A Meta-analysis Of The Efficacy And Safety Of Epinephrine In Resuscitation Of Out Of Hospital Cardiac Arrest Patients

Objective:In recent years,the application of epinephrine in cardiopulmonary resuscitation has been controversial.In this paper,the efficacy and safety of epinephrine in resuscitation of out of hospital cardiac arrest(OHCA)patients were evaluated by meta-analysis.Methods:Searched all randomized controlled studies and cohort studies on the evaluation of resuscitation effects in OHCA patients with or without epinephrine which published on Cochrane Library,Pubmed,Embase from inception until 2019-09-30.Inclusion criteria:(1)Patients:OHCA patients(age≥18 years old);(2)Intervention:evaluated the resuscitation effects in OHCA patients with or without epinephrine;(3)Outcomes:the primary outcome indicator:survival to hospital discharge;the secondary outcome Indicators:the return of spontaneous circulation(ROSC),survival to hospital admission and favorable neurologic outcome on discharge.At least one of the above outcome indicators must be contained in every included study;(4)Study types:randomized controlled trial and cohort studies.Exclusion criteria:(1)The subjects of the study were in-hospital cardiac arrest patients,children,animals;(2)Only epinephrine was studied,no control group was set up for comparison;(3)The original data did not include the outcome indicators involved in this study;(4)The study type did not conform to the randomized controlled trial or cohort study;(5)Only the title and abstract were obtained,the original text and enough original data could not be acquired;(6)For multiple published documents,selected the most comprehensive one to avoid repeated references.After information collection and quality evaluation of the included literature,meta-analysis was conducted with RevMan5.3 software.Result:In this meta-analysis,22 studies(5 randomized controlled studies and 17 cohort studies)with a total of 678,135 OHCA patients were included.And there were 60,683cases in the adrenaline group and 617,452 cases in the non-adrenaline group.The results showed that although epinephrine(experimental group)increased ROSC rate in OHCA patients compared with the control group[relative risk(RR)1.66;95%confidence interval(CI)1.15-2.40;P=0.007,I~2=100%],it worsened neurologic outcome(RR 0.68;95%CI 0.50-0.92;P=0.01,I~2=93%);There was no significant difference in survival to admission and survival to discharge(survival to admission:RR 1.29;95%CI 0.93-1.79;P=0.12,I~2=97%;survival to discharge:RR 1.01;95%CI 0.80-1.28;P=0.90,I~2=95%).Subgroup analysis was conducted according to different initial rhythm.The results showed that the rate of survival to discharge in OHCA patients whose initial rhythm was PEA/asystole was higher in the experimental group than in the control group(survival to discharge:RR 1.52;95%CI 1.23-1.89;P=0.0002 I~2=61%);But the other three outcomes had no significant difference(ROSC;RR 2.16;95%CI 0.81-5.78;P=0.12,I~2=100%;survival to admission:RR 1.37;95%CI 0.87-2.14;P=0.18,I~2=95%;favorable neurologic outcome:RR 0.99;95%CI 0.67-1.45;P=0.95,I~2=53%);For OHCA patients with an initial rhythm of VF/VT,the rate of favorable neurologic outcome in the experimental group was lower than that in the control group(RR 0.53;95%CI 0.31-0.91;P=0.02,I~2=93%),But the other three outcomes had no significant difference(ROSC:RR 1.13;95%CI 0.79-1.61;P=0.51,I~2=94%;survival to admission:RR 1.00;95%CI0.82-1.21;P=0.97,I~2=69%;survival to discharge:RR 0.74;95%CI 0.51-1.08;P=0.12,I~2=94%).Conclusion:The use of epinephrine increases ROSC rates in OHCA patients,but it worsens neurologic outcome.When the initial rhythm is PEA/asystole,the use of epinephrine is associated with increased survival to discharge.When the initial rhythm is VF/VT,the use of epinephrine may adversely affect the recovery of the patient’s nerve function.