Increased return of spontaneous circulation at the expense of neurologic outcomes: Is prehospital epinephrine for out-of-hospital cardiac arrest really worth it?

The Impact on Patient Prognosis of Changes to the Method of Notifying Staff About Accepting Patients With Out-of-Hospital Cardiac Arrest

Background

Our hospital is a designated emergency hospital and accepts many patients with out-of-hospital cardiac arrest (OHCA). Previously, after receiving a direct call from emergency services to request acceptance of an OHCA patient, the emergency room (ER) chief nurse notified medical staff. However, this method delayed ER preparations, so a Code Blue system (CB) was introduced in which the pending arrival of an OHCA patient was broadcast throughout the hospital.

Methods

In this study, we retrospectively analyzed the impact of introducing CB at our hospital on OHCA patient prognosis to examine whether the introduction of CB is clinically meaningful. We compared consecutive cases treated before introduction of the CB (March 3, 2022, to March 22, 2023) with those treated afterwards (March 23, 2023, to July 23, 2024).

Results

A total of 30 cases per group were included. The mean number of medical staff present at admissions increased significantly from 5.4 ± 0.6 to 15.0 ± 3.0 (P < 0.001). Although not statistically significant, the introduction of the CB increased the return of spontaneous circulation (ROSC) rate from 20% to 30%, survival to discharge rate from 3% to 10%, and social reintegration rate from 0% to 3%. ROSC occurred in 15 patients. Among OHCA patients with cardiac disease, the ROSC rate tended to increase from 0% to 43% (P = 0.055). In addition, in OHCA patients with cardiac disease whose electrocardiogram initially showed ventricular fibrillation or pulseless electrical activity, the ROSC rate increased from 0% to 100%. ROSC tended to be influenced by the total number of staff and physicians present and the number of staff such as medical clerks, clinical engineers, and radiology technicians (P = 0.095, 0.076, 0.088, respectively).

Conclusions

Introduction of a CB may increase the ROSC rate and the number of patients surviving to discharge. It also appears to improve the quality of medical care by quickly gathering all necessary medical staff so that they can perform their predefined roles.

Efficacy of Intraosseous Versus Intravenous Drug Administration in Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

This meta-analysis compared the efficacy of intraosseous (IO) versus intravenous (IV) drug administration in out-of-hospital cardiac arrest (OHCA). We systematically searched Embase, Web of Science, PubMed, and Cochrane Library through September 20, 2024, for relevant studies. The primary outcome was favorable neurological outcome, with secondary outcomes, including survival to hospital discharge and return of spontaneous circulation (ROSC). Seventeen studies, including randomized controlled trials and observational studies, were included in the final analysis. Pooled results showed that IV access was associated with significantly better outcomes compared to IO access. Patients in the IV group had 1.73 times higher odds of favorable neurological outcomes (RR: 1.73, 95% CI: 1.32-2.27), 1.64 times higher odds of survival to hospital discharge (RR: 1.64, 95% CI: 1.27-2.12), and 1.27 times higher odds of ROSC (RR: 1.27, 95% CI: 1.16-1.40). However, significant heterogeneity was observed across studies for all outcomes. These findings suggest that IV access may be superior to IO access in improving outcomes for OHCA patients. However, the high heterogeneity and conflicting results from individual studies highlight the need for careful interpretation and further research. Factors such as ease of access, speed of establishment, and patient condition should also be considered when choosing between IV and IO routes during resuscitation. This meta-analysis underscores the importance of reassessing current guidelines and conducting more robust primary studies to optimize vascular access strategies in OHCA management.

Treatment Effects in Randomized and Nonrandomized Studies of Pharmacological Interventions: A Meta-Analysis

Importance

Randomized clinical trials (RCTs) are widely regarded as the methodological benchmark for assessing clinical efficacy and safety of health interventions. There is growing interest in using nonrandomized studies to assess efficacy and safety of new drugs.

Objective

To determine how treatment effects for the same drug compare when evaluated in nonrandomized vs randomized studies.

Data Sources

Meta-analyses published between 2009 and 2018 were identified in MEDLINE via PubMed and the Cochrane Database of Systematic Reviews. Data analysis was conducted from October 2019 to July 2024.

Study Selection

Meta-analyses of pharmacological interventions were eligible for inclusion if both randomized and nonrandomized studies contributed to a single meta-analytic estimate.

Data Extraction and Synthesis

For this meta-analysis using a meta-epidemiological framework, separate summary effect size estimates were calculated for nonrandomized and randomized studies within each meta-analysis using a random-effects model and then these estimates were compared. The reporting of this study followed the Guidelines for Reporting Meta-Epidemiological Methodology Research and relevant portions of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline.

Main Outcome and Measures

The primary outcome was discrepancies in treatment effects obtained from nonrandomized and randomized studies, as measured by the proportion of meta-analyses where the 2 study types disagreed about the direction or magnitude of effect, disagreed beyond chance about the effect size estimate, and the summary ratio of odds ratios (ROR) obtained from nonrandomized vs randomized studies combined across all meta-analyses.

Results

A total of 346 meta-analyses with 2746 studies were included. Statistical conclusions about drug benefits and harms were different for 130 of 346 meta-analyses (37.6%) when focusing solely on either nonrandomized or randomized studies. Disagreements were beyond chance for 54 meta-analyses (15.6%). Across all meta-analyses, there was no strong evidence of consistent differences in treatment effects obtained from nonrandomized vs randomized studies (summary ROR, 0.95; 95% credible interval [CrI], 0.89-1.02). Compared with experimental nonrandomized studies, randomized studies produced on average a 19% smaller treatment effect (ROR, 0.81; 95% CrI, 0.68-0.97). There was increased heterogeneity in effect size estimates obtained from nonrandomized compared with randomized studies.

Conclusions and Relevance

In this meta-analysis of treatment effects of pharmacological interventions obtained from randomized and nonrandomized studies, there was no overall difference in effect size estimates between study types on average, but nonrandomized studies both overestimated and underestimated treatment effects observed in randomized studies and introduced additional uncertainty. These findings suggest that relying on nonrandomized studies as substitutes for RCTs may introduce additional uncertainty about the therapeutic effects of new drugs.

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.

Association of intraosseous and intravenous access with patient outcome in out-of-hospital cardiac arrest

Here we report the results of a study on the association between drug delivery via intravenous route or intraosseous route in out-of-hospital cardiac arrest. Intraosseous drug delivery is considered an alternative option in resuscitation if intravenous access is difficult or impossible. Intraosseous uptake of drugs may, however, be compromised. We have performed a retrospective cohort study of all Danish patients with out-of-hospital cardiac arrest in the years 2016-2020 to investigate whether mortality is associated with the route of drug delivery. Outcome was 30-day mortality, death at the scene, no prehospital return of spontaneous circulation, and 7- and 90-days mortality. 17,250 patients had out-of-hospital cardiac arrest. 6243 patients received no treatment and were excluded. 1908 patients had sustained return of spontaneous circulation before access to the vascular bed was obtained. 2061 patients were unidentified, and 286 cases were erroneously registered. Thus, this report consist of results from 6752 patients. Drug delivery by intraosseous route is associated with increased OR of: No spontaneous circulation at any time (OR 1.51), Death at 7 days (OR 1.94), 30 days (2.02), and 90 days (OR 2.29). Intraosseous drug delivery in out-of-hospital cardiac arrest is associated with overall poorer outcomes than intravenous drug delivery.

Trend of Outcome Metrics in Recent Out-of-Hospital-Cardiac-Arrest Research: A Narrative Review of Clinical Trials

Cardiopulmonary resuscitation (CPR) research traditionally focuses on survival. In 2018, the International Liaison Committee on Resuscitation (ILCOR) proposed more patient-centered outcomes. Our narrative review assessed clinical trials after 2018 to identify the trends of outcome metrics in the field OHCA research. We performed a search of the PubMed database from 1 January 2019 to 22 September 2023. Prospective clinical trials involving adult humans were eligible. Studies that did not report any patient-related outcomes or were not available in full-text or English language were excluded. The articles were assessed for demographic information and primary and secondary outcomes. We included 89 studies for analysis. For the primary outcome, 31 (35%) studies assessed neurocognitive functions, and 27 (30%) used survival. For secondary outcomes, neurocognitive function was present in 20 (22%) studies, and survival was present in 10 (11%) studies. Twenty-six (29%) studies used both survival and neurocognitive function. Since the publication of the COSCA guidelines in 2018, there has been an increased focus on neurologic outcomes. Although survival outcomes are used frequently, we observed a trend toward fewer studies with ROSC as a primary outcome. There were no quality-of-life assessments, suggesting a need for more studies with patient-centered outcomes that can inform the guidelines for cardiac-arrest management.

