The time dependent association of adrenaline administration and survival from out-of-hospital cardiac arrest

Intraosseous and Intravenous Epinephrine Administration Routes in Out-of-Hospital Cardiac Arrest: Survival and Neurologic Outcomes

BACKGROUND

The rate of survival after out-of-hospital cardiac arrest varies depending on the timeliness and effectiveness of prehospital interventions. This study was conducted to compare out-of-hospital cardiac arrest outcomes between intravenous and intraosseous routes and between upper and lower extremity routes for drug administration.

METHODS AND RESULTS

We retrospectively analyzed data (collected using the Utstein template) from 1220 patients who had experienced out-of-hospital cardiac arrest in Taiwan's Taoyuan City between January 2021 and August 2023. The patients were stratified into intravenous and intraosseous groups by treatment approach and upper and lower extremity access groups by access site. The study outcomes were survival to discharge, favorable neurologic outcomes (Cerebral Performance Category score 1 or 2), and survival for >2 hours. The study groups were statistically compared before and after propensity score matching. Significant pre-propensity score matching differences were observed between intravenous and intraosseous groups, and the aforementioned study outcomes were better in the intravenous group than in the intraosseous group. However, the between-group differences became nonsignificant after propensity score matching. Furthermore, lower extremity access and delayed epinephrine administration were associated with worse outcomes. Survival rates fell below 12.6% when time to treatment exceeded 15 minutes, particularly in the cases of intraosseous access and lower extremity access.

CONCLUSIONS

This study highlights the benefits of early intervention and upper extremity access for drug administration in patients with out-of-hospital cardiac arrest. Intraosseous access may serve as a viable alternative to intravenous access. Timely administration of essential drugs during resuscitation can improve clinical outcomes and thus has implications for emergency medical service training.

The Route to ROSC: Evaluating the Impact of Route and Timing of Epinephrine Administration in Out-of-Hospital Cardiac Arrest Outcomes

OBJECTIVES

Previous investigations comparing intraosseous (IO) and intravenous (IV) epinephrine delivery in out-of-hospital cardiac arrest (OHCA) suggest that epinephrine is oftentimes more expeditiously administered via the IO route, but this temporal benefit doesn't always translate to clinical benefit. However, very few studies adequately controlled for indication and resuscitation time biases, making the influence of first epinephrine route on OHCA outcomes unclear. To determine the association between first epinephrine route and return of spontaneous circulation (ROSC) while controlling for resuscitation time bias and other potential confounders.

METHODS

We conducted a retrospective analysis using the 2020 ESO Data Collaborative dataset. Adult patients with a witnessed, non-traumatic OHCA prior to EMS arrival were included. Logistic regression was used to determine the association between medication route and ROSC. Linear regression was then used to calculate the probability of ROSC for each route across all call receipt-to-drug delivery intervals. Using these linear equations, the call receipt-to-drug delivery intervals were calculated that would yield equivalent probabilities of ROSC between the IV and IO routes.

RESULTS

Data were available for 10,350 patients, of which 27.4% presented with a shockable rhythm, 29.7% received bystander CPR, and 39.6% experienced ROSC. After controlling for confounders, IO epinephrine was associated with decreased likelihood of ROSC (OR = 0.77, p < 0.001). The linear regression models provided differing slope coefficients for ROSC between each route, with the IV route associated with a higher likelihood of ROSC for any given call receipt-to-drug-delivery interval. From these equations, the additional time allowed to establish an IV and administer epinephrine intravenously beyond the time required for IO delivery, yet with an equivalent predicted probability of ROSC via the IO route, was calculated. This additional time interval for intravenous administration declined linearly from 9 min at a call receipt-to-intraosseous epinephrine interval of 4 min to no additional time at a call receipt-to-intraosseous epinephrine interval of 29 min.

CONCLUSIONS

This retrospective analysis of a national EMS database revealed that IO epinephrine was negatively associated with ROSC. Additionally, there appears to be a finite time window during which intravenous epinephrine remains superior to the intraosseous route even if there are brief initial delays in IV drug delivery.

Early intramuscular adrenaline administration is associated with improved survival from out-of-hospital cardiac arrest

BACKGROUND

Early administration of adrenaline is associated with improved survival after out-of-hospital cardiac arrest (OHCA). Delays in vascular access may impact the timely delivery of adrenaline. Novel methods for administering adrenaline before vascular access may enhance survival. The objective of this study was to determine whether an initial intramuscular (IM) adrenaline dose followed by standard IV/IO adrenaline is associated with improved survival after OHCA.

METHODS STUDY DESIGN

We conducted a before-and-after study of the implementation of an early, first-dose IM adrenaline EMS protocol for adult OHCAs. The pre-intervention period took place between January 2010 and October 2019. The post-intervention period was between November 2019 and May 2024.

SETTING

Single-center urban, two-tiered EMS agency.

PARTICIPANTS

Adult, nontraumatic OHCA meeting criteria for adrenaline use.

INTERVENTION

Single dose (5 mg) IM adrenaline. All other care, including subsequent IV or IO adrenaline, followed international guidelines.

MAIN OUTCOMES AND MEASURES

The primary outcome was survival to hospital discharge. Secondary outcomes were time from EMS arrival to the first dose of adrenaline, survival to hospital admission, and favorable neurologic function at discharge.

RESULTS

Among 1405 OHCAs, 420 (29.9%) received IM adrenaline and 985 (70.1%) received usual care. Fifty-two patients received the first dose of adrenaline through the IV or IO route within the post-intervention period and were included in the standard care group analysis. Age was younger and bystander CPR was higher in the IM adrenaline group. All other characteristics were similar between IM and standard care cohorts. Time to adrenaline administration was faster for the IM cohort [(median 4.3 min (IQR 3.0-6.0) vs. 7.8 min (IQR 5.8-10.4)]. Compared with standard care, IM adrenaline was associated with improved survival to hospital admission (37.1% vs. 31.6%; aOR 1.37, 95% CI 1.06-1.77), hospital survival (11.0% vs 7.0%; aOR 1.73, 95% CI 1.10-2.71) and favorable neurologic status at hospital discharge (9.8% vs 6.2%; aOR 1.72, 95% CI 1.07-2.76).

CONCLUSION

In this single-center before-and-after implementation study, an initial IM dose of adrenaline as an adjunct to standard care was associated with improved survival to hospital admission, survival to hospital discharge, and functional survival. A randomized controlled trial is needed to fully assess the potential benefit of IM adrenaline delivery in OHCA.

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.

Impact of intravenous accessibility and prehospital epinephrine use on survival outcomes of adult nontraumatic out-of-hospital cardiac arrest patients

BACKGROUND

This study compared out-of-hospital cardiac arrest (OHCA) patient outcomes based on intravenous (IV) access and prehospital epinephrine use.

METHODS

A retrospective study in Ulsan, South Korea, from January 2017 to December 2022, analyzed adult nontraumatic OHCA cases. Patients were grouped: Group 1 (no IV attempts), Group 2 (failed IV access), Group 3 (successful IV access without epinephrine), and Group 4 (successful IV access with epinephrine), with comparisons using logistic regression analysis.

