Epidemiology,prognostic Factors And Gender Differences Of Out-of-hospital Cardiac Arrest In Zhengzhou City

Background and ObjectiveCardiac arrest(CA)seriously threatens our life.Some studies showed that the treatment of out-of-hospital cardiac arrest(OHCA)in China was far from that of developed countries.Although many studies showed that there were many factors influencing the return of spontaneous circulation(ROSC)of OHCA patients,their results were controversial.Some studies showed that there were gender differences in characteristics and survival of patients with OHCA,and they speculated that estrogen might play an important role.However,there was still a lack of studies about gender differences in China.Therefore,our study aimed to explore the epidemiology,prognostic factors,and gender differences of OHCA by analyzing the data of adult with OHCA in Zhengzhou.MethodsThis is a retrospective study.We collected data of adult with OHCA registered in Zhengzhou Emergency Medical Rescue Center between July 2016 and June 2019,including gender,age,etiology(cardiac or non-cardiac),bystander cardiopulmonary resuscitation(CPR)(yes or not),emergency medical service(EMS)response time,initial rhythm(shockable rhythm or others),defibrillation(yes or not),airway(endotracheal intubation or others),epinephrine(yes or not),ROSC(yes or not).General statistical description,Mann-Whitney U test,χ2 test and Logistic regression were used.ResultsA total of 3429 adult with OHCA were included.Epidemiology of OHCA in Zhengzhou:Males were more than females(72.8%vs 27.2%).The median age was 64 years,and the interquartile interval(IQR)was 52-77 years.Cardiac etiology was the main cause of OHCA(64.2%).The median EMS response time was 8 minutes,with IQR 6-11 minutes.Patients were 5.3%with bystander CPR,2.9%with an initial shockable rhythm,11.6%with defibrillation,27.6%with endotracheal intubation,and 99.1%with epinephrine.The ROSC was extremely low(1.3%).Prognostic factors of ROSC:Univariate analysis showed that there were statistical differences of ROSC in age(ROSC group with median 53 years,IQR 46-73 years vs.Non-ROSC group with median 64 years,IQR 52-77 years,P=0.008),bystander CPR(yes 3.9 vs.not 1.2%,P=0.008),initial rhythm(shockable rhythm 7.1%vs.others 1.1%,P--0.000),defibrillation(yes 2.5%vs.not 1.2%,P=0.025),airway(endotracheal intubation 2.3%vs.others 0.9%,P=0.001).Logistic regression analysis showed that older age was a risk factor for ROSC,and bystander CPR,shockable rhythm and endotracheal intubation were protective factors.Gender differences:Compared with men,women were less(27%vs.73%),older(median 74 years with IQR 61-82 years vs.median 62 years with IQR 50-74 years,P=0.000),and less likely to have shockable rhythm(1.7%vs.3.3%,P=0.013),defibrillation(8.9%vs.12.6%,P=0.003).After adjusted with age,bystander CPR,initial rhythm,and airway,there was no gender difference in ROSC(OR=1.472,95%CI 0.751-2.882).There was also no gender difference of ROSC in premenopausal(18-50 years,OR=1.994,95%CI 0.597-6.662),and postmenopausal(>50 years,OR=1.196,95%CI 0.529-2.704)subgroup.ConclusionEpidemiology of OHCA in Zhengzhou:Men were more than women.The age of patients was young.Cardiac etiology was the main cause of OHCA.Compared with developed countries or regions,the proportion of bystander CPR,shockable rhythm,defibrillation,and ROSC were lower,emergency response times were similar,and the use of epinephrine was more.Prognostic factors of ROSC:Older age was a risk factor for ROSC,and bystander CPR,shockable rhythm,and endotracheal intubation were protective factors.Gender differences:Compared with men,women were older,less likely to have shockable rhythm,and defibrillation.Although women had worse characteristics than men,there was no gender difference in ROSC.There was also no gender difference of ROSC in premenopausal and postmenopausal subgroup.