Optimal cardiopulmonary resuscitation duration for favorable neurological outcomes after out-of-hospital cardiac arrest

Background A favorable neurological outcome is closely related to patient characteristics and total cardiopulmonary resuscitation (CPR) duration. The total CPR duration consists of pre-hospital and in-hospital durations. To date, consensus is lacking on the optimal total CPR duration. Therefore, this study aimed to determine the upper limit of total CPR duration, the optimal cut-off time at the pre-hospital level, and the time to switch from conventional CPR to alternative CPR such as extracorporeal CPR. Methods We conducted a retrospective observational study using prospective, multi-center registry of out-of-hospital cardiac arrest (OHCA) patients between October 2015 and June 2019. Emergency medical service–assessed adult patients (aged ≥ 18 years) with non-traumatic OHCA were included. The primary endpoint was a favorable neurological outcome at hospital discharge. Results Among 7914 patients with OHCA, 577 had favorable neurological outcomes. The optimal cut-off for pre-hospital CPR duration in patients with OHCA was 12 min regardless of the initial rhythm. The optimal cut-offs for total CPR duration that transitioned from conventional CPR to an alternative CPR method were 25 and 21 min in patients with initial shockable and non-shockable rhythms, respectively. In the two groups, the upper limits of total CPR duration for achieving a probability of favorable neurological outcomes < 1% were 55–62 and 24–34 min, respectively, while those for a cumulative proportion of favorable neurological outcome > 99% were 43–53 and 45–71 min, respectively. Conclusions Herein, we identified the optimal cut-off time for transitioning from pre-hospital to in-hospital settings and from conventional CPR to alternative resuscitation. Although there is an upper limit of CPR duration, favorable neurological outcomes can be expected according to each patient’s resuscitation-related factors, despite prolonged CPR duration.

Outcomes of Early versus Late Endotracheal Intubation in Patients with Initial Non-Shockable Rhythm Cardiopulmonary Arrest in the Emergency Department

Background. Sudden cardiac arrest is a critical condition in the emergency department (ED). Currently, there is no considerable evidence supporting the best time to complete advanced airway management (AAM) with endotracheal intubation in cardiac arrest patients presented with initial non-shockable cardiac rhythm. Objectives. To compare survival to hospital discharge and discharge with favorable neurological outcome between the ED cardiac arrest patients who have received AAM with endotracheal intubation within 2 minutes (early AAM group) and those over 2 minutes (late AAM group) after the start of chest compression in ED. Methods. We conducted a retrospective cohort study involving the ED cardiac arrest patients who presented with initial non-shockable rhythm in ED. Multivariable logistic regression analysis was used to evaluate the independent effect of early AAM on outcomes. The outcomes included the survival to hospital discharge and discharge with favorable neurological outcome. Results. There were 416 eligible participants: 209 in the early AAM group and 207 participants in the late AAM group. The early AAM group showed higher survival to hospital discharge compared with the late AAM group, but no statistically significant difference (adjusted odds ratio (aOR): 1.28, 95% confidence interval (CI): 0.59 -2.76, p = 0.524 ). Discharge with favorable neurological outcome is also higher in the early AAM group (aOR: 1.68, 95% CI, 0.52 -5.45, p = 0.387 ). Conclusion. This study did not demonstrate a significant improvement of survival to hospital discharge and discharge with favorable neurological outcome in the ED cardiac arrest patients with initial non-shockable cardiac arrest who underwent early AAM within two minutes. More research is needed on the timing of AAM and on airway management strategies to improve survival.

