The impact of remimazolam on hypoxemia in elderly patients undergoing bronchoscopy: a prospective cohort study

Abstract

Background Fiberoptic bronchoscopy is a complex procedure that requires adequate anesthesia/sedation, and maintenance of safety is paramount. The elderly are at an increased risk of experiencing hypoxemia during flexible bronchoscopy. This prospective cohort study aimed to estimate whether remimazolam can reduce the incidence of hypoxemia during flexible bronchoscopy in elderly patients. Methods The elderly patients who underwent fiberoptic bronchoscopy were enrolled in this prospective cohort study. We evaluated the incidence of hypoxemia during bronchoscopy with remimazolam exposed vs propofol. Remimazolam group patients received remimazolam 0.15mg/kg i.v followed 1mg/kg/hr. infusion, and propofol group patients received propofol 1mg/kg i.v followed 4-6mg/kg/hr. infusion. The incidence rates of hypoxemia, severe hypoxemia, fully alert time, and adverse effects in both groups were compared. Results In the exposed group, a prevalence of 29.42% was observed compared to 60.00% in the non-exposed group (OR 2.10, 95% CI 1.18–3.74, P = 0.017) prior to controlling for potential confounding variables. Similarly, the overall incidence of severe hypoxemia was 24.64%, with a lower incidence in the exposed group compared to the non-exposed group (11.76% vs. 37.14%, OR 2.10, 95% CI 1.18–3.74, P = 0.017) before adjusting for confounding factors. No significant differences were found in hypotension, bradycardia, or hypopnea between the two groups. The incidence of hypotension was 17.65%, with a lower occurrence in the exposed group compared to the non-exposed group (17.65% vs. 37.14%, P = 0.0699), suggesting a trend towards clinical significance despite the small sample size. Modified Poisson regression found that remimazolam exposure was linked to a 57% lower risk of hypoxemia compared to propofol (RR 0.438, 95%CI 0.235–0.813, P = 0.009), and smoking was associated with a 64% lower risk of hypoxemia compared to non-smoking (RR 0.364, 95%CI 0.186–0.713, P = 0.003). Conclusion This observational cohort study highlights that using remimazolam sedative anesthesia can improve outcomes in elderly patients undergoing FB. Remimazolam is a safer option than propofol for FB in elderly. Trial registration: Clinicaltrails.gov: Retrospectively registered (ChiCTR2300071137; Registration date:05/05, 2023)