Mercury Versus Automated Blood Pressure Monitoring

Despite the clear guidelines on manual blood pressure technique, there seems to be large inter-observer variations, both among nursing staff and physicians. These differences are further complicated by variables such as cuff selection and application, incorrect cuff positioning and rapid cuff deflation rate, inadequate rest period, and lack of repeated measurements. The blood pressure measurement obtained by an automated device is not as dependent on observer training and competency as the manual mercury device, yet its use requires careful patient evaluation for caffeine or nicotine use, cuff position, and proper wrist positioning, and instructing the individual not to move or talk if accurate blood pressures are to be obtained. If one performs the automated readings and manual blood pressure measurements under standardized conditions, the mean values will be quite similar; however, this possibility has not yet been fully tested.

Therefore, there is a need to assess systematically if there is in fact a difference in the two blood pressure monitoring approaches under controlled conditions. The goal of this study, then, is to examine our current practice of obtaining manual blood pressure measurement using a mercury sphygmomanometer compared to an automated wrist-mounted blood pressure device.

A possible implication of this study is if the blood pressure measurements using the automated blood pressure device are comparable to the measurements obtained using the mercury sphygmomanometer, than the mercury devices can be replaced by the more environmentally acceptable automated devices in our clinical research setting.