Giant occipital encephalocele: a case report, surgical and anesthetic challenge and review of literature

Background An encephalocele is a congenital neural tube defect characterized by herniation of cranial contents through a defect in the cranium and is caused by failure of the closure of the cranial part of the developing neural tube. An encephalocele is termed as “giant encephalocele” when the size of encephalocele is larger than the size of the head. They depend on size of the sac, percentage of neural tissue content, hydrocephalus, infection, and other associated pathologies for a favorable neurological outcome. Case presentation We report a case of a four-month-old boy with a giant occipital encephalocele measuring 21 × 15 × 19 cm in size, which was a surgical and anesthetic challenge for us. Intubation was achieved in lateral position. Part of occipital and cerebellar parenchyma was present in the sac and bony defect was approximately 2.5 cm in occipital bone in midline. We performed surgical excision and repair with a good overall outcome. Conclusion Perioperative management of a giant occipital encephalocele is a challenge for both anesthesiologists and neurosurgeons. Managing such a case demands a search for other congenital abnormalities, expertise in handling airway, and proper intraoperative care. Careful planning and perioperative management are essential for a successful outcome.

Abstract 12052: A Comprehensive Simulation-Based Training for E-CPR Improves the Neurological Outcome of Patients With Refractory Cardiac Arrest

Background: Extracorporeal cardiopulmonary resuscitation (E-CPR) has been utilized as a rescue strategy for patients with refractory cardiac arrest (CA). To improve the outcome of E-CPR, we developed a comprehensive simulation-based E-CPR training program. In the present study we assessed whether the E-CPR training improved the mortality and the neurological outcome. Methods: We have implemented the comprehensive E-CPR simulation training program twice a year to the medical team, which consists of emergency physicians, cardiologists, nurses, clinical engineers, and radiographers using a mock vascular model for E-CPR (ECMO cannulation). We assessed collapse to ECMO time, cumulative 30-day survival and good neurological outcome at hospital discharge defined as the cerebral performance categories (CPC) of 1 or 2. Results: Fifty-three consecutive patients received E-CPR for OHCA from January 2012 to December 2020 in which 31 patients were prior to (until September 2017) and 22 were after (from October 2017) the initiation of the E-CPR training. No differences were found in age, rates of witnessed and bystander-CPR, shockable rhythms, or acute coronary syndrome (ACS). Intra-aortic balloon pump was used in 87% patients prior to and 27% patients after the training (p<0.001), and a microaxial Impella pump was used in 55% after the training. Collapse to ECMO time was significantly shorter after the training (p<0.001). Cumulative 30-day survival and the rate of favorable neurological outcome were significantly higher after the training (p<0.05). Multivariate cox proportional hazard analysis revealed that age (hazard ratio [HR], 1.38 (10 years increase), 95% confidence interval [CI], 1.12-1.73, p=0.002), Collapse to ECMO time (HR, 1.14, 95%CI, 1.04-1.23, p=0.006), and additional Impella use (HR, 0.23, 95% CI, 0.08-0.69, p=0.0009) were significantly associated with the 30-day survival. Conclusions: The E-CPR training significantly improved the collapse to ECMO time. The faster deployment of ECMO improves the neurological outcome and 30-day survival in patients with refractory CA. Additional use of Impella may improve the survival.

Abstract 9450: Shockable Rhythm at Hospital Arrival as the Predictor of Favorable Neurological Outcome in Out-of-Hospital Cardiac Arrest Patients Receiving Extracorporeal Cardiopulmonary Resuscitation

