Efficacy of Dexmedetomidine Infusion Without Loading Dose as a Potent Hypotensive Agent in Lumbar Fixation Surgery

Background: Dexmedetomidine on the basis of the previous literature can be considered a safe agent for controlled hypotension through its central and peripheral sympatholytic action. Its easy administration and absence of fatal side effect make it a near-ideal hypotensive agent. This study was intended to evaluate the efficacy of dexmedetomidine infusion “without loading dose” as an effective hypotensive agent in lumbar fixation surgery. Methods: In a double-blind study, a total of 60 patients aged 18-65 years, of both genders, belonging to the American Society of Anesthesiologist (ASA) class I - II scheduled for elective lumbar spine instrumentation were included and divided into: Control group (Group C) who received placebo and Dexmedetomidine group (Group D) who received Intravenous (IV) dexmedetomidine. The patients were compared primarily for intraoperative hemodynamics. Results: The study results showed that dexmedetomidine had successfully maintained target mean blood pressure of 65-70 mmHg and only 2 patients out of 30 required rescue therapy (both of propofol and NG). Also, dexmedetomidine had maintained heart rate stability than the control group from the 15thminute after positioning till the end of surgery (P-value < 0.001). Intraoperative fentanyl consumption was significantly low in Dexmedetomidine group 75 ± 25.43 µgversus169.64 ± 34.26 µg in Control group (P-value < 0.001). Finally, more post-operative sedation was noticed during the 1stpostoperative hour in dexmedetomidine group when compared to the control group (P-value < 0.001). Conclusion: Dexmedetomidine infusion without loading dose could be an effective and safe agent in achieving controlled hypotension in adults undergoing elective lumbar spine instrumentation surgery with limited side effects together with intraoperative opioid-sparing effect.