Impact of Total Epinephrine Dose on Long Term Neurological Outcome for Cardiac Arrest Patients: A Cohort Study

Cumulative epinephrine dose during cardiac arrest and neurologic outcome after extracorporeal cardiopulmonary resuscitation

BACKGROUND

Epinephrine is recommended without an apparent ceiling dosage during cardiac arrest. However, excessive alpha- and beta-adrenergic stimulation may contribute to unnecessarily high aortic afterload, promote post-arrest myocardial dysfunction, and result in cerebral microvascular insufficiency in patients receiving extracorporeal cardiopulmonary resuscitation (ECPR).

METHODS

This was a retrospective cohort study of adults (≥ 18 years) who received ECPR at large academic ECMO center from 2018 to 2022. Patients were grouped based on the amount of epinephrine given during cardiac arrest into low (≤ 3 mg) and high (> 3 mg) groups. The primary endpoint was neurologic outcome at hospital discharge, defined by cerebral performance category (CPC). Multivariable logistic regression was used to assess the relationship between cumulative epinephrine dosage during arrest and neurologic outcome.

RESULTS

Among 51 included ECPR cases, the median age of patients was 60 years, and 55% were male. The mean cumulative epinephrine dose administered during arrest was 6.2 mg but ranged from 0 to 24 mg. There were 18 patients in the low-dose (≤ 3 mg) and 25 patients in the high-dose (> 3 mg) epinephrine groups. Favorable neurologic outcome at discharge was significantly greater in the low-dose (55%) compared to the high-dose (24%) group (p = 0.025). After adjusting for age, those who received higher doses of epinephrine during the arrest were more likely to have unfavorable neurologic outcomes at hospital discharge (odds ratio 4.6, 95% CI 1.3, 18.0, p = 0.017).

CONCLUSION

After adjusting for age, cumulative epinephrine doses above 3 mg during cardiac arrest may be associated with unfavorable neurologic outcomes after ECPR and require further investigation.

A model for predicting return of spontaneous circulation and neurological outcomes in adults after in-hospital cardiac arrest: development and evaluation

Introduction

In-hospital CA (IHCA) is associated with rates of high incidence, low return of spontaneous circulation (ROSC), low survival to discharge, and poor neurological outcomes. We aimed to construct and evaluate prediction models for non-return of spontaneous circulation (non-ROSC) and poor neurological outcomes 12 months after ROSC (PNO-12).

Methods

We retrospectively analyzed baseline and clinical data from patients experiencing cardiac arrest (CA) in a big academic hospital of Jilin University in China. Patients experiencing CA between September 1, 2019 and December 31, 2020 were categorized into the ROSC and non-ROSC groups. Patients maintaining ROSC >20 min were divided into the good and PNO-12 subgroups.

Results

Univariate and multivariate logistic regression identified independent factors associated with non-ROSC and PNO-12. Two nomogram prediction models were constructed and evaluated. Of 2,129 patients with IHCA, 851 were included in the study. Multivariate logistic regression analysis revealed that male sex, age >80 years, CPR duration >23 min, and total dose of adrenaline >3 mg were significant risk factors for non-ROSC. Before CA, combined arrhythmia, initial defibrillation rhythm, and advanced airway management (mainly as endotracheal intubation) also influenced outcomes. The area under the receiver operating characteristic curve in the prediction model was 0.904 (C-index: 0.901). Respiratory failure, shock, CA in the monitoring area, advanced airway management, and noradrenaline administration were independent risk factors for PNO-12. The AUC was 0.912 (C-index: 0.918).

Conclusions

Prediction models based on IHCA data could be helpful to reduce mortality rates and improve prognosis.

Epinephrine in Cardiac Arrest: Identifying a Potential Limit for Resuscitation

Introduction

Epinephrine continues to be a fundamental part of the Advanced Cardiac Life Support algorithm despite a lack of evidence that it improves neurologically intact survival. Our aim was both to identify a potential upper limit of epinephrine use in resuscitations and to demonstrate real-world epinephrine use in different patient subgroups.

Methods

This was a single-center, retrospective cohort study, conducted between August 1, 2016-July 1, 2021, of patients with medical cardiac arrest who were administered a known number of epinephrine doses. The primary outcome was neurologically intact discharge defined by a modified Rankin scale ≤3, with secondary outcomes of comparing epinephrine doses by age, rhythm, and emergency medical services vs emergency department administration of epinephrine.

