Cardiorespiratory response to exercise in patients with exercise-induced bronchial obstruction.

OBJECTIVE

To document the characteristics of the ventilatory response to exercise in patients with exercise-induced bronchial obstruction (EIB).

EXPERIMENTAL DESIGN

Comparative study during the period between December 1993 and March 1994.

SETTING

Ambulatory care in Ohgaki Municipal Hospital.

SUBJECTS AND METHOD

We evaluated 11 children with EIB. Each subject under went symptom-limited cardiopulmonary treadmill exercise testing (Bruce protocol).

RESULTS

Patients with EIB showed a significantly lower peak oxygen consumption (peak VO2) than the control subjects. Three patients with EIB developed relative hypoventilation during incremental exercise: an increase in end-tidal carbon dioxide partial pressure (PETCO2) and a decrease in VE/VCO2 were observed at the end-stage of exercise testing.

CONCLUSIONS

These findings demonstrate that some patients with EIB develop bronchoconstriction during exercise.