RESULTS

Among 2,656 patients, Group 4 had significantly lower survival to hospital discharge (adjusted OR 0.520, 95% CI 0.346-0.782, p = 0.002) and favorable neurological outcomes (adjusted OR 0.292, 95% CI 0.140-0.611, p = 0.001) than Group 1. Groups 2 and 3 showed insignificant survival to hospital discharge (adjusted OR 0.814, 95% CI 0.566-1.171, p = 0.268) and (adjusted OR 1.069, 95% CI 0.810-1.412, p = 0.636) and favorable neurological outcomes (adjusted OR 0.585, 95% CI 0.299-1.144, p = 0.117) and (adjusted OR 1.075, 95% CI 0.689-1.677, p = 0.751). In the shockable rhythm group, Group 3 had better survival to hospital discharge (adjusted OR 1.700, 95% CI 1.044-2.770, p = 0.033).

CONCLUSIONS

Successful IV access with epinephrine showed worse outcomes in both rhythm groups than no IV attempts. Outcomes for failed IV and successful IV access without epinephrine were inconclusive. Importantly, successful IV access without epinephrine showed favorable survival to hospital discharge in the shockable rhythm group, warranting further research into IV access for fluid resuscitation in shockable rhythm OHCA patients.

Effects of physician-present prehospital care in patients with out-of-hospital cardiac arrest on return of spontaneous circulation: A retrospective, observational study in Saga, Japan

Background and Aims

Emergency medical services for out-of-hospital cardiac arrest (OHCA) vary according to region and country, and patient prognosis differs accordingly. In Japan, physicians may provide prehospital care. However, the effect of physician-present prehospital care on achieving return of spontaneous circulation (ROSC) in patients with cardiac arrest is not clear. Here, we aimed to examine the effect of physician-present prehospital care on the prognosis of patients with OHCA at our hospital compared with physician-absent care.

Methods

In this retrospective, observational study, patients aged ≥18 years with non-traumatic OHCA from a single center in Saga City, Japan, between April 2011 and December 2019, were included. Patients were divided into two groups, based on prehospital physician presence or absence. Logistic regression analysis was used to determine the association between physician-present prehospital care and ROSC.

Results

Of 820 patients with OHCA, 151 had a physician present and 669 did not. Logistic regression analysis with no adjustment showed that the odds ratio (OR) of physician-present prehospital care for an increased ROSC rate was 1.74 (95% confidence interval [CI]: 1.22-2.48, p = 0.002). Logistic-regression analysis adjusted for ROSC-related factors indicated an OR of 1.05 (95% CI: 0.47-2.34, p = 0.914) for physician-present prehospital care to ROSC.

Conclusion

Physician-present prehospital care may not necessarily lead to increased ROSC rates. However, insufficient data limited our study findings. Further studies involving larger sample sizes are warranted.

Association between prehospital advanced life support by emergency medical services personnel and neurological outcomes among adult out-of-hospital cardiac arrest patients treated with extracorporeal cardiopulmonary resuscitation: A secondary analysis of the SAVE-J II study

Study Objective

Early deployment of extracorporeal cardiopulmonary resuscitation (ECPR) is critical in treating refractory out-of-hospital cardiac arrest (OHCA) patients who are potential candidates for ECPR. The effect of prehospital advanced life support (ALS), including epinephrine administration or advanced airway, compared with no ALS in this setting remains unclear. This study's objective was to determine the association between any prehospital ALS care and outcomes of patients who received ECPR with emergency medical services-treated OHCA.

Methods

This was a secondary analysis of data from the Study of Advanced Cardiac Life Support for Ventricular Fibrillation with Extracorporeal Circulation in Japan (SAVE-J) II study. Patients were separated into 2 groups-those who received prehospital ALS (ALS group) and those did not receive prehospital ALS (no ALS group). Multiple logistic regression analysis was used to investigate the association between prehospital ALS and favorable neurological outcomes (defined as Cerebral Performance Category scores 1-2) at hospital discharge.

Results

A total of 1289 patients were included, with 644 patients in the ALS group and 645 patients in the no ALS group. There were fewer favorable neurological outcomes at hospital discharge in the ALS group compared with the no ALS group (10.4 vs 19.8%, p <0.001). A multiple logistic regression analysis revealed that any prehospital ALS care (adjusted odds ratios 0.47; 95% confidence interval 0.34-0.66; p <0.001) was associated with unfavorable neurological outcomes at hospital discharge.

Conclusion

Prehospital ALS was associated with worse neurological outcomes at hospital discharge in patients treated with ECPR for OHCA. Further prospective studies are required to determine the clinical implications of these findings.

Delayed administration of epinephrine is associated with worse neurological outcomes in patients with out-of-hospital cardiac arrest and initial pulseless electrical activity: insight from the nationwide multicentre observational JAAM-OHCA (Japan Association for Acute Medicine) registry

Aims

The delayed administration of epinephrine has been proven to worsen the neurological outcomes of patients with out-of-hospital cardiac arrest (OHCA) and shockable rhythm or asystole. We aimed to investigate whether the delayed administration of epinephrine might also worsen the neurological outcomes of patients with witnessed OHCA and initial pulseless electrical activity (PEA).

Methods and results

The JAAM-OHCA Registry is a multicentre registry including OHCA patients between 2014 and 2017. Patients with emergency medical services (EMS)-treated OHCA and initial PEA rhythm were included. The primary exposure was the time from the EMS call to the administration of epinephrine. The secondary exposure was the time to epinephrine dichotomized as early (≤15 min) or delayed (>15 min). The primary outcome was the achievement of a favourable neurological outcome, defined as Cerebral Performance Categories Scale 1–2 at 30 days after OHCA. Out of 34 754 patients with OHCA, 3050 patients were included in the present study. After adjusting for potential confounders, the delayed administration of the epinephrine was associated with a lower likelihood of achieving a favourable neurological outcome [adjusted odds ratio (OR) 0.96; 95% confidence interval (CI) 0.93–0.99; P = 0.016]. The percentage of patients who achieved a favourable neurological outcome in the delayed epinephrine group was lower than that in the early epinephrine group (1.3% vs. 4.7%; adjusted OR 0.33; 95% CI 0.15–0.72; P = 0.005). A restricted cubic spline analysis demonstrated that delayed epinephrine administration could decrease the likelihood of achieving a favourable neurological outcome; this was significant within the first 10 min.

Conclusions

The delayed administration of epinephrine was associated with worse neurological outcomes in patients with witnessed OHCA patients with initial PEA.

[ERC guidelines 2021 on cardiopulmonary resuscitation]

The current European guidelines on cardiopulmonary resuscitation were published in 2021. The guidelines, which are structured in 12 chapters, were supplemented with the chapters on epidemiology and life-saving systems. In the following article, the recommendations on basic life support, advanced measures for resuscitation in adults and postresuscitation treatment are discussed.

Timing of Intravenous Epinephrine Administration During Out-of-Hospital Cardiac Arrest

BACKGROUND

Current guidelines for cardiopulmonary resuscitation recommend that standard dose of epinephrine be administered every 3 to 5 min during cardiac arrest. However, there is controversy about the association between timing of epinephrine administration and outcomes after out-of-hospital cardiac arrest (OHCA). This study aimed to determine whether the timing of intravenous epinephrine administration is associated with outcomes after OHCA.

