Local anesthetic infiltration for postoperative pain relief after laparoscopy: A qualitative and quantitative systematic review of intraperitoneal, port-site infiltration and mesosalpinx block

In a systematic review, we evaluated randomized controlled trials (RCTs) of peripheral local anesthetics (LA) compared with placebo or no treatment in the control of postoperative pain after laparoscopic surgery. A total of 4 1 trials with data from 2794 patients were considered appropriate for analy sis. Of these 41 RCTs, 13 evaluated intraperitoneal LA after cholecystectom y, four RCTs assessed intraperitoneal LA after other procedures, eight RCTs evaluated port-site infiltration after various procedures, 12 RCTs evaluat ed mesosalpinx or fallopian tube block after sterilization, and four RCTs c onsidered combined LA regimens. Outcome measures were pain scores, analgesi c consumption, and time to first analgesic request. Efficacy was estimated by significant difference (P < 0.05), as reported in the original reports, and by calculation of the weighted mean difference of visual analog scale p ain scores between treatment groups. Improved pain relief was observed in s even of the 13 RCTs of intraperitoneal LA after cholecystectomy and in four RCTs of other procedures. A statistically significant weighted mean differ ence of -13 mm visual analog scale (95% confidence intervals [CI]: -20 to - 6) in favor of the treatment groups was observed after cholecystectomy. Thr ee of eight trials of port-site infiltration showed significant differences but questionable clinical importance and validity in two; weighted mean di fference was not statistically significant between treatment groups (95% CI : -9 to 1). All RCTs of mesosalpinx or fallopian tube block after steriliza tion showed improved pain relief with a statistically significant weighted mean difference of -19 mm (95% CI: -25 to - 14) in favor of treatment group s. Data of combined regimens were positive, however, sparse. We conclude th at there was evidence for a statistically significant but clinically questi onable, important effect of intraperitoneal LA for postoperative pain contr ol. There was evidence for a significant but short-lasting effect of mesosa lpinx/fallopian tube block after sterilization, but there was a lack of evi dence for any important effect of port-site infiltration. Data from combine d regimens were too sparse for conclusions. Implications: A systematic revi ew summarizes, through transparent methodology, available information from randomized, controlled trials to produce the best available evidence-based estimate of a "true" clinical effect of an intervention. This systematic re view confirms intraperitoneal and mesosalpinx local anesthetic block, not p ort-site infiltration, to have some impact on postoperative pain after lapa roscopy.