Effects of prehospital adrenaline administration on out-of-hospital cardiac arrest outcomes: a systematic review and meta-analysis

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

Background and Aims

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

Methods

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

Results

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

Conclusion

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

Trauma Anesthesiology Perioperative Management Update

Anesthesia for patients with life-threatening injuries is an essential part of post-accident care. Unfortunately, there is variability in trauma anesthesia care and numerous nonstandardized methods of working with patients remain. Uncertainty exists as to when and how best to intubate trauma patients, the use of vasopressors, and the appropriate management of severe traumatic brain injury. Some physicians recommend prehospital rapid sequence intubation, whereas others use bag-mask ventilation at lower pressures with no cricoid pressure and early transport to a trauma center. Overall, the absence of uniformity in trauma anesthesia care underlines the need for continued study and dialogue to define best practices and optimize patient outcomes.

Comparing the clinical and economic efficiency of four natural surfactants in treating infants with respiratory distress syndrome

Surfactant therapy has revolutionized the treatment of respiratory distress syndrome (RDS) over the past few decades. Relying on a new method, the current research seeks to compare four common surfactants in the health market of Iran to determine the best surfactant according to the selected criteria. The research was a cross-sectional, retrospective study that used the data of 13,169 infants as recorded on the information system of the Iranian Ministry of Health. To rank the surfactants used, the following indicators were measured: re-dosing rate, average direct treatment cost, average length of stay, disease burden, need for invasive mechanical ventilation, survival at discharge, and medical referrals. The CRITIC (criteria importance through intercriteria correlation) method was used to determine the weight of the indicators, and MABAC (multi-attributive border approximation area comparison) was used to prioritize the surfactants. Based on the seven selected indicators in this research (re-dosing rate, average length of stay, direct medical cost per one prescription, medical referral rate, survival at discharge, disability-adjusted life years, number of newborns in need of invasive mechanical ventilation) and using multi-criteria analysis method, Alveofact was identified as the worst surfactant in infants with either more or less than 32 weeks' gestation. So that some criteria were worse in Alveofact group infants than other groups; for example, in the comparison of the Alveofact group with the average of the total population, it was found that the survival rate at discharge was 57.14% versus 66.43%, and the rate of re-dosing was 1.63 versus 1.39. BLES (bovine lipid extract surfactant) was the best alternative for infants more than 32 weeks' gestation, whereas Survanta was identified as best option for infants with less than 32 weeks' gestation. Curosurf showed an average level of functionality in the ranking. This study advises the policy makers in the field of neonatal health to increase the market share of more effective surfactants based on this study and other similar studies. On the other hand, neonatal health care providers are also advised to prioritize the use of more effective surfactants if possible, depending on the clinical conditions and desired improvements.

Outcomes of Cardiopulmonary Resuscitation and Predictors of Its Outcomes in the Emergency Department in King Saud Medical City, Saudi Arabia

BACKGROUND

Cardiac arrest is a medical emergency marked by the cessation of cardiac mechanical activity and insufficient blood flow. CPR (cardiopulmonary resuscitation) is a life-saving method that involves restoring the essential functions of two vital organs: the heart and lungs. This study was conducted to identify the outcome of CPR in cardiac arrest patients presented to the emergency department (ED) and to identify predictors of CPR outcomes.

METHODOLOGY

This was a retrospective, descriptive study. All in-hospital cardiac arrest patients who underwent CPR in the King Saud Medical City (KSMC) ED between January 2017 and January 2020 were analyzed, with a sample size of 351 patients.

RESULTS

Overall return of spontaneous circulation (ROSC) and survival to discharge (STD) were achieved in 106 (30.2%) and 40 (11.39%) patients, respectively. When assessing the predictors of ROSC, the analyses showed that patient age, pre-arrest intubation, the method used to deliver oxygen, and CPR duration were all statistically significant predictors for ROSC. Similarly, when assessing predictors associated with STD, the analyses showed that patient age, pre-arrest intubation, the method used to deliver oxygen, and CPR duration were positively associated with STD.

CONCLUSION

Comparing the study's findings to those of similar studies, it shows a CPR outcome rate within the range of similar studies. It also highlights that CPR outcomes are highly associated with CPR duration (a maximum of 30 minutes), younger age, and endotracheal intubation.

