Analyses For Noninvasive Monitoring Of Arterial Blood Pressure By (I) Phono Cuff-Sphygmomanometry, For Discrete Measurements And (Ii) Arterial Ultrasonic Imaging, For Continuous Measurements

Analyses are developed for new procedures of (I) noninvasive discrete measurements of the brachial arterial blood pressure by phono cuff-sphygmomanometry (II) noninvasive continuous measurement of arterial blood pressure by arterial ultrasonic imaging. For the phono cuff-sphgmomanometry technique, analyses are developed for the vibration of the fluid-filled cuff-compressed arterial tube and for pressure pulse wave propagation through it, to derive an expression for the corrected brachial arterial pressure in terms of the monitorable auscultatory cuff pressure, the cuff width, the arm size and the principal frequency of the Korotkoff sounds. For the ultrasonic imaging technique, a large defor-mation analysis of the pressurized fluid-filled cylindrical nonlinearly elastic arterial tube is performed, to derive expressions for the arterial pressure and then for the pulse wave velocity (by invoking the distensibility definition) in terms of the arterial tube's nonlinear elasticity parameters (of the strain energy density function), and the unpressurized and deformed tube radii. Monitoring of the arterial radii and the associated pulse velocities at three dif-ferent instants yields, from the pulse wave velocity expression, adequate equations to determine the values of the unpressurized arterial tube radii and its elasticity parameters; they are substituted in the arterial pressure expression, to yield the arterial pressure continuously in terms of the continuously ultra-sonically monitorable arterial diameter.