Respiratory failure in Lambert-Eaton myasthenic syndrome.

Five patients with the Lambert-Eaton myasthenic syndrome who required more than 48 hours of mechanical ventilation for respiratory failure are described. All five had small cell bronchogenic carcinoma. In one patient with associated chronic bronchitis, one with interstitial pulmonary fibrosis, and one other, respiratory failure requiring mechanical ventilation developed as a result of the Lambert-Eaton myasthenic syndrome. The two other patients had received muscle relaxant drugs, but the acute respiratory failure episode in one of the two was not clearly related to their administration. One patient had an initial response to plasmapheresis, which allowed assisted mechanical ventilation to be discontinued. This improvement was not sustained, and the patient subsequently died in respiratory failure. Three patients survived to be dismissed from the hospital after they were weaned from mechanical ventilation.