Abstract Background Continuous renal replacement therapy (CRRT) represents a critical complication following extensive aortic arch repair for type A aortic dissection (TAAD), significantly influencing patients’ early and long-term outcomes. Hypothermic circulatory arrest, a fundamental technique in aortic arch surgery, has been independently identified as a risk factor for postoperative renal injury, which consequently increases the likelihood of CRRT requirement. Purpose This study aims to evaluate the impact of different temperature strategies during HCA on postoperative CRRT requirements, potentially providing clinically significant insights for surgical management and patient outcomes in extensive aortic arch repair. Methods A total of 1283 patients with TAAD who underwent total arch replacement with frozen elephant trunk procedure in our center were retrospectively enrolled between 2010.01 and 2018.12, and were divided into 2 groups: with postoperative CRRT (N = 123) and without postoperative CRRT (N = 1160). Patients with preoperative dialysis were excluded. The core temperature was categorized into deep hypothermia (≤20°C), low-moderate hypothermia (20.1-24°C), high-moderate hypothermia (24.1-28°C), and mild hypothermia (28°C), according to 2024 EACTS/STS guidelines. Results Patients in the CRRT group exhibited significantly higher early mortality compared to the non-CRRT group (38.2% vs. 3.7%, P0.001). During a median follow-up of 6.02 years, long-term survival was significantly lower in the CRRT group (Log-rank: P0.001), though post-operative quality of life remained comparable between groups (Fine-Gray: P=0.905). Notably, among the survivors in the CRRT group, the majority (81.0%, 51/63) recovered renal function without requiring further dialysis. Long-term survival of CRRT patients showed no significant differences across different core temperature groups (Log-rank: P=0.323). Multivariate logistic regression revealed a significant interaction between core temperature and cardiopulmonary bypass (CPB) time. By incorporating the interaction term into the final regression model, higher temperature groups demonstrated protective effects compared to deep hypothermia (P for trend = 0.001). However, the predicted probability curves revealed that the protective effect of higher core temperatures gradually diminished with prolonged CPB time, and for CPB durations exceeding 250 minutes, higher temperature groups potentially became risk factors, while deep hypothermia showed more stable outcomes across different CPB durations. Conclusions Generally, higher core temperatures are more suitable during total arch replacement with frozen elephant trunk procedure. However, for complex surgeries with prolonged CPB time, caution is warranted regarding potential renal injury associated with increased core temperatures. These findings offer critical references for surgical decision-making and future clinical research in extensive aortic arch repair.Figure 1 Figure 2
Zhou et al. (Sat,) studied this question.