The role of hyperventilation in exercise-induced bronchoconstriction.

Significant bronchoconstriction, comparable in severity to that observed after moderate treadmill exercise, was induced in asthmatic children by voluntary isocapnic hyperventilation of 3-min and 10-min duration. In both hyperventilation and exercise, nasal breathing inhibited the bronchoconstrictive responses, whereas mouth breathing potentiated the bronchoconstrictive response. In the asthmatic children, 10 min of voluntary isocapnic hyperventilation did not represent a greater bronchoconstrictive stimulus than did 10 min of exercise or 3 min of isocapnic hyperventilation.

The beneficial effect of nasal breathing on exercise-induced bronchoconstriction.

In the first step of a study of the relation of nasal and oral breathing during moderate treadmill exercise to the onset of bronchoconstriction in young patients with perennial bronchial asthma, it was observed that most subjects spontaneously breathed with their mouths open when instructed to breathe "naturally." Subsequently, when they were required to breathe only through the nose during the exercise, an almost complete inhibition of the postexercise bronchoconstrictive airway response was demonstrated. When instructed to breathe only through the mouth during exercise, an increased bronchoconstrictive airway response occurred, as measured by spirometry, flow-volume relationships, and body plethysmography.

Hydrops fetalis, hydramnios and hepatic vascular malformation associated with cutaneous hemangioma and chorioangioma.

A premature baby presented with severe hydrops fetalis due to a multifocal angiomatous malformation of the liver. There were two other small vascular tumors: hemangioma of the skin and chorioangioma. Hydramnios and placental edema were also present.