PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 13790336

Pulmonary capillary blood volume, flow and diffusing capacity during exercise.

R L JOHNSON·W S SPICER·J M BISHOP·R E FORSTER
View original source ↗Export metadata ↓

Abstract

The source did not provide an abstract. Follow the original record for more information.

Explore related subjects

Blood VolumeCapillariesCell RespirationExerciseHumansLungPhysical ExertionRespirationEXERTION/physiologyLUNG/blood supplyRESPIRATION/physiologyJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

R L JOHNSON, W S SPICER, J M BISHOP, R E FORSTER. 1960. Pulmonary capillary blood volume, flow and diffusing capacity during exercise.. https://doi.org/10.1152/jappl.1960.15.5.893

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2005

Small volume hypertonic resuscitation of circulatory shock.

Small volume hypertonic resuscitation is a relatively new conceptual approach to shock therapy. It was originally based on the idea that a relatively large blood volume expansion could be obtained by administering a relatively small volume of fluid, taking advantage of osmosis. It was soon realized that the physiological vasodilator property of hypertonicity was a useful byproduct of small volume resuscitation in that it induced reperfusion of previously ischemic territories, even though such an effect encroached upon the malefic effects of the ischemia-reperfusion process. Subsequent research disclosed a number of previously unsuspected properties of hypertonic resuscitation, amongst them the correction of endothelial and red cell edema with significant consequences in terms of capillary blood flow. A whole set of actions of hypertonicity upon the immune system are being gradually uncovered, but the full implication of these observations with regard to the clinical scenario are still under study. Small volume resuscitation for shock is in current clinical use in some parts of the world, in spite of objections raised concerning its safety under conditions of uncontrolled bleeding. These objections stem mainly from experimental studies, but there are few signs that they may be of real clinical significance. This review attempts to cover the earlier and the more recent developments in this field.

Blood Volume↗
PubMed2005

Theory of susceptibility-induced transverse relaxation in the capillary network in the diffusion narrowing regime.

The transverse relaxation effect of deoxyhemoglobin compartmentalization in erythrocytes in the capillary network is investigated using an analytical approach. The capillaries are modeled as long arrays of paramagnetic spheres, simulating the individual red blood cells. Calculations are performed in the diffusion narrowing regime, which holds for the native blood paramagnetism at moderate fields up to about 1.5 T, for the free induction decay, the Hahn spin-echo, and the Carr-Purcell-Meiboom-Gill sequence. The commonly used model of capillaries as homogeneously magnetized cylinders is shown to underestimate the capillary contribution to the susceptibility-induced relaxation rate by up to 55%. This results in a noticeable change in the predicted deoxyhemoglobin concentration needed to cause the variation in the transverse relaxation rate observed in functional MRI and may affect subsequent quantification of physiological parameters derived from the BOLD signal. Furthermore, the model for the individual red blood cells (RBCs) represents a framework for investigating the effects of interspecies and intersubject variations in hematocrit, RBC deoxyhemoglobin concentration, and cell size on the relaxation rate. The results agree within their validity domain with previous Monte Carlo simulations.

Blood Volume↗