Probability of Return of Spontaneous Circulation as a Function of Timing of Vasopressor Administration in Out-of-Hospital Cardiac Arrest

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.

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.

Advanced airway management during adult cardiac arrest: A systematic review

AIM

To systematically review the literature on advanced airway management during adult cardiac arrest in order to inform the International Liaison Committee of Resuscitation (ILCOR) consensus on science and treatment recommendations.

METHODS

The review was performed according to PRISMA guidelines and registered on PROSPERO (CRD42018115556). We searched Medline, Embase, and Evidence-Based Medicine Reviews for controlled trials and observational studies published before October 30, 2018. The population included adult patients with cardiac arrest. Two investigators reviewed studies for relevance, extracted data, and assessed the risk of bias of individual studies.

RESULTS

We included 78 observational studies and 11 controlled trials. Most of the observational studies and all of the controlled trials only included patients with out-of-hospital cardiac arrest. The risk of bias for individual observational studies was overall assessed as critical or serious, with confounding and selection bias being the primary sources of bias. Three of the controlled trials, all published in 2018, were powered for clinical outcomes with two comparing a supraglottic airway to tracheal intubation and one comparing bag-mask ventilation to tracheal intubation. All three trials had some concerns regarding risk of bias primarily due to lack of blinding and variable adherence to the protocol. Clinical and methodological heterogeneity across studies, for both the observational studies and the controlled trials, precluded any meaningful meta-analyses.

CONCLUSIONS

We identified a large number of studies related to advanced airway management in adult cardiac arrest. Three recently published, large randomized trials in out-of-hospital cardiac arrest will help to inform future guidelines. Trials of advanced airway management during in-hospital cardiac arrest are lacking.

A mobile device application to reduce medication errors and time to drug delivery during simulated paediatric cardiopulmonary resuscitation: a multicentre, randomised, controlled, crossover trial

BACKGROUND

Vasoactive drug preparation for continuous infusion in children is both complex and time consuming and places the paediatric population at higher risk than adults for medication errors. We developed a mobile device application (app) as a step-by-step guide for the preparation to delivery of drugs requiring continuous infusion. The app has been previously tested during simulation-based resuscitations in a previous single-centre trial. In this trial, our aim was to assess this app in various hospital settings.

METHODS

We did a prospective, multicentre, randomised, controlled, crossover trial to compare this app with an internationally used drug-infusion-rates table for the preparation of continuous drug infusion during standardised, simulation-based, paediatric post-cardiac arrest scenarios using a high-fidelity manikin. The scenarios were split into two study periods to assess the two preparation methods consecutively, separated by a washout distraction manoeuvre. Nurses in six paediatric emergency centres in Switzerland were randomly assigned (1:1) to start the scenario with either the app or the infusion-rates table and then complete the scenario using the other preparation method. The primary endpoint was the proportion of participants committing a medication error, which was defined as a deviation from the correct weight dose of more than 10%, miscalculation of the infusion rate, misprogramming of the infusion pump, or the inability to calculate drug dosage without calculation and guidance help from the study team. The medication error proportions observed with both preparation methods were compared by pooling both study periods, with paired data analysed using the unconditional exact McNemar test for dependent groups with a two-sided α level of 0·05. We did sensitivity analyses to investigate the carryover effect. This trial is registered with ClinicalTrials.gov, number NCT03021122.

FINDINGS

From March 1 to Dec 31, 2017, we randomly assigned 128 nurses to start the scenario using the app (n=64) or the infusion-rates table (n=64). Among the 128 drug preparations associated with each of the two methods, 96 (75%, 95% CI 67-82) delivered using the infusion-rates table were associated with medication errors compared with nine (7%, 3-13) delivered using the mobile app. Medication errors were reduced by 68% (95% CI 59-76%; p<0·0001) with the app compared with the table, as was the mean time to drug preparation (difference 148·2 s [95% CI 124·2-172·1], a 45% reduction; p<0·0001) and mean time to drug delivery (168·5 s [146·1-190·8], a 40% reduction; p<0·0001). Hospital size and nurses' experience did not modify the intervention effect. We detected no carryover effect.