Results

The study included 1,330 patients, with 184 patients (13.8%) surviving to neurologically intact discharge. The primary outcome of neurologically intact discharge was found in 89 (65.4%) patients in the zero epinephrine dose group, 75 (20.0%) in the 1-3 dose group, 15 (4.3%) in the 4-6 dose group, and one (0.002%) in the ≥7 dose group (P < 0.001). Patients received similar amounts of epinephrine when stratified by age, while patients with shockable rhythms received more epinephrine than patients with non-shockable rhythms.

Conclusion

There was a significant decrease in neurologically intact discharge with increasing number of epinephrine doses, and our data suggests that seven or more doses of epinephrine is almost always futile. While further prospective studies are needed, clinicians should consider epinephrine doses when weighing the futility or benefit of continued resuscitation efforts.

Epinephrine Dosing Use During Extracorporeal Cardiopulmonary Resuscitation: Single-Center Retrospective Cohort

OBJECTIVES

During pediatric cardiac arrest, contemporary guidelines recommend dosing epinephrine at regular intervals, including in patients requiring extracorporeal membrane oxygenation (ECMO). The impact of epinephrine-induced vasoconstriction on systemic afterload and venoarterial ECMO support is not well-defined.

DESIGN

Nested retrospective observational study within a single center. The primary exposure was time from last dose of epinephrine to initiation of ECMO flow; secondary exposures included cumulative epinephrine dose and arrest time. Systemic afterload was assessed by mean arterial pressure and use of systemic vasodilator therapy; ECMO pump flow and Vasoactive-Inotrope Score (VIS) were used as measures of ECMO support. Clearance of lactate was followed post-cannulation as a marker of systemic perfusion.

SETTING

PICU and cardiac ICU in a quaternary-care center.

PATIENTS

Patients 0-18 years old who required ECMO cannulation during resuscitation over the 6 years, 2014-2020. Patients were excluded if ECMO was initiated before cardiac arrest or if the resuscitation record was incomplete.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 92 events in 87 patients, with 69 events having complete data for analysis. The median (interquartile range) of total epinephrine dosing was 65 mcg/kg (37-101 mcg/kg), with the last dose given 6 minutes (2-16 min) before the initiation of ECMO flows. Shorter interval between last epinephrine dose and ECMO initiation was associated with increased use of vasodilators within 6 hours of ECMO ( p = 0.05), but not with mean arterial pressure after 1 hour of support (estimate, -0.34; p = 0.06). No other associations were identified between epinephrine delivery and mean arterial blood pressure, vasodilator use, pump speed, VIS, or lactate clearance.

CONCLUSIONS

There is limited evidence to support the idea that regular dosing of epinephrine during cardiac arrest is associated with increased in afterload after ECMO cannulation. Additional studies are needed to validate findings against ECMO flows and clinically relevant outcomes.

How Epinephrine Administration Interval Impacts the Outcomes of Resuscitation during Adult Cardiac Arrest: A Systematic Review and Meta-Analysis

Current guidelines for treating cardiac arrest recommend administering 1 mg of epinephrine every 3−5 min. However, this interval is based solely on expert opinion. We aimed to investigate the impact of the epinephrine administration interval (EAI) on resuscitation outcomes in adults with cardiac arrest. We systematically reviewed the PubMed, EMBASE, and Scopus databases. We included studies comparing different EAIs in adult cardiac arrest patients with reported neurological outcomes. Pooled estimates were calculated using the IVhet meta-analysis, and the heterogeneities were assessed using Q and I2 statistics. We evaluated the study risk of bias and overall quality using validated bias assessment tools. Three studies were included. All were classified as “good quality” studies. Only two reported the primary outcome. Compared with a recommended EAI of 3−5 min, a favorable neurological outcome was not significantly different in patients with the other frequencies: for <3 min, odds ratio (OR) 1.93 (95% CI: 0.82−4.54); for >5 min, OR 1.01 (95% CI: 0.55−1.87). For survival to hospital discharge, administering epinephrine for less than 3 min was not associated with a good outcome (OR 1.66, 95% CI: 0.89−3.10). Moreover, EAI of >5 min did not pose a benefit (OR 0.87, 95% CI: 0.68−1.11). Our review showed that EAI during CPR was not associated with better hospital outcomes. Further clinical trials are necessary to determine the optimal dosing interval for epinephrine in adults with cardiac arrest.

Analysis of Epinephrine Dose, Targeted Temperature Management, and Neurologic and Survival Outcomes Among Adults With Out-of-Hospital Cardiac Arrest

IMPORTANCE

Epinephrine improves return of spontaneous circulation after out-of-hospital cardiac arrest (OHCA). These beneficial cardiac effects do not directly translate to better neurologic outcomes, possibly because of epinephrine-induced microvascular effects that produce critical brain ischemia.

