Comparison of forearm plethysmographic methods with brachial artery pulsed Doppler flowmetry in man.

Blood flow in the forearm was evaluated using simultaneous measurements of pulsed Doppler flowmetry and strain-gauge plethysmography in 32 normal subjects and 91 patients with sustained essential hypertension. The two determinations of blood flow were strongly correlated (r = 0.58). Measurements with strain-gauge plethysmography reflected changes in blood flow velocity but were poorly correlated with changes in arterial diameter as measured by pulsed Doppler flowmetry. The latter method permits evaluation of instantaneous variations in blood flow velocity and detection of active modifications of arterial diameter.