Eucapnic voluntary hyperventilation test in children.

BACKGROUND: In children, exercise-induced dyspnea is a common symptom that can be due to dysfunctional breathing. EVH test has bee used especially in elite athletes as bronchoprovocation test. Currently, there are only few studies on the EVH test. New research methods are required alongside the traditionally used tests especially due to dysfunctional breathing disorder.

PURPOSE: The purpose of the "pilot study" was to study the usability of the EVH test with real time biofeedback in children of 10-16 years of age in the diagnostics of exercise-induced dyspnea.

METHODS: Six 10-16-year-old teenagers with history of exercise-induced dyspnea and three healthy control subjects were selected for the study. A 6-minute EVH test with realtime biofeedback was performed on the patients and the diagnosis was confirmed on the basis of clinical findings and spirometry follow-up either as normal, asthma or dysfunctional breathing.

RESULTS: The study was successful in the patients. In the spirometry follow-up, three patients had bronchoconstriction (FEV1 decline over 10%), dysfunctional breathing condition was observed in three patients and three control patients experienced no symptoms. Only two DFB-patients didn't reach the target level of minute ventilation due to a clinical symptom (inspiratory stridor).

CONCLUSION: The EVH test was successful in the 10-16-year-old children having participated in the study and the test was well tolerated. Through the study, it was possible to provoke both dysfunctional breathing disorder and bronchoconstriction in the symptomatic patients. Based on the pilot study, EVH test seems to be usable in the diagnostics of pediatric exercise-induced dyspnea but larger studies are warranted to confirm our preliminary findings.