The use of antiarrhythmic drugs for adult cardiac arrest: a systematic review

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.

Receiving Hospital Characteristics Associated With Survival in Patients Transported by Emergency Medical Services After Out-of-hospital Cardiac Arrest

OBJECTIVE

To test whether primary emergency medical services (EMS) transport to hospitals with certain characteristics (24/7 percutaneous coronary intervention [PCI] availability, trauma center status, large [>24 bed] intensive care unit [ICU]) versus hospitals without those characteristics is associated with improved hospital survival after out-of-hospital cardiac arrest (OHCA).

METHODS

This is an analysis of a prospectively collected EMS database, which archives patients with OHCA treated by a single large metropolitan EMS system. The database contains Utstein data, EMS transport data, and survival to hospital discharge. EMS providers uniformly apply advanced cardiac life support protocols to OHCA patients in the field. Patients with return of spontaneous circulation (ROSC) are transported to one of 10 hospitals in the area. If ROSC is not achieved within 30 minutes, efforts are terminated and the patient is not transported. We used multivariate logistic regression to test if receiving hospital characteristics were independently associated with survival among those transported after ROSC. We excluded patients not transported to a hospital and patients with incomplete outcome data.

RESULTS

Between January 2011 and December 2014, a total of 1,188 OHCA patients were resuscitated in the field and transported to an area hospital. After patients with missing data were excluded, 1,024 patients were included in the analysis. The mean (±SD) age was 61.1 (±17.0) years, and 57.7% were male. Of transported patients, 76% were taken to 24/7 PCI centers, 46% were taken to trauma centers, and 37% were taken to hospitals with large ICUs. There was considerable overlap in these hospital characteristics. A multivariate logistic regression model including age, sex, shockable rhythm, EMS time to scene, and dispatch complaint of cardiac arrest found that none of the hospital characteristics were independently associated with increased survival to discharge. The odds ratios (95% confidence intervals) for survival were as follows: PCI center, 1.28 (0.80 to 2.04); trauma center, 1.44 (0.73 to 2.85); and large ICU, 1.39 (0.69 to 2.80).

CONCLUSIONS

After adjusting for patient demographic data, we found no significant independent association between receiving hospital characteristics and survival to discharge among OHCA patients transported after ROSC by a single EMS agency.

Amiodarone and cardiac arrest: Systematic review and meta-analysis

INTRODUCTION

The 2015 Guidelines for Resuscitation recommend amiodarone as the antiarrhythmic drug of choice in the treatment of resistant ventricular fibrillation or pulseless ventricular tachycardia. We reviewed the effects of amiodarone on survival and neurological outcome after cardiac arrest.

METHODS

We systematically searched MEDLINE and Cochrane Library from 1940 to March 2016 without language restrictions. Randomized control trials (RCTs) and observational studies were selected.

RESULTS

Our search initially identified 1663 studies, 1458 from MEDLINE and 205 from Cochrane Library. Of them, 4 randomized controlled studies and 6 observational studies met the inclusion criteria and were selected for further review. Three randomized studies were included in the meta-analysis. Amiodarone significantly improves survival to hospital admission (OR=1.402, 95% CI: 1.068-1.840, Z=2.43, P=0.015), but neither survival to hospital discharge (RR=0.850, 95% CI: 0.631-1.144, Z=1.07, P=0.284) nor neurological outcome compared to placebo or nifekalant (OR=1.114, 95% CI: 0.923-1.345, Z=1.12, P=0.475).

CONCLUSIONS

Amiodarone significantly improves survival to hospital admission. However there is no benefit of amiodarone in survival to discharge or neurological outcomes compared to placebo or other antiarrhythmics.

Year in review 2013: Critical Care--out-of-hospital cardiac arrest, traumatic injury, and other emergency care conditions

In this review, we discuss articles published in 2013 contributing to the existing literature on the management of out-of-hospital cardiac arrest and the evaluation and management of several other emergency conditions, including traumatic injury. The utility of intravenous medications, including epinephrine and amiodarone, in the management of cardiac arrest is questioned, as are cardiac arrest termination-of-resuscitation rules. Articles discussing mode of transportation in trauma are evaluated, and novel strategies for outcome prediction in traumatic injury are proposed. Diagnostic strategies, including computerized tomography scan for the diagnosis of smoke inhalation injury and serum biomarkers for the diagnosis of post-cardiac arrest syndrome and acute aortic dissection, are also explored. Although many of the articles discussed raise more questions than they answer, they nevertheless provide ample opportunity for further investigation.

