Mathematical modelling of forearm circulation dynamics during Valsalva manoeuver based on non-invasive blood flow/pressure measurements

We present a mathematical model of forearm haemodynamics for assessing short term autonomic regulation of peripheral circulation. Non-invasive, continuous time measurements of omeral blood flow, viewed as the input to the model, and finger blood pressure, viewed as the output, are analyzed. The model has been used for beat-to-beat analysis of the dynamic blood flow/pressure relationship and has proven robust with respect to the large time-course changes in measured variables induced by the Valsalva manoeuvre. Our results showed a marked modulation of peripheral vasoconstriction in healthy subjects, which was less pronounced or even absent in patients with autonomic dysfunction. Our approach may thus become useful for assessing in clinical routine short term regulation of peripheral circulation in cardiovascular neuropathies.