Comparison of remimazolam tosylate and propofol in patients undergoing general anesthesia using a laryngeal mask airway without muscle relaxants

It has been reported that anesthesia using propofol can frequently induce hypotension. Herein, we designed this study to compare the incidence of hypotension induced by propofol or remimazolam during laryngeal mask airway (LMA) anesthesia without muscle relaxants. 95 patients aged 18 to 65 years undergoing LMA anesthesia without muscle relaxants were randomly allocated to two groups. After 0.2 mu g/kg sufentanil, Group P received a bolus dose of 2 mg/kg propofol followed by a continuous propofol infusion, while Group R received a bolus dose of 0.3 mg/kg remimazolam followed by a continuous remimazolam infusion. The primary outcome was hypotension, defined as systolic blood pressure falling below 90 mmHg during anesthesia. Secondary outcomes included other adverse events. The success rate of initial LMA insertion, LMA insertion conditions, LMA removal time and changes in bispectral index (BIS) and hemodynamics during anesthesia induction, were also assessed. The results showed that the incidence of hypotension was not significantly different between the two groups (47.9% in group P and 36.2% in group R,p = 0.246). However, the BIS and heart rate during induction of anesthesia were significantly higher in group R than in group P (p < 0.05). Also, hiccups were more common in group R than in group P (14.9% vs. 2.1%, p = 0.031), and the LMA removal time was significantly longer in group R than in group P (12 min vs. 8 min, p = 0.001). We did not find a significantly lower incidence of hypotension in patients undergoing LMA anesthesia without muscle relaxants when comparing remimazolam to propofol, potentially related to the study's small sample size, and conducting a large-scale study using similar conditions could be inappropriate due to the risk of remimazolam-induced hiccups.