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 1993. 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 (V) over dot O-2) 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 (V) over dot E/(V) over dot CO2 were observed at the end-stage of exercise testing. Conclusions. These findings demonstrate that some patients with Ern develope bronchoconstriction during exercise.