Hybrid operating rooms and the risk of postoperative hypothermia in pregnant women with placenta previa: A retrospective cohort study

by Sou Hyun Lee, You Hyun Lee

Births at advanced maternal ages (≥ 35 years) are increasing. This has been associated with a higher incidence of placenta previa, which increases bleeding risk. Hybrid operating rooms, designed to accommodate interventions and cesarean sections, are becoming more prominent because of their dual capabilities and benefits. However, they have been associated with increased postoperative hypothermia in pediatric settings; moreover, this has not been studied in pregnant women with placenta previa.

This retrospective cohort study included pregnant women diagnosed with placenta previa who underwent elective cesarean section under general anesthesia between May 2019 and 2023. The patients were categorized according to the operating room type. The primary outcome was to determine whether the hybrid operating room is a risk factor for immediate postoperative hypothermia, defined as a tympanic membrane temperature below 36.0°C. The secondary outcomes were the effects of immediate postoperative hypothermia on the durations of postanesthetic care unit and postoperative hospital stays and incidence of complications.

Immediate postoperative hypothermia (tympanic membrane temperature < 36.0°C) was more prevalent in the hybrid than in the standard operating room group (20% vs. 36.6%, p = 0.033), with a relative risk of 2.86 (95% confidence interval 1.24–6.64, p < 0.001). Patients undergoing surgery in the hybrid operating room who experienced immediate postoperative hypothermia stayed longer in the postanesthetic care unit (26 min vs. 40 min, p < 0.001) and in the hospital after surgery (4 days; range 3–5 vs. 4 days; range 4–11, p = 0.021). However, the complication rates of both groups were not significantly different (11.3% vs 7.3%, p = 0.743).

Hybrid operating rooms may increase the risk of postoperative hypothermia. Postoperative hypothermia is associated with prolonged postanesthetic care unit and hospital stays. Preventing hypothermia in patients in hybrid operating rooms is of utmost importance.