The Use of Intravenous Clonidine in Postoperative Pain Management: A Scoping Review

BACKGROUND: Clonidine, an alpha-2 receptor agonist, has been explored as a potential analgesic in postoperative pain management, but its efficacy and safety profile remain unclear. The aim of this scoping review was to present the evidence on the use of intravenous clonidine in postoperative pain management. METHODS: This scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. We searched the following databases: The Cochrane Library, Embase, and MEDLINE for studies investigating the use of intravenous clonidine in postoperative pain management, regardless of comparators or outcomes. Data were summarized and presented descriptively. Risk of bias was assessed using the Risk of Bias 2 tool for randomized trials, while the certainty of evidence was evaluated at the outcome level using a modified Grading of Recommendations Assessment, Development and Evaluation approach. RESULTS: We included 10 trials with a total of 646 patients. Most patients were ASA I-II and underwent major elective surgery. The trials varied in clonidine dosage, timing, and combination with other analgesics. All included trials reported outcome data for pain and/or supplemental analgesia with high variability in assessment strategies. The data showed inconsistent effects of clonidine in reducing pain scores and the need for supplemental analgesia. Reported adverse effects were also inconsistent across studies. The overall certainty of evidence was very low for all outcomes. CONCLUSION: Evidence for the use of intravenous clonidine in postoperative pain management is heterogeneous and limited, providing no consistent clinical benefit and underscoring the need for further research. EDITORIAL COMMENT: This scoping review presents the current evidence for intravenous clonidine for post-operative analgesia. So far there is not enough evidence to support a recommendation concerning if or how intravenous clonidine should be used in this context.