Effect of a low-dose dexmedetomidine infusion on intraoperative hemodynamics, anesthetic requirements and recovery profile in patients undergoing lumbar spine surgery

BACKGROUND AND AIMS: Dexmedetomidine has been used as an anesthetic adjuvant; however, hypotension is a concern especially in prone patients. The aim of the study was to evaluate the effect of a low-dose dexmedetomidine infusion on intraoperative hemodynamics, blood loss, anesthetic requirements, and recovery profile in patients undergoing lumbar spine surgery in the prone position. MATERIAL AND METHODS: The study was conducted in a randomized double-blinded manner in 60 patients scheduled for one- or two-level lumbar laminectomy. After administration of general anesthesia, patients were placed in prone position and allocated to either of two groups of 30 patients each. Patients in Group A received dexmedetomidine infusion at the rate of 0.3 μg kg(-1) hr(-1), whereas, group B patients received a saline infusion. The depth of anesthesia was guided by Bispectral index (BIS) monitoring, maintaining BIS between 40 and 60. RESULTS: The demographic profile and duration of surgery in both groups were similar. Mean heart rate was statistically similar in both the groups. Mean blood pressure was lower in group A, though the difference was significant only for the initial 30 min. The mean end-tidal sevoflurane requirement in group A was significantly less than that in group B (P = 0.003). Patients in group A had better recovery profile with mean emergence, extubation, and recovery times of 8.08 ± 3.48 min, 9.37 ± 3.64 min, and 11.65 ± 4.03 min, respectively, as compared with 11.27 ± 3.05 min, 12.24 ± 2.39 min, and 14.90 ± 2.63 min, respectively, in group B (P < 0.001). Mean intraoperative blood loss in group A of 263.47 ± 58.66 mL was significantly lower than 347.67 ± 72.90 ml in group B (P = 0.0001). CONCLUSION: Group A patients had stable hemodynamic parameters, reduced intraoperative blood loss, less anesthetic requirement, and could be extubated earlier as compared with group B patients.