INTERPRETATION

Critically ill children are particularly vulnerable to medication errors. A mobile app designed to help paediatric drug preparation during resuscitation with the aim to significantly reduce the occurrence of medication errors, drug preparation time, and delivery time could have the potential to change paediatric clinical practice in the area of emergency medicine.

FUNDING

Swiss National Science Foundation.

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.

Association Between Prompt Defibrillation and Epinephrine Treatment With Long-Term Survival After In-Hospital Cardiac Arrest

BACKGROUND

Prior studies have reported higher in-hospital survival with prompt defibrillation and epinephrine treatment in patients with in-hospital cardiac arrest (IHCA). Whether this survival benefit persists after discharge is unknown.

METHODS

We linked data from a national IHCA registry with Medicare files and identified 36 961 patients ≥65 years of age with an IHCA at 517 hospitals between 2000 and 2011. Patients with IHCA caused by pulseless ventricular tachycardia or ventricular fibrillation were stratified by prompt (≤2 minutes) versus delayed (>2 minutes) defibrillation, whereas patients with IHCA caused by asystole or pulseless electric activity were stratified by prompt (≤5 minutes) versus delayed (>5 minutes) epinephrine treatment. The association between prompt treatment and long-term survival for each rhythm type was assessed with multivariable hierarchical modified Poisson regression models.

RESULTS

Of 8119 patients with an IHCA caused by ventricular tachycardia or ventricular fibrillation, the rate of 1-year survival was higher in those treated with prompt defibrillation than with delayed defibrillation (25.7% [1466 of 5714] versus 15.5% [373 of 2405]; adjusted relative risk [RR], 1.49; 95% confidence interval [CI] 1.32-1.69; P<0.0001). This survival advantage persisted at 3 years (19.1% versus 11.0%; adjusted RR, 1.45; 95% CI, 1.23-1.69; P<0.0001) and at 5 years (14.7% versus 7.9%; adjusted RR, 1.50; 95% CI, 1.22-1.83; P<0.0001). Of 28 842 patients with an IHCA caused by asystole/pulseless electric activity, the rate of 1-year survival with prompt epinephrine treatment was higher than with delayed treatment (5.4% [1341 of 24 885] versus 4.3% [168 of 3957]; adjusted RR, 1.20; 95% CI, 1.02-1.41; P=0.02), but this survival benefit was no longer present at 3 years (3.5% versus 2.9%; adjusted RR, 1.17; 95% CI, 0.95-1.45; P=0.15) and at 5 years (2.3% versus 1.9%; adjusted RR, 1.18; 95% CI, 0.88-1.58; P=0.27).

CONCLUSIONS

Prompt defibrillation for IHCA caused by ventricular tachycardia or ventricular fibrillation was associated with higher rates of long-term survival throughout 5 years of follow-up, whereas prompt epinephrine treatment for asystole/pulseless electric activity was associated with greater survival at 1 year but not at 3 or 5 years. By quantifying the greater survival associated with timely defibrillation and epinephrine administration, these findings provide important insights into the durability of survival benefits for 2 process-of-care measures in current resuscitation guidelines.

Neurological Favorable Outcomes Associated with EMS Compliance and On-Scene Resuscitation Time Protocol

PURPOSE

Korean national emergency care protocol for EMS providers recommends a minimum of 5 minutes of on-scene resuscitation before transport to hospital in cases of Out-of-Hospital Cardiac Arrest (OHCA). We compared survival outcome of OHCA patients according to scene time interval (STI)-protocol compliance of EMS.

METHODS

EMS treated adult OHCAs with presumed cardiac etiology during a two-year period were analyzed. Non-compliance was defined as hospital transport with STI less than 6 minutes without return of spontaneous circulation (ROSC) on scene. Propensity score for compliance with protocol was calculated and based on the calculated propensity score, 1:1 matching was performed between compliance and non-compliance group. Univariate analysis as well as multivariable logistic model was used to evaluate the effect of compliance to survival outcome.

