Does intra‐operative humidification with warmed CO₂ reduce surgical site infection in open colorectal surgery? A randomized control trial

Abstract

Backgrounds Surgical site infections (SSI) are a significant cause of postoperative morbidity and mortality, contributing to a considerable financial burden on the healthcare system. Insufflation of the open surgical wound with warm, humidified carbon dioxide (CO2) is a novel measure aimed to reduce SSI. The local atmosphere of warm, humidified CO2 within the open surgical wound is proposed to decrease airborne contamination, bacterial growth, desiccation, and heat loss while improving tissue oxygenation and perfusion. This randomized controlled trial evaluates the impact of the HumiGard™ surgical humidification system on the incidence of SSI in patients undergoing open colorectal surgery. Methods We conducted a multi‐site single‐blinded randomized control trial on patients undergoing elective or emergency laparotomy at a single tertiary Colorectal Surgery service. The primary outcome measure was the incidence of SSI, with secondary outcomes including ICU length of stay (LOS), total LOS and mean core temperature. Results Patients who received HumiGard™ had a lower incidence of SSI, although this did not reach statistical significance (4.5% for treatment group versus 13.0% for control group; P = 0.092). There was no significant difference in ICU LOS or total LOS between cohorts. The HumiGard™ group had a higher mean core temperature than the control at the end of surgery (P < 0.001). Conclusion The present study could not confirm that utilization of warm, humidified CO2 with HumiGard™ reduces SSI in open colorectal surgery. Further research is indicated to validate and extend these findings.

The role of warmed‐humidified carbon dioxide insufflation in colorectal surgery: A systematic review and meta‐analysis

“…A retrospective study examining patients undergoing laparoscopic colorectal surgery receiving either DC‐CO 2 versus WH‐CO 2 , observed that WH‐CO 2 decreased the incidence of SSI by 66% [49]. A subsequent RCT in open colorectal surgery found patients who received WH‐CO 2 had significantly higher mean core temperature at the end of the procedure and a lower incidence of SSI but this did not reach statistical significance [50]. The physiological mechanism underpinning this relationship is thought to occur due to the hypothermia induced peripheral vasoconstriction which lowers the partial pressure of oxygen in tissues and thus their immune function [49, 51].…”

“…noticed a significant decrease in infection rates with WH‐CO 2 , but pooled analysis among five studies demonstrated no clinically meaningful difference. In contrast to the RCT which reported reduced rates of SSI, our review consisted only of elective procedures and predominantly laparoscopic surgeries [50]. Therefore, results may not be generalisable to open and emergent colorectal procedures, and this can be an area of future study.…”

“…Minimal important difference set at MD ≥1.3.by 66%[49]. A subsequent RCT in open colorectal surgery found patients who received WH-CO 2 had significantly higher mean core temperature at the end of the procedure and a lower incidence of SSI but this did not reach statistical significance[50]. The physiological mechanism underpinning this relationship is thought to occur due to the hypothermia induced peripheral vasoconstriction which low-…”

Is there a role for warm humidified carbon dioxide insufflation in open abdominal surgery?

“…Few studies also measured postoperative outcomes such as surgical site infections, anastomotic leak, length of stay, and mortality, although no statistically significant differences were seen 5,17–20 . A recent randomized controlled trial revealed a reduction in surgical site infections from 13% in conventional open surgery to 4.5% in the warm humidified group, and although this was in accordance with laparoscopic studies (5.7% versus 13%), this result was not statistically significant ( P = 0.092) 19,21 …”

“…In concordance with its use in laparoscopic surgery, studies where warm humidification is used in open surgery also show promising results for maintaining intraoperative normothermia and minimizing peritoneal damage. In these studies, patients who received warm humidification had a greater average mean core temperature, end of surgery core temperature, and were less likely to become hypothermic at any time during the operation 17–19 . When this technique was utilized, peritoneal biopsies revealed a reduction in oxidative damage and apoptosis of cells, and maintenance of cell structure on microscopy 5,20 .…”