Radial artery blood pressure measurement in neonates: an accurate and convenient technique in clinical practice

Abstract

To achieve accurate blood pressure measurement through radial artery catheters in infants, we previously developed an experimental high-fidelity catheter-manometer system (CMS). As this system lacks facilities for flushing and for blood sampling, we aimed to further develop this technique in order to make the system suitable for clinical practice. In addition, we aimed to develop methods to automate processing of the pressure wave forms. The high-fidelity system to be improved consisted of a 24 Gauge catheter, a threeway stopcock and a tip-manometer. We inserted this system in the catheter-manometer system as routinely used i.e. the remaining end of the stopcock was connected to the fluid-filled CMS as used routinely. This combined system became clinically applicable, since blood samples could be obtained and flushing could be performed. The measurement chain was completed by application of a modified physiological monitor and a computerized method to analyze pressure wave forms. In this manner accurate beat-to-beat pressure parameters were obtained. This technique was applied to 25 neonates admitted for intensive care and requiring arterial access. Gestational age of these infants ranged from 25-40 (median 29) weeks and birth weight ranges from 500-3375 (median 1060) grams. In all infants the technique was found to be convenient and the high-fidelity blood pressure measurements were performed without any problems. The advantage of the present system is the potential for both correct intermittent recordings of arterial wave forms in close relation to clinical condition and for the establishment of accurate radial artery beat-to-beat pressure values in clinical practice.

Feasibility of Noninvasive Continuous Finger Arterial Blood Pressure Measurements in Very Young Children, Aged 0–4 Years

“…In addition, we observed a good correlation between finger cuff-derived BP values and arterial BP values. Apparently, compared with adults, the peripheral BP waveforms and values in infants seem to deviate less from central pressure (22,23).…”

Tracking of brachial and central aortic systolic pressure over the normal human lifespan: insight from the arterial pulse waveforms

“…In infancy, the upper limb arterial pressure wave has low amplitude (~20 mm Hg) with SP around 60 mm Hg 29 (Fig. 3).…”

“…Pressure waves of infancy were taken from published paper by Gevers et al . ; 29 pressure waves between 2 and 20 years were calculated from the ensemble‐averaged radial waveforms and aortic derived from radial pressure for all male and female children using SphygmoCor (AtCor Medical, Sydney, NSW, Australia) system; 10,12 pressure waves of a 90‐year‐old woman were recorded using SphygmoCor system and shown as comparison to pressure waves recorded in children. Children pressure waves according to their age group: 2 years (1 male), 3–5 years (5 males), 6–10 years (14 males and 3 females), 11–15 years (16 males, 6 females), and 16–20 years (2 males, 1 female).…”

Bisferiens Peaks in the Radial Artery Pressure Wave in Newborn Infants: A Sign of Patent Ductus Arteriosus

“…The system is shown in Figure 2, and a complete description of the tiptransducer system is found in Hack et al (6). The remaining end of the three-way stopcock was connected to the clinically used fluid-filled manometer system for continuous flushing, for blood sampling, and for usual pressure monitoring as described previously (12). The high fidelity measurement system was connected to a physiologic monitor (Hewlett Packard 78834A, Andover, MA), which was modified to pass signals up to 30 Hz (75 Hz Bessel filter, 36 dB/octave).…”