Dexamethasone reduces pain, vomiting and overall complications following tonsillectomy in adults: a systematic review and meta-analysis of randomised controlled trials

Background: Tonsillectomy is one of the most common surgical procedures, but there is debate whether systemic steroids should be used to reduce pain and post-operative complications. Objective of review: To determine whether perioperative steroids reduce post-tonsillectomy pain and complications in adults. Type of review: Systematic review and meta-analysis of randomised controlled trials. Search strategy: We searched MEDLINE (1950-2010), EMBASE (1980-2010), CINAHL (1981-2010), Web of Science, ProQuest, metaRegister, Conference Proceedings Citation Index, the Cochrane Library and reference lists of relevant studies. Evaluation method: Two reviewers independently selected trials and extracted data on their quality, characteristics and results. Trials included adults (age > 16 years) undergoing elective tonsillectomy where peri-operative steroids were used, and the results were compared with control or placebo. Results: There were seven randomised controlled trials (580 patients) reporting post-operative pain. Meta-analysis demonstrates that dexamethasone in adults reduces the pain level experienced in the first post-tonsillectomy day [standard mean difference (SMD): -0.63, 95% CI: -1.13 to -0.12] with significant heterogeneity (I-2 = 84%, P < 0.00001). Sub-group analysis to explore heterogeneity demonstrated this reduction in pain was mostly with high total dose steroids (total >10 mg over first 24 h postoperatively; SMD: -1.48, 95% CI: -2.17 to -0.79, P < 0.00001), especially when given both intra-operatively and post-operatively. There was no significant effect with low doses (SMD: -0.12, 95% CI: -0.36 to 0.13, P = 0.35). There were three trials (231 patients) that reported post-operative nausea and vomiting, three other trials (270 patients) reporting on bleeding and three trials (401 patients) reporting other complications (infections and odynophagia). There was a significant reduction in post-operative nausea and vomiting (RR: 0.53, 95% CI: 0.36 to 0.80, P = 0.002, I-2 = 26%) and bleeding (RR: 0.45, 95% CI: 0.25 to 0.80, P = 0.007, I-2 = 0%), but the reduction in the other complications did not reach statistical significance (RR: 0.69, 95% CI: 0.48 to 1.01, P = 0.06, I-2 = 0%). Pooling of these complications (postoperative nausea and vomiting, bleeding, infections and odynophagia) shows that in six trials (501 patients), the use of dexamethasone significantly reduced post-operative complications following tonsillectomy in adults (RR: 0.59, 95% CI: 0.49 to 0.71, P < 0.00001, I-2 = 0%), when compared with placebo or control. Conclusions: Dexamethasone reduces pain, postoperative nausea and vomiting, bleeding and overall postoperative complications in adults undergoing tonsillectomy. However, the effect of the dose of dexamethasone on post-operative pain and whether dexamethasone reduces bleeding require further research.