Validation of pulse dynamic blood pressure measurement by auscultation

BACKGROUND: The accurate measurement of arterial blood pressure is essential for the diagnosis and treatment of hypertension. The development of new automated methods of measurement that provide reliable determinations of blood pressure should be valuable in the assessment of hypertension not only in the clinic or hospital but also, in the home for self-monitoring. DESIGN: We evaluated a noninvasive method for the measurement of systolic and diastolic blood pressures in 132 subjects. METHODS: Measurements obtained using the pulse dynamic method of blood pressure determination were validated with simultaneous manual measurements. Two qualified nurses used Korotkoff sounds to determine systolic (phase I) and diastolic (phase IV) blood pressures according to the Association for the Advancement of Medical Instrumentation 1987 guidelines. RESULTS: Inter-nurse variability was 2.7 +/- 4.1 mmHg (mean +/- SD) for systolic blood pressure and 4.0 +/- 3.7 mmHg for diastolic blood pressure and correlations were r = 0.98 and 0.94, respectively. We observed excellent agreement between auscultatory and pulse dynamic methods for systolic (127 +/- 21 versus 132 +/- 20 mmHg; r = 0.97) and diastolic (72 +/- 10 versus 71 +/- 10 mmHg; r = 0.89) blood pressures. Bland-Altman analysis demonstrated that there was a mean difference (reference-device) between the two methods of - mmHg (pulse dynamic value higher) and SD of 5 mmHg for systolic blood pressure and a mean difference of 1 mmHg (pulse dynamic value lower) and SD of 5 mmHg for diastolic blood pressure. CONCLUSION: The results of this study demonstrate that this noninvasive method of measurement of blood pressure is accurate and reliable and should therefore be appropriate for the evaluation of hypertension both in the home and in clinical settings.