The effect of pulsatile blood flow on blood pressure regulatory mechanisms

This paper demonstrates that the effect of pulsatile blood flow on the baroreflex is to effectively reduce the gain of the baroreflex loop. This has important implications for both the development of integrative physiology models, which do not include pulsatile blood flow, and the use of non-pulsatile ventricular assist devices with either replace the heart or assist the heart in achieving adequate blood circulation. To elucidate the effect of the pulsatile nature of blood flow, we utilise the concept of an equivalent nonlinearity to replace the baroreflex curve, driven by a pulsatile blood flow/pressure signal, with an equivalent nonlinearity corresponding to a non-pulsatile situation. Tests are performed on a feedback model for the peripheral resistance baroreflex and conclusions made to the stability implications, using a describing function analysis.