Association of Preoperative Midazolam Administration With Patient Anxiety During the Transition From the Preoperative Holding Bay to the Operating Room: A Prospective Observational Study.

Background Among patients awaiting surgical procedures, up to 80% experience anxiety. Midazolam is commonly administered in the preoperative holding bay to reduce anxiety. However, the effect of benzodiazepines can last longer than surgery and may lead to an increased risk of neurocognitive impairment. Thus, we looked into the effects of midazolam administration beyond the preoperative holding bay. We hypothesized that omitting midazolam in the holding bay increases anxiety in the operating room and the risk of unpleasant explicit recall. Methods This study included adult patients undergoing surgical procedures at Montefiore Medical Center (June-August 2024). Anxiety was assessed using the anxiety component of the Amsterdam Preoperative Anxiety and Information Scale, and midazolam was administered accordingly. We assessed postoperative unpleasant explicit recall in a follow-up survey. Mixed-effects linear and modified Poisson regression models were used for analyses. Results Among 765 patients studied, 27.5% received midazolam. The mean (standard deviation (SD)) anxiety level was 7.8 (4.3) in the holding bay and 7.9 (4.7) in the operating room. Compared to the non-midazolam group, those receiving midazolam experienced decreased anxiety from the preoperative holding bay to the operating room (adjusted mean difference (AMD): -2.0; 95% confidence interval (CI): -2.5 to -1.5; p<0.001). The association was stronger in female patients (AMD: -2.9; 95% CI: -3.5 to -2.3; p<0.001) versus male patients (AMD: -0.9; 95% CI: -1.6 to -0.1; p=0.029) and in younger (≤30) patients (AMD: -3.8; 95% CI: -5.1 to -2.6; p<0.001) versus older patients (AMD: -1.8; 95% CI: -2.4 to -1.3; p<0.001). In the follow-up cohort, midazolam demonstrated a trend towards reduced postoperative unpleasant explicit recall (adjusted risk ratio: 0.6; 95% CI: 0.4 to 1.1; p=0.103). The Richmond Agitation-Sedation Scale in the midazolam group (0 (0-0); median (interquartile range (IQR)) indicated effective anxiolysis without sedation. Conclusions In summary, our data show that anxiety levels increase from the preoperative holding bay to the operating room, an effect that was mitigated in patients who received a mean (SD) of 1.9 (0.6) mg of midazolam. This anxiolytic benefit was magnified in female and younger patients. These findings underscore the importance of continuous, structured anxiety assessments.