Cardiopulmonary exercise testing in children - An individualized protocol for workload increase

Objectives: To investigate the feasibility of individualized workload incre ments, as used in adults, for exercise testing in children; and to investig ate whether this individualized protocol makes it possible to satisfy the u sual criteria for maximal exercise (clinical exhaustion, predicted maximum heart rate [HRmax], oxygen uptake [Vo(2)]plateau, maximal respiratory excha nge ratio > 1.1). Design: Prospective clinical study. Setting: Pediatric exercise testing laboratory. Subjects: Ninety-two children aged 3 to 17 years with various cardiac and r espiratory diseases (33 with asthma, 11 with bronchopulmonary dysplasia, 6 with cystic fibrosis, 10 with congenital heart disease, and 32 miscellaneou s). Interventions: Individualized maximal incremental exercise testing. The inc rease in workload was adapted to the individual and was calculated fr om pr edicted maximal oxygen uptake (iio,max) for each child. The test lasted 10 to 12 min. Results: The exercise test was well tolerated by all children and was maxim al in all but seven patients. A total of 65.7% of children reached the pred icted Vo(2)max and 68.1% satisfied the criteria for a Vo(2), plateau at pea k exercise. The predicted HRmax was achieved in all but two children. The m ean maximal respiratory exchange ratio was 1.06, Conclusion: The individualized protocol for increasing workload, based on V o(2), rather than power, was well tolerated by children. In our view, the b est two criteria for assessing the maximality of the tests were clinical ex haustion and HRmax, especially if the Vo(2), plateau was not reached. These results suggest that individualized protocols could be used instead of sta ndardized tests for exercise testing in children.