TECHNICAL difficulties which are encountered during surgical operations for patent ductus arteriosus arise directly or indirectly from dissection of the ductus. In children the ductus is relatively long and has a small lumen. In adults, however, it is often short, has a large lumen, and may therefore be difficult to isolate. The danger is increased if the ductus is friable or is surrounded by adhesions. Dissection of the posterior wall is particularly likely to tear the ductus and cause hemorrhage. Whether the procedure contemplated is division of the ductus, as Gross1 advocates (Fig. 1), or ligation by the Blalock2 method (Fig. 1), the ductus must first be carefully dissected out. If it has a large lumen, even the procedure of ligation may result in tearing of the wall when the ligature is drawn tight.
Hemorrhage, which occurs during operations for the patent ductus arteriosus, may be due not