Resuscitation with epinephrine worsens cerebral capillary no-reflow after experimental pediatric cardiac arrest: An in vivo multiphoton microscopy evaluation

Epinephrine is the principal resuscitation therapy for pediatric cardiac arrest (CA). Clinical data suggest that although epinephrine increases the rate of resuscitation, it fails to improve neurological outcome, possibly secondary to reductions in microvascular flow. We characterized the effect of epinephrine vs. placebo administered at resuscitation from pediatric asphyxial CA on microvascular and macrovascular cortical perfusion assessed using in vivo multiphoton microscopy and laser speckle flowmetry, respectively, and on brain tissue oxygenation (PbO₂), behavioral outcomes, and neuropathology in 16-18-day-old rats. Epinephrine-treated rats had a more rapid return of spontaneous circulation and brisk immediate cortical reperfusion during 1-3 min post-CA vs. placebo. However, at the microvascular level, epinephrine-treated rats had penetrating arteriole constriction and increases in both capillary stalling (no-reflow) and cortical capillary transit time 30-60 min post-CA vs. placebo. Placebo-treated rats had increased capillary diameters post-CA. The cortex was hypoxic post-CA in both groups. Epinephrine treatment worsened reference memory performance vs. shams. Hippocampal neuron counts did not differ between groups. Resuscitation with epinephrine enhanced immediate reperfusion but produced microvascular alterations during the first hour post-resuscitation, characterized by vasoconstriction, capillary stasis, prolonged cortical transit time, and absence of compensatory cortical vasodilation. Targeted therapies mitigating the deleterious microvascular effects of epinephrine are needed.

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.

Can We Predict Good Survival Outcomes by Classifying Initial and Re-Arrest Rhythm Change Patterns in Out-of-Hospital Cardiac Arrest Settings?

Objective

The purpose of this study was to investigate whether a change in prehospital arrest rhythms could allow medical personnel to predict survival outcomes in patients who achieved a return of spontaneous circulation (ROSC) in the setting of out-of-hospital cardiac arrest (OHCA).

Methods

The design of this study was retrospective, multi-regional, observational, and cross-sectional with a determining period between August 2015 and July 2016. Cardiac arrest rhythms were defined as a shockable rhythm (S), which refers to ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT), and non-shockable rhythm (NS), which refers to pulseless electrical activity or asystole. Survival to admission, survival to discharge, and good cerebral performance category (CPC) (CPC 1 or 2) were defined as good survival outcomes.

Results

A total of 163 subjects were classified into four groups according to the rhythm change pattern: NS→NS (98), S→S (27), S→NS (23), and NS→S (15). NS→NS pattern was used as the reference in logistic regression analysis. In the case of survival to hospital admission, the odds ratio (OR) (95% CI) of the S→S pattern was the highest [12.63 (3.56-44.85), p: <0.001 by no correction] and [7.29 (1.96-27.10), p = 0.003 with adjusting]. In the case of survival to hospital discharge, the OR (95% CI) of the S→S pattern was the highest [37.14 (11.71-117.78), p: <0.001 by no correction] and [13.85 (3.69-51.97), p: <0.001 with adjusting]. In the case of good CPC (CPC 1 or 2) at discharge, the OR (95% CI) of the S→S pattern was the highest [96 (19.14-481.60), p: <0.001 by no correction] and [149.69 (19.51-1148.48), p: <0.001 with adjusting].

Conclusions

The S→S group showed the highest correlation with survival to hospital admission, survival to hospital discharge, and good CPC (CPC 1 or 2) at discharge compared to the NS→NS group. Verifying changes in initial cardiac arrest rhythm and prehospital re-arrest (RA) rhythm patterns after prehospital ROSC can help us predict good survival outcomes in the OHCA setting.

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.

Frequency of Medical Reversal Among Published Randomized Controlled Trials Assessing Cardiopulmonary Resuscitation (CPR)

OBJECTIVE

To characterize what proportion of all randomized controlled trials (RCTs) among patients experiencing cardiac arrest find that an established practice is ineffective or harmful, that is, a medical reversal.

