Numerical Assessment of the Effects of Ductus Arteriosus Closure on Cerebral Blood Flow Rate in Newborn Infants

The physiological changes within a few days after birth is vital importance for health of newborn infants. Ductus arteriosus, which is a vessel connection between aorta and pulmonary arteries, closes in the first day life of term infants. In this study, a lumped-parameter model was used to evaluate change of cerebral blood flow rate due to closure of ductus arteriosus within a 24 hour after birth in term infants. The model includes heart chambers, systemic circulatory system, pulmonary circulatory system and a complete circle of Willis. The cerebral blood flow rate was 122 mL/min in the cardiovascular system model simulating period right after birth and it increased to 151 mL/min in the cardiovascular system model simulating $24^{th}$ hour after birth. Also, the blood flow rate through internal carotid arteries increased from 47 mL/min to 58 mL/min and the blood flow rate through vertebral arteries increased from 14 mL/min to 17 mL/min. The results showed that the closure of the ductus arteriosus causes cerebral blood flow rate to increase in term infants.