Right atrial thrombosis in neonates receiving central venous lines after extracorporeal membrane oxygenation

Surgical repair of congenital diaphragmatic hernia during extracorporeal membrane oxygenation: hemorrhagic complications and the effect of tranexamic acid

Extracorporeal membrane oxygenation (ECMO) was incorporated in a strategy of delayed repair of congenital diaphragmatic hernia (CDH) and was used for preoperative stabilization in patients who were unresponsive to maximal conventional treatment. If ECMO was required for preoperative stabilization the diaphragmatic defect was repaired while the patient was on ECMO. In the early experience with this approach all patients suffered from bleeding complications. Therefore, we adopted the use of antifibrinolytic therapy with tranexamic acid (TEA) during and immediately after CDH repair on ECMO. The efficacy of TEA was studied in an unblinded study using historical controls by comparing the postoperative blood loss and the transfusion requirements of red blood cells (RBC) in patient groups treated without (n = 9) and with TEA (n = 10). Patients who received TEA had significantly less bleeding at the surgical site than patients not receiving TEA (57 v 390 mL, P = .005) and had significantly lower RBC transfusion requirements than patients not receiving TEA (1.13 v 2.95 mL/kg/h, P = .03). In the very first two patients of the TEA group we encountered fairly severe thrombotic complications. TEA may have contributed to those complications. Based on the authors' experience they conclude: (1) TEA is effective in reducing postoperative blood loss, hemorrhagic complications, and RBC transfusion requirements associated with CDH repair on ECMO. (2) TEA may be responsible for thrombotic complications. (3) The appropriate, empirically established, dosage and administration patterns of TEA for CDH repair during ECMO seem to be one bolus of 4 mg/kg TEA intravenously 30 minutes before the anticipated CDH repair and a continuous infusion of 1 mg/kg/h TEA during the 24 hours after CDH repair.

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.

Aminocaproic acid decreases the incidence of intracranial hemorrhage and other hemorrhagic complications of ECMO

Since the inception of extracorporeal membrane oxygenation (ECMO), hemorrhage has been a major complication often limiting its usefulness. This study was undertaken to evaluate the effect of aminocaproic acid (AMICAR), an inhibitor of fibrinolysis, on all hemorrhagic complications of ECMO including intracranial hemorrhage (ICH). In 1990, 49 neonates and 5 older children received ECMO therapy. None of these patients received AMICAR. In 1991, 51 neonates and 5 older children received ECMO. Forty-two of these patients who were considered to be at high risk for bleeding complications (preexisting or anticipated surgical procedures, preexisting ICH, or profound hypoxia, acidosis, coagulopathy, or prematurity) were given AMICAR. The remaining 14 low-risk neonates did not receive AMICAR, and for purposes of analysis were combined with the 1990 group. AMICAR was administered just prior to or after cannulation (100 mg/kg, intravenously) and was infused continuously at 30 mg/kg/h until decannulation. Except for the addition of AMICAR, the ECMO protocol was identical for these two patient groups. Patients who received AMICAR had significantly less bleeding while on ECMO (P = .03) and required fewer blood transfusions (P = .01) than patients not receiving AMICAR. This difference was most significant in the congenital diaphragmatic hernia and cardiac subgroups (P = .0001) and was not significant in the meconium aspiration subgroup (P = .1). The incidence of ICH in the neonatal subgroup was also significantly reduced with no patient on AMICAR developing a new or extending a preexisting ICH (P = .007). Reexploration of the cannulation site for bleeding was also reduced in the AMICAR-treated group but the difference failed to reach statistical significance.(ABSTRACT TRUNCATED AT 250 WORDS)

Successful treatment of fungal right atrial thrombosis complicating central venous catheterization in a critically ill child

A 9-year-old boy was admitted to our pediatric intensive care unit after multiple trauma. On the 17th day post trauma, he developed catheter-related sepsis with candidemia. After removal of the catheter and 6 days of unsuccessful intravenous antifungal therapy, conventional and transesophageal two-dimensional echocardiography was performed revealing a large right atrial thrombus. Surgical thrombectomy under cardiopulmonary bypass was performed and the patient recovered within a few days. Fungal right atrial thrombus is a rare, life-threatening complication of central venous catheterization. Two-dimensional echocardiography is a simple and effective diagnostic technique that should be performed when candidemia is detected. The proper therapeutic response depends on the findings of this examination. For a symptomatic patient with a large, mobile thrombus, we strongly recommend thrombectomy. Surgery not only allows removal of the mass and thus elimination of the mechanical complication but is also a key to management of infection.

Great vein and right atrial thrombosis in critically ill infants and children with central venous lines

We performed a retrospective review of echocardiographic data files of infants and children hospitalized in the Newborn and Pediatric Intensive Care Units. Echocardiograms were examined to detect the presence and evolution of great vein and right atrial thrombosis in patients with central venous lines. Thirty-seven patients were identified over a five-year period. Echocardiograms were performed, not routinely, but in response to specific indications including catheter malfunction, thrombocytopenia, persistent chylothorax, bacterial or fungal sepsis, and superior vena cava syndrome. Fifteen of 37 patients died, 13 of them during the hospitalization in which the thrombus was discovered. Thrombolytic agents and surgery were used to treat selected patients, with mixed results. Two of the 22 survivors have significant disability related to the thrombus or complications arising from it. We conclude that great vein and/or right atrial thrombosis is a common complication of central venous catheterization in small infants and children; moreover, the morbidity and mortality relating to this complication is substantial.

Calcified thrombus in the right atrium: a rare complication of long-term parenteral nutrition in a child

A 5-year-old boy with short-bowel syndrome who receives home parenteral nutrition developed a calcified thrombus that involved the inferior vena cava (IVC) and the right atrium. Symptoms included 3 to 4 months of intermittent fever and 2 months of vague chest pain. Blood could not be aspirated from the IVC catheter and an IVC contrast study demonstrated the calcified thrombus. The intracardiac portion of the mass was removed surgically, but the IVC mass could not be completely excised. The boy developed a pericardial effusion 6 weeks after surgery. He was treated for this and 6 months after the initial surgery the patient was asymptomatic.