An evaluation of non-invasive blood pressure (NIBP) monitoring on the wrist: comparison with upper arm NIBP measurement.

The arm is the traditional site for application of an oscillometric non-invasive blood pressure (NIBP) cuff This study, which compares upper arm NIBP to wrist NIBP, involved 510 same arm sequential paired blood pressure (BP) measurements in 85 volunteers. Wrist NIBP consistently overestimated mean arterial, systolic and diastolic pressure by approximately 10 mmHg. Ninety per cent of the mean arterial pressure differences at the wrist were within a range of +/- 9 mmHg around a mean difference of 10.6 mmHg. The systolic pressure difference was 11.2 mmHg with 90% of differences between +/- 12 mmHg. The diastolic pressure difference was 10.2 mmHg with 90% of differences between +/- 9 mmHg. With the device used and within the normal blood pressure range, compensation can be performed by subtracting 10 mmHg from the measured values or simply by elevating the wrist about 15 cm and taking the BP at face value. Wrist NIBP may be a viable clinical alternative in situations where difficulty occurs with upper arm NIBP measurement.