P24 BRACHIAL AND CENTRAL SYSTOLIC BLOOD PRESSURES FROM TWO OSCILLOMETRIC DEVICES (SPHYGMOCOR AND MOBIL-O-GRAPH) OVERESTIMATE HIGH FIDELITY INTRA-ARTERIAL MEASUREMENTS IN CHILDREN AND ADOLESCENTS: RESULTS OF THE KIDCOREBP STUDY

Abstract

Objective: This study investigated the accuracy of two oscillometric devices for measuring brachial and central blood pressures (BP) in children and adolescents, using high fidelity intra-arterial measurements as a gold-standard reference. Methods: 57 children and adolescents aged 9.5 ± 4.6 years (mean ± SD, range 3 to 17, 74% <13 years) without aortic obstruction were recruited. A catheter was inserted into the ascending aorta via the femoral artery during a clinically-indicated procedure. Aortic BP was measured with a Verrata wire (Philips Volcano), along with brachial BP via two oscillometric devices: SphygmoCor XCEL (AtCor Medical, N = 51) and/or Mobil-o-Graph (MoG, IEMGmbH, N = 40). Intra-arterial brachial systolic BP was derived by calibrating the brachial pulse waveform (measured via tonometry after wire removal) to aortic mean and diastolic BP. For MoG, central pressure was derived through standard systolic-diastolic calibration (MoGC1) as well as mean-diastolic calibration (MoGC2). Results: Mean±SD differences between device and intra-arterial BP are presented in the Table. There was moderate correlation between device and intra-arterial brachial systolic BP (R = 0.58 XCEL, R = 0.47 MoG, P < 0.01) and central systolic BP (R = 0.69 XCEL, R = 0.64 MoGC1, R = 0.43 MoGC2, P < 0.01). Intra-arterial central-to-brachial pulse amplification factor was 1.17 ± 0.16 (range 0.88 to 1.55), but there was no correlation between device and intra-arterial amplification (R = 0.07 XCEL, R = 0.07 MoGC1, R = 0.19 MoGC2, P > 0.18). Results in sub-groups ≥13 and <13 years were similar. Conclusion: Both oscillometric devices overestimated brachial and central systolic/pulse BP, exceeding the validation criteria of 5 ± 8 mmHg, and there was no correlation between intra-arterial and device-derived central-to-brachial pulse amplification. Diastolic BP was acceptable.