Effect of Morphine Versus Low and High Dose Dexmedetomidine on Postoperative Stress Response in Patients Undergoing Cancer Surgeries

Background: Dexmedetomidine, a selective α2 adrenore-ceptor agonist, is widely used in various clinical settings for its sympatholytic, sedative, anesthetic sparing and hemody-namic stabilizing properties without significant respiratory depression. Methods: Eighty four cancer patients scheduled for cancer surgeries under general anesthesia were randomized blindly into three parallel groups in this prospective study: Low dose dexmedetomidine group (group A, n=28) received 30 minutes before the anticipated end of surgery a loading dose of dexme-detomidine 1propto g/kg in 100mL of normal saline over 20 minutes then an infusion of 0.5propto g/kg/hour for 48 hours, high dose dexmedetomidine group (group B, n=28) received 30 minutes before the anticipated end of surgery a loading dose of dexme-detomidine 1propto g/kg in 100mL of normal saline over 20 minutes then an infusion of 1propto g/kg/hour for 48 hours, morphine group (group C, n=28) received immediately postoperative IV morphine as 0.1mg/kg as bolus dose and then continuous IV infusion at rate of 0.02mg/kg/hour for 48 hours. Stress response was assessed by random blood sugar (RBS) and serum cortisol level which was measured 8 hours postoperatively at 1st day and at the same time at 2nd postoperative day. Sedation was assessed at 30min and then every 4 hours for 48 hours. Results: RBS and serum cortisol showed no significant increase among the three groups. During the whole 48 hours postoperatively, group C significantly had lower sedation score than group A and B. Conclusion: The results of this study proved that dexmedetomidine (low and high dose) has sedation and alleviates stress response in the form of lowering blood glucose and serum cortisol.