Respiratory complications of rapidly progressive neuromuscular syndromes: Guillain-Barré syndrome and myasthenia gravis.

Neuromuscular respiratory failure is a common complication of both the Guillain-Barré syndrome and myasthenia gravis. Several key pathophysiological mechanisms contribute to the spiral of respiratory insufficiency in these diseases, including inspiratory, expiratory, and bulbar muscle weakness. It is important to identify patients with impending respiratory failure early to avoid emergency intubations. Several clinical features and bedside pulmonary function tests (PFTs) are useful in guiding decisions about intubation. Weaning is initiated when respiratory muscles have recovered sufficiently, and again, PFT criteria are helpful. Intravenous immunoglobulin and plasmapheresis are the cornerstones of specific therapy for both illnesses when complicated by respiratory failure. Mortality and morbidity are dramatically increased by respiratory failure and are mainly due to associated medical complications. Optimal outcomes depend on avoidance of these and prompt implementation of immunomodulatory therapy.