TNO Finger Pressure Reference Guide - Integral Process

TNO Finger Pressure Reference Guide 24Pressure0 20 40 60 80 100 120 140 160 180 200Time (s)Figure 3.2 Example of a simultaneous tracing of brachial (black) and fingerarterial blood pressure (gray tracing, plotted with a pressure offset), (data fromstudy of Harms et al, published in Clin Sci 1999; 97; 291-301).3.2.1 Pulse wave distortionPressure pulsations are progressively distorted on their way towards the periphery.Finger blood pressure waveforms are more undulatory than brachial arterialpressure waveforms because of reflections of the systolic pulse wave in the arterialsystem of the arm. When finger pressure is compared to the intra-radial pressurethe distortion is less pronounced [SETTELS 1985].The next two figures (Figure 3.3 and Figure 3.4) provide two examples ofsimultaneous recordings of brachial and non-invasive finger arterial pressure in awoman aged 73 and a man aged 27. Note the small delay between the brachialpressure wave and the finger pressure wave due to time needed for the pulse waveto travel along the arm artery.