増田 敦子, 吉野 智佳子, 横井 麻理, 増山 茂
日本生理学会大会発表要旨集 2007 215-215 2007年
Because breath holding time (BHT) is influenced by a combined effect of alveolar PO2 and PCO2, it has been speculated that ventilatory responses to hypoxia and hypercapnia play an important roll to determine it. To clarify the contribution of respiratory chemosensitivities on breath holding (BH) performance, 15 healthy subjects were examined their BHT, the lowest SpO2, the lowest PETO2 and highest PETCO2 at breaking point (BP) of their BH trials with or without oxygen inhalation started from three different lung volumes, i.e., total lung capacity (TLC), functional residual capacity (FRC) and residual volume (RV). The data were compared with their isocapnic progressive hypoxic ventilatory response (HVR) and hypercapnic ventilatory response (HCVR). HVR showed significant negative correlation with PETO2 and SpO2 at BP as well as positive correlation with BHT.HCVR had not clear relationship with any parameters. We conclude that HCVR, but not HCVR, is a strong contributor to BH performance and that alveolar PO2 is a key determinant to BHT other than PCO2. [J Physiol Sci. 2007;57 Suppl:S215]