Objectives: This meta-analysis compared the earliest clinical effects of intra-articular bupivacaine and morphine for pain management following arthroscopic knee surgery.
Materials and methods: A comprehensive literature search was conducted using MEDLINE (1966 to 2013), the Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and Google Scholar databases for identification of randomized-controlled trials that compared IA bupivacaine and morphine for postoperative pain. The relative risk, weighted mean difference (WMD), and their corresponding 95% confidence intervals (CI) were calculated using RevMan statistical software.
Results: Bupivacaine and morphine group had similar acute postoperative pain scores (WMD: 0.07; 95% CI, -0.18 to 0.32; P=0.60); number of patients requiring supplementary analgesia (relative risk: 0.74; 95% CI, 0.42 to 1.31; P=0.30) for the trials in this meta-analysis (n=13); and side effects (relative risk: 0.63; 95% CI, 0.39 to 1.02, P=0.06). Even though, the time to first analgesic request resulted in a significant difference (WMD: 66.59; 95% CI, 11.75 to 122.14, P=0.02), this result was not supported by the sensitivity analysis.
Conclusions: On the basis of the currently available literature, this study failed to demonstrate a significant difference between single-dose intra-articular bupivacaine and morphine at the end of the arthroscopic knee surgery in terms of pain relief, need for supplementary analgesics, times interval before the first request for additional analgesic, and short-term side effects.
Level of evidence: Level II-meta-analysis of Level I and II studies.