Determination of Exogenous Adrenaline Levels in Patients Undergoing Cardiopulmonary Resuscitation

Core-shell quantum dot ZnS/CdSe screen-printed electrodes were used to electrochemically measure human blood plasma levels of exogenous adrenaline administered to cardiac arrest patients. The electrochemical behavior of adrenaline on the modified electrode surface was investigated using differential pulse voltammetry (DPV), cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). Under optimal conditions, the linear working ranges of the modified electrode were 0.001-3 μM (DPV) and 0.001-300 μM (EIS). The best limit of detection for this concentration range was 2.79 × 10^-8 μM (DPV). The modified electrodes showed good reproducibility, stability, and sensitivity and successfully detected adrenaline levels.

Association between a Post-Resuscitation Care Bundle and the Odds of Field Rearrest after Successful Resuscitation from Out-of-Hospital Cardiac Arrest: A Pre/Post Study

OBJECTIVES

Rearrest after successful resuscitation from out-of-hospital cardiac arrest (OHCA) is common and is associated with worse patient outcomes. However, little is known about the effect of interventions designed to prevent rearrest. We assessed the association between a prehospital care protocol for immediate management after return of spontaneous circulation (ROSC) and rates of field rearrest and survival to discharge in patients with prehospital ROSC.

METHODS

This was a retrospective study of adult patients with OHCA and field ROSC within a large EMS system before (April 2017-August 2018) and after (April 2019-February 2020) implementation of a structured prehospital post-ROSC care protocol. The protocol was introduced in September 2018 and provided on-scene stabilization direction including guidance on ventilation and blood pressure support. Field data and hospital outcomes were used to compare the frequency of field rearrest, hospital survival, and survival with good neurologic outcome before and after protocol implementation. Logistic regression was used to assess the association between the post-implementation period and these outcomes, and odds ratios were reported. The association between individual interventions on these outcomes was also explored.

RESULTS

There were 2,706 patients with ROSC after OHCA in the pre-implementation period and 1,780 patients in the post-implementation period. The rate of prehospital rearrest was 43% pre-implementation vs 45% post-implementation (RD 2%, 95% CI -1, 4%). In the adjusted analysis, introduction of the protocol was not associated with decreased odds of rearrest (OR 0.87, 95% CI 0.73, 1.04), survival to hospital discharge (OR 1.01, 95% CI 0.81, 1.24), or survival with good neurologic outcome (OR 0.81, 95% CI 0.61, 1.06). Post-implementation, post-ROSC administration of saline and push-dose epinephrine increased from 11% to 25% (RD 14%, 95% CI 11, 17%) and from 3% to 12% (RD 9% 95% CI 7, 11%), respectively. In an exploratory analysis, push-dose epinephrine was associated with a decreased odds of rearrest (OR 0.68, 95% CI 0.50, 0.94).

CONCLUSIONS

Introduction of a post-ROSC care protocol for patients with prehospital ROSC after OHCA was not associated with reduced odds of field rearrest. When elements of the care bundle were considered individually, push-dose epinephrine was associated with decreased odds of rearrest.

Esmolol, vector change, and dose-capped epinephrine for prehospital ventricular fibrillation or pulseless ventricular tachycardia

BACKGROUND

Refractory ventricular fibrillation (VF) and pulseless ventricular tachycardia (pVT) cardiac arrest describes a subset of patients who do not respond to standard Advanced Cardiac Life Support (ACLS) interventions and are associated with poor outcomes. Esmolol administration and vector change defibrillation have shown promise in improving outcomes in these patients, however evidence is limited.

OBJECTIVES

This study compares clinical outcomes between patients with prehospital refractory VF/pVT who received an Emergency Medical Service (EMS) bundle, comprised of esmolol administration, vector change defibrillation, and dose-capped epinephrine at 3 mg, to patients who received standard ACLS interventions.

METHODS

This multicenter, retrospective, cohort study evaluated medical records between October 18, 2017 and March 15, 2022. Patients were enrolled if they experienced a prehospital cardiac arrest with the rhythm VF or pVT, had received at least three standard defibrillations, at least 3 mg of epinephrine, and 300 mg of amiodarone. Patients who received the EMS bundle after its implementation were compared to patients who received standard ACLS interventions prior to its implementation. The primary outcome was sustained return of spontaneous circulation (ROSC), defined as ROSC lasting 20 min without recurrence of cardiac arrest. Secondary outcomes included the incidence of any ROSC, survival to hospital arrival, survival at hospital discharge, and neurologically intact survival at hospital discharge.

RESULTS

Eighty-three patients were included in the study. Thirty-six were included in the pre-EMS bundle group and 47 patients were included in the post-EMS bundle group. Patients in the pre-EMS bundle group achieved significantly higher rates of sustained ROSC (58.3% vs 17%, p < 0.001), any ROSC (66.7% vs 19.1%, p < 0.001), and survival to hospital arrival (55.6% vs 17%, p < 0.001). The rates of survival to hospital discharge (16.7% vs 6.4%, p = 0.17) and neurologically intact survival at hospital discharge (5.9% vs 4.3%, p = 1.00) were not significantly different between groups.

CONCLUSIONS

Patients who received the EMS bundle achieved sustained ROSC significantly less often and were less likely to have pulses at hospital arrival. The incidence of neurologically intact survival was low and similar between groups.

Therapeutic and adverse effects of adrenaline on patients who suffer out-of-hospital cardiac arrest: a systematic review and meta-analysis

OBJECTIVE

The efficacy and safety of epinephrine in patients with out-of-hospital cardiac arrest (OHCA) remains controversial. The meta-analysis was used to comprehensively appraise the influence of epinephrine in OHCA patients.

METHODS

We searched all randomized controlled and cohort studies published by PubMed, EMBASE, and Cochrane Library from the inception to August 2022 on the prognostic impact of epinephrine on patients with OHCA. Survival to discharge was the primary outcome, while the return of spontaneous circulation (ROSC) and favorable neurological outcome were secondary outcomes.

RESULTS

The meta-analysis included 18 studies involving 863,952 patients. OHCA patients with adrenaline had an observably improved chance of ROSC (RR 2.81; 95% CI 2.21-3.57; P = 0.001) in randomized controlled studies, but the difference in survival to discharge (RR 1.27; 95% CI 0.58-2.78; P = 0.55) and favorable neurological outcomes (RR 1.21; 95% CI 0.90-1.62; P = 0.21) between the two groups was not statistically significant. In cohort studies, the rate of ROSC (RR 1.62; 95% CI 1.14-2.30; P = 0.007) increased significantly with the adrenaline group, while survival to discharge (RR 0.73; 95% CI 0.55-0.98; P = 0.03) and favorable cerebral function (RR 0.42; 95% CI 0.30-0.58; P = 0.001) were lower than the non-adrenaline group.

CONCLUSION

We found that both the randomized controlled trials (RCTs) and cohort studies showed that adrenaline increased ROSC in OHCA patients. However, they were unable to agree on a long-term prognosis. The cohort studies showed that adrenaline had an adverse effect on the long-term prognosis of OHCA patients (discharge survival rate and good neurological prognosis), but adrenaline had no adverse effect in the RCTs. In addition to the differences in research methods, there are also some potential confounding factors in the included studies. Therefore, more high-quality studies are needed to fully confirm the effect of adrenaline on the long-term results of OHCA.

Temporal Changes in Epinephrine Dosing in Out-of-Hospital Cardiac Arrest: A Review of EMS Protocols across the United States

BACKGROUND

Administration of epinephrine has been associated with worse neurological outcomes for survivors of out-of-hospital cardiac arrest. The publication of the 2018 PARAMEDIC-2 trial, a randomized and double-blind study of epinephrine in out-of-hospital cardiac arrest, provides the strongest evidence to date that epinephrine increases return of spontaneous circulation (ROSC) but not neurologically intact survival. This study aims to determine if Emergency Medical Services (EMS) cardiac arrest protocols have changed since the publication of PARAMEDIC-2.

METHODS

States in the US utilizing mandatory or model state-wide EMS protocols, including Washington DC, were included in this study. The nontraumatic cardiac arrest protocol as of January 1, 2018 was compared to the protocol in effect on January 1, 2021 to determine if there was a change in the administration of epinephrine. Protocols were downloaded from the relevant state EMS website. If a protocol could not be obtained, the state medical director was contacted.

