Respiratory Pattern and Respiratory Response to CO₂

Oxygen Chemoreceptors in Low Birth Weight Infants

“…Therefore, the present study has attempted to avoid many of the objections raised to previous studies of chemoreceptor activity in the neonate. The wide variation between individuals is not surprising, inasmuch as this is found in healthy adults as well [12].…”

Carbon Dioxide Tolerance: A Review

“…Hg. Schaefer and co-workers (43) reported an excellent large-scale respiratory study utilizing 65 subjects breathing various gas mixtures for periods of 15 minutes. At a Pu* of 11 mm.…”

Adaptation to Co2 With Particular Relation to Co2 Retention in Diving

“…The observed change in his ratio results in a 20-30 ft extension in the maximum safe depth after one year of duty. The changes in lung volumes, consisting of an increase in total lung capacity, vital capacity and tidal volume, and decrease in residual volume, might contribute to the reduced sensitivity to C0 2 because of the relationship found between large tidal volume, slow respiratory rate and low response to C0 2 (Schaefer, 1958).…”

“…Studies of acute exposure to various C0 2 concentrations on a large group of subjects established clearly the relationship of respiratory pattern and ventilatory response to C0 2 . Subjects with a large tidal volume and a low frequency showed a significantly lower response to C0 2 than those with a small tidal volume and high respiratory rate (Schaefer, 1958) (Kg. 1).…”

“…These results show a close parallelism to experiments after 3 per cent C0 2 exposure for three and six days, in which the same effect was observed (Haebisch, 1949;Schaefer, 1949). If the subjects are classified in a low and high ventilation group, according to the previously used procedure (Schaefer, 1958), it can be noted that the low ventilation group does tolerate the exposure to 1.5 per cent C0 2 without significant depression of the ventilatory response to 5 per cent C0 2 (Table 2). These subjects must be already partially adapted to a higher CO^ level before they are exposed to 1.5 per cent C0 2 and should show a respiratory pattern found to be associated with (1) the lowered response to C0 2 in acute conditions, and (2) respiratory acclimatization to C0 2 .…”