Effect of intramuscular midazolam premedication on patient satisfaction in women undergoing general anaesthesia: a randomised control trial

Abstract

Objective: To determine the effect of premedication with intramuscular midazolam on patient satisfaction in women undergoing general anaesthesia.

Trial design, setting and participants: Double-blind, parallel randomised control trial at a tertiary care medical centre in South Korea. Initially, 140 women aged 20-65 years who underwent general anaesthesia and had an American Society of Anesthesiology physical status classification of I or II were randomly assigned to the intervention group or the control group, and 134 patients (intervention n=65; control n=69) completed the study.

Intervention: Intramuscular administration of midazolam (0.05 mg/kg) or placebo (normal saline 0.01 mL/kg) on arrival at the preoperative holding area.

Main outcomes: The primary outcome was the patient's overall satisfaction with the anaesthesia experience as determined by questionnaire responses on the day after surgery. Satisfaction was defined as a response of 3 or 4 on a five-point scale (0-4). The secondary outcomes included blood pressure, heart rate, oxygen desaturation, recovery duration and postoperative pain.

Results: Patients who received midazolam were more satisfied than those who received placebo (percentage difference: 21.0%, OR 3.56, 95% CI 1.46 to 8.70). A subgroup analysis revealed that this difference was greater in patients with anxiety, defined as those whose Amsterdam Preoperative Anxiety and Information Scale anxiety score was ≥11, than that for the whole sample population (percentage difference: 24.0%, OR 4.33, 95% CI 1.25 to 14.96). Both groups had similar heart rates, blood pressure and oxygen desaturation.

Conclusion: Intramuscular administration of midazolam in women before general anaesthesia in the preoperative holding area improved self-reported satisfaction with the anaesthesia experience, with an acceptable safety profile.

Trial registration number: KCT0006002.

Keywords: adult anaesthesia; anaesthetics; quality in health care.

Figure 1

Study flow diagram.

Figure 2

Overall satisfaction with the anaesthesia experience for (A) all patients and (B) anxious patients with APAIS score for anxiety ≥11. APAIS, Amsterdam Preoperative Anxiety and Information Scale.

Figure 3

Patient responses regarding (A) satisfaction with premedication, (B) satisfaction with anaesthesia in the operating room, (C) satisfaction with postoperative pain control and (D) willingness to receive the same anaesthesia if needed.