RESULTS

A 2021 state-wide protocol was found for 32/51 (62.7%) states. Data from 2018 were available for 21/51 (41.2%) states. Of the 11 states without data from 2018, all follow Advanced Cardiac Life Support (ACLS) guidelines in the 2021 protocol. Five (15.6%) of the states with a state-wide protocol made a change in the cardiac arrest protocols. Maximum cumulative epinephrine dose was limited to 4mg in Maryland and 3mg in Vermont. Rhode Island changed epinephrine in shockable rhythms to be administered after three cycles of cardiopulmonary resuscitation (CPR) and an anti-arrhythmic. Rhode Island also added an epinephrine infusion as an option. No states removed epinephrine administration from their cardiac arrest protocol. Simple statistical analysis was performed with Microsoft Excel.

CONCLUSION

Several states have adjusted cardiac arrest protocols since 2018. The most frequent change was limiting the maximum cumulative dosage of epinephrine. One state changed timing of epinephrine dosing depending on the rhythm and also provided an option of an epinephrine infusion in place of bolus dosing. While the sample size is small, these changes may reflect the future direction of prehospital cardiac arrest protocols. Significant limitations apply, including the exclusion of local and regional protocols which are more capable of quickly adjusting to new research. Additionally, this study is only focused on EMS in the United States.

Characterization of cerebral blood flow during open cardiac massage in swine: Effect of volume status

Introduction: Patients in cardiac arrest treated with resuscitative thoracotomy and open cardiac massage (OCM) have high rates of mortality with poor neurological outcomes. The aim of this study is to quantitate cerebral perfusion during OCM using computed tomography perfusion (CTP) imaging in a swine model of normo- and hypovolemia.

Methods: Anesthetized swine underwent instrumentation with right atrial and aortic pressure catheters. A catheter placed in the ascending aorta was used to administer iodinated contrast and CTP imaging acquired. Cerebral blood flow (CBF; ml/100 g of brain) and time to peak (TTP; s) were measured. Animals were then euthanized by exsanguination (hypovolemic group) or potassium chloride injection (normovolemic group) and subjected to a clamshell thoracotomy, aortic cross clamping, OCM, and repeated CTP. Data pertaining to peak coronary perfusion pressure (pCoPP; mmHg) were collected and % CoPP > 15 mmHg (% CoPP; s) calculated post hoc.

Results: Normovolemic animals (n = 5) achieved superior pCoPP compared to the hypovolemic animals (n = 5) pCoPP (39.3 vs. 12.3, p < 0.001) and % CoPP (14.5 ± 1.9 vs. 30.9 ± 6.5, p < 0.001). CTP acquisition was successful and TTP elongated from spontaneous circulation, normovolemia to hypovolemia (5.7 vs. 10.8 vs. 14.8, p = 0.01). CBF during OCM was similar between hypovolemic and normovolemic groups (7.5 ± 8.1 vs. 4.9 ± 6.0, p = 0.73) which was significantly lower than baseline values (51.9 ± 12.1, p < 0.001).

Conclusion: OCM in normovolemia generates superior coronary hemodynamics compared to hypovolemia. Despite this, neither generates adequate CBF as measured by CTP, compared to baseline. To improve the rate of neurologically intact survivors, novel resuscitative techniques need to be investigated that specifically target cerebral perfusion as existing techniques are inadequate.

Clinical Validation of Cardiac Arrest Hospital Prognosis (CAHP) Score and MIRACLE2 Score to Predict Neurologic Outcomes after Out-of-Hospital Cardiac Arrest

Background. Out-of-hospital cardiac arrest (OHCA) remains a challenge for emergency physicians, given the poor prognosis. In 2020, MIRACLE2, a new and easier to apply score, was established to predict the neurological outcome of OHCA. Objective. The aim of this study is to compare the discrimination of MIRACLE2 score with cardiac arrest hospital prognosis (CAHP) score for OHCA neurologic outcomes. Methods. This retrospective cohort study was conducted between January 2015 and December 2019. Adult patients (>17 years) with cardiac arrest who were brought to the hospital by an emergency medical service crew were included. Deaths due to trauma, burn, drowning, resuscitation not initiated due to pre-ordered “do not resuscitate” orders, and patients who did not achieve return of spontaneous circulation were excluded. Receiver operating characteristic curve analysis with Youden Index was performed to calculate optimal cut-off values for both scores. Results. Overall, 200 adult OHCA cases were analyzed. The threshold of the MIRACLE2 score for favorable neurologic outcomes was 5.5, with an area under the curve (AUC) value of 0.70 (0.61−0.80, p < 0.001); the threshold of the CAHP score was 223.4, with an AUC of 0.77 (0.68−0.86, p < 0.001). On setting the MIRACLE2 score cut-off value, we documented 64.7% sensitivity (95% confidence interval [CI], 56.9−71.9%), 66.7.0% specificity (95% CI, 48.2−82.0%), 90.8% positive predictive value (PPV; 95% CI, 85.6−94.2%), and 27.2% negative predictive value (NPV; 95% CI, 21.4−33.9%). On establishing a CAHP cut-off value, we observed 68.2% sensitivity (95% CI, 60.2−75.5%), 80.6% specificity (95% CI, 62.5−92.6%), 94.6% PPV (95% CI, 88.6%−98.0%), and 33.8% NPV (95% CI, 23.2−45.7%) for unfavorable neurologic outcomes. Conclusions. The CAHP score demonstrated better discrimination than the MIRACLE2 score, affording superior sensitivity, specificity, PPV, and NPV; however, the CAHP score remains relatively difficult to apply. Further studies are warranted to establish scores with better discrimination and ease of application.

Effect of adrenaline dose on neurological outcome in out-of-hospital cardiac arrest: a nationwide propensity score analysis

BACKGROUND

Adrenaline is recommended during cardio-pulmonary resuscitation. The optimal dose remains debated, and the effect of lower than recommended dose is unknown.

OBJECTIVE

To compare the outcome of patients treated with the recommended, lower or higher cumulative doses of adrenaline.

DESIGN, SETTINGS, PARTICIPANTS

Patients were included from the French National Cardiac Arrest Registry and were grouped based on the received dose of adrenaline: recommended, higher and lower dose.

OUTCOME MEASURES AND ANALYSIS

The primary endpoint was good neurologic outcome at 30 days post-OHCA, defined by a cerebral performance category (CPC) of less than 3. Secondary endpoints included return of spontaneous circulation and survival to hospital discharge. A multiple propensity score adjustment approach was performed.

MAIN RESULTS

27 309 patients included from July 1st 2011 to January 1st 2019 were analysed, mean age was 68 (57-78) years and 11.2% had ventricular fibrillation. 588 (2.2%) patients survived with a good CPC score. After adjustment, patients in the high dose group had a significant lower rate of good neurologic outcome (OR, 0.6; 95% CI, 0.5-0.7). There was no significant difference for the primary endpoint in the lower dose group (OR, 0.8; 95% CI, 0.7-1.1). There was a lower rate of survival to hospital discharge in the high-dose group vs. standard group (OR, 0.5; 95% CI, 0.5-0.6).

CONCLUSION

The use of lower doses of adrenaline was not associated with a significant difference on survival good neurologic outcomes at D30. But a higher dose of adrenaline was associated with a lower rate of survival with good neurological outcomes and poorer survival at D30.

Effect of Prehospital Epinephrine on Out-of-Hospital Cardiac Arrest Outcomes: A Propensity Score-Matched Analysis

PURPOSE

A pilot project using epinephrine at the scene under medical control is currently underway in Korea. This study aimed to determine whether prehospital epinephrine administration is associated with improved survival and neurological outcomes in out-of-hospital cardiac arrest (OHCA) patients who received epinephrine during cardiopulmonary resuscitation (CPR) in the emergency department.

MATERIALS AND METHODS

This retrospective observational study used a nationwide multicenter OHCA registry. Patients were classified into two groups according to whether they received epinephrine at the scene or not. The associations between prehospital epinephrine use and outcomes were assessed using propensity score (PS)-matched analysis. Multivariable logistic regression analysis was performed using PS matching. The same analysis was repeated for the subgroup of patients with non-shockable rhythm.