METHODS

We analyzed Japanese government-led nationwide population-based registry data for OHCA. Adult OHCA patients who received intravenous epinephrine by emergency medical service personnel in the prehospital setting from 2011 to 2017 were included. Multivariable logistic regression models were used to assess the associations between time to first epinephrine administration and outcomes after OHCA. Subsequently, associations between early (≤20 min) versus delayed (>20 min) epinephrine administration and outcomes after OHCA were examined using propensity score-matched analyses. The primary outcome was 1-month neurologically favorable survival.

RESULTS

A total of 119,946 patients (mean [SD] age, 75.2 [14.8] years; 61.4% male) were included. The median time to epinephrine was 23 min (interquartile range, 19-29). Longer time to epinephrine was significantly associated with a decreased chance of 1-month neurologically favorable survival (multivariable adjusted OR per minute delay, 0.91 [95% CI, 0.90-0.92]). In the propensity score-matched cohort, when compared with early (≤20 min) epinephrine, delayed (>20 min) epinephrine was associated with a decreased chance of 1-month neurologically favorable survival (959/42,804 [2.2%] vs. 330/42,804 [0.8%]; RR, 0.34; 95% CI, 0.30-0.39; NNT, 69).

CONCLUSIONS

Delay in epinephrine administration was associated with a decreased chance of 1-month neurologically favorable survival among patients with OHCA.

Intramuscular adrenaline for out-of-hospital cardiac arrest is associated with faster drug delivery: A feasibility study

BACKGROUND

Early adrenaline administration is associated with return of spontaneous circulation (ROSC) and survival in out-of-hospital cardiac arrest (OHCA). Animal data demonstrate a similar rate of ROSC when early intramuscular (IM) adrenaline is given compared to early intravenous (IV) adrenaline.

AIM

To evaluate the feasibility of protocolized first-dose IM adrenaline in OHCA and it's effect on time from Public Safety Access Point (PSAP) call receipt to adrenaline administration when compared to IO and IV administration.

METHODS

This is a before-and-after feasibility study of adult OHCAs in a single EMS service following adoption of a protocol for first-dose IM adrenaline. Time from PSAP call to administration and outcomes were compared to 674 historical controls (from January 1, 2013-February 8, 2021) who received at least one dose of adrenaline by IV or IO routes.

RESULTS

During the study period, first-dose IM adrenaline was administered to 99 patients (December 1, 2019-February 8, 2021). IM adrenaline was given a median of 12.2 min (95% CI 11.4-13.1 min) after the PSAP call receipt compared to 15.3 min for the IV route (95% CI 14.6-16.0 min) and 15.3 min for the IO route (95% CI 14.9-15.7 min) with a time savings of 3 min (95% CI 2-4 min). Rates of survival to hospital discharge appeared similar between groups: 10% for IM, 8% for IV and 7% for IO. However, results related to survival were underpowered for statistical comparison.

CONCLUSIONS

Within the limitations of a small sample size and before-and-after design, first-dose IM adrenaline was feasible and reduced the time to adrenaline administration.

Adrenaline to improve survival in out-of-hospital cardiac arrest: the PARAMEDIC2 RCT

BACKGROUND

Adrenaline has been used as a treatment for cardiac arrest for many years, despite uncertainty about its effects on long-term outcomes and concerns that it may cause worse neurological outcomes.

OBJECTIVES

The objectives were to evaluate the effects of adrenaline on survival and neurological outcomes, and to assess the cost-effectiveness of adrenaline use.

DESIGN

This was a pragmatic, randomised, allocation-concealed, placebo-controlled, parallel-group superiority trial and economic evaluation. Costs are expressed in Great British pounds and reported in 2016/17 prices.

SETTING

This trial was set in five NHS ambulance services in England and Wales.

PARTICIPANTS

Adults treated for an out-of-hospital cardiac arrest were included. Patients were ineligible if they were pregnant, if they were aged < 16 years, if the cardiac arrest had been caused by anaphylaxis or life-threatening asthma, or if adrenaline had already been given.

INTERVENTIONS

Participants were randomised to either adrenaline (1 mg) or placebo in a 1 : 1 allocation ratio by the opening of allocation-concealed treatment packs.

MAIN OUTCOME MEASURES

The primary outcome was survival to 30 days. The secondary outcomes were survival to hospital admission, survival to hospital discharge, survival at 3, 6 and 12 months, neurological outcomes and health-related quality of life through to 6 months. The economic evaluation assessed the incremental cost per quality-adjusted life-year gained from the perspective of the NHS and Personal Social Services. Participants, clinical teams and those assessing patient outcomes were masked to the treatment allocation.

RESULTS

From December 2014 to October 2017, 8014 participants were assigned to the adrenaline (n = 4015) or to the placebo (n = 3999) arm. At 30 days, 130 out of 4012 participants (3.2%) in the adrenaline arm and 94 out of 3995 (2.4%) in the placebo arm were alive (adjusted odds ratio for survival 1.47, 95% confidence interval 1.09 to 1.97). For secondary outcomes, survival to hospital admission was higher for those receiving adrenaline than for those receiving placebo (23.6% vs. 8.0%; adjusted odds ratio 3.83, 95% confidence interval 3.30 to 4.43). The rate of favourable neurological outcome at hospital discharge was not significantly different between the arms (2.2% vs. 1.9%; adjusted odds ratio 1.19, 95% confidence interval 0.85 to 1.68). The pattern of improved survival but no significant improvement in neurological outcomes continued through to 6 months. By 12 months, survival in the adrenaline arm was 2.7%, compared with 2.0% in the placebo arm (adjusted odds ratio 1.38, 95% confidence interval 1.00 to 1.92). An adjusted subgroup analysis did not identify significant interactions. The incremental cost-effectiveness ratio for adrenaline was estimated at £1,693,003 per quality-adjusted life-year gained over the first 6 months after the cardiac arrest event and £81,070 per quality-adjusted life-year gained over the lifetime of survivors. Additional economic analyses estimated incremental cost-effectiveness ratios for adrenaline at £982,880 per percentage point increase in overall survival and £377,232 per percentage point increase in neurological outcomes over the first 6 months after the cardiac arrest.

LIMITATIONS

The estimate for survival with a favourable neurological outcome is imprecise because of the small numbers of patients surviving with a good outcome.

CONCLUSIONS

Adrenaline improved long-term survival, but there was no evidence that it significantly improved neurological outcomes. The incremental cost-effectiveness ratio per quality-adjusted life-year exceeds the threshold of £20,000-30,000 per quality-adjusted life-year usually supported by the NHS.

FUTURE WORK

Further research is required to better understand patients' preferences in relation to survival and neurological outcomes after out-of-hospital cardiac arrest and to aid interpretation of the trial findings from a patient and public perspective.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN73485024 and EudraCT 2014-000792-11.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 25. See the NIHR Journals Library website for further project information.

Intraosseous versus intravenous vascular access during cardiopulmonary resuscitation for out-of-hospital cardiac arrest: a systematic review and meta-analysis of observational studies

INTRODUCTION

This study is aimed to investigate the association of intraosseous (IO) versus intravenous (IV) route during cardiopulmonary resuscitation (CPR) with outcomes after out-of-hospital cardiac arrest (OHCA).