Introduction: For OHCA patients without ROSC under standard ALS, extracorporeal cardiopulmonary resuscitation (ECPR) was the only chance. However, ECPR was invasive and costed tremendous resources. This study aimed to analyze the predictor of favorable neurological outcome at hospital discharge (FO, cerebral performance category 1-2). Hypothesis: In OHCA patients receiving ECPR, shockable rhythm at hospital arrival could serve as predictor of FO. Method: This was a single center retrospective study which enrolled 126 OHCA patients receiving ECPR between January 2012 to December 2019. Primary outcome was FO at hospital discharge. Predictors of FO were assessed by multiple logistic regression. Patients with initial shockable rhythm were analyzed according to the cardiac rhythm at hospital arrival. Result: Among OHCA patients receiving ECPR, FO at hospital discharge was 21%. Certain variables were associated with FO: witnessed collapse (P=0.014), bystander CPR (P=0.05), shorter no flow time(P=0.008), and shockable rhythm at hospital arrival (78% vs. 49%;P=0.009). Initial shockable rhythm did not differ significantly (85% vs. 71% ;P=0.15). Multiple logistic regression showed that shockable rhythm at hospital arrival was the only predictor of FO (OR, 3.012; 95% CI, 1.06-8.53; P=0.038). Patients with initial shockable rhythm represented a heterogenous group. The group with shockable rhythm at hospital arrival had 30% of FO, which was significantly higher than 17% in PEA group, and 6% in asystole group (Graph 1). Patients who remained shockable had higher percentage of witnessed arrest, shorter arrest-hospital time, less metabolic disturbance, and hence higher percentage of FO. Conclusion: In OHCA patients receiving ECPR, shockable rhythm at hospital arrival could predict favorable neurological outcome at discharge more precisely than initial shockable rhythm. ECPR selection criteria should take the rhythm at hospital arrival into consideration.

Abstract 8875: Early Compared to Late Administration of Epinephrine in Adults With Shockable Initial Rhythm Out-of-Hospital Cardiac Arrest

Introduction: The optimal timing of epinephrine administration in shockable initial rhythm out-of-hospital cardiac arrest (OHCA) is unclear. Hypothesis: Early compared to late epinephrine following first electrical defibrillation attempt is associated with better outcomes in shockable initial rhythm OHCA. Methods: We conducted a retrospective study in adults with shockable initial rhythm OHCA from 2011-2015 in North America. We used multivariable logistic regression to assess associations between timing of epinephrine and prehospital return of spontaneous circulation (ROSC), survival to hospital discharge, and hospital discharge with favorable neurological outcome (modified Rankin Scale score≤3). We used propensity-score-matching and subgroup analyses to assess robustness of associations. Results: Of 6416 patients, median age was 64 (IQR: 54-74) years, 5136 (80%) were men, 2226 (35%) received epinephrine within four minutes after first defibrillation, 5119 (80%), 1237 (19%), and 996 (16%) had prehospital ROSC, survival to hospital discharge, and favorable neurological outcome at discharge respectively. Adjusted for confounders, we observed lower odds of prehospital ROSC (OR=0.95, 95%CI 0.94-0.96; p<0.001), survival to hospital discharge (OR=0.91, 95%CI 0.89-0.92; p<0.001), and favorable neurological outcomes at discharge (OR=0.92, 95%CI 0.90-0.93; p<0.001) per minute later epinephrine administration. Compared to epinephrine administration within four minutes following first defibrillation attempt, later epinephrine was associated with lower odds of prehospital ROSC (OR=0.58, 95%CI 0.51-0.68; p<0.001), survival to hospital discharge (OR=0.50, 95%CI 0.43-0.58; p<0.001), and favorable neurological outcome at discharge (OR=0.51, 95%CI 0.43-0.59; p<0.001). Associations remained significant in a well-balanced propensity score matched cohort and subgroup analyses by witness status, EMS response time, and total epinephrine dose. Conclusion: In shockable initial rhythm OHCA, early compared to late epinephrine administration following first defibrillation attempt was associated with better odds of prehospital ROSC, survival to hospital discharge, and hospital discharge with favorable neurological outcome.

