In four patients with alveolar hypoventilation secondary to dysfunction of the respiratory
center, the clinical picture resembled, respectively, congenital heart disease, primary
polycythemia, arteriosclerotic heart disease and narcolepsy.
The diagnosis of primary alveolar hypoventilation should be suspected in a polycythemic
or cyanotic patient if central nervous system symptoms such as somnolence, headache
and easy fatigability are prominent, or if electrocardiographic and roentgenologic
evidence of right ventricular enlargement or strain are present in the absence of
dsypnea. The diagnosis can be established by demonstrating the arterial blood gas
changes to alveolar hypoventilation (elevated carbon dioxide, reduced oxygen saturation,
normal or low pH) in the absence of lung disease, extreme obesity or disease of the
neuromuscular apparatus of respiration.
It is suggested that the syndrome may occur as a complication of many neurologic diseases
because of the susceptibility of the medullary respiratory center to noxious agents.
Other manifestations of the underlying neurologic disease may be slight or absent,
and the clinical picture may be dominated by the sequelae of hypoventilation, anoxemia,
hypercapnia, polycythemia, right ventricular hypertrophy, strain and failure.
Our experience suggests that the primary hypoventilation syndrome is compatible with
prolonged life and that therapy should be directed primarily at maintaining normal
blood viscosity and cardiac compensation.