Pharmacological interventions for prevention or treatment of postoperative pain in people undergoing laparoscopic cholecystectomy.

backgroundWhile laparoscopic cholecystectomy is generally considered less painful than open surgery, pain is one of the important reasons for delayed discharge after day-surgery and overnight stay following laparoscopic cholecystectomy. The safety and effectiveness of different pharmacological interventions such as non-steroidal anti-inflammatory drugs, opioids, and anticonvulsant analgesics in people undergoing laparoscopic cholecystectomy is unknown.

objectivesTo assess the benefits and harms of different analgesics in people undergoing laparoscopic cholecystectomy. SEARCH

methodsWe searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization International Clinical Trials Registry Platform portal (WHO ICTRP) to March 2013 to identify randomised clinical trials of relevance to this review. SELECTION CRITERIA: We considered only randomised clinical trials (irrespective of language, blinding, or publication status) comparing different pharmacological interventions with no intervention or inactive controls for outcomes related to benefit in this review. We considered comparative non-randomised studies with regards to treatment-related harms. We also considered trials that compared one class of drug with another class of drug for this review. DATA COLLECTION AND ANALYSIS: Two review authors collected the data independently. We analysed the data with both fixed-effect and random-effects models using Review Manager 5 analysis. For each outcome, we calculated the risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI). MAIN

resultsWe included 25 trials with 2505 participants randomised to the different pharmacological agents and inactive controls. All the trials were at unclear risk of bias. Most trials included only low anaesthetic risk people undergoing elective laparoscopic cholecystectomy. Participants were allowed to take additional analgesics as required in 24 of the trials. The pharmacological interventions in all the included trials were aimed at preventing pain after laparoscopic cholecystectomy. There were considerable differences in the pharmacological agents used and the methods of administration. The estimated effects of the intervention on the proportion of participants who were discharged as day-surgery, the length of hospital stay, or the time taken to return to work were imprecise in all the comparisons in which these outcomes were reported (very low quality evidence). There was no mortality in any of the groups in the two trials that reported mortality (183 participants, very low quality evidence). Differences in serious morbidity outcomes between the groups were imprecise across all the comparisons (very low quality evidence). None of the trials reported patient quality of life or time taken to return to normal activity. The pain at 4 to 8 hours was generally reduced by about 1 to 2 cm on the visual analogue scale of 1 to 10 cm in the comparisons involving the different pharmacological agents and inactive controls (low or very low quality evidence). The pain at 9 to 24 hours was generally reduced by about 0.5 cm (a modest reduction) on the visual analogue scale of 1 to 10 cm in the comparisons involving the different pharmacological agents and inactive controls (low or very low quality evidence). AUTHORS'

conclusionsThere is evidence of very low quality that different pharmacological agents including non-steroidal anti-inflammatory drugs, opioid analgesics, and anticonvulsant analgesics reduce pain scores in people at low anaesthetic risk undergoing elective laparoscopic cholecystectomy. However, the decision to use these drugs has to weigh the clinically small reduction in pain against uncertain evidence of serious adverse events associated with many of these agents. Further randomised clinical trials of low risk of systematic and random errors are necessary. Such trials should include important clinical outcomes such as quality of life and time to return to work in their assessment.