Rectal temperature (Tre) is often used to adjust measurements of blood gases, but these adjusted measurements may not approximate temperatures during intense exercise at main sites of gas exchange: muscle and lung. To evaluate differences in blood gases between sites, temperatures (T) were measured with thermocouples in the rectum (re), in mixed venous blood (v), in gluteal muscle (mu), and on ...

Methods for the determination of carbon monoxide in blood based on spectroscopic analysis (Hartridge, 1922; Klendshoj, Feldstein, and Sprague, 1950) are accurate only when relatively high concentrations of carbon monoxide are present. The two most accurate methods in current use are the manometric method of Van Slyke and Salvesen (1919) and the volumetric method of Scholander and Roughton (1943...

In humans, coronary blood flow is tightly regulated by microvessels within the myocardium to match myocardial energy demand. However, evidence regarding inherent sensitivity of the microvessels to changes in arterial partial pressure of carbon dioxide and oxygen is conflicting because of the accompanied changes in myocardial energy requirements. This study aimed to investigate the changes in co...

Ventilation-perfusion (VA/Q) inhomogeneity was modeled to measure its effect on gas exchange in the presence of inspired mixtures of two soluble gases using a two-compartment computer model. Theoretical studies involving a mixture of hypothetical gases with equal solubility in blood showed that the effect of increasing inhomogeneity of distributions of either ventilation or blood flow is to par...