Prostaglandin E1 opens the ductus venosus in the newborn lamb.

There is in vitro evidence that the ductus venosus of the fetal and newborn lamb relaxes to administration of E-series prostaglandins. We performed this study to determine whether the ductus venosus of the newborn lamb could be reopened by an infusion of prostaglandin E1. Fifteen lambs between 4 and 28 h of life and six lambs between 42 and 96 h of life had portal angiograms to determine whether the ductus venosus was patent. Ten of the lambs between 4 and 28 h of age had a closed ductus venosus as did all of the lambs between 42 and 96 h of age. The lambs with a closed ductus venosus received an infusion of either prostaglandin E1 or normal saline followed by repeat portal angiography. In the 4- to 28-h-old lambs, prostaglandin E1 opened the ductus venosus in each of the five lambs who received it, while saline did not in any of the five who received it. In the 42- to 96-h-old lambs, neither prostaglandin E1 in four lambs nor saline in two lambs opened the ductus venosus. Prostaglandin E1, then, reopens the ductus venosus in the newborn lamb during the first day of life. We speculate that prostaglandin E1 may be useful in reopening the ductus venosus in certain newborn infants such as those requiring catheterization of the right atrium and those with total anomalous pulmonary venous return below the diaphragm.