Effects of low intraperitoneal pressure and a warmed, humidified carbon dioxide gas in laparoscopic surgery: a randomized clinical trial

Abstract

Laparoscopic surgery technology continues to advance. However, much less attention has been focused on how alteration of the laparoscopic surgical environment might improve clinical outcomes. We conducted a randomized, 2 × 2 factorial trial to evaluate whether low intraperitoneal pressure (IPP) (8 mmHg) and/or warmed, humidified CO₂ (WH) gas are better for minimizing the adverse impact of a CO₂ pneumoperitoneum on the peritoneal environment during laparoscopic surgery and for improving clinical outcomes compared to the standard IPP (12 mmHg) and/or cool and dry CO₂ (CD) gas. Herein we show that low IPP and WH gas may decrease inflammation in the laparoscopic surgical environment, resulting in better clinical outcomes. Low IPP and/or WH gas significantly lowered expression of inflammation-related genes in peritoneal tissues compared to the standard IPP and/or CD gas. The odds ratios of a visual analogue scale (VAS) pain score >30 in the ward was 0.18 (95% CI: 0.06, 0.52) at 12 hours and 0.06 (95% CI: 0.01, 0.26) at 24 hours in the low IPP group versus the standard IPP group, and 0.16 (95% CI: 0.05, 0.49) at 0 hours and 0.29 (95% CI: 0.10, 0.79) at 12 hours in the WH gas group versus the CD gas group.

Figure 1

CONSORT diagram.

Figure 2

Odds ratios (A and B) of a VAS pain score of >30 in the ward. ^aOdds ratios when comparing the 8-mmHg group relative to the 12-mmHg group. ^bOdds ratios when comparing the WH group relative to the CD group. Number of patients. 12-mmHg group: n = 41 at 0 hours, n = 41 at 12 hours; n = 41 at 24 hours. 8-mmHg group: n = 41 at 0 hours, n = 41 at 12 hours; n = 41 at 24 hours. CD group: n = 42 at 0 hours, n = 42 at 12 hours; n = 42 at 24 hours. WH group: n = 40 at 0 hours, n = 40 at 12 hours; n = 40 at 24 hours.