METHODS

We systematically searched PubMed, Embase, Cochrane Library and Web of Science from the database inception through April 2020. Our search strings included designed keywords for two concepts, i.e. vascular access and cardiac arrest. There were no limitations implemented in the search strategy. We selected studies comparing IO versus IV access in neurological or survival outcomes after OHCA. Favourable neurological outcome at hospital discharge was pre-specified as the primary outcome. We pooled the effect estimates in random-effects models and quantified the heterogeneity by the I² statistics. Time to intervention, defined as time interval from call for emergency medical services to establishing vascular access or administering medications, was hypothesized to be a potential outcome moderator and examined in subgroup analysis with meta-regression.

RESULTS

Nine retrospective observational studies involving 111,746 adult OHCA patients were included. Most studies were rated as high quality according to Newcastle-Ottawa Scale. The pooled results demonstrated no significant association between types of vascular access and the primary outcome (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.27-1.33; I², 95%). In subgroup analysis, time to intervention was noted to be positively associated with the pooled OR of achieving the primary outcome (OR: 3.95, 95% CI, 1.42-11.02, p: 0.02). That is, when the studies not accounting for the variable of "time to intervention" in the statistical analysis were pooled together, the meta-analytic results between IO access and favourable outcomes would be biased toward inverse association. No obvious publication bias was detected by the funnel plot.

CONCLUSIONS

The meta-analysis revealed no significant association between types of vascular access and neurological outcomes at hospital discharge among OHCA patients. Time to intervention was identified to be an important outcome moderator in this meta-analysis of observation studies. These results call for the need for future clinical trials to investigate the unbiased effect of IO use on OHCA CPR.

Epinephrine administration for adult out-of-hospital cardiac arrest patients with refractory shockable rhythm: time-dependent propensity score-sequential matching analysis from a nationwide population-based registry

BACKGROUND

Little is known about the effect of prehospital epinephrine administration in out-of-hospital cardiac arrest (OHCA) patients with refractory shockable rhythm, for whom initial defibrillation was unsuccessful.

METHODS

This study using Japanese nationwide population-based registry included all adult OHCA patients aged ≥18 years with refractory shockable rhythm between January 2014 and December 2017. Patients with or without epinephrine during cardiac arrest were sequentially matched using a risk set matching based on the time-dependent propensity scores within the same minute. The primary outcome was 1-month survival. The secondary outcomes included 1-month survival with favourable neurological outcome (cerebral performance category scale: 1 or 2) and prehospital return of spontaneous circulation (ROSC).

RESULTS

Of the 499,944 patients registered in the database during the study period, 22,877 were included. Among them, 8,467 (37.0%) received epinephrine. After time-dependent propensity score-sequential matching, 16,798 patients were included in the matched cohort. In the matched cohort, positive associations were observed between epinephrine and 1-month survival (epinephrine: 17.3% [1,454/8,399] vs. no epinephrine: 14.6% [1,224/8,399]; RR 1.22 [95% confidence interval {CI}, 1.13-1.32]) and prehospital ROSC (epinephrine: 22.2% [1,868/8,399] vs. no epinephrine: 10.7% [900/8399]; RR, 2.07 [95% CI, 1.91-2.25]). No significant positive association was observed between epinephrine and favourable neurological outcome (epinephrine: 7.8% [654/8,399] vs. no epinephrine: 7.1% [611/8,399]; RR, 1.13 [95% CI, 0.998-1.27]).

CONCLUSIONS

Using the nationwide population-based registry with time-dependent propensity score-sequential matching analysis, prehospital epinephrine administration in adult OHCA patients with refractory shockable rhythm was positively associated with 1-month survival and prehospital ROSC.

Effect of citywide enhancement of the chain of survival on good neurologic outcomes after out-of-hospital cardiac arrest from 2008 to 2017

Improving outcomes after out-of-hospital cardiac arrests (OHCAs) requires an integrated approach by strengthening the chain of survival and emergency care systems. This study aimed to identify the change in outcomes over a decade and effect of citywide intervention on good neurologic outcomes after OHCAs in Daegu. This is a before- and after-intervention study to examine the association between the citywide intervention to improve the chain of survival and outcomes after OHCA. The primary outcome was a good neurologic outcome, defined as a cerebral performance category score of 1 or 2. After dividing into 3 phases according to the citywide intervention, the trends in outcomes after OHCA by primary electrocardiogram rhythm were assessed. Logistic regression analysis was used to analyze the association between the phases and outcomes. Overall, 6203 patients with OHCA were eligible. For 10 years (2008–2017), the rate of survival to discharge and the good neurologic outcomes increased from 2.6% to 8.7% and from 1.5% to 6.6%, respectively. Especially for patients with an initial shockable rhythm, these changes in outcomes were more pronounced (survival to discharge: 23.3% in 2008 to 55.0% in 2017, good neurologic outcomes: 13.3% to 46.0%). Compared with phase 1, the adjusted odds ratio (AOR) and 95% confidence intervals (CI) for good neurologic outcomes was 1.20 (95% CI: 0.78–1.85) for phase 2 and 1.64 (1.09–2.46) for phase 3. For patients with an initial shockable rhythm, the AOR for good neurologic outcomes was 3.76 (1.88–7.52) for phase 2 and 5.51 (2.77–10.98) for phase 3. Citywide improvement was observed in the good neurologic outcomes after OHCAs of medical origin, and the citywide intervention was significantly associated with better outcomes, particularly in those with initial shockable rhythm.

Updates in Cardiac Arrest Resuscitation

There are approximately 350,000 out-of-hospital cardiac arrests and 200,000 in-hospital cardiac arrests annually in the United States, with survival rates of approximately 5% to 10% and 24%, respectively. The critical factors that have an impact on cardiac arrest survival include prompt recognition and activation of prehospital care, early cardiopulmonary resuscitation, and rapid defibrillation. Advanced life support protocols are continually refined to optimize intracardiac arrest management and improve survival with favorable neurologic outcome. This article focuses on current treatment recommendations for adult nontraumatic cardiac arrest, with emphasis on the latest evidence and controversies regarding intracardiac arrest management.

Early Administration of Adrenaline for Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

Background

The use of adrenaline in out‐of‐hospital cardiac arrest (OHCA) patients is still controversial. This study aimed to determine the effects of early pre‐hospital adrenaline administration in OHCA patients.

Methods and Results

PubMed, EMBASE, Google Scholar, and the Cochrane Library database were searched from study inception to February 2019 to identify studies that reported OHCA patients who received adrenaline. The primary outcome was survival to discharge, and the secondary outcomes were return of spontaneous circulation, favorable neurological outcome, and survival to hospital admission. A total of 574 392 patients were included from 24 studies. The use of early pre‐hospital adrenaline administration in OHCA patients was associated with a significant increase in survival to discharge (risk ratio [RR], 1.62; 95% CI, 1.45–1.83; P<0.001) and return of spontaneous circulation (RR, 1.50; 95% CI, 1.36–1.67; P<0.001), as well as a favorable neurological outcome (RR, 2.09; 95% CI, 1.73–2.52; P<0.001). Patients with shockable rhythm cardiac arrest had a significantly higher rate of survival to discharge (RR, 5.86; 95% CI, 4.25–8.07; P<0.001) and more favorable neurological outcomes (RR, 5.10; 95% CI, 2.90–8.97; P<0.001) than non‐shockable rhythm cardiac arrest patients.