RESULTS

Among a total of 28,100 OHCAs, EMS transported 7,026 (25.0%) cardiac arrests without ROSC on the scene with an STI less than 6 minutes. A total of 6,854 cases in each group were matched using propensity score matching. Overall survival to discharge rate did not differ in both groups (4.6% for compliance group vs. 4.5 for non-compliance group, p = 0.78). Adjusted odds ratio of compliance for survival to discharge were 1.12 (95% CI 0.92-1.36). More patients with favorable neurological outcome was shown in compliance group (2.5% vs. 1.7%, p < 0.01) and adjusted odds ratio was 1.91 (95% CI 1.42-2.59).

CONCLUSIONS

Although survival to discharge rate did not differ for patient with EMS non-compliance with STI protocol, lesser patients survived with favorable neurological outcomes when EMS did not stay for sufficient time on scene in OHCA before transport.

A Mobile Device App to Reduce Medication Errors and Time to Drug Delivery During Pediatric Cardiopulmonary Resuscitation: Study Protocol of a Multicenter Randomized Controlled Crossover Trial

BACKGROUND

During pediatric cardiopulmonary resuscitation (CPR), vasoactive drug preparation for continuous infusions is complex and time-consuming. The need for individual specific weight-based drug dose calculation and preparation places children at higher risk than adults for medication errors. Following an evidence-based and ergonomic driven approach, we developed a mobile device app called Pediatric Accurate Medication in Emergency Situations (PedAMINES), intended to guide caregivers step-by-step from preparation to delivery of drugs requiring continuous infusion. In a prior single center randomized controlled trial, medication errors were reduced from 70% to 0% by using PedAMINES when compared with conventional preparation methods.

OBJECTIVE

The purpose of this study is to determine whether the use of PedAMINES in both university and smaller hospitals reduces medication dosage errors (primary outcome), time to drug preparation (TDP), and time to drug delivery (TDD) (secondary outcomes) during pediatric CPR when compared with conventional preparation methods.

METHODS

This is a multicenter, prospective, randomized controlled crossover trial with 2 parallel groups comparing PedAMINES with a conventional and internationally used drug infusion rate table in the preparation of continuous drug infusion. The evaluation setting uses a simulation-based pediatric CPR cardiac arrest scenario with a high-fidelity manikin. The study involving 120 certified nurses (sample size) will take place in the resuscitation rooms of 3 tertiary pediatric emergency departments and 3 smaller hospitals. After epinephrine-induced return of spontaneous circulation, nurses will be asked to prepare a continuous infusion of dopamine using either PedAMINES (intervention group) or the infusion table (control group) and then prepare a continuous infusion of norepinephrine by crossing the procedure. The primary outcome is the medication dosage error rate. The secondary outcome is the time in seconds elapsed since the oral prescription by the physician to drug delivery by the nurse in each allocation group. TDD includes TDP. Stress level during the resuscitation scenario will be assessed for each participant by questionnaire and recorded by the heart rate monitor of a fitness watch. The study is formatted according to the Consolidated Standards of Reporting Trials Statement for Randomized Controlled Trials of Electronic and Mobile Health Applications and Online TeleHealth (CONSORT-EHEALTH) and the Reporting Guidelines for Health Care Simulation Research.

RESULTS

Enrollment and data analysis started in March 2017. We anticipate the intervention will be completed in late 2017, and study results will be submitted in early 2018 for publication expected in mid-2018. Results will be reported in line with recommendations from CONSORT-EHEALTH and the Reporting Guidelines for Health Care Simulation Research .

CONCLUSIONS

This paper describes the protocol used for a clinical trial assessing the impact of a mobile device app to reduce the rate of medication errors, time to drug preparation, and time to drug delivery during pediatric resuscitation. As research in this area is scarce, results generated from this study will be of great importance and might be sufficient to change and improve the pediatric emergency care practice.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03021122; https://clinicaltrials.gov/ct2/show/NCT03021122 (Archived by WebCite at http://www.webcitation.org/6nfVJ5b4R).

