Neonatal abdominal aortic thrombosis

Nurses' guide to early detection of umbilical arterial catheter complications in infants

Umbilical arterial catheters (UAC) are routinely used in the care of critically ill newborns. Complications related to UACs include vascular compromise, hemorrhage, complications related to malposition, severance of the catheter itself, and infection. This article is Part II in a series dedicated to assessing infants with an umbilical catheter. Part I focused on infants with umbilical venous catheters; this article will focus on the physical assessment relevant to infants with an UAC. Complications related to UACs can occur during any phase of treatment: insertion, while indwelling, or after discontinuing the catheter. Review of clinical signs of complications along with clinical photographs, will assist caregivers in promptly recognizing UAC-related complications.

Thrombolytic therapy in children

Thrombolysis is increasingly considered a treatment option in newborns and children with arterial and venous thromboembolic events, or occluded central venous lines. However, no uniform recommendations are available with regard to indications, drug of choice, route of administration, and dosing regimen. Thus, several protocols are used for the different thrombolytic agents, leading to differing outcome with respect to the effectiveness of therapy and bleeding complications. This article will summarize the available information on the use of thrombolytic agents in newborns and children, focussing on the potential indications, efficacy and safety profiles, and evidence supporting dosing schedules.

Thrombolytic therapy in infants and children

Thrombolytic therapy is being increasingly used to treat various cardiac and other disorders in the pediatric population. The use of thrombolytic therapy in thrombosis following cardiac catheterization, aortic thrombosis, right atrial and caval thrombosis, pulmonary embolism, thrombosed prosthetic valves, thrombosed Blalock-Taussig shunts, and other disorders is delineated. Special issues of the newborn are discussed. A wider appreciation of the indications and contemporary experience would help in optimizing the use of thrombolytic therapy in children.

High-dose urokinase therapy in newborn infants with major vessel thrombosis

The effectiveness of urokinase therapy for thrombosis in children, particularly in newborn infants, has not been established. We report our experience with the local administration of high-dose intrathrombus urokinase in two newborn infants. One infant had aortic thrombosis and the other, thrombosis of the right femoral artery. The known abnormalities in the newborn's fibrinolytic mechanism provide the rational basis for the therapeutic use of high doses of plasminogen activators. No significant abnormalities of our patients' fibrinolytic systems were found, and effective thrombolysis was achieved. A literature review of the use of urokinase therapy for thrombosis in children reveals great disparities in dosage and outcome. We believe that fixed-dose regimens should be replaced by individually adjusted thrombolytic therapy and that the need for higher doses of urokinase in newborns should be studied further.

Favorable outcome of neonatal aortic thrombosis and renovascular hypertension

Fifteen children with renovascular hypertension as a result of aortic thrombosis were followed for a mean of 26 months (range 5 to 58 months) to determine outcome. As neonates, all patients had hypertension and elevated plasma renin activity. Of 11 patients studied with radionuclide renography and scintigraphy, 10 had abnormal renal blood flow; three had complete absence of unilateral perfusion. On follow-up examination all children were normotensive; five children ages 5 to 24 months required antihypertensive medication. Of 15 children, 14 had normal statural growth; all had normal serum creatinine, plasma renin activity, and calculated glomerular filtration rate values. Patients with complete absence of renal perfusion unilaterally remained functionally anephric; children with less severe perfusion deficits had improved perfusion as shown by radionuclide renography and scintigraphy. We believe that many patients with aortic thrombosis and renovascular hypertension who have had aggressive antihypertensive therapy in the neonatal period will have good renal function and increased perfusion to the affected kidney 2 years later.

The hypoplastic left heart syndrome: evidence of preoperative myocardial and hepatic infarction in spite of prostaglandin therapy

From February, 1983, to November, 1984, 11 infants with hypoplastic left heart syndrome were managed medically prior to operative intervention. Only 2 of the 11 infants appeared to be in mild distress at birth. Despite relatively normal Apgar scores, 9 of the infants were seen in shock. All patients were managed medically with fluid restriction, diuretics, and the institution of prostaglandin E1. There was a marked improvement in arterial pH from a mean value of 7.13 prior to prostaglandin to 7.42 following prostaglandin infusion. There was also a dramatic decrease in the serum creatinine level from a mean pretreatment level of 1.5 mg/dl to 0.7 mg/dl following infusion. Ten of the 11 infants were operated on at a mean age of 4 days with a Norwood or conduit procedure. Three infants who died at 3, 13, and 24 days of age had sustained myocardial infarctions prior to operation. Three patients also had multiple infarcts of the liver. Three patients are alive 23, 22, and 6 months after operation, and are growing and developing normally. The ability to maintain the infant with hypoplastic left heart syndrome in a stable hemodynamic condition has made surgical palliation a realistic option for this otherwise fatal anomaly. Nevertheless, preoperative infarctions of the heart and viscera continue to play a major role in mortality.

Neonatal aortic thrombosis: recent experience

To evaluate the course, use of diagnostic modalities, management, and outcome of aortic thrombosis associated with umbilical artery catheterization, we reviewed 20 cases of aortic thrombosis diagnosed by ultrasonography (n = 16) or aortography (n = 4) over 4 years. Fourteen of 20 infants had severe perinatal asphyxia, suggesting that asphyxia predisposes to aortic thrombosis. Ultrasonography provided information about the size, location, and configuration of the thrombus and was useful in following thrombus size with therapy. Radionuclide renography-scintigraphy demonstrated abnormal renal function in all 11 patients scanned. Six patients with minor thrombosis (hypertension as the only sign) improved without specific therapy. Nine infants had moderate thrombosis (multiple signs but normal urine output); all survived with a variety of therapies; two were not given anticoagulant or fibrinolytic agents; three improved with heparin alone; and one had surgery without recurrence of the thrombus. Resolution of moderate thrombosis followed streptokinase therapy in two of three infants. All five babies with anuria from major thrombosis died. Hepatic infarction associated with aortic thrombosis was found in three of three autopsies.

Congestive heart failure and absent femoral pulses in newborns without coarctation of the aorta

Two infants with thrombosis of the abdominal aorta are discussed. In each case the presentation was indistinguishable from that in coarctation of the aorta, with heart failure and absent femoral pulses. Surgery in one infant successfully relieved the obstruction. The diagnosis may not be suspected from the history. Aggressive management is indicated.