METHODS

We reviewed a database of all published RCTs of cardiac arrest patient populations between 1995 and 2014. Articles were classified on the basis of whether they tested a new or existing therapy and whether results were positive or negative. A reversal was defined as a negative RCT of an established practice. Further review and categorization were performed to confirm that reversals were supported by subsequent systematic review, as well as to identify the type of medical practice studied in each reversal. This study was conducted from October 2017 to June 17, 2019.

RESULTS

We reviewed 92 original articles, 76 of which could be conclusively categorized. Of these, 18 (24%) articles examined a new medical practice, whereas 58 (76%) tested an established practice. A total of 18 (24%) studies had positive findings, whereas 58 (76%) reached a negative conclusion. Of the 58 articles testing existing standard of care, 44 (76%) reversed that practice, whereas 14 (24%) reaffirmed it.

CONCLUSION

Reversal of cardiopulmonary resuscitation practices is widespread. This investigation sheds new light on low-value practices and patterns of medical research and suggests that novel resuscitation practices have low pretest probability and should be empirically tested with rigorous trials before implementation.

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.

Effects of epinephrine for out-of-hospital cardiac arrest: A systematic review and meta-analysis of randomized controlled trials

AIM

Our objective is to assess the effects of epinephrine for out of hospital cardiac arrest.

BACKGROUND

Cardiac arrest was the most serious medical incidents with an estimated incidence in the United States of 95.7 per 100,000 person years. Though epinephrine improved coronary and cerebral perfusion, improving a return of spontaneous circulation, potentially harmful effects on the heart lead to greater myocardial oxygen demand. Concerns about the effect of epinephrine for out-of-hospital cardiac arrest were controversial and called for a higher argument to determine whether the effects of epinephrine is safe and effective for shor and long terms outcomes.

METHOD

Searching databases consist of all kinds of searching tools, such as Medline, the Cochrane Library, Embase, PubMed, etc. All the included studies should meet our demand of this meta-analysis. In the all interest outcomes blow we take the full advantage of STATA to assess, the main measure is Risk Ratio (RR) with 95% confidence, the publication bias are assessed by Egger Test.

RESULT

In current systematic review and meta-analysis of randomized trials investigating epinephrine for out of hospital cardiac arrest, we found that epinephrine was associated with a significantly higher likelihood of ROSC (RR = 3.05, I = 23.1%, P = .0001) and survival to hospital discharge (RR = 1.40, I = 36.3%, P = .008) compared with non-adrenaline administration. Conversely, epinephrine did not increase CPC 1 or 2 (RR = 1.15, I = 40.5%, P = .340) and hospital admission (RR = 2.07, I = 88.2%, P = .0001).

CONCLUSION

In conclusion, in this systematic review and meta-analysis involving studies, the use of epinephrine resulted in a significantly higher likelihood of survival to hospital discharge and ROSC than the non-epinephrine administration, but, there was no significant between group difference in the rate of a favorable neurologic outcome.

The Effect of Prehospital Epinephrine in Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis

INTRODUCTION

Epinephrine has been recommended for out-of-hospital cardiac arrest (OHCA) resuscitation for nearly one century, but its efficacy and safety remain unclear in the literature. The primary aim of this review was to determine whether epinephrine increases the return of spontaneous circulation in OHCA patients.

METHODS

A systematic review and meta-analysis were conducted using the following databases: MEDLINE, EMBASE, and CENTRAL, from their inception until October 2018. All the randomized controlled trials (RCTs) were included. Observational studies, case reports, case series, and non-systematic reviews were excluded.

RESULTS

Two trials including 8,548 patients were eligible for inclusion in the data synthesis. In patients who received epinephrine during OHCA, the incidence of return of spontaneous circulation was increased, with an odds ratio (95%CI) of 4.25 (3.79-4.75), P <.001, high-quality of evidence. The number of patients transported to hospital was increased in patients who had prehospital epinephrine, with an odds ratio (95%CI) of 2.31 (2.11-2.53), P <.001, high-quality of evidence. The prehospital use of epinephrine was associated with an increased survival to hospital discharge, the odds ratio (95%CI) being 1.43 (1.10-1.87), P = .008, moderate-quality of evidence. No significant effect was noted on the favorable neurologic state of patient at hospital discharge, with an odds ratio (95%CI) of 1.21 (0.90-1.64), P = .21, moderate-quality of evidence.

