Respiratory Responses to Intravenous and Intrapulmonary CO2 in Awake Dogs
Document Type
Article
Publication Date
7-1978
Department
Engineering & Computing Sciences
Abstract
Ventilatory responses to CO2 inhalation and CO2 infusion were compared in the awake dog. The CO2 was introduced directly into the systemic venous blood via a membrane gas exchanger in a femoral arteriovenous shunt circuit, and the extracorporeal blood flow, QX, was maintained constant at one of two rates: low, 0.5 l/min; or high, 2.0 l/min. A total of 13 experiments was performed in four dogs comprising 50 control and 25 inhalation and infusion observations at each of the two flow rates. Comparison of CO2-response curve slopes, S = delta V E/delta PaCO2, between CO2 inhalation and infusion showed no significant difference either within or between flow rates. The mean value of S for all conditions was 1.88 l/min per Torr with a 95% confidence interval of 1.66 -2.14. An independent additive ventilatory drive amounting to 28% of low-flow control VE was found at the highflow rate. We conclude that at constant blood flow the responses to both CO2 inhalation and infusion are hypercapnic and not significantly different.
DOI
https://doi.org/10.1152/jappl.1978.45.1.109
First Page
109
Last Page
114
Publication Title
Journal of Applied Physiology
Recommended Citation
Greco, E. C., Fordyce, W. E., Gonzalez, F., Reischl, P., & Grodins, F.S. (1978). Respiratory responses to intravenous and intrapulmonary CO2 in awake dogs. Journal of Applied Physiology, 45(1):109-114. https://doi.org/10.1152/jappl.1978.45.1.109