Resuscitation with amiodarone increases survival after hemorrhage and ventricular fibrillation in pigs

Supplemental digital content is available in the text.

BACKGROUND

The aim of this experimental study was to compare survival and hemodynamic effects of a low-dose amiodarone and vasopressin compared with vasopressin in hypovolemic cardiac arrest model in piglets.

METHODS

Eighteen anesthetized male piglets (with a weight of 25.3 [1.8] kg) were bled approximately 30% of the total blood volume via the femoral artery to a mean arterial blood pressure of 35 mm Hg in a 15-minute period. Afterward, the piglets were subjected to 4 minutes of untreated ventricular fibrillation followed by 11 minutes of open-chest cardiopulmonary resuscitation. At 5 minutes, circulatory arrest amiodarone 1 mg/kg was intravenously administered in the amiodarone group (n = 9), while the control group received the same amount of saline (n = 9). At the same time, all piglets received vasopressin 0.4 U/kg intravenously administered and hypertonic-hyperoncotic solution 3-mL/kg infusion for 20 minutes. Internal defibrillation was attempted from 7 minutes of cardiac arrest to achieve restoration of spontaneous circulation. The experiment was terminated 3 hours after resuscitation.

RESULTS

Three-hour survival was greater in the amiodarone group (p = 0.02). After the successful resuscitation, the amiodarone group piglets had significantly lower heart rate as well as greater systolic, diastolic, and mean arterial pressure. Troponin I plasma concentrations were lower and urine output was greater in the amiodarone group.

CONCLUSION

Combined resuscitation with amiodarone and vasopressin after hemorrhagic circulatory arrest resulted in greater 3-hour survival, better preserved hemodynamic parameters, and smaller myocardial injury compared with resuscitation with vasopressin only.

Duration of resuscitation efforts and functional outcome after out-of-hospital cardiac arrest: when should we change to novel therapies?

BACKGROUND

Functionally favorable survival remains low after out-of-hospital cardiac arrest. When initial interventions fail to achieve the return of spontaneous circulation, they are repeated with little incremental benefit. Patients without rapid return of spontaneous circulation do not typically survive with good functional outcome. Novel approaches to out-of-hospital cardiac arrest have yielded functionally favorable survival in patients for whom traditional measures had failed, but the optimal transition point from traditional measures to novel therapies is ill defined. Our objective was to estimate the dynamic probability of survival and functional recovery as a function of resuscitation effort duration to identify this transition point.

METHODS AND RESULTS

Retrospective cohort study of a cardiac arrest database at a single site. We included 1014 adult (≥18 years) patients experiencing nontraumatic out-of-hospital cardiac arrest between 2005 and 2011, defined as receiving cardiopulmonary resuscitation or defibrillation from a professional provider. We stratified by functional outcome at hospital discharge (modified Rankin scale). Survival to hospital discharge was 11%, but only 6% had a modified Rankin scale of 0 to 3. Within 16.1 minutes of cardiopulmonary resuscitation, 89.7% (95% confidence interval, 80.3%-95.8%) of patients with good functional outcome had achieved return of spontaneous circulation, and the probability of good functional recovery fell to 1%. Adjusting for prehospital and inpatient covariates, cardiopulmonary resuscitation duration (minutes) is independently associated with favorable functional status at hospital discharge (odds ratio, 0.84; 95% confidence interval, 0.72-0.98; P=0.02).

CONCLUSIONS

The probability of survival to hospital discharge with a modified Rankin scale of 0 to 3 declines rapidly with each minute of cardiopulmonary resuscitation. Novel strategies should be tested early after cardiac arrest rather than after the complete failure of traditional measures.

