Plethysmography

Abstract

Plethysmography is one of the oldest and most useful methods of blood flow measurement. On line computation of blood flow during intensive care and anaesthesia and the non invasive measurement of cardiac output and peripheral blood flow are two major applications which are receiving attention at the present time. There are various types of plethysmograph, some of which can be accurately calibrated and some of which cannot, but all of which have found important application in central and peripheral blood flow studies. This paper is a review of the existing techniques and is designed to be useful in the selection of a particular technique for blood flow measurement.