Background: The relationship between perioperative temperatures and postoperative pain is unknown. The present study investigated the relationship of intraoperative hypothermia and perioperative opioid requirements after immediate implant-based breast reconstruction.
Methods: A retrospective chart review was conducted on patients undergoing immediate implant-based breast reconstruction from 2019-2023. Patients were classified into the hypothermic group (majority of procedure < 36.0 °C) or normothermic group (majority of procedure ? 36.0 °C). Cumulative inpatient opioid requirements (morphine milli-equivalents [MMEs]) and frequency of patients requiring “high-dose opioids” (? 100 MMEs) were collected and compared between groups.
Results: In total, 536 patients (833 breasts) were included, of which 135 (25.1%) were hypothermic. The hypothermic group had lower mean intraoperative (88.4 vs 99.1 MMEs, P = 0.007) and postoperative (44.2 vs 56.8 MMEs, P = 0.006) than the normothermic group. Mean (B = 14.6, P = 0.004) and nadir (B = 10.4, P = 0.038) intraoperative temperatures directly predicted higher opioid requirements while higher percentages of the procedure time spent under 36 °C (B = -27.6, P = 0.004) predicted lower opioid requirements. The hypothermic group was associated with 67% decreased odds of requiring high-dose opioids when adjusting for differences in age and procedure time (P < 0.001). There were no differences in BMI, nerve blocks, or implant plane between groups.
Conclusion: Hypothermia is associated with decreased perioperative opioid requirements. Excessive warming maneuvers may increase a patient’s risk of requesting high-dose opioids postoperatively.