Cuff Pressure Pulse Waveforms: Their Current and Prospective Applications in Biomedical Instrumentation

Abstract

Use of the arterial pulse in the evaluation of disease states has a long history. Examination of the arterial pulse is recorded by historians as being an essential part of ancient Chinese, Indian, and Greek medicine. Palpation of the pulse was very much a part of the “art” of medicine with a bewildering array of terminologies. The first accurate recording of the arterial pulse in man was performed by Etienne Jules Marey in the nineteenth century. Marey (Marey, 1881) developed a series of mechanical devices used to noninvasively record the radial pulse in humans for physiological and clinical studies. His device for the recording the peripheral arterial pulse, the sphygmogram, was soon taken up by leading clinicians of the day, who considered the contours of the arterial pulse waveform to be important for diagnosing clinical hypertension. Interest developed in detecting the onset of hypertension in asymptomatic individuals. The principal means of doing this in the late nineteenth century was using a variety of types of sphygmographs to record the arterial pulse in a wide range of asymptomatic individuals. For the first time in history, the range of contours of the human arterial pulse was recorded and interpreted. In 1886, Marey placed the forearm and hand in a water-filled chamber to which a variable counter-pressure was applied. The counter-pressure for maximum pulse wave amplitude detected in the chamber determined that the vessel walls were maximally relieved of tension at that counter-pressure. When counter pressure was increased or decreased, the amplitudes of pulsations in the chamber decreased. This process was called vascular unloading. In the early twentieth century the Italian physician Riva-Rocci invented the cuff sphygmograph (Riva-Rocci, 1896). Riva-Rocci used palpation to determine the systolic pressure. The cuff sphygmograph was later improved by the use of Korotkoff sounds that were discovered by Korotkov (Korotkov, 1956). The use of Korotkoff sounds made the sphygmomanometer much simpler to use and allowed the clinician to base diagnosis and treatment on just two numbers, the systolic and diastolic pressures, rather than requiring the rigors of arterial waveform interpretation. The cuff sphygmomanometer was rapidly introduced into clinical practice and replaced the sphygmogram as part of the evaluation of