RESULTS

PS matching was performed for 1084 patients in each group. Survival to discharge was significantly decreased in the patients who received prehospital epinephrine [odds ratio (OR) 0.415, 95% confidence interval (CI) 0.250-0.670, p<0.001]. However, no statistical significance was observed for good neurological outcome (OR 0.548, 95% CI 0.258-1.123, p=0.105). For the patient subgroup with non-shockable rhythm, prehospital epinephrine was also associated with lower survival to discharge (OR 0.514, 95% CI 0.306-0.844, p=0.010), but not with neurological outcome (OR 0.709, 95% CI 0.323-1.529, p=0.382).

CONCLUSION

Prehospital epinephrine administration was associated with decreased survival rates in OHCA patients but not statistically associated with neurological outcome in this PS-matched analysis. Further research is required to investigate the reason for the detrimental effect of epinephrine administered at the scene.

Administration of epinephrine by advanced emergency medical technicians for out-of-hospital cardiac arrest in a rural emergency medical services system

OBJECTIVE

Epinephrine in out-of-hospital cardiac arrest (OHCA) remains controversial and understudied in rural emergency medical services (EMS) systems. We evaluated the effects of allowing advanced emergency medical technicians (AEMTs) to administer epinephrine during OHCA in a rural EMS system.

METHODS

An interrupted time series study was conducted using statewide EMS electronic records. Patients with OHCA before (phase I) and after (phase II) a protocol change expanding the AEMT scope of practice to include epinephrine for OHCA were identified. Number and timing of initial epinephrine administration, return of spontaneous circulation, and 30-day survival rates were compared using descriptive statistics, logistic regression, regression discontinuity, and propensity score matching.

RESULTS

A total of 1037 OHCAs met the inclusion criteria. In phase 1 compared with phase 2, 275 (56.12%) patients received epinephrine versus 624 (83.53%; P < 0.001). The mean time to first administration of epinephrine for unwitnessed and bystander-witnessed OHCA were 11.73 minutes versus 8.17 minutes (P < 0.001) and 11.59 minutes versus 8.85 minutes (P < 0.01), respectively. Unadjusted analysis showed a decrease in 30-day survival rates among patients receiving epinephrine from 18.01% to 12.66% (P < 0.05). Adjusted analysis showed an increase in 30-day survival with decreased time to first epinephrine dose(OR 0.960, 1.005; 95% confidence interval, 0.929, 0.992).

CONCLUSION

Adding epinephrine for OHCA to the AEMT scope of practice was associated with an increased percentage of patients receiving epinephrine and decreased time to first administration of epinephrine for patients with unwitnessed OHCA. Unadjusted analysis showed a decrease in 30-day survival rates among patients receiving epinephrine. Adjusted analysis found that earlier administrationof epinephrine was associated with increased ROSC and 30-day survival.

Drug use during adult advanced cardiac life support: An overview of reviews

AIM

To conduct an overview of systematic reviews and meta-analyses to summarize the ever-growing evidence on drug use during advanced life support.

METHODS

We searched Embase, Medline, Cochrane central register of controlled trials and Web of science for systematic reviews and meta-analyses reporting on drug use during advanced life support from inception to March, 2020. Two reviewers independently assessed all abstracts for eligibility, extracted data and assessed risk of bias using the AMSTAR-2 tool. Corrected covered areas were calculated from publication citation matrices to account for potential risk of bias. Data were graphically represented using forest plots.

RESULTS

Twenty-two head-to-head drug comparisons from 47 included articles were analysed. Adrenaline significantly increases the incidence of return of spontaneous circulation and survival to hospital discharge, but not the incidence of neurological intact survival. Vasopressin alone or in combination with adrenaline is not superior to adrenaline alone. There is a trend favouring lidocaine over amiodarone in shockable cardiac arrest. The risk of bias assessment of included studies ranged from very low to very high and the overlap between articles was moderate to high.

CONCLUSIONS

In line with the guidelines, we currently suggest that a standard dose of adrenaline should be administered during resuscitation, however, studies assessing lower doses of adrenaline are pressing. There is no rationale for the combination of vasopressin and adrenaline or vasopressin alone instead of adrenaline. In addition, lidocaine is a valuable alternative for amiodarone and maybe even preferable for shockable cardiac arrest. However more research is necessary.

Influence of the prehospital administered dosage of epinephrine on the plasma levels of catecholamines in patients with out-of-hospital cardiac arrest

Aim

This study evaluated whether the prehospital administered dosage of epinephrine (Ep) influences the plasma levels of catecholamines in patients with out-of-hospital cardiac arrest (OHCA).

Methods

This was a prospective, observational clinical study. Patients with OHCA transferred to our hospital between July 2014 and July 2017 were analyzed. The plasma levels of catecholamines were measured using blood samples obtained immediately upon arrival at the hospital and before the administration of Ep. Patients were divided into three groups based on the prehospital administered dosage of Ep: no prehospital administration (group Z); 1 mg of Ep (group O); and 2 mg of Ep (group T). The levels of catecholamines, as well as the conditions of resuscitation prior to and after arrival at the hospital were compared between the three groups.

Results

We analyzed 145 patients with OHCA (96, 38, and 11 patients in groups Z, O, and T, respectively). Group T exhibited the highest plasma levels of Ep with a statistically significant difference, however, there were no significant differences in the plasma levels of norepinephrine (Nep), dopamine (DOA) and vasopressin (ADH) among the three groups.

Conclusion

The prehospital administered dosage of Ep influences the plasma levels of Ep; however, it does not contribute to the plasma levels of Nep, DOA and ADH in patients with OHCA.

Effect of Epinephrine Administered during Cardiopulmonary Resuscitation on Cerebral Oxygenation after Restoration of Spontaneous Circulation in a Swine Model with a Clinically Relevant Duration of Untreated Cardiac Arrest

Severe neurological impairment was more prevalent in cardiac arrest survivors who were administered epinephrine than in those administered placebo in a randomized clinical trial; short-term reduction of brain tissue O2 tension (PbtO2) after epinephrine administration in swine following a short duration of untreated cardiac arrest has also been reported. We investigated the effects of epinephrine administered during cardiopulmonary resuscitation (CPR) on cerebral oxygenation after restoration of spontaneous circulation (ROSC) in a swine model with a clinically relevant duration of untreated cardiac arrest. After 7 min of ventricular fibrillation, 24 pigs randomly received either epinephrine or saline placebo during CPR. Parietal cortex measurements during 60-min post-resuscitation period showed that the area under the curve (AUC) for PbtO2 was smaller in the epinephrine group than in the placebo group during the initial 10-min period and subsequent 50-min period (both p < 0.05). The AUC for number of perfused cerebral capillaries was smaller in the epinephrine group during the initial 10-min period (p = 0.005), but not during the subsequent 50-min period. In conclusion, epinephrine administered during CPR reduced PbtO2 for longer than 10 min following ROSC in a swine model with a clinically relevant duration of untreated cardiac arrest.

Long term outcomes of participants in the PARAMEDIC2 randomised trial of adrenaline in out-of-hospital cardiac arrest

AIMS

We recently reported early outcomes in patients enrolled in a randomised trial of adrenaline in out-of-hospital cardiac arrest: the PARAMEDIC2 (Prehospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug Administration in Cardiac Arrest) trial. The purpose of the present paper is to report long-term survival, quality of life, functional and cognitive outcomes at 3, 6 and 12-months.

METHODS

PARAMEDIC2 was a pragmatic, individually randomised, double blind, controlled trial with an economic evaluation. Patients were randomised to either adrenaline or placebo. This paper reports results on the modified Rankin Scale scores at 6-months, survival at 6 and 12-months, as well as other cognitive, functional and quality of life outcomes collected at 3 and 6 months (Two Simple Questions, the Mini Mental State Examination, the Informant Questionnaire on Cognitive Decline Evaluation for Cardiac Arrest, Hospital Anxiety and Depression Scale, the Post Traumatic Stress Disorder Checklist - Civilian Version, Short-Form 12-item Health Survey and the EuroQoL EQ-5D-5L).

RESULTS

8014 patients were randomised with confirmed trial drug administration. At 6-months, 78 (2.0%) of the patients in the adrenaline group and 58 (1.5%) of patients in the placebo group had a favourable neurological outcome (adjusted odds ratio 1.35 [95% confidence interval: 0.93, 1.97]). 117 (2.9%) patients were alive at 6-months in the adrenaline group compared with 86 (2.2%) in the placebo group (1.43 [1.05, 1.96], reducing to 107 (2.7%) and 80 (2.0%) respectively at 12-months (1.38 [1.00, 1.92]). Measures of 3 and 6-month cognitive, functional and quality of life outcomes were reduced, but there was no strong evidence of differences between groups.

