ELECTRICAL AND MECHANICAL RESPONSES AFTER NEUROMUSCULAR BLOCKADE WITH VECURONIUM, AND SUBSEQUENT ANTAGONISM WITH NEOSTIGMINE OR EDROPHONIUM

Six unpremedicated patients who had given their informed consentwere given vecuronium 0.08 mg kg^–1 before elective surgery.Recovery from neuromuscular blockade was measured electricallyand mechanically. Neuromuscular blockade was antagonized 1 hafter the administration of vecuronium with two doses of neostigmine2.5 mg (three patients) or edrophonium 0.5 mg kg^–1 (threepatients). Although the onset of initial recovery was similar,subsequent recovery was faster when meassured electrically (EMG)than when measured mechanically. Recovery appeared to be fasterin younger patients. Reintroduction of neuromuscular blockadeoccurred after the second dose of neostigmine 2.5 mg, givento antagonize the block. This did not occur after either doseof edrophonium 0.5 mg kg^–1. ^*University College and Middlesex Hospitals, Mortimer Street,London W1 7PN.Department of Anesthesiology, U.C.L.A. Medical School, Los Angeles,U.S.A.