Blood Pressure Sensor Theory of Operation
The PS-2207 Blood Pressure Sensor uses an oscillometric method to calculate the systolic and diastolic blood pressure of a subject. This is the most common method for automated blood pressure measurements because the method is non-invasive and simpler to automate than the traditional ascultatory method, which typically requires a carefully trained practitioner to give accurate results.
Both the asculatory and oscillometric methods of blood pressure measurement are accepted by the American Association of Critical Care Nurses; however, the oscillometric method may give slightly different results between different measurement systems of blood pressure sensors due to differences in the algorithms used to determine the systolic and diastolic pressures from the oscillometric envelope.
Theory of Operation
Maximum oscillation in the pressure of a cuff will occur at the mean arterial pressure PMA of the subject because there is maximum mechanical coupling between the cuff pressure and the arterial pressure at that point. Systolic pressure is the maximum arterial pressure during contraction of the left ventricle of the heart. The systolic and diastolic reading could be read directly from the maximum fluctuation in the cuff pressure; however, in practice the maximum oscillation from a heart seldom occurs exactly at the pressure at which the pressure in the cuff exactly matches the mean arterial pressure. Furthermore, the point at which the oscillations first begin to appear can be difficult to discriminate from the noise level; therefore, the systolic and diastolic pressures are in practice always calculated from the oscillometric envelope using algorithms that are designed to match the systolic and diastolic measurements obtained using the traditional ascultatory method:
Please see the American Association of Critical Care Nurses for more information on accepted measurement technique.
Creation Date: 11/16/2010