CONCLUSION

Adrenaline improved survival through to 12-months follow-up. The study did not find evidence of improvements in favourable neurological outcomes. (ISCRTN 73485024).

Resuscitating Resuscitation: Advanced Therapies for Resistant Ventricular Dysrhythmias

BACKGROUND

More than 640,000 combined in-hospital and out-of-hospital cardiac arrests occur annually in the United States. However, survival rates and meaningful neurologic recovery remain poor. Although "shockable" rhythms (i.e., ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT)) have the best outcomes, many of these ventricular dysrhythmias fail to return to a perfusing rhythm (resistant VF/VT), or recur shortly after they are resolved (recurrent VF/VT).

OBJECTIVE

This review discusses 4 emerging therapies in the emergency department for treating these resistant or recurrent ventricular dysrhythmias: beta-blocker therapy, dual simultaneous external defibrillation, stellate ganglion blockade, and extracorporeal cardiopulmonary resuscitation. We discuss the underlying physiology of each therapy, review relevant literature, describe when these approaches should be considered, and provide evidence-based recommendations for these techniques.

DISCUSSION

Esmolol may mitigate some of epinephrine's negative effects when used during resuscitation, improving both postresuscitation cardiac function and long-term survival. Dual simultaneous external defibrillation targets the region of the heart where ventricular fibrillation typically resumes and may apply a more efficient defibrillation across the heart, leading to higher rates of successful defibrillation. Stellate ganglion blocks, recently described in the emergency medicine literature, have been used to treat patients with recurrent VF/VT, resulting in significant dysrhythmia suppression. Finally, extracorporeal cardiopulmonary resuscitation is used to provide cardiopulmonary support while clinicians correct reversible causes of arrest, potentially resulting in improved survival and good neurologic functional outcomes.

CONCLUSION

These emerging therapies do not represent standard practice; however, they may be considered in the appropriate clinical scenario when standard therapies are exhausted without success.

Polypharmacy prior to in-hospital cardiac arrest among patients with cardiopulmonary diseases: A pilot study

Background

Patterns of medication administration prior to in-hospital cardiac arrest (I-HCA) and the potential impact of these on patient outcomes is not well-established. Accordingly, types of medications administered in the 72 h prior to I-HCA were examined in relation to initial rhythms of I-HCA and survival.

Methods

A retrospective, pilot study was conducted among 96 patients who experienced I-HCA. Clinical characteristics and treatments including medications were extracted from electronic health records. Relative risk (RR) of medications or class of medications associated with the initial rhythms of I-HCA and return of spontaneous circulation (ROSC) were calculated.

Results

Two distinct sub-groups were identified that did not survive to hospital discharge (n = 31): 1) those who received either vasopressin/desmopressin (n = 16) and 2) those who received combinations of psychotherapeutic agents with anxiolytics, sedatives, and hypnotics (n = 15) prior to I-HCA. The risk of pulseless electrical activity and asystolic arrest was high in patients who received sympathomimetic agents alone or in combination with β-Adrenergic blocking agents, (RR = 1.40, 1.41, respectively). Vasopressin and a combination of vasopressin and fentanyl were associated with risk of unsuccessful ROSC (RR = 2.50, 2.38, respectively).

Conclusions

The types of medications administered during inpatient care may serve as a surrogate marker for identifying patients at risk of specific initial rhythms of I-HCA and survival.

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.

A Time-Dependent Propensity Score Matching Approach to Assess Epinephrine Use on Patients Survival Within Out-of-Hospital Cardiac Arrest Care

BACKGROUND

Epinephrine effectiveness and safety are still questioned. It is well known that the effect of epinephrine varies depending on patients' rhythm and time to injection.

OBJECTIVE

We aimed to assess the association between epinephrine use during out-of-hospital cardiac arrest (OHCA) care and patient 30-day (D30) survival.

METHODS

Between 2011 and 2017, 27,008 OHCA patients were included from the French OHCA registry. We adjusted populations using a time-dependent propensity score matching. Analyses were stratified according to patient's first rhythm. After matching, 2837 pairs of patients with a shockable rhythm were created and 20,950 with a nonshockable rhythm.

RESULTS

Whatever the patient's rhythm (shockable or nonshockable), epinephrine use was associated with less D30 survival (odds ratio [OR] 0.508; 95% confidence interval [CI] 0.440-0.586] and OR 0.645; 95% CI 0.549-0.759, respectively). In shockable rhythms, on all outcomes, epinephrine use was deleterious. In nonshockable rhythms, no difference was observed regarding return of spontaneous circulation and survival at hospital admission. However, epinephrine use was associated with worse neurological prognosis (OR 0.646; 95% CI 0.549-0.759).

CONCLUSIONS

In shockable and nonshockable rhythms, epinephrine does not seem to have any benefit on D30 survival. These results underscore the need to perform further studies to define the optimal conditions for using epinephrine in patients with OHCA.

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.

Does second EMS unit response time affect outcomes of OHCA in multi-tiered system? A nationwide observational study

OBJECTIVES

The time dependence of a multi-tier response for out-of-hospital cardiac arrest (OHCA) is unclear. The aim of this study was to evaluate the time-dependent effect of EMS response type in a multi-tiered system on the clinical outcomes of OHCA.

METHODS

Adult EMS-treated OHCA of presumed cardiac etiology who were not witnessed by EMS between January 2015 and December 2017 were included. The main exposure was EMS response type: single-tier response, early multi-tier response (0-18 min from call to second EMS arrival), and late multi-tier response (19 min from call to second EMS arrival). The primary outcome was good neurologic recovery at the time of discharge from the hospital. Multivariate logistic regression analysis was performed, adjusting for patient-community and prehospital variables.

RESULTS

Among 54,436 patients, 29,995 patients (55.1%), 21,552 patients (39.6%), and 2889 patients (5.3%) were treated by single-tiered EMS, early multi-tiered EMS, and late multi-tiered EMS, respectively. Good neurological recovery and survival to discharge were more frequent in the early multi-tiered response group (6.4% and 9.7%) than in the single-tiered response group (4.8% and 7.5%) or late multi-tiered response group (3.1% and 5.8%). Compared to the single-tiered response group, the early multi-tiered response group was more likely to have good neurological recovery (adjusted OR, 95% CI: 1.15 [1.06-1.26]), but the late multi-tiered response group was less likely to have good neurological recovery (adjusted OR, 95% CI: 0.76 [0.61-0.96]).

CONCLUSION

In our basic to intermediate-tiered EMS system, early multi-tier response was associated with improved survival and good neurological recovery.

Prehospital Epinephrine as a Potential Factor Associated with Prehospital Rearrest

Objective: To investigate the impact of epinephrine on prehospital rearrest and re-attainment of prehospital return of spontaneous circulation (ROSC). Methods: Data for 9,292 (≥ 8 years) out-of-hospital cardiac arrest (OHCA) patients transported to hospitals by emergency medical services were collected in Ishikawa Prefecture, Japan during 2010-2018. Univariate and multivariable analyses were retrospectively performed for 1,163 patients with prehospital ROSC. Results: Of 1,163 patients, rearrest occurred in 272 (23.4%) but not in 891 (76.6%). Both single and multiple doses of epinephrine administered before prehospital ROSC (adjusted odds ratio (OR): 3.62, 95% confidence interval (CI): 2.42-5.46 for 1 mg, and 4.27, 2.58-6.79 for ≥ 2 mg) were main factors associated with rearrest. The association between initial and rearrest rhythms was significantly associated with epinephrine administration (p = 0.02). However, the rearrest rhythm was primarily associated with the initial rhythm (p < 0.01). The majority of patients with the non-shockable initial rhythm had pulseless electrical activity (PEA) as the rearrest rhythm, regardless of epinephrine administration (80.4% for administration, 81.6% for no administration). When the initial rhythm was shockable, the primary rearrest rhythms in patients with and without epinephrine administration before prehospital ROSC were PEA (52.2%) and ventricular fibrillation/pulseless ventricular tachycardia (56.8%), respectively. Only epinephrine administration after rearrest was associated with prehospital re-attainment of ROSC (adjusted OR: 2.49, 95% CI: 1.20-5.19). Stepwise multivariable logistic regression analyses revealed that neurologically favorable outcome was poorer in patients with rearrest than those without rearrest (9.9% vs. 25.0%, adjusted OR: 0.42, 95% CI: 0.23-0.73). The total prehospital doses of epinephrine were associated with poorer neurological outcome in a dose-dependent manner (adjusted OR: 0.22, 95% CI: 0.13-0.36 for 1 mg; 0.09, 0.04-0.19 for 2 mg; 0.03, 0.01-0.09 for ≥ 3 mg, no epinephrine as a reference). Transportation to hospitals with a unit for post-resuscitation care was associated with better neurological outcome (adjusted OR: 1.53, 95% CI: 1.02-2.32). Conclusions: The requirement for epinephrine administration before prehospital ROSC was associated with subsequent rearrest. Routine epinephrine administrations and rearrest were associated with poorer neurological outcome of OHCA patients with prehospital ROSC.

