Liang Cao L, Xiaoxiao Guo, Yuan Jia, et al. - Via performing a systematic review and meta‐analysis, researchers sought to directly compare the postoperative renal function of moderate hypothermic circulatory arrest (MHCA) vs deep hypothermic circulatory arrest (DHCA) in aortic arch surgery. They searched PubMed, Embase, and the Cochrane Library, identifying a total of 14 observational studies with 4,142 patients for inclusion. Outcomes revealed reduced incidence of renal failure and necessity for renal replacement in correlation with MHCA vs DHCA. Subgroup analysis indicated significantly lower incidence of renal failure in MHCA group than that in DHCA group when the hypothermic circulatory arrest time was < 30 minutes, whereas there was an insignificant difference between 2 groups when hypothermic circulatory arrest time was > 30 minutes.