Role of dexmedetomidine infusion after coronary artery bypass grafting

Postoperative pain has negative consequences on patients' outcomes after cardiac surgery. Routine management with opioid and or non-steroidal anti-inflammatory medications has several disadvantages. Dexmedetomidine is a selective α2 agonist used for sedation and analgesia. The use of dexmedetomidine for postoperative pain management and decreasing delirium and agitation in cardiac surgery patients is a matter of debate. Our objective was to determine the role of an early administration of dexmedetomidine in decreasing opioid use post-cardiac surgery and its effects on the quality of postoperative recovery.

Medical records of 120 patients admitted to the cardiac surgery intensive care unit (CSICU) after coronary artery bypass grafting (CABG) in two cardiac centers between December 2015 and December 2016 were reviewed. Patients were divided into two groups. Group A included 55 patients who received dexmedetomidine in a dose of 0.2-0.4 mcg/kg/h on admission to CSICU, and group B included 65 patients who did not receive dexmedetomidine. The primary outcome was the pain score immediately after extubation, and the secondary outcomes included post-extubation sedation and pain scores for 12 h.There were significant decrease of the pain scores in dexmedetomidine group that continues through the 3rd, 6th, 8th, and 12th hour readings after surgery with mean modified Ramsay scores 0.1 ± 0.0, 0.89 ± 2.05, 0.35 ± 0.1, and 0.12 ± 1.1 respectively compared to 0.46 ± 1.15, 3.46 ± 2.93, 0.98 ± 1.90, and 0.12 ± 1.1 in group B (p < 0.001), significant decrease in cumulative morphine received (p < 0.001, OR = 909, 95% CI 0.05-0.19), favorable reduction in heart rate in dexmedetomidine group (80 ± 1.9 b/min) compared to 96 ± 8.8 b/min in the other group (p = 0.017), and smoother recovery from general anesthesia.

Administration of dexmedetomidine in the early postoperative period can be safe. It may reduce the use of opioids, has sedative, analgesic, and sympatholytic effects that could play a useful role during the management of coronary artery bypass patients, and may improve postoperative recovery.