The Effect of the Inhalation of High and Low Oxygen Concentrations on Respiration, Pulse Rate, Ballistocardiogram and Arterial Oxygen Saturation (Oximeter) of Normal Individuals

Respiratory Regulation During Exercise in Unconditioned Subjects 1

“…This is because the results of these investigators show an immediate return of ventilation to the same steady rate as before when the subject is switched back to air. It seems a little simpler to assume that the chemoreceptor system becomes more sensitive to the arterial oxygen tension itself, or that the respiratory center becomes more sensitive to the "tone" which is known to exist at normal oxygen tensions in the resting state (40). In the latter case, the oxygen effect could be regarded as a variety of neurogenic stimulus which becomes more active the more severe the exercise.…”

“…The effect on ventilation of inhaling high and low oxygen concentrations at rest has been studied by Dripps and Comroe (40). They found a small, immediate drop of 3.1%o in ventilation on passing from air to oxygen.…”

Effects of Oxygen Breathing on the Heart Rate, Blood Pressure, and Cardiac Index of Normal Men—resting, With Reactive Hyperemia, and After Atropine*

“…The effect of hyperoxia on heart rate of normal subjects is progressive with increasing concentrations of inspired oxygen from 15 to 100 per cent. 5. A far higher range of chemoreceptor activity is suggested than has previously been generally recognized.…”

“…This change is probably related to the slight hyperventilation that occurs when normal subjects breathe 100 per cent oxygen (5). No large change in Pco2 was observed, and the mean arterial oxygen saturation during air breathing was 95 per cent (Table VI).…”

“…At least three independent groups reported decreases in cardiac output in normal subjects breathing oxygen as estimated by ballistocardiograph-decreases averaging 8 to 10 per cent and largely due to decreased heart rate (5,8,20 (21).…”