The effects of prolonged intraoperative hypothermia on patient outcomes in immediate implant-based breast reconstruction.

BACKGROUND: The importance of thermoregulation in surgical procedures has become a recent focus for anesthesiologists and surgeons to improve patient outcomes. In breast surgery, maintenance of normothermia has been shown to reduce surgical-site infections. However, there is a paucity of information evaluating the relationship between intraoperative core body temperatures and reconstructive surgical outcomes. METHODS: A retrospective review of patients who underwent immediate breast reconstruction following mastectomy from 2015 to 2020 was performed. Patients were classified into a majority normothermic (NT) group if patients spent greater than half of the operative time ≥36 °C or a majority hypothermic (HT) group if patients spent greater than or equal to half of the operative time <36 °C. Patient demographics, comorbidities, surgical techniques, and postoperative complications were recorded. Complications were classified according to the Clavien-Dindo Classification. Univariate and multivariate statistics were used to assess significant relationships. RESULTS: A total of 329 patients met inclusion criteria, of which 174 were in the NT group and 155 were in the HT group, yielding 302 and 264 total breasts, respectively. There was no significant difference in rates of infection (p = 1.0), seroma (p = 0.27), hematoma (p = 0.61), or wound dehiscence (p = 1.0). However, patients in the HT group had significantly more overall ischemic complications (p = 0.009) and, specifically, grade IIIb ischemic complications (p = 0.04). After controlling for tobacco use, body mass index, mastectomy pattern, radiation, operating surgeon, and mastectomy weight, multivariate analysis showed increased ischemic complications in the HT group (p = 0.04). CONCLUSION: Prolonged intraoperative hypothermia can increase the risk for the development of ischemic wounds such as tissue necrosis or eschar formation that require operative intervention. This presents reconstructive complications that increase both patient and health system burdens that could be addressed through the maintenance of normothermia. Further studies using real-time flap temperature would provide more accurate insight into the relationship between temperature and implant-based breast reconstruction.