Variability of Post-Cardiac Arrest Care Practices Among Cardiac Arrest Centers: United States and South Korean Dual Network Survey of Emergency Physician Research Principal Investigators

Variability in temperature control practices amongst the Influence of Cooling duration on Efficacy in Cardiac Arrest Patients (ICECAP) trial

AIM

Temperature control is a complex bundled intervention; the synergistic impact of each individual component is ill defined and underreported. Resultantly, the influence of parameter optimization on temperature control's overall neuroprotective effect remains poorly understood. To characterize variability in temperature control parameters and barriers to short pre-induction and induction times, we surveyed sites enrolling in an ongoing multicenter clinical trial.

METHODS

This was a cross-sectional, survey study evaluating temperature control practices within the Influence of Cooling duration on Efficacy in Cardiac Arrest Patients (ICECAP) trial (NCT04217551). A 23-question web-based survey (Qualtrics) was distributed to the site principal investigators by email. Respondents were asked about site practices pertaining to the use of temperature control, including the request to upload individual institutional protocols. Open-ended responses were analyzed qualitatively by categorizing responses into identified themes. To complement survey level data, records pertaining to the quality of temperature control were extracted from the ICECAP trial database.

RESULTS

The survey response rate was 75% (n = 51) including 23.5% (n = 12) survey respondents who uploaded institutional protocols. Most sites reported having institutional protocols for temperature control (n = 41; 80%), including 62.5% (n = 32) who had separate protocols for initiation of temperature control in the emergency department (ED). Fewer sites had protocols specific to sedation or neuromuscular blockade (NMB) management (n = 35, 68.6%). Use of NMB during temperature control induction was variable; 61.7% (n = 29) of sites induced paralysis less than 20% of the time. While most institutional protocols (n = 11, 83.3%) commented on the importance of early initiation of temperature control, this was incongruent with the largest reported barrier, which was clinical nihilism regarding the importance of early temperature control initiation (n = 30, 62.5%). Within the ICECAP trial database, 1 in 2 patients were treated with NMB however, use of NMB and time to initiation of temperature control device varied widely between sites.

CONCLUSION

Amongst ICECAP trial sites, there was significant variability in resources, methods, and barriers for early temperature control initiation. Defining and standardizing high-quality temperature control must be prioritized, as it may impact the interpretation of past and current clinical trial findings.

Use of Prognostication Instruments in Prognostication Procedures of Postanoxic Coma Patients over Time: A Retrospective Study

BACKGROUND

Many survivors of cardiovascular arrest remain in a postanoxic coma. The neurologist's task is to provide the most accurate assessment of the patient's neurologic prognosis through a multimodal approach of clinical and technical tests. The aim of this study is to analyze differences and developments in the concept of neurological prognosis assessment and in-hospital outcome of patients over a five year-period.

METHODS

This retrospective observational study included 227 patients with postanoxic coma treated in the medical intensive care unit of the University Hospital, Mannheim from January 2016 to May 2021. We retrospectively analyzed patient characteristics, post-cardiac arrest care, and the use of clinical and technical tests for neurological prognosis assessment and patient outcome.

RESULTS

Over the observation period, 215 patients received a completed neurological prognosis assessment. Regarding the multimodal prognostic assessment, patients with poor prognosis (54%) received significantly fewer diagnostic modalities than patients with very likely poor (20.5%), indeterminate (24.2%), or good prognosis (1.4%; p = 0.001). The update of the DGN guidelines in 2017 had no effect on the number of performed prognostic parameters per patient. The finding of bilaterally absent pupillary light reflexes or severe anoxic injury on CT contributed most to a poor prognosis category (OR 8.38, 95%CI 4.01-7.51 and 12.93, 95%CI 5.55-30.13, respectively), whereas a malignant EEG pattern and NSE > 90 µg/L at 72 h resulted in the lowest OR (5.11, 95%CI 2.32-11.25, and 5.89, 95%CI 3.14-11.06, respectively) for a poor prognosis category. Assessment of baseline NSE significantly increased over the years (OR 1.76, 95%CI 1.4-2.22, p < 0.001), and assessment of follow-up NSE at 72 h trended to increase (OR 1.19, 95%CI 0.99-1.43, p = 0.06). In-hospital mortality was high (82.8%), remained unchanged over the observation period, and corresponded to the number of patients in whom life-sustaining measures were discontinued.

CONCLUSIONS

Among comatose survivors of cardiac arrest, the prognosis remains poor. Prognostication of a poor outcome led nearly exclusively to withdrawal of care. Prognostic modalities varied considerably with regard to their contribution to a poor prognosis category. Increasing enforcement of a standardized prognosis assessment and standardized evaluation of diagnostic modalities are needed to avoid false-positive prognostication of poor outcomes.

A machine learning approach for modeling decisions in the out of hospital cardiac arrest care workflow

BACKGROUND

A growing body of research has shown that machine learning (ML) can be a useful tool to predict how different variable combinations affect out-of-hospital cardiac arrest (OHCA) survival outcomes. However, there remain significant research gaps on the utilization of ML models for decision-making and their impact on survival outcomes. The purpose of this study was to develop ML models that effectively predict hospital's practice to perform coronary angiography (CA) in adult patients after OHCA and subsequent neurologic outcomes.

