Oculocardiac reflex in phacoemulsification: Peribulbar vs topical anesthesia.

Abstract

Purpose:This study compares the vital parameters and pain experienced during phacoemulsification under peribulbar and topical anesthesia to determine the incidence of OCR.Methods:One hundred six patients are enrolled for phacoemulsification in a prospective and randomized study. Fifty-two patients undergo surgery in a peribulbar block (Group PB) and 54 in topical anesthesia (Group TA). Mean arterial pressure (MAP) and pulse rate are recorded during a preoperative check-up and at four other steps of surgery. Pain experienced during surgery and on a postoperative day, 5, is graded with a verbal analogue scale. OCR defined as a decrease in pulse rate by greater than 20% is calculated. Chi-square test, Fisher‘s exact test, paired t test and the comparison of means give the statistical analysis. A value of P < 0.05 was taken as significant.Results:MAP readings at baseline versus MAP at other steps of surgery show a trend towards rising with a P value of < 0.05 in both groups. Pulse rate measured at all steps of surgery versus baseline pulse rate in Group TA shows P < 0.05. OCR is present in nine patients in peribulbar block verses eleven patients in topical anesthesia with P value of 0.687. The pain scores using verbal analogue scale were higher in Group TA compared with Group PB with a P < 0.0001.Conclusion:Oculocardiac reflex can occur during phacoemulsification under both peribulbar block and topical anesthesia, and the difference is not significant.