Clinical

Patent ductus venosus flow affects liver function in preterms

Last Updated: 2006-05-16 14:22:34 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Patent ductus venosus (PDV) in preterm infants influences a number of key liver functions, a new study from Japan shows.

Portosystemic venous shunt with a high shunt ratio has a well-known effect on liver function, Dr. K. Murayama of Chiba Children's Hospital and colleagues note, but the effect of shunts with a lower shunt ratio on liver function are not as clear, and there has been little research on liver function and PDV before functional closure.

To investigate, Dr. Murayama and colleagues evaluated 167 newborns with gestational ages ranging from 29 to 41 weeks, dividing them into three groups: group I, 29 to 32 weeks gestation; group II, 33-36 weeks; and group III, 37-41 weeks.

Infants in group I had a higher volume of blood flow through the ductus venosus and functional closure occurred later.

At 3 and 7 days of age, plasma ammonia was significantly higher in group I infants compared with infants in the other two groups, and it was higher in group II infants than in group III infants at both time points. Total bile acid was highest in group I infants at 3 days of age, but there was no significant difference among the groups after 7 days.

Flow volume, measured by serial ultrasonography, correlated with plasma ammonia and total bile acid concentrations in group I at 3 and 7 days of age, and in group II at 3 days of age.

All three groups showed a correlation between flow volume and percentage hepatoplastin at 3 days. Only group III showed an association between flow volume and galactose and galactose 1-phosphate concentrations at 3 days, which the researchers attribute to a higher milk intake.

"These results strongly suggest that PDV influences neonatal liver functions involving ammonia detoxification, bile acid regulation, and galactose metabolism, and that the magnitude of the effect differs with gestational and postnatal age," the researchers write. The link between flow volume and hepatoplastin percentage, they add, suggests that neonates with high PDV flow are more susceptible to hemorrhage.

They conclude: "The pathological significance of PDV should be highlighted in clinical practices dealing with neonates."

Arch Dis Child Fetal Neonatal Ed 2006;91:F175-F179.