[Doppler preoperative evaluation of the prevalence of functional abnormalities of palmar arches in children].

Thromboembolic events and inadequate palmar collateral circulation are the two main mechanisms of hand ischaemia following radial artery cannulation. The latter cause may be detected in adults with Allen's test, which is difficult to perform and to interpret in children. Therefore we investigated preoperatively in children the permeability of palmar arches with doppler ultrasound, prior to radial artery cannulation. Thirty-five children (20 M/15 F), 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 thumb were identified. Alterations in flow caused by compression of the radial artery were noted. Results were expressed in qualitative terms: functional arch (normal doppler), moderately functional or non-functional arch (abnormal doppler). In the latter cases, the artery was not cannulated. An anomaly in one or both palmar arches was seen in 43% of children (95% confidence interval: 25-60%). The incidence was comparable on both sides (right: 34%; left: 31%) with a mean probability of 33% (95% confidence interval: 17-49%). The probability 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 incidence of a bilateral anomaly (23%).(ABSTRACT TRUNCATED AT 250 WORDS)