Effective thrombolytic therapy of aortic thrombosis in the small premature infant.

Aortic thrombosis in the very-low-birthweight premature infant has remained both a diagnostic and a therapeutic dilemma. Nine small infants were evaluated for symptoms of extremity and/or visceral ischemia. All were found to have aortoiliac thrombosis most likely related to indwelling umbilical artery catheters. Diagnostic and therapeutic options were evaluated. An angiogram obtained through the catheter was found to be the most effective diagnostic technique. Local infusion of intra-arterial streptokinase (50 U/kg/h) directly into the clot for 36 hours resulted in resolution of ischemic symptoms. No complications were encountered with the use of this protocol.