Pneumoperitoneum pressures during pelvic laparoscopic surgery: a systematic review and meta-analysis.

Growing evidence suggests that the level of pneumoperitoneal pressure is directly correlated with postoperative pain in patients undergoing laparoscopic procedures. However, only limited evidence is available in the field of gynaecologic surgery. Therefore, this study aimed to compare the effects of low (8mmHg), standard (12mmHg) and high (15mmHg) pneumoperitoneal pressures (LPP<SPP and HPP, respectively) during laparoscopic procedures confined to the pelvis. The primary outcome was to evaluate if changes in pneumoperitoneal pressure influence postoperative pain. The study also sought to determine the safety of LPP during gynaecologic procedures. A literature search revealed two randomized controlled trials that evaluated the effects of different pneumoperitoneal pressures. Overall, 230 patients who underwent gynaecologic procedures via laparoscopy using different pneumoperitoneal pressures (LPP: n=74, 32%; SPP: n=67, 29%; HPP: n=89, 39%) were evaluated. Pooled results suggested that the use of LPP does not increase operative time compared with SPP [mean difference (MD) 6.78min] and HPP (MD 5.52min). Similarly, no differences in operative time were recorded between procedures using SPP and HPP (MD 0.34min). Estimated blood loss was not influenced by CO2 intra-abdominal pressure (LPP vs SPP: MD 10.05ml; LPP vs HPP: MD -4.03ml; SPP vs HPP: MD 6.75ml). Twenty-four hours after surgery, HPP was found to be correlated with higher levels of pain compared with LPP and SPP. However, CO2 pressure did not influence the length of hospital stay. These results suggest that in comparison with SPP and HPP, LPP provides a slight benefit in terms of postoperative pain among patients undergoing gynaecologic laparoscopy, with no increase in operative time, blood loss or surgery-related morbidity.