Intravenous Midazolam for Anxiolysis in MRI

Abstract

ObjectiveThe purpose of this project was to understand the effect of administration of intravenous (IV) midazolam on duration of procedure times and anxiety levels experienced by adult outpatients having magnetic resonance imaging (MRI). Secondarily, this project sought to compare duration of procedure times and anxiety scores of adult outpatients receiving intravenous lorazepam or intravenous diazepam for MRI-associated anxiety. MethodsAll adult outpatients scheduled for MRI over the course of 12 months were assessed for self-reported anxiety and offered anxiolytic administration. In this group, 116 adult outpatients received a benzodiazepine, 50 patients received midazolam, 35 received lorazepam, and 31 received diazepam. Patients rated their anxiety as zero (none), 1 (mild), 2 (moderate), or 3 (severe). Nurses rated the level of patient sedation using the Richmond Agitation Sedation Scale (RASS), a 10-point scale rating patients from combative (+4) to unarousable (−5). These scores were recorded upon arrival to MRI, following medication administration at the start of the MRI, and at the completion of the MRI. Duration of procedure times were measured as the time from anxiolytic administration to the time of MRI completion. ResultsUpon arrival to MRI, the average patient-reported anxiety levels for midazolam, lorazepam, and diazepam were 2.3 ± 0.6, 2.3 ± 0.7, and 2.3 ± 0.6; RASS scores were 0.8 ± 0.5, 0.7 ± 0.7, and 1 ± 0.7. Following benzodiazepine administration at the beginning of the MRI, the average patient-reported anxiety levels for midazolam, lorazepam, and diazepam were 1.4 ± 0.9, 1.5 ± 0.8, and 0.9 ± 0.6; RASS scores were −0.04 ± 0.7, 0.02 ± 0.8, and 0.1 ± 0.6. Patient-reported anxiety levels for midazolam, lorazepam, and diazepam following the MRI were 0.2 ± 0.6, 0.6 ± 0.7, and 0.03 ± 0.1; RASS scores were −0.1 ± 0.4, −0.2 ± 0.6, and −0.2 ± 0.4.Duration of procedure times for midazolam, lorazepam, and diazepam were 42.5 ± 28.9, 55.6 ± 19.8, and 49 ± 19 minutes. Vital signs decreased slightly after administration of all 3 drugs; however, not one adverse or over sedation event occurred. ConclusionIntravenous midazolam appears to be a safe and effective anxiolytic for adult outpatients in MRI. Patient anxiety scores and nursing assessed level of sedation scores were comparable to those taking IV lorazepam or IV diazepam. Duration of procedure times were also comparable to those receiving IV lorazepam or IV diazepam.