Patent ductus arteriosus in premature infants. Indications for surgery.

In order to establish more objective criteria for surgical intervention, the literature and our clinical experience with operative closure of patent ductus arteriosus in 11 premature infants was reviewed. A wide range of age at the time of operation underscored the spectrum of clinical presentation and the difficulty of interpreting the course of therapy. The presence of a typical continuous murmur established the diagnosis of patent ductus arteriosus in patients with respiratory distress syndrome. Cardiac catheterization confirmed the diagnosis and provided quantitation of the left-to-right shunt flow through the ductus arteriosus in 6 patients but did not influence the decision to operate. Progress of the clinical course as determined by the heart size on chest roentgenogram and the presence of hypercarbia (Paco2greater than60 mm. Hg) after respiratory assistance and medical decongestive measures were the two most helpful signs indicating the need for surgical intervention.