Pharmacological Interventions for the Treatment and Control of Shivering in Adult Patients Undergoing Elective Surgery Under Regional Anaesthesia: A Systematic Review and Meta-Analysis

Intraoperative shivering is quite common after regional anaesthesia, which not only increases the total body oxygen requirement but also causes discomfort to the patients. The aim of this systematic review is to determine the effectiveness of pharmacological agents administered intra-operatively for treating shivering in adult patients who are undergoing elective surgery under regional (i.e., central neuraxial) anaesthesia so that an optimal choice of an agent can be recommended for clinical application. A literature search was carried out using PubMed, Cochrane Library, CINAHL databases, and hand searches to identify relevant studies. After literature screening and information extraction, a systematic review was performed. Meta-analysis was performed for the primary outcome. The primary outcome was to evaluate the effectiveness of pharmacological agents used for the treatment and control of intraoperative shivering and the time taken to control shivering. The secondary outcome includes recurrence of shivering after pharmacological intervention and identification of common adverse effects related to them. In total, 10 studies (791 patients) were included. Common interventions were opioids, central alpha 2 receptor agonist, and few other medications like magnesium sulfate, ondansetron, nefopam, and amitriptyline. Tramadol and dexmedetomidine were the most frequently documented drugs compared with other drugs to resolve shivering. The most effective drug with approximately 100% response rate was dexmedetomidine with the dose of 0.5 mu g kg(-1) intravenously given just after the appearance of shivering. Studies showed that tramadol is also an effective drug used to control shivering in most patients, and its effect is comparable with the pethidine.