Non-invasive aortic blood flow measurement in infants during repair of craniosynostosis

Abstract

We have assessed the potential clinical benefit of a new echo-Doppler device (Dynemo 3000) which provides a continuous measure of aortic blood flow (ABF) using an aortic flowmeter and a paediatric oesophageal probe, during repair of craniosynostosis in infants under general anaesthesia. The data recorded included: ABFi (i = indexed to body surface area), stroke volume (SVi), systemic vascular resistance (TSVRi), pre-ejection period (PEP), left ventricular ejection time (LVET), mean arterial pressure (MAP), heart rate (HR) and central venous pressure (CVP). Data were collected: before (T1) and 3 min after skin incision (T2), at the time of maximal haemorrhage (T3) and at the end of the procedure (T4). Twelve infants (aged 7.0 (range 6-12) months) were included. ABFi, MAP and CVP were significantly lower at T3 compared with T1 (2.0 (0.8) vs 3.0 (0.8) litre min-1 m-2, 46.1 (5.8) vs 65.2 (8.9) mm Hg and 2.8 (1.6) vs 5.2 (2.1) mm Hg; P < 0.05). PEP/LVET ratio was significantly lower at T2 compared with T1 (0.25 (0.05) vs 0.30 (0.06)) and increased at T4 (0.36 (0.04); P < 0.05). These preliminary results suggest that this non-invasive ABF echo-Doppler device may be useful for continuous haemodynamic monitoring during a surgical procedure associated with haemorrhage in infants.