A custom-made forced-air warming mattress for heat loss prevention during vascular surgery: Clinical evaluation

Abstract

Perioperative hypothermia causes numerous complications. Severe heat loss from vascular surgery results from the large exposure area and long duration. Objective: To invent a custom-made forced-air warming mattress (FWM) with three appendages covering both arms and to compare its efficacy with the circulating-water mattress (CWM) in prevention of heat loss during vascular surgery. Methods: Forty-four patients age 31-88 years, ASA (American Society of Anesthesiologists) physical status I-III were randomly allocated into two groups using CWM (n = 22) and FWM (n = 22). Demographic data, surgical and anesthetic characteristics, fluid intake/output, and vital signs were recorded. Outcome variables included esophageal, ambient, arm, chest and thigh temperature were recorded at 30-min intervals. Pressure-heat burns at back and buttock were recorded and followed for 3 days. Surgeons' satisfaction with both mattresses was also recorded. Results: There were no differences in patients' surgical and anesthetic characteristics between the two groups. Esophageal, ambient, chest, and left thigh temperatures recorded from 30 to 180 minutes were not different between the groups. CWM group had lower arm temperatures but higher right thigh temperatures than FWM group. More patients in CWM group needed extra force-air warming device when core temperature was less than 35?C. Pressure-heat burns were found in only CWM groups of five cases. Surgeons' satisfaction was not different between the groups. Conclusion: The present custom-made FWM with three appendages was superior to the CWM for preventing heat loss in vascular surgery.