[Ambulatory invasive and noninvasive blood pressure monitoring]

Indirect arterial blood pressure measurement has not changed substantially since its introduction by Riva-Rocci in 1986, Korotkoff in 1905 and Recklinghausen in 1906. Random measurements in the clinic or practice reflect only incompletely the dynamic nature of the blood pressure. Blood pressure recordings by patients themselves have provided more information through better temporal resolution, however, exact characterization of the pressure response throughout the entire day and, in particular, during physical exertion are not enabled; the latter are especially important with regard to diagnosis and treatment of hypertension. In 1966, therefore, radiotelemetric transmission of direct, continuously-measured arterial blood pressure was developed which enabled beat-to-beat registration of blood pressure, outside the laboratory, during normal daily life and sport activities. The initial results showed a marked variability of the blood pressure during the course of the day (Figure 1). Excessive blood pressure increases were observed during exposure to cold, static and dynamic exercise and to a lesser degree during automobile driving and exposure to heat (Figure 3). Recording of the pressure curves via transmission by radiotelemetry shows a high degree of accuracy and temporal resolution, spatial and situational freedom but is invasive and costly in terms of personnel. The same holds true for direct continuous blood pressure registration and storage on a portable tape recorder. Portable, automatic blood pressure measuring units for ambulatory monitoring employ indirect auscultatory or oscillometric recording with a cuff. As compared with the radiotelemetric direct continuous blood pressure measuring method, the indirect method has subordinate temporal resolution, that is, the measurements are only intermittent.(ABSTRACT TRUNCATED AT 250 WORDS)