ABSTRACT
For routine clinical purposes, the mercury sphygmomanometer (Figure 22) remains a robust, reliable and accurate instrument for measurement of arterial pressure. Aneroid devices tend to be less reliable and should be checked at least once a year against a mercury instrument. Such a check is conveniently made using a ‘Y’ connection between the tubing of the two instruments. There is now a wide variety of electronic machines available for home blood pressure monitoring, although the standards of accuracy vary considerably. Equipment validated by robust protocols, such as outlined by the British Hypertension Society, is preferred.