Conclusions

Early pre‐hospital administration of adrenaline to OHCA patients might increase the survival to discharge, return of spontaneous circulation, and favorable neurological outcomes.

Registration

URL: https://www.crd.york.ac.uk/PROSPERO; Unique identifier: CRD42019130542.

Delays in Cardiopulmonary Resuscitation, Defibrillation, and Epinephrine Administration All Decrease Survival in In-hospital Cardiac Arrest

WHAT WE ALREADY KNOW ABOUT THIS TOPIC

Rapid response to witnessed, pulseless cardiac arrest is associated with increased survival.

WHAT THIS ARTICLE TELLS US THAT IS NEW

Assessment of witnessed, pulseless cardiac arrests occurring at 538 hospitals during a 9-yr period indicates that CPR did not occur immediately at 0 min in 5.7% of patients despite guidelines for instantaneous initiation. Delay in initiation of CPR was associated with significantly decreased survival.Time to initiation of CPR and subsequent time to initiation of administration of defibrillation shock (for shockable arrhythmias) and epinephrine were both associated with reduced patient survival.

BACKGROUND

Because the extent to which delays in initiating cardiopulmonary resuscitation (CPR) versus the time from CPR to defibrillation or epinephrine treatment affects survival remains unknown, it was hypothesized that all three independently decrease survival in in-hospital cardiac arrest.

METHODS

Witnessed, index cases of cardiac arrest from the Get With The Guidelines-Resuscitation Database occurring between 2000 and 2008 in 538 hospitals were included in this analysis. Multivariable risk-adjusted logistic regression examined the association of time to initiation of CPR and time from CPR to either epinephrine treatment or defibrillation with survival to discharge.

RESULTS

In the overall cohort of 57,312 patients, there were 9,802 survivors (17.1%). Times to initiation of CPR greater than 2 min were associated with a survival of 14.7% (91 of 618) as compared with 17.1% (9,711 of 56,694) if CPR was begun in 2 min or less (adjusted odds ratio [95% CI], 0.68 [0.54 to 0.87]; P < 0.002). Times from CPR to either defibrillation or epinephrine treatment of 2 min or less were associated with a survival of 18.0% (7,654 of 42,475), as compared with 15.0% (1,680 of 11,227) for 3 to 5 min (reference, 0 to 2 min; adjusted odds ratios [95% CI], 0.83 [0.78 to 0.88]; P < 0.001), 12.8% (382 of 2,983) for 6 to 8 min (0.67 [0.60 to 0.76], P < 0.001), and 13.7% (86 of 627) for 9 to 11 min (0.54 [0.42 to 0.69], P < 0.001).

CONCLUSIONS

Delays in the initiation of CPR and from CPR to defibrillation or epinephrine treatment were each associated with lower survival.

The influence of time to adrenaline administration in the Paramedic 2 randomised controlled trial

PURPOSE

To examine the time to drug administration in patients with a witnessed cardiac arrest enrolled in the Pre-Hospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug Administration in Cardiac Arrest (PARAMEDIC2) randomised controlled trial.

METHODS

The PARAMEDIC2 trial was undertaken across 5 NHS ambulance services in England and Wales with randomisation between December 2014 and October 2017. Patients with an out-of-hospital cardiac arrest who were unresponsive to initial resuscitation attempts were randomly assigned to 1 mg intravenous adrenaline or matching placebo according to treatment packs that were identical apart from treatment number. Participants and study staff were masked to treatment allocation.

RESULTS

8016 patients were enrolled, 4902 sustained a witnessed cardiac arrest of whom 2437 received placebo and 2465 received adrenaline. The odds of return of spontaneous circulation decreased in both groups over time but at a greater rate in the placebo arm odds ratio (OR) 0.93 (95% CI 0.92-0.95) compared with the adrenaline arm OR 0.96 (95% CI 0.95-0.97); interaction OR: 1.03, 95% CI 1.01-1.05, p = 0.005. By contrast, although the rate of survival and favourable neurological outcome decreased as time to treatment increased, the rates did not differ between the adrenaline and placebo groups.

CONCLUSION

The rate of return of spontaneous circulation, survival and favourable neurological outcomes decrease over time. As time to drug treatment increases, adrenaline increases the chances of return of spontaneous circulation. Longer term outcomes were not affected by the time to adrenaline administration. (ISRCTN73485024).

Benefits of adding a physician-staffed ambulance to bystander-witnessed out-of-hospital cardiac arrest: a community-based, observational study in Niigata, Japan

OBJECTIVE

This study aimed to assess the benefits of adding a physician-staffed ambulance to bystander-witnessed out-of-hospital cardiac arrest using a community-based registry.

DESIGN

Population-based, retrospective cohort study.

SETTING

An urban city with approximately 800 000 residents.

PARTICIPANTS

Patients aged ≥18 years with bystander-witnessed out-of-hospital cardiac arrests of medical aetiology in Niigata City, Japan, between January 2012 and December 2016, according to the Utstein style.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was 1-month survival with a favourable neurological outcome, defined as a cerebral performance category score of 1 or 2. We used logistic regression analysis to assess the association between favourable neurological outcome and prehospital physician involvement.

RESULTS

During the study period, a total of 4172 cardiac arrests were registered; of these, 892 patients with out-of-hospital cardiac arrest were eligible for this analysis, among whom 135 (15.1%) had prehospital physician involvement and 757 (84.9%) did not have prehospital physician involvement. The percentage of favourable neurological outcomes was 20.7% (28 of 135) in those with physician involvement and 10.4% (79 of 757) in those without physician involvement (p=0.001). Using multivariable logistic regression, prehospital physician involvement had an OR for a favourable neurological outcome of 3.44 (95% CI 1.64 to 7.23).

CONCLUSIONS

Among adults with out-of-hospital cardiac arrest, adding a physician-staffed ambulance was associated with significantly greater favourable neurological outcomes than standard emergency medical services.

2019 American Heart Association Focused Update on Advanced Cardiovascular Life Support: Use of Advanced Airways, Vasopressors, and Extracorporeal Cardiopulmonary Resuscitation During Cardiac Arrest: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

The fundamentals of cardiac resuscitation include the immediate provision of high-quality cardiopulmonary resuscitation combined with rapid defibrillation (as appropriate). These mainstays of therapy set the groundwork for other possible interventions such as medications, advanced airways, extracorporeal cardiopulmonary resuscitation, and post-cardiac arrest care, including targeted temperature management, cardiorespiratory support, and percutaneous coronary intervention. Since 2015, an increased number of studies have been published evaluating some of these interventions, requiring a reassessment of their use and impact on survival from cardiac arrest. This 2019 focused update to the American Heart Association advanced cardiovascular life support guidelines summarizes the most recent published evidence for and recommendations on the use of advanced airways, vasopressors, and extracorporeal cardiopulmonary resuscitation during cardiac arrest. It includes revised recommendations for all 3 areas, including the choice of advanced airway devices and strategies during cardiac arrest (eg, bag-mask ventilation, supraglottic airway, or endotracheal intubation), the training and retraining required, the administration of standard-dose epinephrine, and the decisions involved in the application of extracorporeal cardiopulmonary resuscitation and its potential impact on cardiac arrest survival.

