[Development of direct and indirect ambulatory 24-hour blood pressure monitoring]

The direct ambulatory 24-hour blood-pressure monitoring has been applied in two ways. With the so called "Oxford-system", blood pressure is recorded via a cannula in the brachial artery which is connected to a perfusion unit that is worn around the neck, on the front of the chest, with a tape recorder carried in a pouch on the patient's belt. Using the micro-catheter blood-pressure telemetry recording is done in the same way, but transmission of the data to a stationary-receiving unit is managed by telemetry. The usage of the latter method is limited by the weight and complexity of the patient-sited equipment. Compared to the Oxford-system there is the advantage of continuously observing the patients blood-pressure "on-line" during the recording. The invasive character of both methods limits the application to special, scientific investigations. In recent years the indirect recording machines for 24-hour blood-pressure monitoring has been developed further. They are now accurate, easy to apply and simple to work out. Beside the auscultatory way of recording, with or without ECG-gating, the oscillometry recording machines have been improved. There should be automatically-operated intervals with recordings in day-time every 15-20 minutes and during the night every 30 minutes. The recorded data should be analysed by computer, calculating mean values with standard deviations in day-time and night-time separately. Further more, there should be a listing of reading-errors and probably corrected measurements.(ABSTRACT TRUNCATED AT 250 WORDS)