PREOPERATIVE DIAGNOSIS WITH DOPPLER ULTRA SOUND OF PALMAR ARCHES FUNCTIONAL ANOMALIES IN CHILDREN

Thromboembolic events and inadequate palmar collateral circulation are the two main mechanisms of hand ischaemia following radial artery can nulation. The latter cause may be detected in adults with Alien's test , which is difficult to perform and to interpret in children. Therefor e we investigated preoperatively in children the permeability of palma r arches with doppler ultrasound, prior to radial artery cannulation. Thirty-five children (20 M/15 Fl, aged between 6 months and 14 years ( mean = 4.2 years) were scheduled for doppler ultrasound study of their palmar arches before undergoing a major neurosurgical procedure. This study was performed with a 8 MHz directional doppler probe according to Marcillon's technique. Blood flow in superficial palmar arch and in pad of the thumd were identified. Alterations in flow caused by compr ession of the radial artery were noted. Results were expressed in qual itative terms: functional arch (normal doppler), moderately functional or non-functional arch (abnormal doppler). In the latter cases, the a rtery was not cannulated. An anomaly in one or both palmar arches was seen in 43 % of children (95 % confidence interval: 25-60 %). The inci dence was comparable on both sides (right: 34 %; left: 31 %) with a me an probability of 33 % (95 % confidence interval: 17-49 %). The probab ility of a controlateral anomaly, when one hand was abnormal, reached 70 %, e.g., twice that of the first hand (p < 0.01). This indicates a relatively low incidence of asymmetry (20 %) and therefore a high inci dence of a bilateral anomaly (23 %). The mean age of subjects with at least one abnormal palmar arch was significantly lower than the mean a ge of the children without an anomaly (m +/- SEM) 2.5 +/- 0.6 yrs vs 5 .5 +/- 0.7 yrs (p < 0.01). Conversely, sex-ratios were comparable in b oth groups (0.55 vs 0.6, p = 0.77). This doppler ultrasound study demo nstrated a high rate of children with at least one inadequate palmar a rch. Low age seems to be a predisposing factor to functional anomalies . These results are in agreement with those obtained in neonates, demo nstrating a very high incidence (60 %) of abnormal doppler ultrasound examinations. Bilateral involvement led us to contra-indicate radial a rtery cannulation in nearly one out of four children. In conclusion, c onsidering the reliability of the doppler examination we recommend thi s technique which is useful in children prior to radial artery cannula tion, particularly when Alien's test cannot be performed or is abnorma l.