Techniques for the evaluation of microvascular and venous functions in man: an overview

The pharmacodynamic evaluation of venotropic compounds deals mainly with va scular reactivity and fluid exchanges. At the microvascular level, three ki nds of approaches can be used: (1) clinimetric measurements of cutaneous te mperature (thermometry), skin colour (chromametry) and leg volume; (2) indi rect physical parameters evaluating the haemodynamic or nutritional efficac y of the microcirculation (TcPO2 and laser doppler); (3) capillaroscopy wit h digital image analysis, which allows a quantification of the microvascula r bed, of some kinds of transcapillary exchanges and of lymphatic microcirc ulation. At the venous level, they are also several usable techniques: (1) US duplex, which allows measurements of venous diameter variations; (2) ple thysmography, which evaluates the compliance of the venous system from pres sure/volume curves.