Cuttings Transport Using Pulsed Drilling Fluid in the Horizontal Section of the Slim-Hole: An Experimental and Numerical Simulation Study

Poor transport of cuttings in horizontal sections of small-bore well holes leads to high torque and increases the risk of the drill becoming stuck, reducing its service life and posing a threat to safe operation. Because the conventional cuttings transport method cannot effectively remove the cuttings bed, a transport method using pulsed drilling fluid based on a shunt relay mechanism is proposed. A three-layer numerical simulation model of cuttings transport in horizontal small-bore wells is established. Using both experiments and numerical simulations, the cuttings transport is studied in terms of the moving cuttings velocity, cuttings concentration, and distance of movement of the cuttings bed. By varying the pulsed drilling fluid velocity cycle, amplitude, and duty cycle at the annulus inlet, their effects on cuttings transport are analyzed, and the optimal pulse parameters are determined. The results show that the use of pulsed drilling fluid can effectively enhance the moving cutting velocity and transport distance of the cuttings bed, reduce the cuttings concentration, and improve wellbore cleaning.

The effects of cardiac arrest recognition by dispatcher on Smart Advanced Life Support

Objectives:

The purpose of this study was to analyze the effect of cardiac arrest recognition by emergency medical dispatch on the pre-hospital advanced cardiac life support and to investigate the outcome of out-of-hospital cardiac arrest.

Method:

This study was conducted to evaluate the out-of-hospital cardiac arrest patients over 18 years of age, excluding trauma and poisoning patients, from 1 August 2015 to 31 July 2016. We investigated whether it was a cardiac-arrest recognition at dispatch. We compared the pre-hospital return of spontaneous circulation, the rate of survival admission and discharge, good neurological outcome, and also analyzed the time of securing vein, time of first epinephrine administration, and arrival time of paramedics.

Results:

A total of 3695 out-of-hospital cardiac arrest patients occurred during the study period, and 1468 patients were included in the study. Resuscitation rate by caller was significantly higher in the recognition group. The arrival interval between the first and second emergency service unit was shorter as 5.1 min on average, and the connection rate of paramedics and physicians before the arrival was 32.3%, which was significantly higher than that of the unrecognized group. The mean time required to first epinephrine administration was 13.1 min, which was significantly faster in the recognition group. However, there was no statistically significant difference between the two groups in patients with good neurological outcome, and rather the rate of return of spontaneous circulation and survival discharge was significantly higher in the non-recognition group.

Conclusion:

Although the recognition of cardiac arrest at dispatch does not directly affect survival rate and good neurological outcome, the activation of pre-hospital advanced cardiac life support and the shortening the time of epinephrine administration can increase pre-hospital return of spontaneous circulation. Therefore, effort to increase recognition by dispatcher is needed.

Impact of adrenaline dose and timing on out-of-hospital cardiac arrest survival and neurological outcomes

STUDY OBJECTIVE

The 2015 ILCOR Advanced Cardiovascular Life Support Guidelines recommend intravenous adrenaline (epinephrine) as a crucial pharmacologic treatment during cardiac arrest resuscitation. Some recent observational studies and clinical trials have questioned the efficacy of its use and suggested possible deleterious effects on overall survival and long-term outcomes. This study aimed to describe the association between time and dose of adrenaline on return of spontaneous circulation (ROSC) and neurologic function.

METHODS

We performed a retrospective analysis of the Penn Alliance for Therapeutic Hypothermia (PATH) data registry. The timing of the first dose of adrenaline and the total dose of adrenaline during cardiac arrests was compared between survivors to discharge and non-survivors for arrests lasting greater than 10 min.

RESULTS

The registry contained 5594 patients. After excluding patients with an in-hospital cardiac arrest, a non-shockable rhythm, or no adrenaline administration, 1826 were included in the final analysis. Survivors to discharge received adrenaline sooner (median 5.0 vs. 7.0 min, p = 0.022) and required a lower total dose than non-survivors (2.0 vs. 3.0 mg, p < 0.001). For survivors, there was no significant association between the time to first adrenaline dose and favorable neurological outcome as measured by Cerebral Performance Category (CPC). Among survivors, those that received less than 2 mg of adrenaline had a more favorable neurologic outcome than those administered > 3 mg. (CPC 1-2 16.6% vs. 12.5%, p = 0.004).

CONCLUSION

Early adrenaline administration is associated with a higher percentage of survival to discharge but not associated with favorable neurological outcome. Those patients with a favorable neurologic outcome received a lower total adrenaline dose prior to ROSC.

Time to epinephrine treatment is associated with the risk of mortality in children who achieve sustained ROSC after traumatic out-of-hospital cardiac arrest

Background

The benefits of early epinephrine administration in pediatric with nontraumatic out-of-hospital cardiac arrest (OHCA) have been reported; however, the effects in pediatric cases of traumatic OHCA are unclear. Since the volume-related pharmacokinetics of early epinephrine may differ obviously with and without hemorrhagic shock (HS), beneficial or harmful effects of nonselective epinephrine stimulation (alpha and beta agonists) may also be enhanced with early administration. In this study, we aimed to analyze the therapeutic effect of early epinephrine administration in pediatric cases of HS and non-HS traumatic OHCA.

Methods

This was a multicenter retrospective study (2003–2014). Children (aged ≤ 19 years) who experienced traumatic OHCA and were administered epinephrine for resuscitation were included. Children were classified into the HS (blood loss > 30% of total body fluid) and non-HS groups. The demographics, outcomes, postresuscitation hemodynamics (the first hour) after the sustained return of spontaneous circulation (ROSC), and survival durations were analyzed and correlated with the time to epinephrine administration (early < 15, middle 15–30, late > 30 min) in the HS and non-HS groups. Cox regression analysis was used to adjust for risk factors of mortality.

Results

A total of 509 children were included. Most of them (n = 348, 68.4%) had HS OHCA. Early epinephrine administration was implemented in 131 (25.7%) children. In both the HS and non-HS groups, early epinephrine administration was associated with achieving sustained ROSC (both p < 0.05) but was not related to survival or good neurological outcomes (without adjusting for confounding factors). However, early epinephrine administration in the HS group increased cardiac output but induced metabolic acidosis and decreased urine output during the initial postresuscitation period (all p < 0.05). After adjusting for confounding factors, early epinephrine administration was a risk factor of mortality in the HS group (HR 4.52, 95% CI 2.73–15.91).

Conclusion

Early epinephrine was significantly associated with achieving sustained ROSC in pediatric cases of HS and non-HS traumatic OHCA. For children with HS, early epinephrine administration was associated with both beneficial (increased cardiac output) and harmful effects (decreased urine output and metabolic acidosis) during the postresuscitation period. More importantly, early epinephrine was a risk factor associated with mortality in the HS group.