CONCLUSIONS

This meta-analysis suggests that the prehospital use of epinephrine increases return of spontaneous circulation, transport of patients to hospital, and survival to hospital discharge for OHCA. However, no significant effects on favorable neurologic function at hospital discharge were demonstrated. The general quality of evidence ranged from moderate to high.

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.

Levels of Catecholamines in the Plasma of Patients with Cardiopulmonary Arrest

So far, there remains a controversy regarding the efficacy of epinephrine (Ep) in patients with cardiopulmonary arrest (CPA). In this study, we evaluated the importance of the plasma levels of catecholamines prior to the administration of Ep in patients with CPA. Patients with out-of-hospital cardiac arrest (OHCA) who were transferred to Gunma University Hospital were enrolled prospectively between July 2014 and July 2017. The levels of catecholamines [Ep, norepinephrine (NEp), and dopamine] and vasopressin (antidiuretic hormone) in the plasma were measured using blood samples of cardiogenic patients with OHCA not treated with Ep. Patients were divided into two groups: the return of spontaneous circulation [ROSC (+) ] group and the no return of spontaneous circulation [ROSC (-) ] group. The plasma levels of these agents and the conditions of resuscitation were compared between these two groups. 48 patients with cardiogenic CPA had not been treated with Ep prior to obtaining the blood samples. The ROSC (+) and ROSC (-) groups included 14 and 34 patients, respectively. The frequency of prehospital defibrillation was significantly higher in the ROSC (+) group. However, the prehospital resuscitation time was significantly shorter in the ROSC (+) group. Moreover, the levels of Ep and NEp in the plasma were significantly lower in the ROSC (+) group. The increased levels of Ep in the plasma may not be associated with the acquisition of ROSC in patients with cardiogenic CPA.

Epinephrine for out of hospital cardiac arrest: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the effectiveness of epinephrine, compared with control treatments, on survival at admission, ROSC, survival at discharge, and a favorable neurologic outcome in adult patients during OHCA.

DATA SOURCE

MEDLINE and PubMed from inception to August 2018.

STUDY SELECTION

Randomized controlled trials (RCTs) on adult patients after OHCA treated with epinephrine versus controls.

DATA EXTRACTION

Independent, double-data extraction; risk of bias assessment with Cochrane Collaboration's criteria.

DATA SYNTHESIS

15 RCTs representing 20 716 OHCA adult patients. Epinephrine, compared with all pooled treatments, was associated with a better survival rate to hospital discharge (RR: 1.16, 95% CI: 1.00-1.35) and a favorable neurologic outcome (RR: 1.24, 95% CI: 1.04-1.48). No difference was found in survival to hospital admission (RR: 1.02, 95% CI: 0.75-1.38) and ROSC when comparing epinephrine with all pooled treatments (RR: 1.13, 95% CI: 0.84-1.53). When epinephrine was compared with a placebo/no drugs, survival to hospital discharge (RR: 1.34, 95% CI: 1.08-1.67), ROSC (RR: 2.03, 95% CI: 1.18-3.51) and survival to hospital admission (RR: 2.04, 95% CI: 1.22-3.43) were increased, but there was not a favorable neurologic outcome (RR: 1.22, 95% CI: 0.99-1.51).

CONCLUSIONS

In OHCA, standard or high doses of epinephrine should be used because they improved survival to hospital discharge and resulted in a meaningful clinical outcome. There was also a clear advantage of using epinephrine over a placebo or no drugs in the considered outcomes.

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.

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.

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

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

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

OBJECTIVE

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

DATA SOURCES

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

STUDY SELECTION

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

RESULTS

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

CONCLUSIONS

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

Effects of extracorporeal cardiopulmonary resuscitation on neurological and cardiac outcome after ischaemic refractory cardiac arrest

BACKGROUND

Extracorporeal cardiopulmonary resuscitation is increasingly recognised as a rescue therapy for refractory cardiac arrest, nevertheless data are scanty about its effects on neurologic and cardiac outcome. The aim of this study is to compare clinical outcome in patients with cardiac arrest of ischaemic origin (i.e. critical coronary plaque during angiography) and return of spontaneous circulation during conventional cardiopulmonary resuscitation vs refractory cardiac arrest patients needing extracorporeal cardiopulmonary resuscitation. Moreover, we tried to identify predictors of survival after successful cardiopulmonary resuscitation.

