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

Assem Adel Moharram,Raham Hasan Mostafa

doi:10.2174/2589645801913010068

Abstract

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.

Highlights

Perioperative hemodynamic stability is the cornerstone step during spine surgery
The two groups were similar as regards: age, sex, weight, BMI and American Society of Anesthesiologist (ASA) physical status (Table 2)
The 2 groups were similar with respect to the duration of the surgical operation (199.3 ± 18.65 min versus 200.6 ± 20.66), intraoperative blood loss (620 ± 129.1 mL versus 610 ± 150.6 mL), number of patients who received blood intraoperatively (15 out of 30 versus 14 out of 30); all in control group versus dexmedetomidine group, respectively (Table 3)

Summary

Introduction

Perioperative hemodynamic stability is the cornerstone step during spine surgery. During surgery, low arterial pressure predisposes patients to spinal cord ischemia, on the other hand, a sudden rise in arterial pressure can cause bleeding in the surgical field and render surgical difficulties. Maintaining a clear surgical field helps surgeons to reduce surgery time, which in turn reduces the total blood loss and improving postoperative surgical outcome. Dexmedetomidine in its known dose range of 0.2 to 0.7 μg/kg/hour has a rapid onset, with a half-life of distribution of around 6 minutes and elimination half-life of 2 hours [2]. It elicits a biphasic blood pressure response: A short hypertensive phase followed by hypotension. This study was intended to evaluate the efficacy of dexmedetomidine infusion “without loading dose” as an effective hypotensive agent in lumbar fixation surgery

Methods

Results

Discussion

Conclusion