Desflurane reduces the effective therapeutic infusion rate (ETI) of cisatracurium more than isoflurane, sevoflurane, or propofol

Abstract

Purpose: The present study investigated the interaction between the cumulative dose requirements of cisatracurium and anesthesia with isoflurane, sevoflurane, desflurane or propofol using closedloop feedback control. Methods: Fifty-six patients (18-85 yr, vitrectomies of more than one hour) were studied. In the volatile anesthetics groups, anesthesia was maintained by 1.3 MAC of isoflurane, sevoflurane or desflurane; in the propofol group, anesthesia was maintained by a continuous infusion of 6-8 mg·kg-1·hr-1 propofol. After bolus application of 0.1 mg·kg-1 cisatracurium, a T1%-level of 10% of control level (train-of-four stimulation every 20 sec) was maintained using closed-loop feedback controlled infusion of cisatracurium. The effective therapeutic infusion rate (ETI) was estimated from the asymptotic steady-state infusion rate 1ss. The 1ss was derived from fitting an asymptotic line to the measured cumulative dose requirement curve. The ETI of the different groups was compared using Kruskal-Wallis- test, followed by rank sum test, corrected for the number of comparisons, P <0.05 was regarded as showing significant difference. Results: ETI in the isoflurane group was 35.6 ± 8.6 μg·m-2·min-1, in the sevoflurane group 36.4- ± 11.9 μg m-2·min-1, in the desflurane group 23.8 ± 6.3 μg·m-2·min-1. The ETI of the volatile anesthetic groups were all significantly lower than the ETI in the propofol group at 61.7 ± 25.3 μg·m-2·min-1 (P <0.002). The ETI in the desflurane group was significantly lower than in all other groups (P <0.02). Conclusion: In comparison to propofol, isoflurane, sevoflurane and desflurane reduce the cumulative dose requirements of cisatracurium to maintain a 90% neuromuscular blockade by 42%, 41% and 60%, respectively.