The present invention provides an apparatus and methods for continuous
intravascular measurement of whole blood concentration, blood pressure,
and pulse pressure. The intravascular catheter incorporates a sensor to
measure whole blood sound velocity, attenuation, backscatter amplitude,
and blood flow velocity and also incorporates existing technologies for
multiple physiologic measurements of whole blood. Pulse wave velocity and
wave intensity are derived mathematically for purposes of estimating
degree of local vascular tone.