Intravenous versus intraosseous adrenaline administration in out-of-hospital cardiac arrest: A retrospective cohort study

BACKGROUND

Adrenaline is an important component in the resuscitation of individuals experiencing out-of-hospital cardiac arrest (OHCA). The 2018 Advanced Cardiac Life Support (ACLS) algorithm gives the option of either intravenous (IV) or intraosseous (IO) routes for adrenaline administration during cardiac arrest. However, the optimal route during prehospital resuscitation remains controversial. This study aims to investigate whether IV and IO routes lead to different outcomes in OHCA patients who received prehospital adrenaline.

METHODS

This retrospective analysis included adult patients with OHCA of presumed cardiac origin who had Emergency Medical Services (EMS) CPR, received adrenaline, and were enrolled in the Resuscitation Outcomes Consortium (ROC) Cardiac Epistry version 3 database between 2011 and 2015. We divided the study population into IV and IO groups based on the administration route. Logistic regression analysis was performed to evaluate the association between adrenaline delivery routes and prehospital return of spontaneous circulation (ROSC), survival to hospital discharge, and favorable neurological outcome.

RESULTS

Of the 35,733 patients included, 27,758 (77.7%) had adrenaline administered via IV access and 7975 (22.3%) via IO access. With the IO group as a reference in the logistic regression model, the adjusted odds ratios of the IV group for prehospital ROSC, survival and favorable neurological outcome were 1.367 (95%CI, 1.276-1.464), 1.468 (95%CI, 1.264-1.705) and 1.849 (95%CI, 1.526-2.240), respectively. Similar results were found in the propensity score matched population and subgroup analysis.

CONCLUSION

Compared with the IO approach, the IV approach appears to be the optimal route for adrenaline administration in advanced life support for OHCA during prehospital resuscitation.

The critical care literature 2018

An emergency physician (EP) is often the first health care provider to evaluate, resuscitate, and manage a critically ill patient. In recent years, the annual hours of critical care delivered in emergency departments (EDs) across the United States increased more than 200% (Herring et al., 2013). In addition to seeing more critically ill patients, EPs are often tasked with providing critical care long beyond the initial resuscitation period. In fact, more than 50% of ED patients that require admission to the intensive care unit (ICU) remain in the ED for more than 6 h (Rose et al., 2016). Longer ED boarding times for critically ill patients is associated with a negative impact on inpatient morbidity and mortality (Mathews et al., 2018). It is during these early hours of critical illness, while the patient is in the ED, where lives can be saved or lost. Therefore, it is important for the EP to be knowledgeable about recent developments in critical care medicine. This review summarizes important articles published in 2018 pertaining to the resuscitation and care of select critically ill patients. We chose these articles based on our opinion of the importance of the study findings and their application to clinical care in the ED. The following topics are covered: cardiac arrest, post-arrest care, septic shock, rapid sequence intubation, mechanical ventilation, fluid resuscitation, and metabolic acidosis.

Characteristics of Out of Hospital Cardiac Arrest in the United Arab Emirates

Background:

Out of hospital cardiac arrest is one of the leading causes of death globally. This study aimed to identify the characteristics of out of hospital cardiac arrest patients who were attended and treated by the National Ambulance crew. A lot of studies reported the importance of implementing chain of survival to increase survival rates from cardiac arrest. To be implemented in United Arab Emirates (UAE), it required a detailed study of the community engagement. The study aimed to explore the demography of the incidences, location, age, gender epidemiology of the patients who had their cardiac arrest witnessed along with their Bystander cardiopulmonary resuscitation (CPR) performed prior to the arrival of National Ambulance and public access to an automated external defibrillator. The return of spontaneous circulation was also explored prior to their arrival to the emergency department.

Methods:

The research is a prospective descriptive cohort study of out of hospital cardiac arrest patients attended by National Ambulance between July 2017 and June 2018. The National Ambulance provides emergency medical services for public and private hospitals in the Emirates of Sharjah, Ajman, Ras-al-Khaimah, Fujairah, and Umm Al-Quwain and its clients in Abu Dhabi in UAE. Data for the study were collected by the National Ambulance crew attending the OHCA patients, using a structured questionnaire.

Results:

In this 1-year period, a total of 715 out of hospital cardiac arrest cases were attended by the National Ambulance with higher percentage (77%) of male patients. Resuscitation and transportation were attempted for 95% whereas 5% were pronounced dead on the spot. In this study, the median age of the patients was 50 years. Majority of the patients were Asians 55% (n = 395) followed by Arabs non-UAE citizens 19.4% (n = 139) and UAE citizens 16% (n = 113). Patients facing sudden cardiac arrest in their homes or residences represented 69.9% (n = 500), street and public places 22.5% (n = 161), and workplace 6.8% (n = 49). The percentage of patients who had witnessed cardiac arrest was 51.7% (n = 370) only 197 had CPR performed on them prior to the arrival of National Ambulance. Low public access to AED was found in this population that is 1.8% (n = 13). A majority of the participants in this study had nonshockable rhythms 84.3% (n = 603) whereas shockable rhythms presented on 11% (n = 80). The percentage of patients who had ROSC at the scene or en route to the hospitals was found 9.2% (n = 66).

Conclusion:

In this 1-year study, the result showed that cardiac arrest was recognized and witnessed in about half of the cases, but low bystander CPR was performed. Low public access and use of AED were found. Data on hospitalized and discharged OHCA patients were not available and required further linkage and corporation between ambulance services and hospitals to ensure data continuity of OHCA cases. This study is essential for the implementation of proper chain of survival and reduction in mortality rates in UAE.

Vasopressors During Cardiopulmonary Resuscitation. A Network Meta-Analysis of Randomized Trials

OBJECTIVES

Several randomized controlled trials have compared adrenaline (epinephrine) with alternative therapies in patients with cardiac arrest with conflicting results. Recent observational studies suggest that adrenaline might increase return of spontaneous circulation but worsen neurologic outcome. We systematically compared all the vasopressors tested in randomized controlled trials in adult cardiac arrest patients in order to identify the treatment associated with the highest rate of return of spontaneous circulation, survival, and good neurologic outcome.

DESIGN

Network meta-analysis.

PATIENTS

Adult patients undergoing cardiopulmonary resuscitation.

INTERVENTIONS

PubMed, Embase, BioMed Central, and the Cochrane Central register were searched (up to April 1, 2017). We included all the randomized controlled trials comparing a vasopressor with any other therapy. A network meta-analysis with a frequentist approach was performed to identify the treatment associated with the highest likelihood of survival.

MEASUREMENTS AND MAIN RESULTS

Twenty-eight studies randomizing 14,848 patients in 12 treatment groups were included. Only a combined treatment with adrenaline, vasopressin, and methylprednisolone was associated with increased likelihood of return of spontaneous circulation and survival with a good neurologic outcome compared with several other comparators, including adrenaline. Adrenaline alone was not associated with any significant difference in mortality and good neurologic outcome compared with any other comparator.

CONCLUSIONS

In randomized controlled trials assessing vasopressors in adults with cardiac arrest, only a combination of adrenaline, vasopressin, and methylprednisolone was associated with improved survival with a good neurologic outcome compared with any other drug or placebo, particularly in in-hospital cardiac arrest. There was no significant randomized evidence to support neither discourage the use of adrenaline during cardiac arrest.

Epinephrine in cardiac arrest: The PARAMEDIC2 trial

Abstract Link:http://www.nejm.org/doi/10.1056/NEJMoa1806842

Full citation: Perkins GD, Ji C, Deakin CD, et al. A randomized trial of epinephrine in out-of-hospital cardiac arrest. N Engl J Med 2018; epub, NEJMoa1806842.

