The Lambert-Eaton myasthenic syndrome: a cause of delayed recovery from general anesthesia.

A 70-year-old man required prolonged ventilation after surgery to remove a rectal neoplasm. The cause of the slow recovery from the effects of neuromuscular blocking agents used during his anesthetic was the Lambert-Eaton myasthenic syndrome (LEMS). Before surgery, he had no neuromuscular symptoms, even in retrospect. LEMS should be considered in the diagnosis of prolonged recovery from neuromuscular blockade, even in previously asymptomatic patients.