EDROPHONIUM AND HUMAN PLASMA CHOLINESTERASE COMBINATION FOR ANTAGONISM OF MIVACURIUM-INDUCED NEUROMUSCULAR BLOCK

We have compared the reversal characteristics of mivacurium after admi nistration of an edrophonium-plasma cholinesterase (PCHE) combination with that produced by each antagonist alone. Forty ASA I adults were g iven mivacurium 0.15 mg kg(-1) during fentanyl-thiopentone-nitrous oxi de-isoflurane anaesthesia. TOF stimulation was applied to the ulnar ne rve every 12 s, and the force of contraction of the adductor pollicis muscle was recorded. When spontaneous recovery of first twitch height (T1) reached 10% of its initial control value, patients were allocated randomly to one of four groups (n = 10 in each). Neuromuscular functi on in patients in group 1 (control group) was allowed to recover spont aneously. Patients in groups 2-4, respectively, received edrophonium 1 mg kg(-1) (group ED), exogenous PCHE equivalent to activity present i n 25 ml kg(-1) of human plasma (group PCHE) or edrophonium 1 mg kg(-1) with exogenous human PCHE equivalent to the activity present in 25 mi kg(-1) of human plasma (combination group). The time to attain a TOF ratio of 0.75 in the combination group was 4.6 (so 0.9) min. This was shorter (P<0.01) than that observed in patients in the control (16.8 ( 3.3) min), ED (8.9 (3.6) min) and PCHE (9.3 (1.6) min) groups. There w as no difference in recovery indices between groups ED and PCHE. We ha ve demonstrated that the edrophonium-PCHE combination significantly ac celerated recovery of mivacurium-induced block compared with that obse rved with the use of individual antagonists.