Standard algorithm of blood-pressure measurement by the oscillometric method

An automated system for the functional evaluation of oscillometric non-invasive blood pressure monitors

Most of the automated non-invasive blood pressure (NIBP) monitors in clinical use rely on the oscillometric technique for measuring the blood pressures. The functional evaluation of these monitors has relied on comparison with intra-arterial blood pressure measurements or comparison with 'standard' non-invasive blood pressure meters such as the Hawksley random zero sphygmomanometer. The commercial availability of simulated arm test instruments provides the opportunity for developing an alternative evaluation method. We describe the control of an NIBP simulator by a personal computer which is also linked to the NIBP monitor under test. An evaluation protocol is described and the data analysed to present graphically and in tabular form an assessment of the NIBP monitor.

Comparison of oscillometric and intra-arterial blood pressure and pulse measurement

Non-invasive oscillometric blood pressure and pulse measured by an Omron HEM-703CP monitor were compared with arterial values obtained from direct measurements of the radial artery. An excellent correlation and agreement was found between the two methods (systolic r = 0.99; diastolic r = 0.97; pulse r = 0.99), although there was some variability among individual subjects. The range of difference between them was 0 to 10 mmHg for systolic and -6 to +5 mmHg for diastolic pressures. When tested on the bench using the Metron QA-1280 non-invasive blood pressure analyser the HEM-703CP monitor rarely exhibited errors exceeding 2-3 mmHg over a measurement range of 50-200 mmHg.