METHODS

We utilized all (N = 2398) patients treated by the Chicago Fire Department Emergency Medical Services included in the Cardiac Arrest Registry to Enhance Survival (CARES) between 2013 and 2018 who survived to hospital admission to develop, test, and analyze ML models for decisions after return of spontaneous circulation (ROSC) and patient survival. ML classification models, including the Embedded Fully Convolutional Network (EFCN) model, were compared based on their ability to predict post-ROSC decisions and survival.

RESULTS

The EFCN classification model achieved the best results across tested ML algorithms. The area under the receiver operating characteristic curve (AUROC) for CA and Survival were 0.908 and 0.896 respectively. Through cohort analyses, our model predicts that 18.3% (CI 16.4-20.2) of patients should receive a CA that did not originally, and 30.1% (CI 28.5-31.7) of these would experience improved survival outcomes.

CONCLUSION

ML modeling effectively predicted hospital decisions and neurologic outcomes. ML modeling may serve as a quality improvement tool to inform system level OHCA policies and treatment protocols.

Continuous Neuromuscular Blockade Following Successful Resuscitation From Cardiac Arrest: A Randomized Trial

Background

Neuromuscular blockade (NMB) agents are often administered to control shivering during targeted temperature management following cardiac arrest. In this study, we hypothesized that early, continuous NMB would result in a greater reduction in serum lactate levels among comatose patients after cardiac arrest.

Methods and Results

Randomized trial of continuous NMB for 24 hours versus usual care following cardiac arrest conducted at 5 urban centers in the United States. Adult patients who achieved return of spontaneous circulation, remained unresponsive, and underwent targeted temperature management after cardiac arrest were included. The primary outcome was change in lactate over 24 hours. A total of 83 patients were randomized, and 80 were analyzed (37 and 43 in the NMB and usual care arms, respectively). There was no significant interaction between time and treatment group with respect to change in lactate over 24 hours (median lactate change from 4.2 to 2.0 mmol/L [−2.2 mmol/L] in the NMB arm versus 4.0 to 1.7 mmol/L [−2.3 mmol/L] in the usual care arm; geometric mean difference, 1.3 [95% CI, 1.0–1.8]; P=0.07 for the interaction term). There was no difference in hospital survival (38% [NMB] versus 33% [usual care]; P=0.63) or survival with good functional outcome (30% [NMB] versus 21% [usual care]; P=0.35). There were no adverse events in either arm attributed to study interventions.

Conclusions

Continuous NMB compared with usual care did not reduce lactate over the first 24 hours after enrollment compared with usual care. There was no difference in overall hospital survival, hospital survival with good neurologic outcome, or adverse events.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02260258.

Impact of Structured Pathways for Postcardiac Arrest Care: A Systematic Review and Meta-Analysis

OBJECTIVES

Recent research has demonstrated value in selected therapeutic and prognostic interventions delivered to patients following cardiac arrest. The aim of this work was to determine if the implementation of a structured care pathway, which combines different interventions, could improve outcomes in survivors of cardiac arrest.

DATA SOURCES

PubMed and review of citations in retrieved articles.

STUDY SELECTION

Randomized trials and prospective observational studies conducted in adult cardiac arrest patients, which evaluated the impact on outcome of a structured care pathway, defined as an organized set of interventions designed specifically for postcardiac arrest patients.

DATA EXTRACTION

Data collected included study characteristics and methodologic quality, populations enrolled, interventions that were part of the cardiac arrest structured care pathway, and outcomes. The principal outcome was favorable functional status defined as a Cerebral Performance Category score of 1-2 at or after hospital discharge.

DATA SYNTHESIS

The systematic search retrieved 481 articles of which nine (total, 1,994 patients) were selected for systematic review, and six (1,422 patients) met criteria for meta-analysis. Interventions in the care pathways included early coronary angiography with or without percutaneous coronary intervention (eight studies), targeted temperature management (nine studies), and protocolized management in the ICU (seven studies). Neurologic prognostication was not a part of any of the structured pathways. Meta-analysis found significantly higher odds of achieving a favorable functional outcome in patients who were treated in a structured care pathway, when compared with standard care (odds ratio, 2.35; 95% CI, 1.46-3.81).

CONCLUSIONS

Following cardiac arrest, patients treated in a structured care pathway may have a substantially higher likelihood of favorable functional outcome than those who receive standard care. These findings suggest benefit of a highly organized approach to postcardiac arrest care, in which a cluster of evidence-based interventions are delivered by a specialized interdisciplinary team. Given the overall low certainty of evidence, definitive recommendations will need confirmation in additional high-quality studies.

Comparison between Gel Pad Cooling Device and Water Blanket during Target Temperature Management in Cardiac Arrest Patients

Background:

Target temperature management (TTM) improves neurological outcomes for comatose survivors of out-of-hospital cardiac arrest. We compared the efficacy and safety of a gel pad cooling device (GP) and a water blanket (WB) during TTM.