Early coronary revascularization improves 24h survival and neurological function after ischemic cardiac arrest. A randomized animal study

BACKGROUND

Survival after out-of-hospital cardiac arrest (OHCA) remains poor. Acute coronary obstruction is a major cause of OHCA. We hypothesize that early coronary reperfusion will improve 24h-survival and neurological outcomes.

METHODS

Total occlusion of the mid LAD was induced by balloon inflation in 27 pigs. After 5min, VF was induced and left untreated for 8min. If return of spontaneous circulation (ROSC) was achieved within 15min (21/27 animals) of cardiopulmonary resuscitation (CPR), animals were randomized to a total of either 45min (group A) or 4h (group B) of LAD occlusion. Animals without ROSC after 15min of CPR were classified as refractory VF (group C). In those pigs, CPR was continued up to 45min of total LAD occlusion at which point reperfusion was achieved. CPR was continued until ROSC or another 10min of CPR had been performed. Primary endpoints for groups A and B were 24-h survival and cerebral performance category (CPC). Primary endpoint for group C was ROSC before or after reperfusion.

RESULTS

Early compared to late reperfusion improved survival (10/11 versus 4/10, p=0.02), mean CPC (1.4±0.7 versus 2.5±0.6, p=0.017), LVEF (43±13 versus 32±9%, p=0.01), troponin I (37±28 versus 99±12, p=0.005) and CK-MB (11±4 versus 20.1±5, p=0.031) at 24-h after ROSC. ROSC was achieved in 4/6 animals only after reperfusion in group C.

CONCLUSIONS

Early reperfusion after ischemic cardiac arrest improved 24h survival rate and neurological function. In animals with refractory VF, reperfusion was necessary to achieve ROSC.

Low doses of intravenous epinephrine for refractory sustained monomorphic ventricular tachycardia

We report three cases of sustained monomorphic ventricular tachycardia (VT) in the setting of coronary artery disease, resistant to beta-blockers in two patients and to amiodarone in all, successfully terminated by low doses of intravenous (IV) epinephrine. VT was the first manifestation of coronary artery disease in one patient, whereas the other two patients had a previous history of myocardial infarction and were recipients of an implantable cardioverter-defibrillator (ICD). One of these two patients experienced an arrhythmic storm. All had hemodynamic instability at the time of epinephrine administration. A single slow administration of IV epinephrine (0.5 to 1 mg administered over 30 to 60 s) restored sinus rhythm after 30-90 s with only minor side effects. In the ICD patient with recurrent VT and several cardioversions due to transformation of VT to ventricular fibrillation, epinephrine injection led to the avoidance of further shocks. Although potentially harmful, low doses of IV epinephrine used alone or in combination with beta-blocker treatment and electrical cardioversion may be an alternative effective therapy for sustained monomorphic VT refractory to amiodarone. The role of epinephrine in the termination of VT should be studied further, especially in patients pre-treated with amiodarone in combination with beta-blockers.

RECOVER evidence and knowledge gap analysis on veterinary CPR. Part 7: Clinical guidelines

OBJECTIVE

To present a series of evidence-based, consensus guidelines for veterinary CPR in dogs and cats.

DESIGN

Standardized, systematic evaluation of the literature, categorization of relevant articles according to level of evidence and quality, and development of consensus on conclusions for application of the concepts to clinical practice. Questions in five domains were examined: Preparedness and Prevention, Basic Life Support, Advanced Life Support, Monitoring, and Post-Cardiac Arrest Care. Standardized worksheet templates were used for each question, and the results reviewed by the domain members, by the RECOVER committee, and opened for comments by veterinary professionals for 4 weeks. Clinical guidelines were devised from these findings and again reviewed and commented on by the different entities within RECOVER as well as by veterinary professionals.

SETTING

Academia, referral practice and general practice.

RESULTS

A total of 74 worksheets were prepared to evaluate questions across the five domains. A series of 101 individual clinical guidelines were generated. In addition, a CPR algorithm, resuscitation drug-dosing scheme, and postcardiac arrest care algorithm were developed.

CONCLUSIONS

Although many knowledge gaps were identified, specific clinical guidelines for small animal veterinary CPR were generated from this evidence-based process. Future work is needed to objectively evaluate the effects of these new clinical guidelines on CPR outcome, and to address the knowledge gaps identified through this process.