Effects of prehospital epinephrine administration on neurologically intact survival in bystander-witnessed out-of-hospital cardiac arrest patients with non-shockable rhythm depend on prehospital cardiopulmonary resuscitation duration required to hospital arrival

The effects of prehospital epinephrine administration on post-arrest neurological outcome in out-of-hospital cardiac arrest (OHCA) patients with non-shockable rhythm remain unclear. To examine the time-dependent effectiveness of prehospital epinephrine administration, we analyzed 118,396 bystander-witnessed OHCA patients with non-shockable rhythm from the prospectively recorded all-Japan OHCA registry between 2011 and 2014. Patients who achieved prehospital return of spontaneous circulation without prehospital epinephrine administration were excluded. Patients with prehospital epinephrine administration were stratified according to the time from the initiation of cardiopulmonary resuscitation (CPR) by emergency medical service (EMS) providers to the first epinephrine administration (≤ 10, 11-19, and ≥ 20 min). Patients without prehospital epinephrine administration were stratified according to the time from CPR initiation by EMS providers to hospital arrival (≤ 10, 11-19, and ≥ 20 min). The primary outcome was 1-month neurologically intact survival (cerebral performance category 1 or 2; CPC 1-2). Multivariate logistic regression analysis demonstrated that there was no significant difference in the chance of 1-month CPC 1-2 between patients who arrived at hospital in ≤ 10 min without prehospital epinephrine administration and patients with time to epinephrine administration ≤ 19 min. However, compared to patients who arrived at hospital in ≤ 10 min without prehospital epinephrine administration, patients with time to epinephrine administration ≥ 20 min and patients who arrived at hospital in 11-19, and ≥ 20 min without prehospital epinephrine administration were significantly associated with decreased chance of 1-month CPC 1-2 (p < 0.05, < 0.05, and < 0.001, respectively). In conclusion, when prehospital CPR duration from CPR initiation by EMS providers to hospital arrival estimated to be ≥ 11 min, prehospital epinephrine administered ≤ 19 min from CPR initiation by EMS providers could improve neurologically intact survival in bystander-witnessed OHCA patients with non-shockable rhythm.

Association of the time to first epinephrine administration and outcomes in out-of-hospital cardiac arrest: SOS-KANTO 2012 study

OBJECTIVE

This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.

METHODS

This was a post-hoc analysis of a multicenter prospective cohort study (SOS-KANTO 2012), which registered OHCA patients in the Kanto region of Japan from January 2012 to March 2013. We included consecutive adult OHCA patients who received epinephrine. The primary result included 1-month favorable neurological outcomes defined as cerebral performance category (CPC) 1 or 2. Secondary results included 1-month survival and return of spontaneous circulation (ROSC) after arrival at the hospital. Multivariable logistic regression analysis determined the association between delay per minute of the time from call to first EA in both pre- or in-hospital settings and outcomes.

RESULTS

Of the 16,452 patients, 9344 were eligible for our analyses. In univariable analysis, the delay in EA was associated with decreased favorable neurological outcomes only when the initial rhythm was a non-shockable rhythm. In multivariable analyses, delay in EA was associated with decreased ROSC (adjusted odds ratio [OR] for one minute delay, 0.97; 95% confidence interval [CI], 0.96-0.98) and 1-month survival (adjusted OR, 0.95; 95% CI, 0.92-0.97) when the initial rhythm was a non-shockable rhythm, whereas during a shockable rhythm, delay in EA was not associated with decreased ROSC and 1-month survival.

CONCLUSIONS

While assessing the effectiveness of epinephrine for OHCA, we should consider the time-limited effects of epinephrine. Additionally, consideration of early EA based on the pathophysiology is needed.

Epinephrine in Out-of-hospital Cardiac Arrest: Helpful or Harmful?

OBJECTIVE

Epinephrine is the primary drug administered during cardiopulmonary resuscitation (CPR) to reverse cardiac arrest. The evidence for the use of adrenaline in out-of-hospital cardiac arrest (OHCA) and in-hospital resuscitation is inconclusive. We conducted a systematic review on the clinical efficacy of adrenaline in adult OHCA patients to evaluate whether epinephrine provides any overall benefit for patients.

DATA SOURCES

The EMBASE and PubMed databases were searched with the key words "epinephrine," "cardiac arrest," and variations of these terms.

STUDY SELECTION

Data from clinical randomized trials, meta-analyses, guidelines, and recent reviews were selected for review.

RESULTS

Sudden cardiac arrest causes 544,000 deaths in China each year, with survival occurring in <1% of cases (compared with 12% in the United States). The American Heart Association recommends the use of epinephrine in patients with cardiac arrest, as part of advanced cardiac life support. There is a clear evidence of an association between epinephrine and increased return of spontaneous circulation (ROSC). However, there are conflicting results regarding long-term survival and functional recovery, particularly neurological outcome, after CPR. There is currently insufficient evidence to support or reject epinephrine administration during resuscitation. We believe that epinephrine may have a role in resuscitation, as administration of epinephrine during CPR increases the probability of restoring cardiac activity with pulses, which is an essential intermediate step toward long-term survival.

CONCLUSIONS

The administration of adrenaline was associated with improved short-term survival (ROSC). However, it appears that the use of adrenaline is associated with no benefit on survival to hospital discharge or survival with favorable neurological outcome after OHCA, and it may have a harmful effect. Larger placebo-controlled, double-blind, randomized control trials are required to definitively establish the effect of epinephrine.

Time to Epinephrine Administration and Survival From Nonshockable Out-of-Hospital Cardiac Arrest Among Children and Adults

BACKGROUND

Previous studies have demonstrated that earlier epinephrine administration is associated with improved survival from out-of-hospital cardiac arrest (OHCA) with shockable initial rhythms. However, the effect of epinephrine timing on patients with nonshockable initial rhythms is unclear. The objective of this study was to measure the association between time to epinephrine administration and survival in adults and children with emergency medical services (EMS)-treated OHCA with nonshockable initial rhythms.

METHODS

We performed a secondary analysis of OHCAs prospectively identified by the Resuscitation Outcomes Consortium network from June 4, 2011, to June 30, 2015. We included patients of all ages with an EMS-treated OHCA and an initial nonshockable rhythm. We excluded those with return of spontaneous circulation in <10 minutes. We conducted a subgroup analysis involving patients <18 years of age. The primary exposure was time (minutes) from arrival of the first EMS agency to the first dose of epinephrine. Secondary exposure was time to epinephrine dichotomized as early (<10 minutes) or late (≥10 minutes). The primary outcome was survival to hospital discharge. We adjusted for Utstein covariates and Resuscitation Outcomes Consortium study site.

RESULTS

From 55 568 EMS-treated OHCAs, 32 101 patients with initial nonshockable rhythms were included. There were 12 238 in the early group, 14 517 in the late group, and 5346 not treated with epinephrine. After adjusting for potential confounders, each minute from EMS arrival to epinephrine administration was associated with a 4% decrease in odds of survival for adults, odds ratio=0.96 (95% confidence interval, 0.95-0.98). A subgroup analysis (n=13 290) examining neurological outcomes showed a similar association (adjusted odds ratio, 0.94 per minute; 95% confidence interval, 0.89-0.98). When epinephrine was given late in comparison with early, odds of survival were 18% lower (odds ratio, 0.82; 95% confidence interval, 0.68-0.98). In a pediatric analysis (n=595), odds of survival were 9% lower (odds ratio, 0.91; 95% confidence interval, 0.81-1.01) for each minute delay in epinephrine.