METHODS

We enrolled 148 patients with ischaemic cardiac arrest admitted to our hospital from 2011-2015. We compared clinical characteristics, cardiac arrest features, neurological and echocardiographic data obtained after return of spontaneous circulation (within 24 h, 15 days and six months).

RESULTS

Patients in the extracorporeal cardiopulmonary resuscitation group ( n=63, 43%) were younger (59±9 vs 63±8 year-old, p=0.02) with lower incidence of atherosclerosis risk factors than those with conventional cardiopulmonary resuscitation. In the extracorporeal cardiopulmonary resuscitation group, left ventricular ejection fraction was lower than conventional cardiopulmonary resuscitation at early echocardiography (19±16% vs 37±11 p<0.01). Survivors in both groups showed similar left ventricular ejection fraction 15 days and 4-6 months after cardiac arrest (46±8% vs 49±10, 47±11% vs 45±13%, p not significant for both), despite a major extent and duration of cardiac ischaemia in extracorporeal cardiopulmonary resuscitation patients. At multivariate analysis, the total cardiac arrest time was the only independent predictor of survival.

CONCLUSIONS

Extracorporeal cardiopulmonary resuscitation patients are younger and have less comorbidities than conventional cardiopulmonary resuscitation, but they have worse survival and lower early left ventricular ejection fraction. Survivors after extracorporeal cardiopulmonary resuscitation have a neurological outcome and recovery of heart function comparable to subjects with return of spontaneous circulation. Total cardiac arrest time is the only predictor of survival after cardiopulmonary resuscitation in both groups.

The incidence and characteristics of 3-month mortality after intraoperative cardiac arrest in adults

BACKGROUND

There is little information about clinical outcomes after intraoperative cardiac arrest (IOCA). We determined the incidence and characteristics of 3-month mortality after IOCA.

METHODS

The electronic medical records of 238,648 adult surgical patients from January 2005 to December 2014 were reviewed retrospectively. Characteristics of IOCA were documented using the Utstein reporting template.

RESULTS

IOCA occurred in 50 patients (21/100,000 surgeries). Nineteen patients died in the operating room, and further 12 patients died within 3 months post-arrest (total mortality: 62%). Three survivors at 3 months post-arrest had unfavourable neurological outcome. Finally, 34 patients showed unfavourable clinical outcomes at 3 months post-arrest. The incidences of non-cardiac surgery, emergency, pre-operative intubation state, non-shockable initial cardiac rhythm, hypovolaemic shock, pre-operative complications-induced cardiac arrest, non-anaesthetic cause of cardiac arrest, intra- and post-arrest transfusion, and continuous infusion of inotrope or vasopressor in intensive care unit (ICU) were significantly higher in non-survivors at 3 months post-arrest. Total epinephrine dose administrated during arrest was higher, and the duration of cardiac compressions was longer in non-survivors at 3 months post-arrest.

CONCLUSIONS

In this study, the incidence of IOCA was 21/100,000 surgeries and the 3-month mortality rate after IOCA was 62%. Several factors including surgical emergency, non-shockable initial cardiac rhythm, pre-operative complications, surgical complications, long duration of cardiac compressions, high total epinephrine dose, transfusion, and continuous infusion of inotropes or vasopressors in ICU seemed to be risk factors for 3-month mortality after IOCA. These risk factors should be considered in the light of relatively small sample size of this study.

Systematic review of the effectiveness of prehospital critical care following out-of-hospital cardiac arrest

BACKGROUND

Improving survival after out-of-hospital cardiac arrest (OHCA) is a priority for modern emergency medical services (EMS) and prehospital research. Advanced life support (ALS) is now the standard of care in most EMS. In some EMS, prehospital critical care providers are also dispatched to attend OHCA. This systematic review presents the evidence for prehospital critical care for OHCA, when compared to standard ALS care.

