What influence does intermittent pneumatic compression of the lower limbs intraoperatively have on core hypothermia?

Background: Intermittent pneumatic compression (IPC) devices have been widely used for thrombosis prophylaxis in laparoscopic colorectal surgery. However, periodic compression using an IPC device may inject augmented boluses of cool blood from the lower limbs into the central circulation repetitively, thereby causing a reduction in core temperature. The authors therefore conducted a prospective, randomized, double-blind, controlled study to compare the effects of intraoperative IPC on core temperature in patients undergoing laparoscopic colorectal surgery. Methods: For this study, 56 patients ages 18-60 years and scheduled to undergo laparoscopic resection for colorectal cancer under general anesthesia were randomly assigned to receive either no IPC (control group) or calf-thigh-length IPC in both legs using the SCD Express (IPC group). Anesthetic, thermal, and pneumoperitoneum management were standardized. Esophageal temperature, as an indicator of core temperature, was measured at 15-min intervals for 2 h after induction of anesthesia. Results: A total of 47 subjects (23 control and 24 IPC subjects) were included in the analysis. The core temperature drop in the IPC group was significantly greater than in the control group, starting from 45 min after induction of anesthesia (P < 0.05). As a result, the total temperature drop during the 2-h study period was significantly greater in the IPC group (1.2 ± 0.3 C) than in the control group (0.9 ± 0.3 C) (P = 0.004). Conclusions: Because intraoperative application of IPC carries an increased risk of a core temperature drop, appropriate temperature monitoring and active thermal management are required for surgical patients receiving IPC.