Changes in remimazolam plasma concentration associated with the Pringle maneuver during hepatectomy: a pilot study

Remimazolam (RMZ) is an ultrashort-acting benzodiazepine used in general anesthesia, metabolized rapidly by carboxylesterase 1, an enzyme primarily located in the liver. The Pringle maneuver (PM), an established technique commonly employed during hepatectomies to reduce bleeding, involves clamping major vessels, potentially affecting drug metabolism and clearance. Therefore, we conducted a study to investigate the changes in plasma concentration (Cp) of RMZ associated with the PM during hepatectomy and the impact on bispectral index (BIS) values.

This single-center prospective observational pilot study included ten patients undergoing hepatectomy using the PM.

Our findings showed that the changes in RMZ Cp immediately following each PM tended to be higher than those before PM in six cases, though this was not observed in others. However, there was no statistically significant difference between the median RMZ Cp after the final PM (1099 [723-1386] ng/mL) and before the initial PM (707 [641-856] ng/mL). Similarly, the median BIS value after the final PM (45 [40-46]) was comparable to the BIS prior to initiation of PM (46 [44-50]).

This study suggested that RMZ may be safely administered during hepatectomies with PM in patients with Child-Pugh classification A.

Clinical trial number: not applicable.