Measurement of Blood-pressure: Comparison of Intra-arterial and Cuff Values

Abstract

In recent years numerous reports have appeared-for example, Pickering (1955)-of discrepancies between arterial bloodpressure measured by an intra-arterial method and by the usual cuff and sphygmomanometer. Part of this discrepancy has been attributed to the effect of arm circumference on arterial pressure measured with a cuff. Corrections based on measurements made by Ragan and Bordley (1941) have been published by Pickering, Roberts and Sowry (1954).While several workers report good agreement between systolic blood-pressure determined by the intra-arterial and that by the cuff method, there is disagreement over which of the two phases (phase 4, muffling, or phase 5, disappearance) represents the true diastolic pressure. Ragan and Bordley (1941) state that the pressure represented by sudden muffling (phase 4) of the Korotkoff sounds was usually higher than the intra-arterial pressure. Hamilton, Woodbury, and Harper (1936) found the diastolic pressure to be 9 mm. higher than the intra-arterial pressure when muffling was used as the end-point. Steele (1942) noted that the final cessation of sounds approximated to the intra-arterial diastolic pressure more closely than did muffling. However, Roberts, Smiley, and Manning (1953), using a strain-gauge manometer and an electromanometer (condenser microphone), concluded that muffling of the sounds bears a more constant and close relation to the " true " diastolic pressure. Van Bergen, Weatherhead, Treloar, Dobkin, and Buckley (1954) came to the same conclusion using a standard resistance wire pressure-transducer. The latter workers found that the disappearance of sound grossly underestimated the intra-arterial diastolic blood-pressure.Recent work (Holland, 1963 ;Rose, Holland, and Crowley 1964) has shown that blood-pressure measured by a normal sphygmomanometer can be affected by observer bias. The present comparisons of intra-arterial with cuff pressure were made using a London School of Hygiene sphygmomanometer (Holland, 1963) to avoid the possibility of observer bias. MethodIntra-arterial brachial-artery pressure was measured in the right arm by use of a Hansen (1949) capacitance manometer. This method has been utilized by Sharpey-Schafer (1955) Before starting the investigation the blood-pressure of subjects was measured simultaneously in both arms by two observers by connecting two cuffs to a common manometer via a T-junction. In no case was the difference between left and right arms greater than 5 mm. Hg.Intra-arterial blood-pressure was measured continuously during the course of the experiment. Cuff blood-pressure was

Recommendations for Blood Pressure Measurement in Humans and Experimental Animals

“…30,31 The range of discrepancies is quite striking: One author commented that the difference between the 2 methods might be as much as 25 mm Hg in some individuals. 32 There has been disagreement in the past as to whether phase IV or V of the Korotkoff sounds should be used for recording diastolic pressure, but phase IV tends to be even higher than phase V when compared against the true intra-arterial diastolic pressure and is more difficult to identify than phase V. There is now general consensus that the fifth phase should be used, except in situations in which the disappearance of sounds cannot reliably be determined because sounds are audible even after complete deflation of the cuff, for example, in pregnant women, patients with arteriovenous fistulas (eg, for hemodialysis), and aortic insufficiency.…”

An evaluation of the avionics pressurometer iii 1978 at home and in hospital

“…A single high casual blood pressure reading does not necessarily mean that a patient will have sustained hypertension. The reason for this is that the indirect method may differ from "true" (intra-arterial) blood pressure (Holland and Humerfelt, 1964;Raftery and Ward, 1968;Ragan and Bordley, 1941;Roberts et al, 1953;Steele, 194 1 -1942) and the pressure may have been raised by the stress of the measurement. In addition, the single measurement does not relate to the behavior of the blood pressure throughout the day.…”

Radio-Telemetry in Biomedical Research - Radio-Telemetry Blood Pressure Measurements in Animal Models of Hypertension, How It Revolutionized Hypertension Research

“…Other technologies and automated devices are also available, and the interested reader is directed to the review by Pickering et al (2005) for details. Of note, the Korotkoff technique tends to underestimate the systolic blood pressure and overestimate the diastolic blood pressure when compared to intra-arterial pressure (Holland & Humerfelt, 1964). With technology advances, battery-powered automated devices are now available to measure and record ambulatory blood pressure.…”