METHODS

We searched the following electronic databases: PubMed, EmBASE, CINAHL Plus and AMED (via EBSCO), Cochrane Database of Systematic Reviews, DARE, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, NIHR Health Technology Assessment Database, Google Scholar and ClinicalTrials.gov. Search terms related to cardiac arrest and prehospital critical care. All studies that compared patient-centred outcomes between prehospital critical care and ALS for OHCA were included.

RESULTS

The review identified six full text publications that matched the inclusion criteria, all of which are observational studies. Three studies showed no benefit from prehospital critical care but were underpowered with sample sizes of 1028-1851. The other three publications showed benefit from prehospital critical care delivered by physicians. However, an imbalance of prognostic factors and hospital treatment in these studies systematically favoured the prehospital critical care group.

CONCLUSION

Current evidence to support prehospital critical care for OHCA is limited by the logistic difficulties of undertaking high quality research in this area. Further research needs an appropriate sample size with adjustments for confounding factors in observational research design.

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.

Epinephrine in cardiac arrest: systematic review and meta-analysis

Objective

evaluate the effectiveness of epinephrine used during cardiac arrest and its effect on the survival rates and neurological condition.

Method

systematic review of scientific literature with meta-analysis, using a random effects model. The following databases were used to research clinical trials and observational studies: Medline, Embase and Cochrane, from 2005 to 2015.

Results

when the Return of Spontaneous Circulation (ROSC) with administration of epinephrine was compared with ROSC without administration, increased rates were found with administration (OR 2.02. 95% CI 1.49 to 2.75; I2 = 95%). Meta-analysis showed an increase in survival to discharge or 30 days after administration of epinephrine (OR 1.23; 95% IC 1.05-1.44; I2=83%). Stratification by shockable and non-shockable rhythms showed an increase in survival for non-shockable rhythm (OR 1.52; 95% IC 1.29-1.78; I2=42%). When compared with delayed administration, the administration of epinephrine within 10 minutes showed an increased survival rate (OR 2.03; 95% IC 1.77-2.32; I2=0%).

Conclusion

administration of epinephrine appears to increase the rate of ROSC, but when compared with other therapies, no positive effect was found on survival rates of patients with favorable neurological status.

Chest compression fraction in ambulance while transporting patients with out-of-hospital cardiac arrest to the hospital in rural Taiwan

INTRODUCTION

Maintaining the standard two-handed chest compression is difficult in high-speed ambulances in rural areas.

METHODS

A retrospective, video-based, observational study was conducted from June to September 2013 in Nantou, a rural county of central Taiwan, to evaluate the chest compression fraction in an ambulance carriage during the travel from the scene to the hospital. The chest compression fraction was calculated as the chest compression time period divided by the ambulance travelling time period; the one-handed and two-handed chest compression fractions were also calculated.

RESULTS

During the 4-month study period, a total of 102 videos that were recorded in an ambulance carriage were reviewed, including 97 cases of manual chest compressions. When there was only one emergency medical technician (EMT) in the carriage, the combined chest compression fraction was 50.6±20.7%; when there were two EMTs, the fraction was 58.3±16.0% and the fraction was 58.3±21.0% in a three-EMT scenario (p=0.221). Moreover, in the carriage, EMTs usually performed one-handed chest compressions.

CONCLUSIONS

The chest compression fraction was low for patients with out-of-hospital cardiac arrest in a moving ambulance, irrespective of the number of providers. Reasons for this observation, as well as the effectiveness of the one-handed chest compression require further evaluation.

Pre-hospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug administration In Cardiac arrest (PARAMEDIC-2): Trial protocol

Despite its use since the 1960s, the safety or effectiveness of adrenaline as a treatment for cardiac arrest has never been comprehensively evaluated in a clinical trial. Although most studies have found that adrenaline increases the chance of return of spontaneous circulation for short periods, many studies found harmful effects on the brain and raise concern that adrenaline may reduce overall survival and/or good neurological outcome. The PARAMEDIC-2 trial seeks to determine if adrenaline is safe and effective in out-of-hospital cardiac arrest. This is a pragmatic, individually randomised, double blind, controlled trial with a parallel economic evaluation. Participants will be eligible if they are in cardiac arrest in the out-of-hospital environment and advanced life support is initiated. Exclusions are cardiac arrest as a result of anaphylaxis or life threatening asthma, and patient known or appearing to be under 16 or pregnant. 8000 participants treated by 5 UK ambulance services will be randomised between December 2014 and August 2017 to adrenaline (intervention) or placebo (control) through opening pre-randomised drug packs. Clinical outcomes are survival to 30 days (primary outcome), hospital discharge, 3, 6 and 12 months, health related quality of life, and neurological and cognitive outcomes (secondary outcomes). Trial registration (ISRCTN73485024).

