Replacing the mercury sphygmomanometer

When Scipione Riva-Rocci published his papers on a new sphygmomanometric technique in 18961 he could not have anticipated that his method was to become the mainstay of clinical measurement for over a century. Because of this long and fruitful record of service any threat to the familiar mercury sphygmomanometer is met with resistance—which may be interpreted as arising more from sentimentality than from scientific principle. But is this fair? May there not be more to the Riva-Rocci/Korotkoff technique than meets the eye? Clinical sphygmomanometry will change as we move into the next millennium. Firstly, we will no longer be allowed to use mercury, and with its passing will disappear the main argument against introducing the kilopascal as the unit of measurement—namely, that we measure what we see. Mercury will no longer be permitted because it is toxic to the environment, and the replacement of the millimetre of mercury with the kilopascal, used throughout science as the unit of pressure, may be seen as an opportunity to tidy up an irksome anomaly in scientific nomenclature.2 3 The mercury …