Mindray VS-900, Operator'S Manual

Page: 79 / 192

9-1
9
Monitoring NIBP
9.1 Overview
The monitor uses the oscillometric method for measuring the non-invasive blood
pressure (NIBP). This measurement can be used for adults, pediatrics and neonates.
Automatic non-invasive blood pressure monitoring uses the oscillometric method of
measurement. To understand how this method works, we’ll compare it to the auscultative
method.
With auscultation, the clinician listens to the blood pressure and determines the systolic
and diastolic pressures. The mean pressure can then be calculated with reference to these
pressures as long as the arterial pressure curve is normal.
Since the monitor cannot hear the blood pressure, it measures cuff pressure oscillation
amplitudes. Oscillations are caused by blood pressure pulses against the cuff. The
oscillation with the greatest amplitude is the mean pressure. This is the most accurate
parameter measured by the oscillometric method. Once the mean pressure is determined,
the systolic and diastolic pressures are calculated with reference to the mean.
Simply stated, auscultation measures systolic and diastolic pressures and the mean
pressure is calculated. The oscillometric method measures the mean pressure and
determines the systolic and diastolic pressures.
As specified by IEC80601-2-30 NIBP measurement can be performed during
electro-surgery and discharge of defibrillator.
NIBP diagnostic significance must be decided by the doctor who performs the
measurement.
NOTE

Blood pressure measurements determined with this device are equivalent to
those obtained by a trained observer using the cuff/stethoscope auscultatory
method or an intra-arterial blood pressure measurement device, within the
limits prescribed by the American National Standard, Manual, electronic, or
automated sphygmomanometers.