Evaluation of the anxiolytic effect of oral midazolam on pre-operative anxiety: Comparative study with diazepam and promethazine

ABSTRACT

The anxiolytic effect of oral midazolam [15 mg], diazepam [10 mg] and promethazine [50 mg], on preoperative anxiety was studied double blindly in three groups; each of 50 adult patients of both sexes, who had undergone moderate and major orthopaedic surgery. All the patients included in the study were selected with panic anxiety according to Taylor's scale [greater than 30] and psychogalvanic reflex wave amplitude [greater than 2.9 mv]. The study showed that three drugs did reduce the preoperative anxiety. Midazolam showed the most striking effect on reducing the degree of preoperative anxiety. This was evident by the significant reduction in the mean Taylor's score [20.5 +/- 1.9] and the mean psychogalvanic reflex wave amplitude [1.1 +/- 0.28 mv] 60 minutes after receiving the drug. This reduction was highly significant when compared with diazepam and promethazine. The three drugs showed significant reduction in the mean values of respiratory rate, pulse rate and systolic blood pressure. The decrease in respiratory rate was more with midazolam but was of no clinical importance. The decrease in blood pressure was marked with promethazine