title: A meta-analysis of the success rates of heartbeat restoration within the platinum 10 min among outpatients suffering from sudden cardiac arrest in China.
abstract: BACKGROUND
  The optimal time to save a person who has had a sudden cardiac arrest is within the first few minutes of the incident. Early compression and early defibrillation should be performed at this time. Timeliness is the key to successful CPR; as such, Prof. He proposed the "platinum 10 min" system to study early CPR issues. This paper systematically evaluates the success rates of heartbeat restoration within the "platinum 10 min" among patients suffering from sudden cardiac arrest.
  
  
  METHODS
  The clinical data of outpatients suffering from a cardiac arrest were retrieved from the China Knowledge Network (January 1975-January 2015), the Chongqing VIP database (January 1989-January 2015), and the Wanfang database (January 1990-January 2015). The success of the cardiopulmonary resuscitation (CPR) performed at different times after the patients had cardiac arrests was analyzed. Two researchers screened the literature and extracted the data independently. A meta-analysis was conducted using Stata12.0. A total of 57 papers met the inclusion criteria, including 29,269 patients. Of these patients, 1776 had their heartbeats successfully restored. The results showed high heterogeneity (X (2)  = 3428.85, P < 0.01, I(2) = 98.4 %). The meta-analysis was conducted using a random-effects model. The combined effect size was 0.171 (0.144-0.199).
  
  
  RESULTS
  (1) The success rate of heartbeat restoration did not differ among the four emergency treatment methods that patients received: the methods described in the 2000 Guidelines for CPR and Emergency Cardiovascular Care, that described in the 2005 version, 2010 version, and another CPR method. (2) The patients were divided into five groups based on the time when CPR was performed: the ≤1 min group, the 1- ≤ 5 min group, the 5- ≤ 10 min group, the 10- ≤ 15 min group and the >15 min group. The CPR success rates of these five groups were 0.247 (0.15-0.344), 0.353 (0.250-0.456), 0.136 (0.109-0.163), 0.058 (0.041-0.075), and 0.011 (0.004-0.019), respectively. The CPR success rates did not differ between the patients in the ≤1 min group and the 1- ≤ 5 min group. This success rate was higher for the patients in the 1- ≤ 5 min group than those in the 10- ≤ 15 min group, those in the 10- ≤ 15 min group, and those in the >15 min group. The CPR success rate was higher for the patients in the 5-10 min group than those in the 10- ≤ 15 min group and those in the >15 min group.
  
  
  CONCLUSIONS
  The CPR success rate was higher for the patients in the 10- ≤ 15 min group than those in the >15 min group. In addition, the patients were divided into two groups based on whether CPR was performed within the first 10 min after the cardiac arrest occurred: the ≤10 min group and the >10 min group. The CPR success rate was higher for the patients in the ≤10 min group (0.189 [0.161-0.218]) than those in the >10 min group (0.044 [0.032-0.056]). (3) Differences were not found between the CPR success rates among the patients in the telephone guidance group (0.167 [0.016-0.351]) and those in the ≤1 min, 1- ≤ 5 min, 5- ≤ 10 min, 10- ≤ 15 min, and >15 min groups. (4) The CPR success rates did not differ among in the patients in the witness + public group (0.329 [0.221-0.436]), those in the ≤1 min group, and those in the 1- ≤ 5 min group. However, this success rate was higher in the patients in the witness + public group than those in the 5- ≤ 10 min, 10- ≤ 15 min, and >15 min groups.
  
  
  CONCLUSIONS
  The success rate of heartbeat restoration did not differ among patients receiving CPR based on different guidelines. The success rate of CPR lies in its timeliness. The participation of the general population is the cornerstone of improving CPR. Providing complete emergency treatment equipment and perfecting comprehensive measures can improve the success rate of CPR among patients within the platinum 10 min. CPR research in China must be improved.
authors.affiliation: School of Graduate, Liaoning Medical College, Jinzhou, Liaoning 121001 China.
authors.forename: Xiang-Min
authors.initials: XM
authors.lastname: Gu
authors.affiliation: School of Graduate, Liaoning Medical College, Jinzhou, Liaoning 121001 China.
authors.forename: Zhi-Hui
authors.initials: ZH
authors.lastname: Li
authors.affiliation: Department of ICU, First Affiliated Hospital, General Hospital of PLA, Beijing, 100036 China.
authors.forename: Zhong-Jie
authors.initials: ZJ
authors.lastname: He
authors.affiliation: Department of ICU, First Affiliated Hospital, General Hospital of PLA, Beijing, 100036 China.
authors.forename: Zhe-Wei
authors.initials: ZW
authors.lastname: Zhao
authors.affiliation: Department of ICU, First Affiliated Hospital, General Hospital of PLA, Beijing, 100036 China.
authors.forename: Shuang-Qing
authors.initials: SQ
authors.lastname: Liu
keywords: Cardiac arrest; Cardiopulmonary resuscitation; First aid; Meta-analysis; Platinum 10 minutes; Time-efficiency