Abstract 14159: Characteristics and Outcomes in COVID-19 Pediatric In-Hospital Cardiac Arrest Patients

Introduction: Survival of adult patients with COVID-19 who had an in-hospital cardiac arrest (IHCA) are poor. Characteristics and outcomes for pediatric IHCA patients with COVID-19 are unknown. Hypothesis: We hypothesized that pediatric COVID-19 patients would have worse survival outcomes when compared to non-COVID patients. Methods: A multicenter, multinational cohort of pediatric IHCA in the pediRES-Q collaborative were reviewed (March 1, 2020 - April 1, 2021). We characterized patients with COVID-19 compared to patients without COVID-19 and investigated whether COVID-19 was associated with survival outcomes using multivariate logistic regression with mixed effects. Results: We identified 362 pediatric IHCAs of which 14 were COVID-19 positive. For non-COVID-19 vs COVID-19 patients respectively, median [Q1; Q3] age was 1.0 [0.3; 7.1] vs. 7.1 [1.5; 14.0] years and 42% vs. 43% were female. Immediate cause of arrest was hypotension: 8% vs. 43%, respiratory decompensation: 19% vs. 21%, and hypoxia 22% vs. 36% for non-COVID-19 vs. COVID-19 patients. For non-COVID-19 vs COVID-19 patients, total CPR duration was 10 [4; 33] min vs 19 [5; 33] min (for non-return of spontaneous circulation (ROSC) cases only: 35 [20; 55] min vs 34 [24; 34] min). For non-COVID-19 vs COVID-19 patients, ROSC was 79% vs. 57%, aOR: 0.48 (95% CI: 0.24-0.98), survival to hospital discharge was 45% vs. 29%, aOR: 0.63 (95% CI: 0.25-1.57) and survival with favorable neurological outcome was 39% vs. 21%, aOR: 0.51 (95% CI: 0.16-1.65). Conclusions: In a pediatric resuscitation quality improvement collaborative, pediatric IHCA patients with COVID-19 were older when compared to non-COVID-19 patients. Median CPR duration was >30 minutes for COVID-19 non-survivors, COVID-19 patients had lower chance of ROSC when compared to non-COVID-19 patients but considerably better survival outcomes than those reported for adults.

Abstract 11034: Extracorporeal Life-Support for Out-of-Hospital Cardiac Arrest: A Nationwide Multicenter Study

Introduction: Despite promising survival and favorable neurological results in IHCA, the outcomes of ECLS for OHCA are more heterogeneous. The clinical setting for the survival and favorable neurological outcomes of ECLS in OHCA may differ from that in IHCA. Hypothesis: This study aimed to determine whether ECLS is associated with improved survival to hospital discharge with favorable neurological outcome compared to conventional cardiopulmonary resuscitation and identify in which OHCA patients the implementation of ECLS would be beneficial. Methods: The clinical outcome of OHCA treated by ECLS or CCPR between 2015 and 2020 was retrospectively investigated using KoCARC, a nationwide multicenter OHCA registry of Korea. Differences in baseline clinical characteristics were adjusted by matching propensity for ECLS. Primary outcome was 30-day survival with neurologically favorable status of cerebral performance category of 1 or 2. Restricted mean survival time (RMST) was used to compare outcome between groups. Result: Of 12,006 patients (mean age=71, male gender=65%) included, ECLS was performed in 272 patients (2.2%). In unadjusted analysis, the frequency of survival with favorable neurological status was higher in ECLS compared to CCPR (15% versus 7%, RMST 9.4 versus 3.8 days, p<0.001). Subgroup analysis revealed that the benefit of ECLS was evident in high-risk groups including initial non-shockable rhythm or CPR duration≥20 min (p<0.05, all). In analysis of propensity score-matched 271 pairs, there was no difference in the clinical outcome between ECLS and CCPR (15% versus 16%, RMST 9.4 versus 9.0 days, p=0.33), but ECLS was still better than CCPR in initial non-shockable rhythm or CPR duration≥20 min (p<0.05, all). Conclusions: In this real-world data analysis, ECLS compared to CCPR did not result in better clinical outcome of OHCA in overall. However, ECLS might be beneficial for high-risk patients such as initial non-shockable rhythm or CPR duration≥20 min.