CONCLUSIONS

Among OHCAs with nonshockable initial rhythms, the majority of patients were administered epinephrine >10 minutes after EMS arrival. Each minute delay in epinephrine administration was associated with decreased survival and unfavorable neurological outcomes. EMS agencies should consider strategies to reduce epinephrine administration times in patients with initial nonshockable rhythms.

Lower-dose epinephrine administration and out-of-hospital cardiac arrest outcomes

BACKGROUND

International guidelines recommend administration of 1 mg of intravenous epinephrine every 3-5 min during cardiac arrest. The optimal dose of epinephrine is not known. We evaluated the association of reduced frequency and dose of epinephrine with survival after out-of-hospital cardiac arrest (OHCA).

METHODS

Included were patients with non-traumatic OHCA treated by advanced life support (ALS) providers from January 1, 2008 to June 30, 2016. During the before period, providers were instructed to give epinephrine 1 mg intravenously at 4 min followed by additional 1 mg doses every eight minutes to patients with OHCA with a shockable rhythm and 1 mg doses every two minutes to patients with a non-shockable rhythm (higher dose). On October 1, 2012, providers were instructed to reduce the dose of epinephrine treatment during out-of-hospital cardiac arrest (OHCA): 0.5 mg at 4 and 8 min followed by additional doses of 0.5 mg every 8 min for shockable rhythms and 0.5 mg every 2 min for non-shockable rhythms (lower dose). Patients with shockable initial rhythms were analyzed separately from those with non-shockable initial rhythms. The primary outcome was survival to hospital discharge with a secondary outcome of favorable neurological status (Cerebral Performance Category [CPC] 1 or 2) at hospital discharge. Multiple logistic regression modeling was used to adjust for age, sex, presence of a witness, bystander CPR, and response interval.

RESULTS

2255 patients with OHCA were eligible for analysis. Of these, 24.6% had an initially shockable rhythm. Total epinephrine dose per patient decreased from a mean ± standard deviation of 3.4 ± 2.3 mg-2.6 ± 1.9 mg (p < 0.001) in the shockable group and 3.5 ± 1.9 mg-2.8 ± 1.7 mg (p < 0.001) in the non-shockable group. Among those with a shockable rhythm, survival to hospital discharge was 35.0% in the higher dose group vs. 34.2% in the lower dose group. Among those with a non-shockable rhythm, survival was 4.2% in the higher dose group vs. 5.1% in the lower dose group. Lower dose vs. higher dose was not significantly associated with survival: adjusted odds ratio, aOR 0.91 (95% CI 0.62-1.32, p = 0.61) if shockable and aOR 1.26 (95% CI 0.79-2.01, p = 0.33) if non-shockable. Lower dose vs. higher dose was not significantly associated with favorable neurological status at discharge: aOR 0.84 (95% CI 0.57-1.24, p = 0.377) if shockable and aOR 1.17 (95% CI 0.68-2.02, p = 0.577) if non-shockable.

CONCLUSION

Reducing the dose of epinephrine administered during out-of-hospital cardiac arrest was not associated with a change in survival to hospital discharge or favorable neurological outcomes after OHCA.

Impact of rapid response car system on ECMO in out-of-hospital cardiac arrest: A retrospective cohort study

INTRODUCTION

Extracorporeal life support (ECLS) has been reported to be more effective than conventional cardiopulmonary resuscitation (CPR). In ECLS, a shorter time from arrival to implantation of extracorporeal membrane oxygenation (ECMO; door-to-ECMO) time was predicted to be associated with better survival rates. This study aimed to examine the impact of the physician-based emergency medical services (P-EMS) using a rapid response car (RRC) on door-to-ECMO time in patients with out-of-hospital cardiac arrest (OHCA).

METHODS

In this retrospective cohort study, adult patients with OHCA who were admitted to a Japanese tertiary care hospital from April 2012 to December 2016 and underwent venoarterial ECMO were included. Patients were either transferred by emergency medical service (EMS only group) or RRC (RRC group). Primary outcome was door-to-ECMO time. Wilcoxon rank-sum test was used to compare the outcome between the two groups.

RESULTS

A total of 34 patients were included in this study, and outcome data were available for all patients. The door-to-ECMO time was significantly shorter in the RRC group than in the EMS only group (median, 23min vs. 36min; P=0.006). Additionally, the RRC was also associated with earlier successful intubation and intravenous adrenaline administration.

CONCLUSION

The physician-based RRC system was associated with a shorter door-to-ECMO time and successful advanced procedures in prehospital settings. Combination of the RRC system with ECLS may lead to better outcomes in patients with OHCA.

Impact of Early Vasopressor Administration on Neurological Outcomes after Prolonged Out-of-Hospital Cardiac Arrest

Introduction Vasopressors are associated with return of spontaneous circulation (ROSC), but no long-term benefit has been demonstrated in randomized trials. However, these trials did not control for the timing of vasopressor administration which may influence outcomes. Consequently, the objective of this study was to develop a model describing the likelihood of favorable neurological outcome (cerebral performance category [CPC] 1 or 2) as a function of the public safety answering point call receipt (PSAP)-to-pressor-interval (PPI) in prolonged out-of-hospital cardiac arrest. Hypothesis The likelihood of favorable neurological outcome declines with increasing PPI.

METHODS

This investigation was a retrospective study of cardiac arrest using linked data from the Cardiac Arrest Registry to Enhance Survival (CARES) database (Centers for Disease Control and Prevention [Atlanta, Georgia USA]; American Heart Association [Dallas, Texas USA]; and Emory University Department of Emergency Medicine [Atlanta, Georgia USA]) and the North Carolina (USA) Prehospital Medical Information System. Adult patients suffering a bystander-witnessed, non-traumatic cardiac arrest between January 2012 and June 2014 were included. Logistic regression was used to calculate the adjusted odds ratio (OR) of neurological outcome as a function of PPI, while controlling for patient age, gender, and race; endotracheal intubation (ETI); shockable rhythm; layperson cardiopulmonary resuscitation (CPR); and field hypothermia.

RESULTS

Of the 2,100 patients meeting inclusion criteria, 913 (43.5%) experienced ROSC, 618 (29.4%) survived to hospital admission, 187 (8.9%) survived to hospital discharge, and 155 (7.4%) were discharged with favorable neurological outcomes (CPC 1 or 2). Favorable neurological outcome was less likely with increasing PPI (OR=0.90; P<.01) and increasing age (OR=0.97; P<.01). Compared to patients with non-shockable rhythms, patients with shockable rhythms were more likely to have favorable neurological outcomes (OR=7.61; P<.01) as were patients receiving field hypothermia (OR=2.13; P<.01). Patient gender, non-Caucasian race, layperson CPR, and ETI were not independent predictors of favorable neurological outcome.

CONCLUSION

In this evaluation, time to vasopressor administration was significantly associated with favorable neurological outcome. Among adult, witnessed, non-traumatic arrests, the odds of hospital discharge with CPC 1 or 2 declined by 10% for every one-minute delay between PSAP call-receipt and vasopressor administration. These retrospective observations support the notion of a time-dependent function of vasopressor effectiveness on favorable neurological outcome. Large, prospective studies are needed to verify this relationship. Hubble MW , Tyson C . Impact of early vasopressor administration on neurological outcomes after prolonged out-of-hospital cardiac arrest. Prehosp Disaster Med. 2017; 32(3):297-304.