小児トレッドミル運動負荷試験における呼気ガス収集用マスク装着の影響

Effect of a Face Mask for Gas Collection during Treadmill Exercise Testing in Children

　呼気ガス収集用マスク使用の運動負荷試験に及ぼす影響を検討した．17名の被験者において，第1回検査はマスクを装着せずに，次にマスクを装着して2回（第2,3回）トレッドミル運動負荷試験を実施した．各々の検査における運動持続時間，最高心拍数，最高酸素摂取量を検討した．第2回検査では第1回に比較して運動持続時間は有意に短縮した（856±241,724±246sec）．また，最高心拍数も有意に減少した（186±19,173±24 beat／min）．最高酸素摂取量は第3回検査で第2回に比較し有意に増加した（41±9,46±9ml／kg／min）．運動負荷試験に際し被験者の努力依存性指標を評価する時にはマスク使用の被験者に与える影響を考える必要がある．

We evaluated the influence of a face mask for gas collection during treadmill testing. Seventeen children underwent treadmill testing three times. The first examination was undergone without gas collection, and in the other examinations a collection mask was used. We evaluated each endurance time and peak heart rate. The values of peak oxygen uptake were compared in the second and the third examinations. Endurance time and peak heart rate decreased significantly more in the first examination than in the second examination (endurance time : 856±241 versus 724 ± 246 sec, peak heart rate : 186±19 versus 173 ± 24 beat/min, 0.05). Concerning peak oxygen uptake, the values were significantly higher in the third test than in the second. (peak oxygen uptake/kg : 41±9 versus 46±9 ml/kg/min, 0.05). The results of this investigation suggest that the subject's effort-dependent values such as endurance time, peak heart rate and peak oxygen uptake should be evaluated carefully, taking the effect of a face mask into consideration.