Authors: Zafar T, Hamid M
Cureus 18(7): e112347. doi:10.7759/cureus.112347
Background
Unintended perioperative hypothermia is a frequent side effect of general anesthesia and is related to early postoperative symptoms such as shivering and postoperative nausea and vomiting (PONV). Forced air warming (FAW), as performed with the Bair Hugger system, is commonly used during long procedures for the maintenance of normothermia. However, its effectiveness in reducing these postoperative symptoms in patients undergoing laparoscopic surgery remains uncertain.
Methods
This single-blind randomized controlled trial was conducted at Aga Khan University Hospital, Karachi, between January 1, 2023, and April 10, 2024. Ninety-eight American Society of Anesthesiologists (ASA) I and II patients between the ages of 18 and 65 undergoing laparoscopic surgery were included. These patients were randomized by opaque-envelope allocation technique to the FAW group and the control group (non-FAW). Core temperature was monitored with a nasopharyngeal temperature probe at 30-min intervals. Outcome variables like shivering (BSAS) and PONV scores were recorded at 30 min and 6 h post-extubation in the post-anesthesia care unit (PACU).
Results
Intraoperative use of FAW significantly reduces the incidence of shivering in the first 30 minutes (p=0.004) and, later, when compared with the control group. PONV incidence did not differ at 30 min (p=0.232) and at 6 h (p=0.673).
Conclusions
Forced air warmers help in maintaining intraoperative temperatures and significantly reduce the incidence of postoperative shivering in laparoscopic surgeries, but have no significant effect on nausea and vomiting.