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.

A Mobile Device App to Reduce Time to Drug Delivery and Medication Errors During Simulated Pediatric Cardiopulmonary Resuscitation: A Randomized Controlled Trial

Background

During pediatric cardiopulmonary resuscitation (CPR), vasoactive drug preparation for continuous infusion is both complex and time-consuming, placing children at higher risk than adults for medication errors. Following an evidence-based ergonomic-driven approach, we developed a mobile device app called Pediatric Accurate Medication in Emergency Situations (PedAMINES), intended to guide caregivers step-by-step from preparation to delivery of drugs requiring continuous infusion.

Objective

The aim of our study was to determine whether the use of PedAMINES reduces drug preparation time (TDP) and time to delivery (TDD; primary outcome), as well as medication errors (secondary outcomes) when compared with conventional preparation methods.

Methods

The study was a randomized controlled crossover trial with 2 parallel groups comparing PedAMINES with a conventional and internationally used drugs infusion rate table in the preparation of continuous drug infusion. We used a simulation-based pediatric CPR cardiac arrest scenario with a high-fidelity manikin in the shock room of a tertiary care pediatric emergency department. After epinephrine-induced return of spontaneous circulation, pediatric emergency nurses were first asked to prepare a continuous infusion of dopamine, using either PedAMINES (intervention group) or the infusion table (control group), and second, a continuous infusion of norepinephrine by crossing the procedure. The primary outcome was the elapsed time in seconds, in each allocation group, from the oral prescription by the physician to TDD by the nurse. TDD included TDP. The secondary outcome was the medication dosage error rate during the sequence from drug preparation to drug injection.

Results

A total of 20 nurses were randomized into 2 groups. During the first study period, mean TDP while using PedAMINES and conventional preparation methods was 128.1 s (95% CI 102-154) and 308.1 s (95% CI 216-400), respectively (180 s reduction, P=.002). Mean TDD was 214 s (95% CI 171-256) and 391 s (95% CI 298-483), respectively (177.3 s reduction, P=.002). Medication errors were reduced from 70% to 0% (P<.001) by using PedAMINES when compared with conventional methods.

Conclusions

In this simulation-based study, PedAMINES dramatically reduced TDP, to delivery and the rate of medication errors.

Determinants of unfavorable prognosis for out-of-hospital sudden cardiac arrest in Bielsko-Biala district

INTRODUCTION

The prognosis in out-of-hospital sudden cardiac arrest (OHCA) remains unfavorable and depends on a number of demographic and clinical variables, the reversibility of its causes and its mechanisms.

AIM

To investigate the risk factors of prehospital death in patients with OHCA in Bielsko County.

MATERIAL AND METHODS

The study analyzed all dispatch cards of the National Emergency Medical Services (EMS) teams in Bielsko-Biala for the year 2013 (n = 23 400). Only the cards related to sudden cardiac arrest in adults were ultimately included in the study (n = 272; 190 men, 82 women; median age: 71 years).

RESULTS

Sixty-seven victims (45 men, 22 women) were pronounced dead upon the arrival of the EMS team, and cardiopulmonary resuscitation (CPR) was not undertaken. In the remaining group of 205 subjects, CPR was commenced but was ineffective in 141 patients (97 male, 44 female). Although univariate analysis indicated 6 predictors of prehospital death, including OHCA without the presence of witnesses (odds ratio (OR) = 4.2), OHCA occurring in a public place (OR = 3.1), no bystander CPR (OR = 9.7), no bystander cardiac massage (OR = 13.1), initial diagnosis of non-shockable cardiac rhythm (OR = 7.0), and the amount of drugs used for CPR (OR = 0.4), logistic regression confirmed that only the lack of bystander cardiac massage (OR = 6.5) and non-shockable rhythm (OR = 4.6) were independent determinants of prehospital death (area under ROC curve = 0.801).

