Lower Body Perfusion Combined With Mild Hypothermia in Aortic Arch Surgery: A Randomized Comparison With Moderate Hypothermia

Background: Lower antegrade body perfusion (LABP) can shorten the duration of hypothermic circulatory arrest. However, the efficacy of LABP combined with mild hypothermic circulatory arrest (MiHCA) remains unclear. This randomized controlled trial investigated whether applying LABP during total arch replacement (TAR) improves clinical outcomes compared to moderate hypothermic circulatory arrest (MoHCA). Methods: Adult patients undergoing first-time TAR were randomly assigned to the MiHCA group (n = 147, MiHCA + LABP) or the MoHCA group (n = 147). Primary outcomes included the incidence of temporary neurological dysfunction (TND), permanent neurological deficit (PND), acute kidney injury (AKI), and serum alanine aminotransferase (ALT) levels. Results: The baseline characteristics were comparable between the groups. No significant differences were observed in the incidence of TND or PND. However, the MiHCA group had a significantly shorter circulatory arrest time (5 vs. 16 minutes; p < 0.001), lower incidence of AKI (29.9% vs. 41.5%; p = 0.039), and lower ALT levels at 24 hours postoperatively (39.3 vs. 48.0 U/L; p = 0.012). Conclusion: MiHCA combined with LABP appears to be a safe and feasible strategy in total arch replacement for acute type A aortic dissection. The addition of LABP significantly reduces the time of circulatory arrest, which may contribute to lower rates of AKI and improved hepatic function postoperatively. Clinical Trial Registration: ChiCTR2000033852, https://www.chictr.org.cn/hvshowproject.html?id=38552&v=1.1.