Atracurium after an anticholinesterase: Does prior reversal with edrophonium or neostigmine influence the response to atracurium?

This study documents the response to atracurium (75 μg.kg−1) administered 30 min after a pancuronium‐ or tubocurarine‐ induced neuromuscular block has been reversed with either neostigmine (50 μg.kg−1) or edrophonium (0.5 μg.kg−1). Twenty‐one ASA 1 or 2 patients were studied, of whom H received neostigmine and 10 edrophonium. The degree of neuromuscular block was measured electromyographically from the first dorsal interosseous muscle of the hand using train‐of‐four stimulation of the ulnar nerve. When atracrium was administered, the single twitch response compared with control was 100% in all patients and the mean train‐of‐four ratios were 91% and 65% in the neostigmine and edrophonium groups respectively. After atracurium (75 μg.kg−1), minimum values for the single twitch response compared with control were 52% and 66% in the neostigmine and edrophonium groups respectively. Prior administration of atracurium appears to potentiate the neuromuscular blocking effects of atracurium administered 30 min later. Copyright © 1993, Wiley Blackwell. All rights reserved