Disagreement of the two oscillometric blood pressure measurement devices, Datascope Accutorr Plus and Omron HEM-705CP II, and bidirectional conversion of blood pressure values

Abstract

Oscillometric blood pressure (BP) measurement devices frequently replace the standard mercury sphygmomanometer. Comparisons of oscillometric devices are rare, but their agreement is important to ensure comparability of BP data. This study aims to compare two oscillometric devices, Datascope Accutorr Plus and Omron HEM-705CP II, and to develop BP conversion models. A sample of 109 adults aged 21-64 years were subjected to alternate same-arm BP measurements according to the International Protocol revision 2010 for the validation of BP measuring devices in adults of the European Society of Hypertension. A total of 327 BP measurement pairs were obtained. Datascope systolic blood pressure (SBP) pairs, in mmHg, were optimal (<120) for n=188, prehypertensive (120-139) for n=107, and hypertensive (≥140) for n=32 [diastolic blood pressure (DBP)<80 (n=261)/80-89 (n=57)/≥90 (n=9)]. The mean Omron values were higher and the difference increased with BP [mean differences, Omron minus Datascope, within BP ranges were (in mmHg): SBP 1.1±4.7, 3.0±5.5, and 9.3±6.7 and DBP 0.2±3.3, 2.3±3.4, and 5.1±3.9] and pulse pressure (>50 mmHg, SBP difference 5.6±6.3). The prevalence of hypertensive BP was 11% with Omron and 5% with Datascope. Bidirectional conversion models of SBP and DBP values include BP, pulse pressure, age, sex, and the difference in the ratio of cuff width to arm circumference. The disagreement in oscillometric devices can reach a magnitude that could be of interest for clinical and epidemiological contexts. Conversion formulas with BP, pulse pressure, sex, age, and the cuff width to arm circumference ratio may help to improve comparability.