Control unit for deriving a measure of arterial compliance

A controller for deriving a measure of arterial compliance, operably couplable in use with an oscillometric blood pressure measurement device,

• the controller adapted to:
• receive, from the oscillometric blood pressure measurement device, an arterial volume signal indicative of a variation in arterial volume of an artery assumed to be in contact with the measurement device, as a pressure applied to the artery by the measurement device is varied across a range of pressures;
• extract from said arterial volume signal a peak-to-peak volume amplitude signal indicative of a peak-to-peak amplitude of the arterial volume across said range of applied pressures;
• receive a signal indicative of a variation in pulse arrival time at a particular location along said artery as said applied pressure is varied across said range of pressures;
• derive from said extracted peak-to-peak volume amplitude signal, a signal, Va-osc, indicative of arterial volume as a function of arterial transmural pressure, based on a first model fitting procedure employing a pre-determined arterial volume model;
• and
• derive an output measure indicative of arterial compliance based on the derived Va-osc signal and based on the acquired signal indicative of variation in pulse arrival time, using a further model fitting procedure employing a pre-determined pulse arrival time model relating variation in pulse arrival time, arterial volume, and arterial compliance.