BET 2: Usefulness of epinephrine in out-of-hospital cardiac arrest

A short-cut review was carried out to establish whether prehospital adrenaline affects long-term morbidity or mortality after out-of-hospital cardiac arrest. Fifty-five papers were found using the reported search. Of these, three presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are tabulated. It is concluded that while epinephrine used as an adjunctive treatment during out-of-hospital cardiac arrest (OHCA) may improve return of spontaneous circulation (ROSC) and survival to hospital, it does not improve survival to discharge or neurological outcome.

Early administration of epinephrine (adrenaline) in patients with cardiac arrest with initial shockable rhythm in hospital: propensity score matched analysis

OBJECTIVES

To evaluate whether patients who experience cardiac arrest in hospital receive epinephrine (adrenaline) within the two minutes after the first defibrillation (contrary to American Heart Association guidelines) and to evaluate the association between early administration of epinephrine and outcomes in this population.

DESIGN

Prospective observational cohort study.

SETTING

Analysis of data from the Get With The Guidelines-Resuscitation registry, which includes data from more than 300 hospitals in the United States.

PARTICIPANTS

Adults in hospital who experienced cardiac arrest with an initial shockable rhythm, including patients who had a first defibrillation within two minutes of the cardiac arrest and who remained in a shockable rhythm after defibrillation.

INTERVENTION

Epinephrine given within two minutes after the first defibrillation.

MAIN OUTCOME MEASURES

Survival to hospital discharge. Secondary outcomes included return of spontaneous circulation and survival to hospital discharge with a good functional outcome. A propensity score was calculated for the receipt of epinephrine within two minutes after the first defibrillation, based on multiple characteristics of patients, events, and hospitals. Patients who received epinephrine at either zero, one, or two minutes after the first defibrillation were then matched on the propensity score with patients who were "at risk" of receiving epinephrine within the same minute but who did not receive it.

RESULTS

2978 patients were matched on the propensity score, and the groups were well balanced. 1510 (51%) patients received epinephrine within two minutes after the first defibrillation, which is contrary to current American Heart Association guidelines. Epinephrine given within the first two minutes after the first defibrillation was associated with decreased odds of survival in the propensity score matched analysis (odds ratio 0.70, 95% confidence interval 0.59 to 0.82; P<0.001). Early epinephrine administration was also associated with a decreased odds of return of spontaneous circulation (0.71, 0.60 to 0.83; P<0.001) and good functional outcome (0.69, 0.58 to 0.83; P<0.001).

CONCLUSION

Half of patients with a persistent shockable rhythm received epinephrine within two minutes after the first defibrillation, contrary to current American Heart Association guidelines. The receipt of epinephrine within two minutes after the first defibrillation was associated with decreased odds of survival to hospital discharge as well as decreased odds of return of spontaneous circulation and survival to hospital discharge with a good functional outcome.

[Which drugs are useful during resuscitation? Which are not?]

INTRODUCTION

Cardiopulmonary resuscitation represents a therapeutic challenge. Evidence-based guidelines, which were updated in 2015, give detailed advice on how to treat the patient.

METHODS

Basic life support consists of cardiopulmonary resuscitation (30 chest compressions interrupted briefly to provide to 2 ventilations) and, if ventricular tachyarrhythmia is present, urgent cardiac defibrillation. Administration of drugs is one of the aspects of advanced life support. Vasopressors (adrenaline, vasopressin) aim to optimize coronary and cerebral perfusion. Antiarrhythmic drugs (amiodarone or lidocaine, when amiodarone is not available) are given during cardiac arrest to treat specific cardiac arrhythmias, mainly ventricular fibrillation and ventricular tachycardia.

