RESUMO
OBJECTIVE: Residual carbon dioxide contributes substantially to pain following laparoscopic surgery. We evaluated the effects of extended assisted ventilation (EAV) with an open umbilical trocar valve for five additional minutes following laparoscopic hysterectomy on postoperative abdominal and shoulder pain levels. We also examined whether a combination of EAV and trocar site infiltration (TSI) with lidocaine could further reduce postoperative pain levels. STUDY DESIGN: In this prospective randomized trial, the effectiveness of EAV and EAV/TSI in reducing postoperative abdominal and shoulder pain were compared with that of a standard treatment regime in 283 patients undergoing laparoscopic hysterectomy (total or supracervical). Pain levels were evaluated by self-assessment questionnaire using a numeric rating scale (NRS) and by postoperative piritramid requirement, a surrogate parameter for postoperative analgesic drug requirement. The incidence of nausea and vomiting was also assessed. RESULTS: Compared with the standard treatment regime, EAV reduced abdominal pain levels significantly at 3h (NRS score, 3.21 ± 1.56 vs. 4.73 ± 1.71) and 24h (3.82 ± 1.49 vs. 4.95 ± 1.68) postoperatively (both p < 0.01). EAV also significantly reduced shoulder pain at 24h (EAV vs. control, 4.28 ± 1.51 vs. 5.14 ± 1.49) and 48 h (3.64 ± 1.66 vs. 4.22 ± 1.43) postoperatively (both p < 0.01). Patients in the EAV group had significantly lower piritramid requirements compared with standard treatment at 3h post-operatively (4.28 ± 2.09 mg vs. 6.31 ± 2.21 mg; p<0.01). EAV/TSI showed no additional benefit in terms of pain reduction compared with EAV alone. Incidences of postoperative nausea and vomiting were not reduced by EAV or EAV/TSI. CONCLUSION: EAV was found to be an effective and safe method to reduce postoperative pain levels in patients undergoing laparoscopic hysterectomy.