CONCLUSIONS

Non-shockable rhythm of cardiac arrest and lack of bystander cardiac massage are independent determinants of prehospital death in Bielsko-Biala inhabitants suffering from OHCA.

Temporal Trends in Outcomes after Out-of-Hospital Cardiac Arrests Witnessed by Emergency Medical Services in Japan: A Population-Based Study

OBJECTIVE

Survival after out-of-hospital cardiac arrests (OHCA) witnessed by emergency medical service (EMS) personnel has been insufficiently understood. The aim of this study was to evaluate temporal trends in survival after EMS-witnessed OHCAs in Japan.

METHODS

A nationwide, population-based, observational cohort study of consecutive adult OHCA patients with emergency responder resuscitation attempts from January 2005 to December 2012 in Japan. We assessed the trends in annual incidence, characteristics, and outcomes of OHCA patients witnessed by EMS personnel. Multiple logistic regression analysis was used to assess factors that were potentially associated with neurologically favorable outcome defined as cerebral performance category scale 1or 2.

RESULTS

During the study period, a total of 66,760 EMS-witnessed OHCAs were documented. The annual incidence rates per 100,000 persons of EMS-witnessed OHCA patients increased from 4.6 (n = 7219) in 2005 to 4.9 (n = 9256) in 2012 (p for trend = 0.035). The proportion of one-month survival with neurologically favorable outcome improved from 5.9% in 2005 to 8.6% in 2012 (p for trend < 0.001), and the proportion increased from 22.1% in 2005 to 30.2% in 2012 in cases with shockable rhythm (p for trend < 0.001). In a multivariate analysis, adults, male gender, shockable rhythm, presumed cardiac origin, and year were associated with a better neurological outcome.

CONCLUSIONS

In this population, the proportion of one-month survival with neurologically favorable outcome among OHCA patients witnessed by EMS personnel significantly improved during the study period.

Blinded Evaluation of Combination Drug Therapy for Prolonged Ventricular Fibrillation Using a Swine Model of Sudden Cardiac Arrest

Despite experimental evidence supporting the use of resuscitation drugs in the treatment of sudden cardiac arrest (CA), there are no good human clinical data to support the decades-old practice of giving these medications during out-of-hospital CA resuscitation. We hypothesized that the lack of efficacy in clinical practice in ventricular fibrillation (VF) is the failure-based manner in which resuscitation drugs have historically been administered (one at a time interspersed with chest compressions and a defibrillation attempt, giving the next only if the previous one was ineffective). The aim of this study was to determine if giving and circulating a combination of commonly available, historically used resuscitation drugs together, prior to the first defibrillation attempt after prolonged VF, might improve short-term outcomes compared with the failure-based serial drug approach used in the past. We used a well-established swine model of sudden prolonged untreated VF. Animals were randomized to receive epinephrine (0.01 mg/kg), vasopressin (0.5 U/kg), amiodarone (4 mg/kg), and sodium bicarbonate (1.0 mEq/kg) in series (SERIES group [n = 53]) or a combination of epinephrine (0.01 mg/kg), vasopressin (0.5 U/kg), amiodarone (4 mg/kg), sodium bicarbonate (1.0 mEq/kg), and metoprolol (0.2 mg/kg) (COCKTAIL group) delivered in rapid succession at the beginning of the attempted resuscitation (n = 27). Data were analyzed descriptively. Baseline characteristics and chemistries between the two groups were the same. Termination of VF was statistically similar in the two groups: 88.7% (47/53) versus 85.2% (23/27) p = 0.66, with an adjusted relative risk ratio (RRR) of 0.94 (0.37, 1.15). However, ROSC was higher in the SERIES group (56.6% [30/53] versus 22.2% [6/27], adjusted RRR = 2.83; [1.16, 3.84] p = 0.029) as was 20-minute survival (52.8% [28/53] versus 18.5% [5/27], adjusted RRR = 3.15 [1.14, 4.54] p = 0.032). The combination of drugs studied, at these dosages, inexplicably worsened short-term outcomes after prolonged untreated VF.