Comparative Evaluation of Different Doses of Intravenous Dexmedetomidine on Hemodynamic Response during Laryngoscopy and Endotracheal Intubation in Geriatric Patients Undergoing Spine Surgeries: A Prospective, Double-Blind Study.

Background: Dexmedetomidine, a selective alpha 2 (α2 )-adrenergic receptor agonist, has been used to blunt the hemodynamic response associated with laryngoscopy and tracheal intubation, which is a common concern for the anesthesiologist, especially in high-risk patients and geriatric age group.

Aim and Objectives: The current study is to evaluate and compare the effects of different doses of dexmedetomidine in controlling hemodynamic response during tracheal intubation in geriatric patients.

Materials and Methods: After getting approval from the Ethical Committee, 90 patients of the American Society of Anesthesiologist Physical Status Classes I and II, aged ≥60 years, were randomly assigned into three groups: Group I (normal saline, n = 30), Group II - dexmedetomidine (0.50 μg/kg, n = 30), and Group III - dexmedetomidine (1.00 μg/kg, n = 30). Dexmedetomidine was infused for 10 min before induction. Data were recorded as before infusion (T0), at the end of infusion (T1), before tracheal intubation (T2), at the moment of tracheal intubation (T3) 5 min after tracheal intubation (T4), and 10 min after tracheal intubation (T5). Modified observer's assessment of alertness/sedation scale score was observed at the time of T0 and T1. All statistical analyses were done using SPSS version 22.

Results: Mean systolic blood pressure was statistically significantly ( P < 0.05) more among Group I compared to Group II and III at T2, T3, and T4. Mean heart rate (HR) value was significantly ( P < 0.05) more among Group I compared to Group III from T1 to T5, whereas there was no significant change in HR between Group I and Group II and at T4 and T5 h was comparable in Group II and Group III.

Conclusion: This study concluded that more acceptable hemodynamic changes were seen with 0.50 μg/kg dexmedetomidine when compared with 1.0 μg/kg dexmedetomidine during intubation. A lower dose besides being cost-effective is also free of side effects associated with the higher dose of 1 μg/kg dexmedetomidine.