A Comparative Study of the Amount of Bleeding and Hemodynamic Changes between Dexmedetomidine Infusion and Remifentanil Infusion for Controlled Hypotensive Anesthesia in Lumbar Discopathy Surgery: A Double-Blind, Randomized, Clinical Trial

BACKGROUND: The aim of this study was to compare the volume of blood loss and hemodynamic changes in patients undergoing lumbar discopathy, after continuous infusions of dexmedetomidine versus remifentanil during anesthesia with controlled low blood pressure. METHODS: In this randomized double-blind clinical trial, 60 patients aged 20 to 65 years were randomly assigned to control and intervention groups. The intervention group received a continuous infusion of dexmedetomidine at 0.3 - 0.7 µg/kg/hour plus propofol at 50 - 100 µg/kg/minute. The control group was given a continuous infusion of remifentanil at 0.1 to 1 µg/kg/minute plus the same dose of propofol as above. The primary outcome was the amount of patient's bleeding during surgery, and secondary outcomes were changes in the patient's systolic blood pressure, diastolic blood pressure, mean arterial pressure, and urinary output. RESULTS: Univariate and multivariate analyses of the main outcome in the control and intervention groups showed that there was no significant difference between the two drugs with regards to the volume of blood loss, mean arterial pressure, and systolic and diastolic blood pressure. Postoperative side effects were significantly lower in the intervention group (P = 0.002). CONCLUSIONS: Administration of dexmedetomidine plus propofol in comparison with remifentanil plus propofol did not show any significant difference regarding blood loss and hemodynamic changes; however, it reduced some side effects after surgery and decreased analgesic requirement in the postoperative period. Taken together, the findings of this study do not support strong recommendations for dexmedetomidine infusion for all patients and the decision should be taken with caution on basis of the anesthesiologist’s expert opinion and the patient’s condition during surgery.