Are long-acting neuromuscular blockers contraindi-cated in middle ear surgery?
Although readily identifiable in a normal ear, the facial nerve may be difficult to locate in a diseased ear. External electrical stimulation of the facial nerve trunk and its muscular innervation may be required. Concurrent use of a long-acting neuromuscular blocker interferes with this test and is, therefore, contraindicated. Deep potent inhala-tion anesthesia is generally selected for middle ear surgery. Pre-existing facial nerve palsy eliminates such consid-erations and allows for the use of muscle relaxants. Debilitated patients may not tolerate the myocardial depressant effects of deep inhalational anesthesia, necessi-tating the employment of neuromuscular blockade. Under such circumstances, maintenance of 1 or 2 twitch responses to train-of-four stimulation should allow for facial muscle contraction during facial nerve stimulation. Before the use of neuromuscular blockers, the risks and benefits should be discussed with the surgeon and the patient.