Abstract 12464: Signs of Life as a Predictor of Survival in Patients With Out-of-Hospital Cardiac Arrest and Long Low-Flow Times

Introduction: Long low-flow times in patients with out-of-hospital cardiac arrest (OHCA) are associated with poor outcome. Signs of life during cardiopulmonary resuscitation (CPR) is a simple method to evaluate in the field, but little is known about its impact on survival in patients with long low-flow times. Hypothesis: Thirty-day survival in OHCA patients with long prehospital low-flow times is higher in patients with signs of life during CPR than in patients with no signs of life during CPR. Methods: Observational, retrospective, single center study of OHCA patients referred to a tertiary cardiac arrest center in the Central Demark Region from 2015-2018. Risk factors were assessed by univariate logistic regression. Comparisons were made by Kaplan-Meier survival curves and log-rank test. Results: In a cohort of 807 patients with OHCA, 30-day survival was seen in 364 (45%). Among patients discharged from hospital, favorable neurological outcome with CPC 1-2 was observed in 93%. Signs of life during CPR was present in 315 (39%) patients. Risk of 30-day mortality was significantly reduced in patients presenting signs of life during CPR (RR 0.25, 95% CI [0.20-0.30]). Poor survival was seen in patients with low-flow times exceeding 30 minutes compared to patients with shorter low-flow times, (11% versus 66%, p < 0.001). In patients with low-flow times > 30 min, the survival rate increased to 33 % in the presence of signs of life during CPR compared to only 3% in patients without signs of life during CPR, p < 0.001. Conclusions: In OHCA patients, low-flow times > 30 minutes were highly associated with poor survival, however signs of life during CPR predicts higher survival both in the overall population and in patients with long low-flow times. Thus, resuscitation efforts may not be futile in patients with long low-flow times presenting signs of life during CPR.

Abstract 12185: Impact of Cardiac Arrest Centers on the Survival of Nontraumatic Out-of-Hospital Cardiac Arrest Patients: A Systematic Review and Meta-Analysis

Introduction: The role of cardiac arrest centers (CAC) in out-of-hospital cardiac arrest (OHCA) is uncertain, especially since CACs are inconsistently defined. This study seeks to address knowledge gaps by assessing the impact of CACs on nontraumatic OHCA patients as a whole and among specific subgroups. Methods: In this review, Medline, Embase, and Cochrane CENTRAL were searched from inception to 9 March 2021. Studies were included if they compared CAC vs non-CAC among adult patients with nontraumatic OHCA. CACs were explicitly named by study authors and were capable of appropriate interventions. Data abstraction and quality assessment were independently conducted by two authors, and a third author resolved discrepancies. Main outcomes were survival and survival with favorable neurological outcome at hospital discharge or at 30 days. Meta-analyses were performed for adjusted (aOR) and crude (OR) odds ratios. Sensitivity analyses were conducted for wider definitions of CAC such as high volume centers or improved post-resuscitation care, and subgroups analysed to account for heterogeneity. Results: The search yielded 4544 articles, and 36 were included for analysis. Survival with favorable neurological outcome significantly improved with treatment at CACs (aOR = 1.88, 95% CI 1.53 to 2.31), even when including high volume centers (aOR = 1.68, 95% CI 1.30 to 2.16), or when including improved care centers (aOR = 2.16, 95% CI 1.76 to 2.64) as CACs. Survival significantly increased with treatment at CAC (aOR = 1.92, 95% CI 1.59 to 2.31), even when including high volume centers (aOR = 1.74, 95% CI 1.38 to 2.18), or when including improved care centers (aOR = 1.97, 95% CI 1.71 to 2.26) as CACs. The effect on favorable neurological outcome was more pronounced among patients with shockable rhythm (p = 0.03) and on survival among patients without prehospital ROSC (p = 0.005). Findings were robust to sensitivity analyses, with no publication bias detected. Conclusion: CACs improved survival and neurological outcomes for nontraumatic OHCA patients despite varying definitions of CAC. Patients with shockable rhythms and without prehospital ROSC appeared to yield greater benefit from CACs. Evidence for bypassing hospitals or inter-hospital transfer remains inconclusive.