Efficiency and Safety of Temperatures Management in Aortic Arch Surgery: A System Review and Meta-Analysis

Objective. The study evaluates the safety and efficacy of hypothermic cardiac arrest (HCA) at various temperatures in aortic arch surgeries. Methods. We conducted a literature search in PubMed, Google Scholar, and Embase databases. For single proportion assessments, we employed fixed-effect and random-effect models in the general linear mixture model and the inverse variance model for other computations. We analyzed factors such as age, sex, operation time, and postoperative complications, with subgroup and metaregression analyses. We used funnel plots to depict potential publication bias. Results. Our research incorporated 43 papers with 34,797 cases. HCA temperatures were divided into five groups (A: 30–32°C, B: 28–30°C, C: 26–28°C, D: 24–26°C, and E: <24°C). There is no statistically significant difference in myocardial ischemia time ( $P$  = 0.90) and isolated cerebral perfusion (ICP) time ( $P$  = 0.95). Groups A and C have the best performance in avoiding postoperative complications including transient nerve injury (TNI), permanent nerve injury (PNI), renal failure (RF), and mortality occurrence rate. Group A has the lowest occurrence rate in PNI (3%) and mortality (3%). Group C has the lowest RF incidence (5%). Conclusion. Maintaining temperatures of 30–32°C in en bloc anastomosis or 26–28°C during arch replacement with separate grafts can significantly reduce complications including PNI, RF, and in-hospital mortality.