Wrist BP

Q: Blood Pressure (BP) taken at the wrist level is usually? - select one

A) falsely elevated

B) falsely lowered

Answer: A

Measuring non-invasive BP at the radial artery, i.e., wrist level, is not desirable, though it may be necessary in a few patients, such as those with axillary lymph node resection.

BP at wrist level is falsely elevated due to the hydrostatic pressure related to the lower position of the wrist relative to the heart. Additionally, the relatively small-diameter vessels in older adults are calcified and exhibit reduced elastance. Although BP can be measured with the wrist at heart level, wrist flexion may interfere with sensor positioning.

Wrist BP measurement requires equipment specifically designed for wrist BP, and devices used for brachial BP measurement should not be used.

#hemodynamics

References:

1. Muntner P, Shimbo D, Carey RM, et al. Measurement of Blood Pressure in Humans: A Scientific Statement From the American Heart Association. Hypertension 2019; 73:e35.

2. Palatini P, Asmar R, O'Brien E, et al. Recommendations for blood pressure measurement in large arms in research and clinical practice: position paper of the European society of hypertension working group on blood pressure monitoring and cardiovascular variability. J Hypertens 2020; 38:1244.

3. Zweiker R, Schumacher M, Fruhwald FM, Watzinger N, Klein W. Comparison of wrist blood pressure measurement with conventional sphygmomanometry at a cardiology outpatient clinic. J Hypertens. 2000 Aug;18(8):1013-8. doi: 10.1097/00004872-200018080-00004. PMID: 10953991.