The abdominal compliance index and postoperative pain after laparoscopic gynecologic surgery: a preliminary observational cohort study.

Background/aim: In gynecology, laparoscopic surgery has the advantages of reduced scarring, less postoperative pain, faster recovery, and lower risk of complications. Despite these advantages, shoulder pain still remains a major concern, affecting up to 90% of patients undergoing gynecologic laparoscopic surgery. Use of the abdominal compliance index (ACI) may offer the benefit of increased space for safer surgery and may prevent the drawback of high insufflation pressures. The aim of this study was to investigate the relationship between shoulder pain, abdominal pain, and analgesic use with the recently advised ACI, a surrogate index of abdominal expansion in patients undergoing gynecologic laparoscopic surgery.

Materials and methods: Thirty-one patients with American Society of Anesthesiologists scores of 1-3 who underwent elective gynecologic laparoscopic surgery were included. The insufflation pressure was set to 12 mmHg. ACI, defined as insufflated intraabdominal volume (L) per body surface area (m²), was used to estimate the relationship between abdominal compliance and postoperative pain.

Results: The 31 patients were separated into two groups based on median ACI level (range 1.37-2.73 L/m²), with those having values of 2.16 L/m² or lower as group 1 and those with higher values as group 2. Abdominal visual analogue scale (VAS) scores at 30 min postoperative were significantly higher in group 2 than in group 1 (p < 0.001). Shoulder pain VAS scores at 24 h and 36 h postoperative were also significantly higher in group 2 than in group 1 (p = 0.021 and p = 0.002, respectively). The total amount of analgesic infusion and additional analgesic requirements were lower in group 1 than in group 2 (p = 0.049 and p = 0.001, respectively). ACI did not differ with patient demographic characteristics or history of abdominal/laparoscopic surgery, parity, abdominal drainage, and pneumoperitoneum time.

Conclusion: ACI, a surrogate index of abdominal expansion capacity, may be used to guide individualization of insufflation pressures by identifying female patients under risk of higher postoperative pain.