Pain relieving effect of dexmedetomidine in patients undergoing total knee or hip arthroplasty: A meta-analysis

BACKGROUND: To evaluate the safety and efficacy of dexmedetomidine in patients undergoing total knee and hip arthroplasty for postoperative pain control. METHODS: An updated systematic review and meta-analysis of randomized controlled trials (RCTs) identified in systematic searches of MEDLINE, EMBASE, Google Scholar, the Cochrane Database and the Chinese SinoMed Database. RESULTS: Fourteen RCTs with a total of 1220 patients were included. Overall, dexmedetomidine therapy was associated with significantly decreased pain scores 24 hours after surgery (WMD, −0.36; 95% CI, −0.49 to −0.22; I(2) = 90.0%, P < .001) compared with scores in the control group after total hip arthroplasty (THA) and total knee arthroplasty (TKA). Furthermore, the rate of postoperative delirium was also markedly decreased with dexmedetomidine therapy (RR, 0.38; 95% CI, 0.24 to 0.59; I(2) = 0.0%, P < .001). Moreover, compared with the control group, dexmedetomidine treatment was associated with a decreased risk of postoperative nausea and vomiting in patients undergoing TKA (RR, 0.34; 95% CI, 0.15 to 0.79; I(2) = 0.0%, P = .012), and there was a similar risk of hypotension (RR, 1.03; 95% CI, 0.72 to 1.49; I(2) = 24.4%, P = .87) regardless of whether patients underwent TKA or THA. However, the rate of bradycardia was significantly increased with dexmedetomidine treatment in those undergoing TKA (RR, 6.11; 95% CI, 2.35 to 15.91; I(2) = 0.0%, P < .001). CONCLUSIONS: Dexmedetomidine therapy seems to be an effective treatment for pain control and postoperative delirium in patients undergoing TKA/THA. However, the incidence of bradycardia is markedly increased in patients undergoing TKA. Hence, much larger prospective clinical studies are warranted to confirm these findings.