Rigid spine syndrome and nocturnal alveolar hypoventilation.

A 17-year-old Japanese woman with rigid spine syndrome (RSS) presented with respiratory failure leading to CO2 narcosis. The clinical symptoms were drowsiness, asterixis and cardiac arrhythmias. Tracheostomy and temporary ventilatory support abolished these symptoms. However, polygraphic sleep studies without a ventilator revealed Cheyne-Stokes respiration and profound arterial oxygen desaturation during rapid eye movement sleep. Nocturnal ventilatory support improved not only nocturnal hypoxemia, but daytime blood gas values during spontaneous breathing. These findings indicate that the onset of respiratory failure is preceded by severe nocturnal hypoxemia and that the evaluation and control of nocturnal respiratory insufficiency is essential for RSS patients.