Postoperative hypothermia after total aortic arch replacement in acute type A aortic dissection-multivariate analysis and risk identification for postoperative hypothermia occurrence.

Background: Postoperative hypothermia (PH) is a common physiological abnormality associated with increased morbidity and mortality after non-cardiac surgery. The incidence, risk factors of PH and its impact on early outcomes after total aortic arch replacement are not clear.

Methods: We conducted a retrospective cohort study in patients with acute type A aortic dissection who underwent total arch replacement from January 2013 to December 2016 at our institution. Basic variables, procedural and postoperative early outcomes were collected. Univariate and multivariate statistical analysis were performed for statistical interpretation. The early outcomes were compared between patients with or without PH.

Results: A total of 300 patients (age 53.8±11.5 years, female 63, 21.0%) with acute type A aortic dissection underwent total arch replacement. Forty-four patients (14.7%) developed PH. The independent risk factors of PH are age and the intraoperative lowest bladder temperature. There is no significant difference in major postoperative morbidity and mortality between patients with or without PH.

Conclusions: The incidence of PH after total arch replacement in acute type A aortic dissection is relatively low. The independent risk factors of PH in this population include age and the intraoperative lowest bladder temperature. With comprehensive rewarming strategy upon arrival at the ICU, the PH is easy to be corrected, and the adverse effect of transient PH on early outcomes after arch surgery is minimal.