Introduction: Postoperative pain is a significant problem in paediatric surgery. Inadequate analgesia increases patient distress in the short term and may have long-term adverse effects. The alpha-2 adrenergic agonist, clonidine, has been used as a premedication for anxiolysis, sedation, analgesia and reduction of heart rate and blood pressure. However, its use can result in excessive sedation, hypotension and bradycardia1. The overall benefits of clonidine as a premedication over other commonly used drugs, such as midazolam, have in recent years been the subject of review2 and meta-analysis3. This systematic review aims to evaluate the postoperative analgesia effects of clonidine premedication when compared to any other treatment, placebo or usual care. Methods: This study was conducted according to Cochrane methodology. We searched for randomised or quasi-randomised controlled trials of children <18 years presenting for general anaesthesia. We included any study where clonidine premedication was administered and compared with any other intervention or no treatment. Primary outcomes were: the requirement for supplementary analgesia, either in the post-anaesthesia care unit or subsequently, and excessive sedation requiring intervention. Secondary outcome measures included: pain scores, opioid use, haemodynamic outcomes and time until discharge from PACU and the hospital. Meta-analysis was performed using a random effects, Mantel-Haenszel model. Results: Database search found 179 studies of which 39 papers were retrieved in full. Ten studies investigating 729 children were subsequently found suitable for inclusion. Four compared clonidine with placebo or no treatment, five compared clonidine with midazolam and one compared clonidine premedication with fentanyl. Clonidine was associated with a non-significant reduction in the incidence of postoperative analgesia use in the three trials with data, suitable for meta-analysis, investigating this comparison - RR 0.28 (95% confidence interval 0.05, 1.45). There was a significant reduction in the one study comparing clonidine with midazolam presenting dichotomous data, RR 0.25 (95% confidence interval 0.12, 0.53). There was no difference in incidence of postoperative analgesia use in the one study comparing clonidine with fentanyl, RR 0.71 (95% confidence interval 0.18, 2.89). Conclusion: Preliminary findings suggest that clonidine decreased the incidence of postoperative analgesia use when compared with midazolam and possibly placebo or no treatment. However there was no difference in postoperative analgesia use when clonidine was compared with fentanyl.
P., L., N., K., P., M., & A., C. (2011). Clonidine premedication for postoperative analgesia in children: A meta-analysis. Anaesthesia and Intensive Care, 39(4), 714. Retrieved from http://www.embase.com/search/results?subaction=viewrecord&from=export&id=L70504493 http://www.aaic.net.au/Document/PDF.ashx?D=20110488 LK - http://DV9BS6ZB6V.search.serialssolutions.com/?sid=EMBASE&sid=EMBASE&issn=0310057X&id=doi:&atitle=Clonidine+premed