[Effects of extracorporeal cardiopulmonary resuscitation for adult patients with out-of-hospital cardiac arrest on survival rate and neurological outcome: a Meta-analysis].

Objective: To compare the influences of extracorporeal cardiopulmonary resuscitation (ECPR) and conventional or mechanical cardiopulmonary resuscitation (CCPR/MCPR) on survival rate and neurological outcome for adult patients with out-of-hospital cardiac arrest (OHCA), and to assess the effect of ECPR.

Methods: Databases such as Medline, Embase, ScienceDirect, HighWire, Cochrane Library, Wanfang Database and China National Knowledge Infrastructure (CNKI) were searched from January 2000 to October 2018 to retrieve clinical trials on comparison of the effect of ECPR and CCPR/MCPR on survival rate and neurological outcome of adult patients with OHCA. Thereafter, the studies retrieved were based on predefined inclusion and exclusion criteria. Data were extracted and the quality of the included studies was evaluated by two researchers. A meta-analysis was performed by using RevMan 5.3 software. Sensitivity analysis was used to evaluate the stability of the results, and funnel plot was used to evaluate publication bias.

Results: A total of 12 studies and 2 519 patients were enrolled, including 615 patients receiving ECPR and 1 904 patients receiving CCPR/MCPR. Meta-analysis showed that compared with CCPR/MCPR, ECPR could not improve the short-term (at hospital discharge or within 1 month) survival rate in patients with OHCA [odds ratio (OR) = 2.26, 95% confidence interval (95%CI) = 0.95-5.41, P = 0.07], but could increase long-term (at more than 3 months) survival rate (OR = 3.56, 95%CI = 1.65-7.71, P = 0.001), rate of good neurological outcome at hospital discharge [Glasgow-Pittsburgh cerebral performance categories (CPC) 1-2 was defined as good neurological function; OR = 3.39, 95%CI = 1.73-6.62, P = 0.000 4], and rate of good long-term neurological outcome (OR = 3.45, 95%CI = 2.24-5.32, P < 0.000 01). Sensitivity analysis showed that the overall results did not change significantly, whether using fixed-effect model and random-effect model to analyze the differences of each effect index, or excluding one study with fewer than 50 subjects for data analysis, indicating that the results were more stable. The funnel plot suggested that there was no publication bias in the studies. But due to the small number of studies, the publication bias could not be excluded.

Conclusions: ECPR could not improve the short-term survival rate at hospital discharge or within 1 month in patients with OHCA, but could increase long-term survival rate at more than 3 months, good neurological outcome at hospital discharge and long-term neurological outcome.