Background: Continuous beat-to-beat blood pressure monitoring permits the rapid detection of blood pressure fluctuations for cardiovascular reflex testing and clinical haemodynamic monitoring. In adults, this can be achieved noninvasively with high accuracy, using finger blood pressure monitoring with volume clamp photoplethysmography. However, data are lacking on the validity of finger blood pressure monitoring in children compared to the gold standard - invasive intra-arterial blood pressure monitoring.
Aim: We aimed to evaluate the accuracy of novel noninvasive index and middle finger arterial pressure (FinAP) measurements in children.
Methods: Using prototype paediatric finger cuffs, we compared: mean differences, bias and limits of agreement (Bland-Altman analyses); cumulative percentage differences [clinical grade A-D (based on the percentage of heartbeats in agreement with the standard)]; and waveform morphology (regression analysis and smoothing) between both raw FinAP (Finapres NOVA) and reconstructed finger-brachial arterial pressure (reBAP) compared to intra-arterial blood pressure measurements.
Results: Eighteen children were tested (aged 3-13 years; 12 male), with data from 13 included in the analysis. The bias for reBAP for the middle finger was 1.8±6.9, 0.3±6.1 and 0.4±5.3 mmHg for systolic, diastolic and mean arterial pressure, with clinical grades of C, B and A, respectively. reBAP improved numerical accuracy, but reduced waveform morphological agreement.
Conclusion: Middle finger arterial measurements with waveform reconstruction provide an acceptable surrogate for invasive intra-arterial recording in children. Finger blood pressure monitoring is a novel comfortable, convenient and accurate alternative approach for noninvasive beat-to-beat blood pressure monitoring in children.