Article type: Therapy

Ratings: Methods – 4/5 Usefulness – 3.5/5

Epinephrine during resuscitation of traumatic cardiac arrest and increased mortality: a post hoc analysis of prospective observational study

Background

The beneficial effect of epinephrine during resuscitation from out-of-hospital cardiac arrest (OHCA) has been inconclusive, and potential harm has been suggested, particularly in trauma victims. Although no significant improvement in neurological outcomes has been found among resuscitated patients using epinephrine, including trauma patients, the use of epinephrine is recommended in the Advanced Trauma Life Support protocol. Given that the use of vasopressors was reported to be associated with increased mortality in patients with massive bleeding, the undesirable effects of epinephrine during the resuscitation of traumatic OHCA should be elucidated. We hypothesised that resuscitation with epinephrine would increase mortality in patients with OHCA following trauma.

Methods

This study is a post-hoc analysis of a prospective, multicentre, observational study on patients with OHCA between January 2012 and March 2013. We included adult patients with traumatic OHCA who were aged ≥15 years and excluded those with missing survival data. Patient data were divided into epinephrine or no-epinephrine groups based on the use of epinephrine during resuscitation at the hospital. Propensity scores were developed to estimate the probability of being assigned to the epinephrine group using multivariate logistic regression analyses adjusted for known survival predictors. The primary outcome was survival 7 days after injury, which was compared among the two groups after propensity score matching.

Results

Of the 1125 adults with traumatic OHCA during the study period, 1030 patients were included in this study. Among them, 822 (79.8%) were resuscitated using epinephrine, and 1.1% (9/822) in the epinephrine group and 5.3% (11/208) in the no-epinephrine group survived 7 days after injury. The use of epinephrine was significantly associated with decreased 7-day survival (odds ratio = 0.20; 95% CI = 0.08–0.48; P < 0.01), and this result was confirmed by propensity score-matching analysis, in which 178 matched pairs were examined (adjusted odds ratio = 0.11; 95% CI = 0.01–0.85; P = 0.02).

Conclusions

The relationship between the use of epinephrine during resuscitation and decreased 7-day survival was found in patients with OHCA following trauma, and the propensity score-matched analyses validated the results. Resuscitation without epinephrine in traumatic OHCA should be further studied in a randomised controlled trial.

Impact of epinephrine administration frequency in out-of-hospital cardiac arrest patients: a retrospective analysis in a tertiary hospital setting

Introduction

Epinephrine is recommended for patients with out-of-hospital cardiac arrest (OHCA). However, whether epinephrine improves or adversely affects OHCA outcomes is controversial.

Objectives

This study aims to determine whether the frequency of epinephrine administration impacts OHCA patient survival.

Methods

We conducted a retrospective analysis of OHCA cases registered in the Emergency Department at King Fahd University Hospital, Saudi Arabia between 2005 and 2015. The primary outcomes were mortality and survival rates until discharge. The impact of epinephrine administration timing and frequency on patient survival was analyzed.

Results

Data from 300 OHCA cases were analyzed. Among them, 66.3% were men, and the overall mean age of 50.4 ± 20.6 years. The overall survival rate until hospital discharge was 12%. There was no statistically significant difference between in gender, age, or time interval to the first epinephrine dose in the survival and non-survival groups. Only the number of epinephrine doses was related to the survival outcome.

Conclusion

Non-survivors received significantly more epinephrine doses compared with survivors. However, a causal relationship between OHCA patient survival and epinephrine dose and time cannot be confirmed. Further studies are needed to investigate whether the long-term outcomes in OHCA patients are influenced by the timing and frequency of epinephrine administration.

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.

Repeated adrenaline doses and survival from an out-of-hospital cardiac arrest

BACKGROUND

Adrenaline is the primary drug of choice for resuscitation from out-of-hospital cardiac arrest (OHCA). Although adrenaline may increase the chance of achieving return of spontaneous circulation (ROSC), there is limited evidence that repeated doses of adrenaline improves overall survival, and increasing evidence of a detrimental effect on neurological function in survivors. This paper reports the relationship between repeated doses of adrenaline and survival in a cohort of patients attended by the London Ambulance Service in the United Kingdom.

METHODS

A retrospective review of OHCA treated by the London Ambulance Service over a one year period. Patients aged ≥18 years who received one or more doses of adrenaline (1 mg bolus) during resuscitation were included in the analyses. Outcomes described are survival to hospital discharge and survival to one year post-arrest.

RESULTS

Over the one year study period, 3151 patients received adrenaline during OHCA. A significant inverse relationship was found between increasing cumulative doses of adrenaline and survival both to hospital discharge and one year post-arrest. No patients survived after receiving more than ten adrenaline doses.

CONCLUSION

Our study indicates that repeated doses of adrenaline are associated with decreasing odds of survival. There were no survivors amongst patients requiring more than 10 doses of adrenaline.

Adrenaline and vasopressin for cardiac arrest

BACKGROUND

Adrenaline and vasopressin are widely used to treat people with cardiac arrest, but there is uncertainty about the safety, effectiveness and the optimal dose.

OBJECTIVES

To determine whether adrenaline or vasopressin, or both, administered during cardiac arrest, afford any survival benefit.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase and DARE from their inception to 8 May 2018, and the International Liaison Committee on Resuscitation 2015 Advanced Life Support Consensus on Science and Treatment Recommendations. We also searched four trial registers on 5 September 2018 and checked the reference lists of the included studies and review papers to identify potential papers for review.

SELECTION CRITERIA

Any randomised controlled trial comparing: standard-dose adrenaline versus placebo; standard-dose adrenaline versus high-dose adrenaline; and adrenaline versus vasopressin, in any setting, due to any cause of cardiac arrest, in adults and children. There were no language restrictions.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified trials for review, assessed risks of bias and extracted data, resolving disagreements through re-examination of the trial reports and by discussion. We used risk ratios (RRs) with 95% confidence intervals (CIs) to compare dichotomous outcomes for clinical events. There were no continuous outcomes reported. We examined groups of trials for heterogeneity. We report the quality of evidence for each outcome, using the GRADE approach.

MAIN RESULTS

We included 26 studies (21,704 participants).Moderate-quality evidence found that adrenaline increased survival to hospital discharge compared to placebo (RR 1.44, 95% CI 1.11 to 1.86; 2 studies, 8538 participants; an increase from 23 to 32 per 1000, 95% CI 25 to 42). We are uncertain about survival to hospital discharge for high-dose compared to standard-dose adrenaline (RR 1.10, 95% CI 0.75 to 1.62; participants = 6274; studies = 10); an increase from 33 to 36 per 1000, 95% CI 24 to 53); standard-dose adrenaline versus vasopressin (RR 1.25, 95% CI 0.84 to 1.85; 6 studies; 2511 participants; an increase from 72 to 90 per 1000, 95% CI 60 to 133); and standard-dose adrenaline versus vasopressin plus adrenaline (RR 0.76, 95% CI 0.47 to 1.22; 3 studies; 3242 participants; a possible decrease from 24 to 18 per 1000, 95% CI 11 to 29), due to very low-quality evidence.Moderate-quality evidence found that adrenaline compared with placebo increased survival to hospital admission (RR 2.51, 95% CI 1.67 to 3.76; 2 studies, 8489 participants; an increase from 83 to 209 per 1000, 95% CI 139 to 313). We are uncertain about survival to hospital admission when comparing standard-dose with high-dose adrenaline, due to very low-quality evidence. Vasopressin may improve survival to hospital admission when compared with standard-dose adrenaline (RR 1.27, 95% CI 1.04 to 1.54; 3 studies, 1953 participants; low-quality evidence; an increase from 260 to 330 per 1000, 95% CI 270 to 400), and may make little or no difference when compared to standard-dose adrenaline plus vasopressin (RR 0.95, 95% CI 0.83 to 1.08; 3 studies; 3249 participants; low-quality evidence; a decrease from 218 to 207 per 1000 (95% CI 181 to 236).There was no evidence that adrenaline (any dose) or vasopressin improved neurological outcomes.The rate of return of spontaneous circulation (ROSC) was higher for standard-dose adrenaline versus placebo (RR 2.86, 95% CI 2.21 to 3.71; participants = 8663; studies = 3); moderate-quality evidence; an increase from 115 to 329 per 1000, 95% CI 254 to 427). We are uncertain about the effect on ROSC for the comparison of standard-dose versus high-dose adrenaline and standard-does adrenaline compared to vasopressin, due to very low-quality evidence. Standard-dose adrenaline may make little or no difference to ROSC when compared to standard-dose adrenaline plus vasopressin (RR 0.97, 95% CI 0.87 to 1.08; 3 studies, 3249 participants; low-quality evidence; a possible decrease from 299 to 290 per 1000, 95% CI 260 to 323).The source of funding was not stated in 11 of the 26 studies. The study drugs were provided by the manufacturer in four of the 26 studies, but neither drug represents a profitable commercial option. The other 11 studies were funded by organisations such as research foundations and government funding bodies.