CONCLUSION

However, even in current guidelines, there is growing ambivalence towards drug treatment in the setting of cardiopulmonary resuscitation. This is mainly due to a paucity of robust clinical data. Most of the studies that have addressed the efficacy and safety of drugs during resuscitation are observational studies; however, a few small randomized controlled studies also exist. Recently, two large randomized controlled studies addressing the efficacy and safety of adrenaline versus placebo and amiodarone or lidocaine versus placebo have started. Both are currently recruiting patients. The hope is that the results of these studies will help to better define the role of drugs administered during cardiopulmonary resuscitation.

Myocardial Dysfunction and Shock after Cardiac Arrest

Postarrest myocardial dysfunction includes the development of low cardiac output or ventricular systolic or diastolic dysfunction after cardiac arrest. Impaired left ventricular systolic function is reported in nearly two-thirds of patients resuscitated after cardiac arrest. Hypotension and shock requiring vasopressor support are similarly common after cardiac arrest. Whereas shock requiring vasopressor support is consistently associated with an adverse outcome after cardiac arrest, the association between myocardial dysfunction and outcomes is less clear. Myocardial dysfunction and shock after cardiac arrest develop as the result of preexisting cardiac pathology with multiple superimposed insults from resuscitation. The pathophysiology involves cardiovascular ischemia/reperfusion injury and cardiovascular toxicity from excessive levels of inflammatory cytokine activation and catecholamines, among other contributing factors. Similar mechanisms occur in myocardial dysfunction after cardiopulmonary bypass, in sepsis, and in stress-induced cardiomyopathy. Hemodynamic stabilization after resuscitation from cardiac arrest involves restoration of preload, vasopressors to support arterial pressure, and inotropic support if needed to reverse the effects of myocardial dysfunction and improve systemic perfusion. Further research is needed to define the role of postarrest myocardial dysfunction on cardiac arrest outcomes and identify therapeutic strategies.

Therapeutic hypothermia after nonshockable cardiac arrest: the HYPERION multicenter, randomized, controlled, assessor-blinded, superiority trial

BACKGROUND

Meta-analyses of nonrandomized studies have provided conflicting data on therapeutic hypothermia, or targeted temperature management (TTM), at 33°C in patients successfully resuscitated after nonshockable cardiac arrest. Nevertheless, the latest recommendations issued by the International Liaison Committee on Resuscitation and by the European Resuscitation Council recommend therapeutic hypothermia. New data are available on the adverse effects of therapeutic hypothermia, notably infectious complications. The risk/benefit ratio of therapeutic hypothermia after nonshockable cardiac arrest is unclear.

METHODS

HYPERION is a multicenter (22 French ICUs) trial with blinded outcome assessment in which 584 patients with successfully resuscitated nonshockable cardiac arrest are allocated at random to either TTM between 32.5 and 33.5°C (therapeutic hypothermia) or TTM between 36.5 and 37.5°C (therapeutic normothermia) for 24 hours. Both groups are managed with therapeutic normothermia for the next 24 hours. TTM is achieved using locally available equipment. The primary outcome is day-90 neurological status assessed by the Cerebral Performance Categories (CPC) Scale with dichotomization of the results (1 + 2 versus 3 + 4 + 5). The primary outcome is assessed by a blinded psychologist during a semi-structured telephone interview of the patient or next of kin. Secondary outcomes are day-90 mortality, hospital mortality, severe adverse events, infections, and neurocognitive performance. The planned sample size of 584 patients will enable us to detect a 9% absolute difference in day-90 neurological status with 80% power, assuming a 14% event rate in the control group and a two-sided Type 1 error rate of 4.9%. Two interim analyses will be performed, after inclusion of 200 and 400 patients, respectively.

DISCUSSION

The HYPERION trial is a multicenter, randomized, controlled, assessor-blinded, superiority trial that may provide an answer to an issue of everyday relevance, namely, whether TTM is beneficial in comatose patients resuscitated after nonshockable cardiac arrest. Furthermore, it will provide new data on the tolerance and adverse events (especially infectious complications) of TTM at 32.5-33.5°C.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01994772 .