed in in-hospital mortality after IHCA. Therefore, seasonal variation exists, with a higher IHCA event rate in winter than summer. CONCLUSIONS: Improving insights into factors that influence the higher IHCA event rate during winter may help with proper resource allocation, development of strategies for early recognition of patients vulnerable to IHCA, and closer monitoring and optimization of care to prevent IHCA and improve outcomes.

Deep Learning Strategy for Sliding ECG Analysis during Cardiopulmonary Resuscitation: Influence of the Hands-Off Time on Accuracy.

This study aims to present a novel deep learning algorithm for a sliding shock advisory decision during cardiopulmonary resuscitation (CPR) and its performance evaluation as a function of the cumulative hands-off time. We retrospectively used 13,570 CPR episodes from out-of-hospital cardiac arrest (OHCA) interventions reviewed in a period of interest from 30 s before to 10 s after regular analysis of automated external defibrillators (AEDs). Three convolutional neural networks (CNNs) with raw ECG input (duration of 5, 10, and 15 s) were applied for the shock advisory decision during CPR in 26 sequential analyses shifted by 1 s. The start and stop of chest compressions (CC) can occur at arbitrary times in sequential slides; therefore, the sliding hands-off time (sHOT) quantifies the cumulative CC-free portion of the analyzed ECG. An independent test with CPR episodes in 393 ventricular fibrillations (VF), 177 normal sinus rhythms (NSR), 1848 other non-shockable rhythms (ONR), and 3979 asystoles (ASYS) showed a substantial improvement of VF sensitivity when increasing the analysis duration from 5 s to 10 s. Specificity was not dependent on the ECG analysis duration. The 10 s CNN model presented the best performance: 92-94.4% (VF), 92.2-94% (ASYS), 96-97% (ONR), and 98.2-99.5% (NSR) for sliding decision times during CPR; 98-99% (VF), 98.2-99.8% (ASYS), 98.8-99.1 (ONR), and 100% (NSR) for sliding decision times after end of CPR. We identified the importance of sHOT as a reliable predictor of performance, accounting for the minimal sHOT interval of 2-3 s that provides a reliable rhythm detection satisfying the American Heart Association (AHA) standards for AED rhythm analysis. The presented technology for sliding shock advisory decision during CPR achieved substantial performance improvement in short hands-off periods (>2 s), such as insufflations or pre-shock pauses. The performance was competitive despite 1-2.8% point lower ASYS detection during CPR than the standard requirement (95%) for non-noisy ECG signals. The presented deep learning strategy is a basis for improved CPR practices involving both continuous CC and CC with insufflations, associated with minimal CC interruptions for reconfirmation of non-shockable rhythms (minimum hands-off time) and early treatment of VF (minimal pre-shock pauses).

Impact of sex and role of coronary artery disease in out-of-hospital cardiac arrest presenting with refractory ventricular arrhythmias.

Introduction: There are limited data on sex-related differences in out-of hospital cardiac arrests (OHCAs) with refractory ventricular arrhythmias (VA) and, in particular, about their relationship with cardiovascular risk profile and severity of coronary artery disease (CAD). Purpose: Aim of this study was to characterize sex-related differences in clinical presentation, cardiovascular risk profile, CAD prevalence, and outcome in OHCA victims presenting with refractory VA. Methods: All OHCAs with shockable rhythm that occurred between 2015 and 2019 in the province of Pavia (Italy) and in the Canton Ticino (Switzerland) were included. Results: Out of 680 OHCAs with first shockable rhythm, 216 (33%) had a refractory VA. OHCA patients with refractory VA were younger and more often male. Males with refractory VA had more often a history of CAD (37% vs. 21%, p 0.03). In females, refractory VA were less frequent (M : F ratio 5 : 1) and no significant differences in cardiovascular risk factor prevalence or clinical presentation were observed. Male patients with refractory VA had a significantly lower survival at hospital admission and at 30 days as compared to males without refractory VA (45% vs. 64%, p < 0.001 and 24% vs. 49%, p < 0.001, respectively). Whereas in females, no significant survival difference was observed. Conclusions: In OHCA patients presenting with refractory VA the prognosis was significantly poorer for male patients. The refractoriness of arrhythmic events in the male population was probably due to a more complex cardiovascular profile and in particular due to a pre-existing CAD. In females, OHCA with refractory VA were less frequent and no correlation with a specific cardiovascular risk profile was observed.

Targeted Temperature Management in Cardiac Arrest: An Updated Narrative Review.

The established benefits of cooling along with development of sophisticated methods to safely and precisely induce, maintain, monitor, and reverse hypothermia have led to the development of targeted temperature management (TTM). Early trials in human subjects showed that hypothermia conferred better neurological outcomes when compared to normothermia among survivors of cardiac arrest, leading to guidelines recommending targeted hypothermia in this patient population. Multiple studies have sought to explore and compare the benefit of hypothermia in various subgroups of patients, such as survivors of out-of-hospital cardiac arrest versus in-hospital cardiac arrest, and survivors of an initial shockable versus non-shockable rhythm. Larger and more recent trials have shown no statistically significant difference in neurological outcomes between patients with targeted hypothermia and targeted normothermia; further, aggressive cooling is associated with a higher incidence of multiple systemic complications. Based on this data, temporal trends have leaned towards using a lenient temperature target in more recent times. Current guidelines recommend selecting and maintaining a constant target temperature between 32 and 36 °C for those patients in whom TTM is used (strong recommendation, moderate-quality evidence), as soon as possible after return of spontaneous circulation is achieved and airway, breathing (including mechanical ventilation), and circulation are stabilized. The comparative benefit of lower (32-34 °C) versus higher (36 °C) temperatures remains unknown, and further research may help elucidate this. Any survivor of cardiac arrest who is comatose (defined as unarousable unresponsiveness to external stimuli) should be considered as a candidate for TTM regardless of the initial presenting rhythm, and the decision to opt for targeted hypothermia versus targeted normothermia should be made on a case-by-case basis.