AUTHORS' CONCLUSIONS

This review provides moderate-quality evidence that standard-dose adrenaline compared to placebo improves return of spontaneous circulation, survival to hospital admission and survival to hospital discharge, but low-quality evidence that it did not affect survival with a favourable neurological outcome. Very low -quality evidence found that high-dose adrenaline compared to standard-dose adrenaline improved return of spontaneous circulation and survival to admission. Vasopressin compared to standard dose adrenaline improved survival to admission but not return of spontaneous circulation, whilst the combination of adrenaline and vasopressin compared with adrenaline alone had no effect on these outcomes. Neither standard dose adrenaline, high-dose adrenaline,vasopressin nor a combination of adrenaline and vasopressin improved survival with a favourable neurological outcome. Many of these studies were conducted more than 20 years ago. Treatment has changed in recent years, so the findings from older studies may not reflect current practice.

Selective beta-blocker esmolol improves cerebral cortex microcirculation in a swine ventricular fibrillation model

OBJECTIVE

This study aimed to identify whether esmolol attenuates cerebral cortex microcirculation blood flow due to epinephrine in prolonged ventricular fibrillation (VF) and cardiopulmonary resuscitation (CPR), and may improve neurological prognosis.

METHODS

Male pigs were randomized into the esmolol+epinephrine group (group EE), the epinephrine group (group EP), and the normal saline group (group NS) (n = 8 each group). Untreated VF for 8 minutes was induced in pigs. After CPR for 2 minutes, group EE received esmolol (500 µg/kg)+epinephrine (20 µg/kg), group EP received epinephrine 20 µg/kg, and group NS received 5 mL normal saline. Then, a 120 J electric shock was delivered. If the return of spontaneous circulation (ROSC) failed, epinephrine (20 µg/kg) was repeated in group EP and EE, followed by another 2 minutes of CPR, a 150 J electric shock was delivered every 2 minutes until ROSC. Cerebral microcirculation images were obtained at 0.5, 6, 12, and 24 hours by cranial windows after ROSC. Cerebral performance category scores and neurological deficit scores (NDS) were calculated. The frontal cortices were harvested after the animals were euthanized.

RESULTS

The NDS, the perfused vessel density, and the microcirculatory flow index of group EE were better than other two groups. The morphology of endothelial cells in the group EE remained intact; however, it was destroyed in the group EP.

CONCLUSIONS

Administration of esmolol with epinephrine may alleviate the impairment of cerebral microcirculation blood flow caused by the administration of epinephrine in prolonged VF and thereby improves neurological outcomes in a swine model.

Drugs in Out-of-Hospital Cardiac Arrest

Managing out-of-hospital cardiac arrest involves unique challenges, including delays in the initiation of advanced interventions and a limited number of trained personnel on scene. Recent out-of-hospital randomized controlled trials, systematic reviews, and metaanalyses provide key insights into what interventions are best proven to positively impact patient outcomes from out-of-hospital cardiac arrest. We review the literature on medications used in out-of-hospital cardiac arrest and summarize evidence-based guidelines from the American Heart Association that form the basis for most emergency medical services cardiac arrest protocols across the United States.

A Randomized Trial of Epinephrine in Out-of-Hospital Cardiac Arrest

BACKGROUND

Concern about the use of epinephrine as a treatment for out-of-hospital cardiac arrest led the International Liaison Committee on Resuscitation to call for a placebo-controlled trial to determine whether the use of epinephrine is safe and effective in such patients.

METHODS

In a randomized, double-blind trial involving 8014 patients with out-of-hospital cardiac arrest in the United Kingdom, paramedics at five National Health Service ambulance services administered either parenteral epinephrine (4015 patients) or saline placebo (3999 patients), along with standard care. The primary outcome was the rate of survival at 30 days. Secondary outcomes included the rate of survival until hospital discharge with a favorable neurologic outcome, as indicated by a score of 3 or less on the modified Rankin scale (which ranges from 0 [no symptoms] to 6 [death]).

RESULTS

At 30 days, 130 patients (3.2%) in the epinephrine group and 94 (2.4%) in the placebo group were alive (unadjusted odds ratio for survival, 1.39; 95% confidence interval [CI], 1.06 to 1.82; P=0.02). There was no evidence of a significant difference in the proportion of patients who survived until hospital discharge with a favorable neurologic outcome (87 of 4007 patients [2.2%] vs. 74 of 3994 patients [1.9%]; unadjusted odds ratio, 1.18; 95% CI, 0.86 to 1.61). At the time of hospital discharge, severe neurologic impairment (a score of 4 or 5 on the modified Rankin scale) had occurred in more of the survivors in the epinephrine group than in the placebo group (39 of 126 patients [31.0%] vs. 16 of 90 patients [17.8%]).

CONCLUSIONS

In adults with out-of-hospital cardiac arrest, the use of epinephrine resulted in a significantly higher rate of 30-day survival than the use of placebo, but there was no significant between-group difference in the rate of a favorable neurologic outcome because more survivors had severe neurologic impairment in the epinephrine group. (Funded by the U.K. National Institute for Health Research and others; Current Controlled Trials number, ISRCTN73485024 .).

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.

The role of adrenaline in cardiopulmonary resuscitation

Adrenaline has been used in the treatment of cardiac arrest for many years. It increases the likelihood of return of spontaneous circulation (ROSC), but some studies have shown that it impairs cerebral microcirculatory flow. It is possible that better short-term survival comes at the cost of worse long-term outcomes. This narrative review summarises the rationale for using adrenaline, significant studies to date, and ongoing research.

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.

ILCOR Scientific Knowledge Gaps and Clinical Research Priorities for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care: A Consensus Statement

Despite significant advances in the field of resuscitation science, important knowledge gaps persist. Current guidelines for resuscitation are based on the International Liaison Committee on Resuscitation 2015 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations, which includes treatment recommendations supported by the available evidence. The writing group developed this consensus statement with the goal of focusing future research by addressing the knowledge gaps identified during and after the 2015 International Liaison Committee on Resuscitation evidence evaluation process. Key publications since the 2015 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations are referenced, along with known ongoing clinical trials that are likely to affect future guidelines.

No Benefit in Neurologic Outcomes of Survivors of Out-of-Hospital Cardiac Arrest with Mechanical Compression Device

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) is a major cause of death and morbidity in the United States. Quality cardiopulmonary resuscitation (CPR) has proven to be a key factor in improving survival. The aim of our study was to investigate the outcomes of OHCA when mechanical CPR (LUCAS 2 Chest Compression System™) was utilized compared to conventional CPR. Although controlled trials have not demonstrated a survival benefit to the routine use of mechanical CPR devices, there continues to be an interest for their use in OHCA.

METHODS

We conducted a retrospective observational study of OHCA comparing the outcomes of mechanical and manual chest compressions in a fire department based EMS system serving a population of 1.4 million residents. Mechanical CPR devices were geographically distributed on 11 of 33 paramedic ambulances. Data were collected over a 36-month period and outcomes were dichotomized based on utilization of mechanical CPR. The primary outcome measure was survival to hospital discharge with a cerebral performance category (CPC) score of 1 or 2.

RESULTS

This series had 3,469 OHCA reports, of which 2,999 had outcome data and met the inclusion criteria. Of these 2,236 received only manual CPR and 763 utilized a mechanical CPR device during the resuscitation. Return of spontaneous circulation (ROSC) was attained in 44% (334/763) of the mechanical CPR resuscitations and in 46% (1,020/2,236) of the standard manual CPR resuscitations (p = 0.32). Survival to hospital discharge was observed in 7% (52/763) of the mechanical CPR resuscitations and 9% (191/2,236) of the manual CPR group (p = 0.13). Discharge with a CPC score of 1 or 2 was observed in 4% (29/763) of the mechanical CPR resuscitation group and 6% (129/2,236) of the manual CPR group (p = 0.036).

CONCLUSIONS

In our study, use of the mechanical CPR device was associated with a poor neurologic outcome at hospital discharge. However, this difference was no longer evident after logistic regression adjusting for confounding variables. Resuscitation management following institution of mechanical CPR, specifically medication and airway management, may account for the poor outcome reported. Further investigation of resuscitation management when a mechanical CPR device is utilized is necessary to optimize survival benefit.