Measurement of Blood Flow and Volume in the Forearm of Man; With Notes on the Theory of Indicator-Dilution and on Production of Turbulence, Hemolysis, and Vasodilatation by Intra-Vascular Injection 1

Abstract

In the course of a series of studies on neuromuscular function it became desirable to investigate in man the metabolism of skeletal muscle in situ.For this purpose it was decided to apply the Zuntz-Fick principle to determine the exchange of metabolites between muscle and blood in the forearm with circulation occluded at the wrist.The selection of this segment was guided by the following considerations: (a) Convenience; (b) the large muscular volume relative to the volume of skin (1); (c) the predominance of blood flow through muscle relative to skin (2, 3); and (d) the relative avascularity of other structures suggesting that no less than 80 per cent of total forearm blood flow is muscular in distribution.In addition to the estimation of arterio-venous concentration differences in substances of interest, the principle requires a measurement of blood flow through the segment under study. Of methods in current use, only venous-occlusion plethysmography provides an absolute numerical value for blood flow through a human extremity. Despite the wealth of observations recorded by this method it was deemed desirable to develop another approach which might yield continuous recording of blood flow as well as serial samples of arterial and venous blood. Furthermore, the sources of error of the plethysmographic method have been studied carefully but not overcome completely (4), and, to our knowledge, no verification of the method by an independent technic has been made in man.

Mechanisms of postprandial protein accretion in human skeletal muscle. Insight from leucine and phenylalanine forearm kinetics.

“…This vein drained predominantly blood from muscle tissue (31). An additional catheter was placed into an antecubital vein of the opposite arm and used for isotope infusions.…”

Free fatty acid oxidation by forearm muscle at rest, and evidence for an intramuscular lipid pool in the human forearm.

“…Procedures for catheterization of the forearm and measurements of blood flow have been reported elsewhere (2,17). In brief, after local procaine infiltration, a deep and a superficial vein of the same arm were catheterized percutaneously in a retrograde direction.…”

“…All analytical measurements were corrected for the presence of heparin in the dead spaces of the precalibrated collection syringes (17). Forearm volume was measured by water displacement; 60% of this volume was assumed equivalent to the muscle mass (17).…”

“…All analytical measurements were corrected for the presence of heparin in the dead spaces of the precalibrated collection syringes (17). Forearm volume was measured by water displacement; 60% of this volume was assumed equivalent to the muscle mass (17). Blood or plasma flow was calculated by constant injection indicator dilution (17) and was expressed in milliliter per minute/ 100 g of muscle on the assumption that half the brachial arterial flow supplied forearm muscles.…”

The dispersion of indicator flowing through simplified models of the circulation and its relevance to velocity profile in blood vessels

“…But these are expected to arise solely as the result of differences in the length and cross-sectional area of the pathways. However, McDonald (1960, p. 57) states, on the basis of data obtained byAndres, Zierler, Anderson, Stainsby, Cader, Ghrayyib & Lilienthal (1954), that it is likely that extensive mixing occurs in peripheral arterial beds. But neither view appears to have been subjected to experimental verification and relatively little is known of the nature of blood flow in different parts of the circiulation.…”