Accession Number : AD0738832

Title :   Automated Constant Cuff Pressure System to Measure Average Systolic and Diastolic Blood Pressure in Man.

Descriptive Note : Technical rept.,

Corporate Author : HARVARD MEDICAL SCHOOL BOSTON MASS DEPT OF PSYCHIATRY

Personal Author(s) : Tursky,Bernard ; Shapiro,David ; Schwartz,Gary E.

Report Date : DEC 1971

Pagination or Media Count : 27

Abstract : An automated constant cuff-pressure system to remotely determine average human blood pressure levels was developed to overcome problems in measurement caused by natural beat-to-beat fluctuations in arterial pressure. A standard blood pressure cuff is inflated to approximately systolic pressure for a prescribed number of heart cycles. Korotkoff (K) sounds are picked up by a crystal microphone over the brachial artery. The ECG is recorded and an electronic coincidence circuit detects the number of R waves followed by a K sound. Cuff pressure is automatically adjusted until there is a 50% coincidence of R-K sounds. This cuff pressure is now by definition the median systolic pressure. The same procedure is followed to determine median diastolic pressure. A change is 2 mm Hg in cuff pressure alters the R-K coincidence by 25%, insuring an accuracy of measurement of plus or minus 2 mm Hg. Average measures of pressure obtained by the constant cuff pressure method were demonstrated to be as accurate as averages based on intra-arterial readings. Application of this system in epidemiological screening is discussed. (Author)

Descriptors :   (*BLOOD PRESSURE, *TELEMETER SYSTEMS), AUTOMATION, MEDICAL EQUIPMENT, EPIDEMIOLOGY, HYPERTENSION, HYPOTENSION, MEASUREMENT

Subject Categories : Biomedical Instrumentation and Bioengineering
      Telemetry

Distribution Statement : APPROVED FOR PUBLIC RELEASE