Background and Aim: This study was done to compare the efficiency of Dexmedetomidine and Esmolol in inducing deliberate hypotension and providing a better surgical field exposure during middle ear surgery. Parameters like MAP,HR and blood loss are compared between both the drugs.

Materials and Methods: This present study included patients aged between 18 to 60 years of ASA physical status I or II, who are planned to undergo a microscopic operation in the middle ear with informed consent. These were divided into Dexmedetomidine(D) group of 30 patients and Esmolol (E) group of 30 patients. Patients in the dexmedetomidine group (D) received a loading dose of 1 μg/kg of dexmedetomidine in 200 ml of 0.9% normal saline, before induction over 10 mins and subsequent maintenance doses of 0.5 μg/kg/h after intubation throughout the surgery. Whereas, patients in esmolol group(E) received a loading dose of 1 mg/kg of esmolol, before induction over 1 min and subsequent maintenance doses at 0.5 mg/kg/h after intubation throughout the surgery. Then, patients are evaluated for  hemodynamics like MAP,HR at regular intervals and blood loss noted for both drugs.

Results: Mean arterial pressure values were significantly decreased in Group D compared to that in Group E, except for the baseline value (p < 0.05). Blood loss is 104.15 ml in Dexmedetomidine group and 113.24 ml in Magnesium sulfate group, that is significantly low in Dexmedetomidine, hence quality of the surgical field and surgeon satisfaction score was better with D group at all intervals.Heart rate is significantly low in the Dexmedetomidine group at all intervals. Bradycardia is more prominent with Dexmedetomidine, with no major differences between other side effects.

Conclusion: Dexmedetomidine can provide more effective controlled hypotension and thus contribute to improved visibility of the surgical site.

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Sowdamini Teki

Post Graduate Student, Department of Anesthesiology, AMC, Visakhapatnam, Andhra Pradesh