Abstract

Myasthenia gravis is an autoimmune disease that results from antibodies against post-synaptic nicotinic acetylcholine (Ach) receptors at the neuromuscular junction (NMJ). Myasthenia gravis (MG) is a long-term disease that leads to varying degrees of skeletal muscle weakness. Ocular, facial, and pharyngeal muscles are most commonly affected. Those affected often have thymic hyperplasia or develop a thymoma. Diagnosis is by blood tests for specific antibodies, edrophonium test or nerve conduction studies. Acetylcholinesterase inhibitors are the first line drugs of treatment. Sometimes immunosuppressants like prednisone or azathioprine may also be used. Plasmapheresis and high-dose intravenous immunoglobulin may be used during MG crisis. Thymectomy may induce remission or reduce the antibodies against Ach receptors. If the respiratory muscles are involved significantly, mechanical ventilation may be required. Anesthesia for myasthenia gravis is challenging for anesthesiologists because of the interaction of anticholinesterase drugs with both depolarizing and non-depolarizing muscle relaxants. Several reports have been published on anesthetic management of myasthenic patients undergoing transsternal thymectomy.

Key words: Acetylcholinesterase inhibitors, Autoimmune disease, Myasthenia gravis, Thymectomy