OBJECTIVE

To examine whether targeted temperature management (TTM) modifies the adverse association between increasing prehospital epinephrine dose and neurologically favorable survival.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study assessed 14 612 adults from Seattle and King County, Washington, with nontraumatic OHCA between January 1, 2008, and December 31, 2018, and included those who achieved return of spontaneous circulation and were unconscious at hospital admission. Data analysis was performed from April 2021 to May 2022.

EXPOSURES

Epinephrine dose and TTM during prehospital resuscitation.

MAIN OUTCOMES AND MEASURES

Favorable neurologic survival (Cerebral Performance Category [CPC] 1 or 2) and survival to hospital discharge.

RESULTS

Of the 14 612 assessed adults, 5253 (median age, 63 years; IQR, 51-74 years; 3460 [65.8%] male) were eligible for the study. The median epinephrine dose was 2.0 mg (IQR, 1.0-3.0 mg); 3052 patients (58.1%) received TTM. In all, 1889 patients (36.0%) survived with CPC 1 to 2, and 2177 (41.4%) survived to discharge. Increasing doses of epinephrine were associated with a decreasing likelihood of CPC 1 to 2 (odds ratio [OR], 0.46; 95% CI 0.42-0.50 for each additional milligram of epinephrine) and survival (OR, 0.47; 95% CI, 0.43-0.51). The dose-dependent epinephrine association was modified by TTM. After adjusting for Utstein covariates, TTM was associated with a relative stepwise improvement in odds of CPC 1 to 2 (interaction OR, 1.36; 95% CI, 1.22-1.51) and survival (interaction OR, 1.37; 95% CI, 1.24-1.51). A significant interaction was also observed when the analysis was stratified according to initial rhythm among shockable OHCA and nonshockable OHCA (shockable interaction OR, 1.20; 95% CI, 1.04-1.39; and nonshockable interaction OR, 1.24, 95% CI, 1.07-1.45).

CONCLUSIONS AND RELEVANCE

This cohort study found an interaction between TTM and epinephrine dose such that the beneficial association of TTM increased with increasing epinephrine dose, suggesting that TTM may attenuate the adverse effects of higher-dose epinephrine.

Targeted Delivery of Electrical Shocks and Epinephrine, Guided by Ventricular Fibrillation Amplitude Spectral Area, Reduces Electrical and Adrenergic Myocardial Burden, Improving Survival in Swine

Background

We previously reported that resuscitation delivering electrical shocks guided by real‐time ventricular fibrillation amplitude spectral area (AMSA) enabled return of spontaneous circulation (ROSC) with fewer shocks, resulting in less myocardial dysfunction. We now hypothesized that AMSA could also guide delivery of epinephrine, expecting further outcome improvement consequent to less electrical and adrenergic burdens.

Methods and Results

A swine model of ventricular fibrillation was used to compare after 10 minutes of untreated ventricular fibrillation a guidelines‐driven (n=8) resuscitation protocol, delivering shocks every 2 minutes and epinephrine every 4 minutes, with an AMSA‐driven shocks (n=8) protocol, delivering epinephrine every 4 minutes, and with an AMSA‐driven shocks and epinephrine (ADSE; n=8) protocol. For guidelines‐driven, AMSA‐driven shocks, and ADSE protocols, the time to ROSC (mean±SD) was 569±164, 410±111, and 400±80 seconds (P=0.045); the number of shocks (mean±SD) was 5±2, 3±1, and 3±2 (P=0.024) with ADSE fewer than guidelines‐driven (P=0.03); and the doses of epinephrine (median [interquartile range]) were 2.0 (1.3–3.0), 1.0 (1.0–2.8), and 1.0 (0.3–3.0) (P=0.419). The ROSC rate was similar, yet survival after ROSC favored AMSA‐driven protocols (guidelines‐driven, 3/6; AMSA‐driven shocks, 6/6; and ADSE, 7/7; P=0.019 by log‐rank test). Left ventricular function and survival after ROSC correlated inversely with electrical burden (ie, cumulative unsuccessful shocks, J/kg; P=0.020 and P=0.046) and adrenergic burden (ie, total epinephrine doses, mg/kg; P=0.042 and P=0.002).

Conclusions

Despite similar ROSC rates achieved with all 3 protocols, AMSA‐driven shocks and ADSE resulted in less postresuscitation myocardial dysfunction and better survival, attributed to attaining ROSC with less electrical and adrenergic myocardial burdens.