Age-Related Changes in Cerebral Hemodynamics in Children Undergoing Congenital Cardiac Surgery: A Prospective Observational Study.

OBJECTIVE

To explore age-related cerebral hemodynamic characteristics before and after pediatric cardiac surgery.

DESIGN

Prospective observational study.

SETTING

Single-center study based at a tertiary care center in Shanghai, China.

PATIENTS: Fifty-three children with congenital heart disease (CHD) aged zero-to-six years undergoing cardiac surgery with cardiopulmonary bypass were enrolled, and 44 children finally were analyzed.

INTERVENTION: Cerebral hemodynamics were measured by transcranial color-coded duplex sonography in the right temporal window before and after surgery. The resistance index (RI), pulsatility index (PI), and cerebral blood flow velocity (CBFV), including time average maximum flow velocity (Vtamax), mean blood flow velocity (Vmean), and the peak systolic flow velocity (Vpeak), of the right middle cerebral artery (MCA) and regional cerebral oxygen saturation (rScO2) of the right frontal lobe were measured and analyzed. Heart rate and mean arterial pressure were also recorded during ultrasound.

MEASUREMENTS AND MAIN

RESULTS

RI and PI decreased exponentially with age before and after cardiac surgery. While PI remained unchanged after cardiac surgery, RI was significantly reduced. Furthermore, RI reduction after cardiac surgery was more significant in children >18 months compared to those ≤18 months. CBFV of the right MCA also showed exponential increase with age, but rScO2 linearly increased. Cardiac surgery significantly changed the cerebral hemodynamics, but it did not affect rScO2 in children regardless of age.

CONCLUSIONS

Age-related cerebral hemodynamic changes exist in children with CHD. Cardiopulmonary bypass surgery led to greater cerebrovascular dilation in children aged ≤18 months than those >18 months.