Monitoring the changes in peripheral vascular resistance using the shape of the radial blood pressure pulse

This study investigated the feasibility of monitoring changes in peripheral vascular resistance by analyzing the shape of the radial blood pressure (BP) waveform alone. The invasive radial BP waveforms from ten human volunteers were analyzed. Five subjects were given phenylephrine to increase peripheral resistance and propranolol to lower heart rate. The other five were administered nitroprusside to decrease peripheral resistance and glycopyrrolate to increase heart rate. With the vasoconstrictor, the BP waveshape showed a consistent increase in the amplitude of the late systolic peak and the diastolic wave. An opposite change was noted with the vasodilator. The authors describe a procedure for waveform analysis, which was successful in tracking beat-by-beat changes in peripheral vascular resistance