Methods for investigation of the forearm blood flow

Abstract

The limb circulation is widely used as a model for the study of hypertension and especially for estimation of the hemodynamic modifications induced by the administration of a drug. To understand the circulatory response of a limb, it is necessary to measure the fraction of flow exchanging substances with tissues (nutritive flow) as opposed to flow traversing shunt vessels which are capable of exchanging only heat. The metabolism to perfusion ratio and its distribution within the different tissues of the limb are also important parameters to be estimated. The ideal method must be non-invasive, accurate and reliable, it can be used at frequent intervals and not only at rest but also while the local circulation is varied, as widely as possible, by physical, chemical or nervous influence. Unfortunately, existing methods do not enable all of these measurements to be performed directly. However, considering together results obtained by various methods, most of this information can be obtained.