Hydroxyzine dihydrochloride premedication is a necessity for pediatric patients undergoing strabismus surgery: An observational prospective clinical trial

Abstract

Objective: In this single-blind, observational prospective trial we aimed to determine and compare the effect of premedication with hydroxyzine plus midazolam and midazolam alone on the incidence of Oculocardiac Reflex (OCR).Methods: Forty-five patients divided into three groups retrospectively after surgery; according to the oral premedication before surgerys. Group M received 0.5mg/kg midazolam alone, Group H received 0.5 mg/kg hydroxyzine plus 0.5 mg/kg midazolam, and Group HM received 1mg/kg hydroxyzine plus 0.5 mg/kg midazolam. The observational part of the study was carried out prospectively during surgery. The Ramsay Sedation Scale (RSS), the heart rates (HR1: after induction of anesthesia; HR2: before retraction of orbital muscle; and HR3: right after retraction of orbital muscle), the muscles with OCR and the incidence of OCR (20% decrease of the HR right after the traction) were recorded and compared between the three groups. Results: The mean HR1, HR2 and HR3 values were significantly increased (p=0.002, p<0.001, p<,0.001) and the incidence of OCR (p=0.004) was significantly decreased in the Group H, and in the Group HM (for all, p<0.01) compared to the Group M. No statistically significant difference was found between the Group H and Group HM in terms of RSS, HR1, HR2, HR3 and the incidence of OCR (for all, p>0.05). The most common orbital muscle in which OCR occurred was the rectus medialis. Conclusion: Premedication with a combination of 0.5 or 1 mg hydroxyzine with 0.5 mg midazolam significantly reduced the incidence of OCR compared to the premedication with midazolam alone.