Meta-analysis of the effect of warm humidified insufflation on pain after laparoscopy

BACKGROUND: Studies on the use of warmed and humidified insufflation (WHI) in laparoscopic abdominal procedures to reduce pain have been inconclusive owing to small sample sizes. METHODS: An electronic database search identified all randomized controlled trials (RCTs) on adults undergoing elective laparoscopic abdominal surgery under general anaesthesia in which the exposure group had WHI and the control group had standard cold and dry carbon dioxide. The outcome measure was pain by visual analogue score or morphine usage. RESULTS: Seven RCTs were included. Patients in the WHI group experienced a significant reduction in pain score at 6 h (P = 0.006), 1 day (P = 0.010) and 3 days (P < 0.001) after operation, and in morphine usage on day 2 (P = 0.040). CONCLUSION: WHI reduces pain after laparoscopy.