Regional Cerebral Oxygen Saturation to Predict Favorable Outcome in Extracorporeal Cardiopulmonary Resuscitation: A Systematic Review and Meta-Analysis

Objective: This systematic review and meta-analysis aimed to investigate the role of regional cerebral oxygen saturation (rSO2) in predicting survival and neurologic outcomes after extracorporeal cardiopulmonary resuscitation (ECPR). Design: The study authors performed a systematic review and meta-analysis of all available literature. Setting: The authors searched relevant databases (Pubmed, Medline, Embase) for studies measuring precannulation rSO2 in patients undergoing ECPR and reporting mortality and/or neurologic outcomes. Participants: The authors included both in-hospital and out-of-hospital cardiac arrest patients receiving ECPR. They identified 3 observational studies, including 245 adult patients. Interventions: The authors compared patients with a low precannulation rSO2 (≤15% or 16%) versus patients with a high (>15% or 16%) precannulation rSO2. In addition, the authors carried out subgroup analyses on out-of-hospital cardiac arrest (OHCA) patients. Measurements and Main Results: A high precannulation rSO2 was associated with an overall reduced risk of mortality in ECPR recipients (98 out of 151 patients [64.9%] in the high rSO2 group, v 87 out of 94 patients [92.5%] in the low rSO2 group, risk differences [RD] -0.30; 95% CI -0.47 to -0.14), and in OHCA (78 out of 121 patients [64.5%] v 82 out of 89 patients [92.1%], RD 0.30; 95% CI -0.48 to -0.12). A high precannulation rSO2 also was associated with a significantly better neurologic outcome in the overall population (42 out of 151 patients [27.8%] v 2 out of 94 patients [2.12%], RD 0.22; 95% CI 0.13-0.31), and in OHCA patients (33 out of 121 patients [27.3%] v 2 out of 89 patients [2.25%] RD 0.21; 95% CI 0.11-0.30). Conclusions: A low rSO2 before starting ECPR could be a predictor of mortality and survival with poor neurologic outcomes.