Appropriate sphygmomanometer should be selected

EDITOR—Users of mercury sphygmomanometers are being advised to consider alternatives, but this is causing problems. 1 2 Currently there is confusion over the advantages and disadvantages of the alternatives. The mercury sphygmomanometer, when used by trained staff, is the gold standard. Aneroid devices are also in widespread use, but they can be knocked out of calibration easily. These devices can be used, provided they are recalibrated every six months, but indications are that this advice is rarely taken.

Automated devices are now readily available. The British Hypertension Society states that for these devices to be acceptable, no more than 25% of measurements should be in error by more than 10 mm Hg and no more than 10% by 15 mm Hg.3 Automated devices have …