The Effect of Pre-Emptive Dexmedetomidine on the Incidence of Post-Thoracotomy Pain Syndrome in Patients Undergoing Coronary Artery Bypass Grafting

BACKGROUND: Post-thoracotomy pain syndrome (PTPS) is pain that recurs or persists along a thoracotomy incision for at least two months following surgery. Dexmedetomidine (dex) is an α-2 agonist that also has analgesic, sedative-hypnotic, and sympatholytic properties. OBJECTIVES: To determine the effect of pre-emptive dexmedetomidine on the incidence of PTPS in patients undergoing coronary artery bypass grafting (CABG). PATIENTS AND METHODS: This randomized clinical trial enrolled 104 candidates for elective coronary artery bypass grafting (CABG) and randomly assigned them to either a dex group or a control group. In the dex group, dexmedetomidine 0.5 µg/kg/hour was infused from the initiation of anesthesia until postoperative extubation in the intensive-care unit. Two months after surgery, the patients were contacted by telephone and interviewed to determine the presence of pain at the thoracotomy scars. RESULTS: Fifty-four patients were placed in the control group, and 50 patients were assigned to the dex group. The age, sex, and body mass index were not significantly different between the two groups of study (P > 0.05). The incidence of PTPS was 11/50 (22%) patients in the dex group and 28/54 patients (52%) in the control group. A chi-square test revealed a significant difference in the incidence of PTPS after two months between the dex and control groups (P = 0.032). CONCLUSIONS: PTPS is a common problem following CABG, and pre-emptive therapy with dex may decrease neuropathic pain.