A simple, noninvasive method to investigate vascular characteristics in children

Palpation of pulses is an ancient clinical technique. In modern medical terms, arterial pulse analysis permits the evaluation of vascular characteristics, the important parameters for study of the properties of vessels. However, the various parameters used to describe the vascular characteristics have been conventionally deriving from expensive, invasive, and complicated methods and involving complex computations. The authors designed, therefore, a simple, noninvasive system to evaluate vascular characteristics. The system consisted of two units of pressure transducer for simultaneous recording of two peripheral arterial pulses, an analog signal processor, an A/D converter, and a personal computer. The vascular characteristics were analyzed by use of the Windkessel model and cross-correlation function. The analysis program was designed by members of this team. Through this system, systemic arterial compliance and pulse wave velocity can be obtained. Thirty-five children (11 normal children and 24 children with various stable, mild congenital heart diseases) were enrolled for data analysis. For these 35 children without hypertension or other clinically apparent arterial disease, the pulse wave velocity in the upper limb as between 3.7 and 16.8 m x sec-1, with a mean +/- standard deviation of 9.3 +/- 3.3 m x sec-1. The arterial compliance among the 11 normal children was between 0.72 and 1.72 mL x mmHg-1 x m-2 with a mean of 1.15 mL x mmHg-1 x m-2; both were consistent with the previously reported values obtained from complex methods. This system provides data comparable with those obtained from invasive methods. In the past, the arterial characteristics could not be extensively studied owing to the invasive nature of the conventional methods. This new, simple, convenient noninvasive system will thus provide a convenient method for clinical use in evaluating the vascular characteristics of patients, especially of children.