Methods:

We performed a retrospective analysis in a single hospital, wherein we measured the time to target temperature (<34℃) after initiation of cooling to evaluate the effectiveness of the cooling method. The temperature farthest from 33℃ was selected every hour during maintenance. Generalized estimation equation analysis was used to compare the absolute temperature differences from 33℃ during the maintenance period. If the selected temperature was not between 32℃ and 34℃, the hour was considered a deviation from the target. We compared the deviation rates during hypothermia maintenance to evaluate the safety of the different methods.

Results:

A GP was used for 23 patients among of 53 patients, and a WB was used for the remaining. There was no difference in baseline temperature at the start of cooling between the two patient groups (GP, 35.7℃ vs. WB, 35.6℃; P=0.741). The time to target temperature (134.2 minutes vs. 233.4 minutes, P=0.056) was shorter in the GP patient group. Deviation from maintenance temperature (2.0% vs. 23.7%, P<0.001) occurred significantly more frequently in the WB group. The mean absolute temperature difference from 33℃ during the maintenance period was 0.19℃ (95% confidence interval [CI], 0.17℃ to 0.21℃) in the GP group and 0.76℃ (95% CI, 0.71℃ to 0.80℃) in the WB group. GP significantly decreased this difference by 0.59℃ (95% CI, 0.44℃ to 0.75℃; P<0.001).

Conclusions:

The GP was superior to the WB for strict temperature control during TTM.

Variability of extracorporeal cardiopulmonary resuscitation utilization for refractory adult out-of-hospital cardiac arrest: an international survey study

Objective

A growing interest in extracorporeal cardiopulmonary resuscitation (ECPR) as a rescue strategy for refractory adult out-of-hospital cardiac arrest (OHCA) currently exists. This study aims to determine current standards of care and practice variation for ECPR patients in the USA and Korea.

Methods

In December 2015, we surveyed centers from the Korean Hypothermia Network (KORHN) Investigators and the US National Post-Arrest Research Consortium (NPARC) on current targeted temperature management and ECPR practices. This project analyzes the subsection of questions addressing ECPR practices. We summarized survey.

Results

using descriptive statistics.

Results

Overall, 9 KORHN and 4 NPARC centers reported having ECPR programs and had complete survey data available. Two KORHN centers utilized extracorporeal membrane oxygenation only for postarrest circulatory support in patients with refractory shock and were excluded from further analysis. Centers with available ECPR generally saw a high volume of OHCA patients (10/11 centers care for &gt;75 OHCA a year). Location of, and providers trained for cannulation varied across centers. All centers in both countries (KORHN 7/7, NPARC 4/4) treated comatose ECPR patients with targeted temperature management. All NPARC centers and four of seven KORHN centers reported having a standardized hospital protocol for ECPR. Upper age cutoff for eligibility ranged from 60 to 75 years. No absolute contraindications were unanimous among centers.

Conclusion

A wide variability in practice patterns exist between centers performing ECPR for refractory OHCA in the US and Korea. Standardized protocols and shared research databases might inform best practices, improve outcomes, and provide a foundation for prospective studies.

Neurologic Recovery After Cardiac Arrest: a Multifaceted Puzzle Requiring Comprehensive Coordinated Care

OPINION STATEMENT

Surviving cardiac arrest (CA) requires a longitudinal approach with multiple levels of responsibility, including fostering a culture of action by increasing public awareness and training, optimization of resuscitation measures including frequent updates of guidelines and their timely implementation into practice, and optimization of post-CA care. This clearly goes beyond resuscitation and targeted temperature management. Brain-directed physiologic goals should dictate the post-CA management, as accumulating evidence suggests that the degree of hypoxic brain injury is the main determinant of survival, regardless of the etiology of arrest. Early assessment of the need for further hemodynamic and electrophysiologic cardiac interventions, adjusting ventilator settings to avoid hyperoxia/hypoxia while targeting high-normal to mildly elevated PaCO₂, maintaining mean arterial blood pressures >65 mmHg, evaluating for and treating seizures, maintaining euglycemia, and aggressively pursuing normothermia are key steps in reducing the bioenergetic failure that underlies secondary brain injury. Accurate neuroprognostication requires a multimodal approach with standardized assessments accounting for confounders while recognizing the importance of a delayed prognostication when there is any uncertainty regarding outcome. The concept of a highly specialized post-CA team with expertise in the management of post-CA syndrome (mindful of the brain-directed physiologic goals during the early post-resuscitation phase), TTM, and neuroprognostication, guiding the comprehensive care to the CA survivor, is likely cost-effective and should be explored by institutions that frequently care for these patients. Finally, providing tailored rehabilitation care with systematic reassessment of the needs and overall goals is key for increasing independence and improving quality-of-life in survivors, thereby also alleviating the burden on families. Emerging evidence from multicenter collaborations advances the field of resuscitation at an incredible pace, challenging previously well-established paradigms. There is no more room for "conventional wisdom" in saving the survivors of cardiac arrest.