Unreliable oscillometric blood pressure measurement: prevalence, repeatability and characteristics of the phenomenon

Abstract

Oscillometric devices are being widely used for ambulatory, home and office blood pressure (BP) measurement. However, even successfully validated oscillometric devices fail to provide accurate measurements in some patients. This study investigated the prevalence, the reproducibility and the characteristics of the phenomenon of unreliable oscillometric BP (UOBP) measurement. A total of 5070 BP measurements were obtained simultaneously (Y connector) using a professional oscillometric device (BpTRU) and a mercury sphygmomanometer in 755 patients (1706 visits). UOBP readings were defined as those with 410 mm Hg difference (systolic or diastolic) between the two methods. UOBP was found in 15% of systolic and 6.4% of diastolic BP measurements. In all, 18% of the participants had UOBP in their first but not their second visit, or the reverse. However, 49% of these participants had at least one more UOBP visit after their second visit within the study database. Patients with persistent UOBP were more likely to be female and had lower arm circumference. The systolic BP discrepancy between the two methods was associated with pulse pressure (r ¼ 0.41) and inversely with diastolic BP (r ¼ 0.40) and arm circumference (r ¼ 0.30), whereas the diastolic discrepancy with diastolic BP (r ¼ 0.61) and inversely with pulse pressure (r ¼ 0.32). There was a consistent significant trend for larger systolic BP discrepancy and smaller diastolic from the lower to the higher pulse pressure quintile (Po0.0001). A decreasing arm circumference was a significant predictor of persistent UOBP. These data suggest that the UOBP measurement is particularly common, not very reproducible and mainly affected by pulse pressure and arm circumference.

Noninvasive Blood Pressure Measurement in Maintenance Hemodialysis Patients: Comparison of Agreement between Oscillometric and Finger-Cuff Methods

“…However, BP readings provided by semi-automatic oscillometric instrument eliminated the observer's bias related with the use of the manual auscultatory technique [9,15,16,53] .…”

Short and longer term repeatability of ballistocardiography in a sitting position with EMFi sensor

“…A reason for the non-correlation between BP and PWV might be that BP measured from the brachial artery is not identical to the systolic and diastolic pressures found in the aorta [12]. Recently oscillometric BP measurement has been regarded as unreliable [22]. However, it is not excluded that the influence of the changed PWV values on the BCG signal and the general health of a measured person may explain variations between studied persons especially in longer time intervals.…”

Letters to the editor

“…6 However, for the sake of redressing the imbalance between those who have mastered the skill of auscultatory blood pressure measurement and those who have not, automated oscillometric devices have now become the ones routinely used in many other healthcare settings for documenting the blood pressure which goes on permanent record in the medical notes, notwithstanding the fact that in a recent study, where a total of 5,070 blood pressure measurements were obtained simultaneously (Y connector) using a validated oscillometric device with Grade A status and a mercury sphygmomanometer, 15% of systolic and 6.4% of diastolic blood pressure measurements diverged by >10 mm Hg from the mercury standard. 7 Also, notwithstanding the Grade A status of the oscillometric device reported in the study, the consequences of its inherent aberrations 7 will probably be the same as those forecast after the analysis of the performance of nine non-ambulatory oscillometric devices belonging to the Grade A to D category of the British Hypertension Society four years previously. 8 The prediction was that 'patients with hypertension [could] erroneously be classified as non-hypertensive and treatment withheld' and that 'in treated hypertensive patients the necessary adaptation of treatment will not take place…'.…”