Objective:

We aimed to compare the effects of esmolol (ß-blocker) and dexme-detomidine (α-2-agonist) on patients’ clinical course and cost for controlled hypotension during middle-ear surgery.

Methods:

Fifty patients with ASA I-II scheduled for tympano-mastoidectomy were enrolled in the study and randomized into 2 similar groups. Bispectral Index (BIS)and neuromuscular monitoring (TOF GUARD-SX) were applied to all patients. In group E (n=25), 0.5 mg kg-1 min-1 esmolol was infused over 1 min before induction and titrated over a range of 10- 200 μg kg-1 min-1; in group D (n=25), 0.5 μg kg-1 dexmedetomidine was infused over 10 minutes before induction, and then titrated over a range of 0.2-0.7 μg kg-1 hr-1 to maintain mean arterial pressure (MAP) between 55 and 65 mmHg after induction. In both groups, 0.25 μg kg-1 min-1 remifentanil infusion was used for maintenance with 1 MAC sevoflurane in 50% O2 +50% air mixture so that BIS was kept between 40 and 50. In both groups, effects on haemodynamics (heart rate (HR), mean arterial pressure (MAP)), neuromuscular blockage (onset of action (OA), duration of clinical action (DCA), recovery index (RI)), bleeding score, surgeon satisfaction, and the total quantity of dexmedetomidine and esmolol doses were recorded and the costs were compared.

Results:

No significant difference was present in haemodynamics, bleeding scores or surgeon satisfaction between groups. Although OA was similar in both groups, DCA and RI were significantly higher in group D. Cost was significantly higher with esmolol than dexmedetomidine.

Conclusion:

We conclude that both agents are feasible. However, a prolongation in neuromuscular block time was found with dexmedetomidine, while higher costs were observed with esmolol.

Keywords: Anesthesia, esmolol, dexmedetomidine, controlled hypotension, middle ear surgery