Abstract P354: Performance of Different Oscillometric Blood Pressure Algorithms in Patients with Chronic Kidney Disease

Abstract

Objective: The extent to which different oscillometric blood pressure (BP) algorithms differ in how they derive BP in patients with chronic kidney disease (CKD) is unknown. We compared the performance of three different oscillometric algorithms against a known oscillometric reference standard in this patient population. Methods: Thirty intermittent hemodialysis (HD) patients and 30 stage 3 CKD (CKD) patients were recruited from a quaternary care, academic hospital in Edmonton, Canada. In random order, three sequential readings with an Omron HEM 907XL device and three sequential readings with a laptop-driven oscillometric device capable of detecting and recording oscillometric waveforms were obtained 30 seconds apart. The mean of each three reading set was used for analyses. Oscillometric algorithms (two fixed-ratio and one slope- based) were applied to the raw oscillometric data to derive BP. Paired t-tests were used to assess for statistical significance at the 0.05 level. Results: Mean age was 63.4 ± 16.3 y (HD group) and 65.9 ± 10.7 y (CKD group); percent female was 37% (HD) and 47% (CKD); mean BMI was 28.3 kg/m 2 (HD) and 30.3 kg/m 2 (CKD). Over 80% of participants in each group had hypertension. BP comparisons are summarized in Table 1. Conclusions: Varying the type of oscillometric algorithm results in markedly different systolic BP estimates in patients with CKD. The fixed-ratio algorithm produced results most comparable to the Omron device. These findings help clarify why different devices using different algorithms produce different results in patients with CKD.