Local infiltration with NSAIDs for postoperative analgesia: evidence for a peripheral analgesic action.

Abstract

In order to investigate the evidence for a peripheral analgesic effect of local infiltration with nonsteroidal antiinflammatory drugs (NSAIDs) in postoperative pain, we conducted a systematic review. Randomised controlled and double-blind trials were evaluated. Outcome measures were pain scores, the use of supplementary analgesics, 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 pain scores between treatment groups. Sixteen studies with data from 844 patients were considered appropriate for analysis. The NSAIDs were administered as intra-articular injections, as components of intravenous regional anaesthesia (IVRA), and by wound infiltration and were compared with systemic administration or placebo. In the four studies comparing intra-articular NSAIDs with systemic administration a statistically significant effect in favour of intraarticular NSAIDs was found. Only one study compared IVRA NSAID with systemic administration, showing a significant effect in favour of IVRA administration. No more than two of the five studies comparing intrawound NSAIDs with systemic administration showed significant effect after intrawound administration. Most of the studies comparing local infiltration with placebo showed significant effect in favour of local infiltration. There is evidence for a clinically relevant peripheral analgesic action of intra-articular NSAIDs while results of IVRA and wound infiltration with NSAIDs in postoperative pain are inconclusive. Trials without a systemic control group were not considered to provide evidence for a local effect.