Effect of IV Midazolam Premedication on the Recovery of Pediatric Patients after Isoflurane Anesthesia for Cochlear Implant Surgery

Abstract

Midazolam, given by varying routes, is widely used as a premedication. This study was performed to investigate the effect of IV midazolam premedication on the recovery characteristics from isoflurane anesthesia in pediatric patients undergoing cochlear implant surgery. In this double-blind randomized study, a total of 60 unilateral cochlear implants procedures were performed on 60 children aged 1 – 6 years. They were 29 males (48.3%) and 31 females (51.7%). Patients were randomly allocated in one of two groups (M and S). Each group included 30 participants. Patients in group M received 0.01 mg/kg IV midazolam in 2 ml of 0.9% saline, while patients in group S received equal volume of 0.9% saline, two minutes before induction. Recovery times from discontinuation of isoflurane were recorded. Postoperative pain was assessed using Objective Pain Discomfort Score (OPDS). Emergence Agitation (EA) was recorded based on Aono’s four-point scale. There were statistically significant differences between patients pre-medicated with IV midazolam and those of the normal saline group as regards all measured recovery parameters (p<0.001). Patients in group M scored higher than those in Group S on the OPDS. Yet, this difference didn't show statistical significance (p=0.438) Among patients pre-medicated with midazolam, 17 (56.6%) suffered from EA compared to 12 (40%) patients from the other group. This difference did not reach statistical significance (p=0.196). Premedication with IV midazolam delayed recovery in pediatric patients undergoing moderately-long procedures when isoflurane was used as the inhalation anesthetic, while its effect on EA remains uncertain.