Loose Cuff Hypertension

Abstract

In this study, an analysis of the effects of cuff looseness on mean blood pressure readings was performed. Using a standard adult blood pressure cuff, pressure readings were taken on each arm at a cuff looseness of 0, 2, 4, and 6 cm beyond patient arm circumference. The cuff was then switched to the opposite arm and the procedure repeated. Blood pressure readings taken from the left arm with the cuff at an appropriately snug fit served as the reference. Increasing cuff looseness simulates the possibly incorrect blood pressure cuff placement by health care workers in the clinical setting. Data from 24 subjects support the claims that mean blood pressure increases with respect to increasing cuff looseness. It was shown that measurements taken on left and right arms will result in significantly different blood pressure readings (p < 0.001). It is therefore crucial to properly place the cuff at a snug fit on the patient's arm for each measurement procedure, to prevent false readings. Lack of consistent cuff size and snugness procedures can lead to misdiagnosis of hypertension, acute patient discomfort, and inconvenient costs to the patient and health care provider.

An audit and suggested guidelines for in-patient blood pressure measurement

“…For the correct size cuff, the bladder width should be at least 40%, and its length 80% (but not more than 100%) of the arm circumference. Overcuffing has been reported to cause a sharp pinching and may simulate a cuff that is too narrow to record accurately [23]. When the bladder is too small (undercuffing), it is possible to overestimate BP [22].…”

Automated ‘oscillometric’ blood pressure measuring devices: how they work and what they measure

“…Missing oscillometric waveform values require different degrees of interpolation relative to deflation rate. Although accuracy may not always be compromised [ 70 ], error is expected to increase at faster deflation rates [ 56 , 71 ] Extracting the oscillometric waveform Different filtering methods used to extract waveform pulsations can distort the shape of the extracted pulses and the oscillometric waveform, thus changing BP estimations [ 72 , 73 ] Constructing the oscillometric waveform envelope Several signal processing methods can be used to construct the oscillometric waveform envelope, and this creates variability in waveform envelope morphology as well as different BP estimations [ 55 ] BP algorithms There is a large variety of algorithms to estimate BP, many of which are patent protected for each individual automated BPMD, and have variable performance characteristics [ 50 , 55 ] that are difficult to independently scrutinise. Algorithms are empirical and may not account for individual physiological variability in modifying factors such as arterial stiffness [ 74 ].…”