Effects of Hyperpnea on Values of Electric Flicker

By means of Motokawa's method of electric flicker (EF), we measured variations of electric flicker values (EFV) of 5 subjects caused by hyperpnea, the inhaled gases being air, 100% O2 and 1% CO2 in 2. Measurements by an ear oximeter were carried out in parallel. 1. During 5 minutes' deep breathing of air, both EFV and oximeter values (Oxi-V) increased. 2. Also by deep breathing of pure oxygen, both kinds of values increased. 3. In case of 100% O2 inhalation (normal breathing), Oxi-V increased, but no change occurred in EFV. 4. In case of hyperpnea of 1% CO2 in O2, Oxi-V increased, while no change could be found in EFV. From these findings it was concluded that the change in EFV by hyperpnea is due to acapnia.