Although the pulmonary circulation in infants with advanced bronchopulmonary dysplasia (BPD) is characterized by abnormal structure and vasoreactivity, metabolic lung functions have not been studied ...in these infants. To test the hypothesis that patients with severe BPD may have abnormal metabolic lung function, we assessed the pulmonary vascular extraction of circulating norepinephrine in six children with BPD during cardiac catheterization. Plasma norepinephrine levels were measured from simultaneously drawn mixed venous (main pulmonary artery) and left atrium or femoral artery samples. In comparison with four infants with mild heart disease without pulmonary hypertension, we found that infants with BPD extract proportionately less norepinephrine than non-BPD infants -7 +/- 50% (BPD) versus +27 +/- 6% (non-BPD); P less than 0.001, t test. Three infants with BPD had higher arterial than mixed venous concentrations of plasma norepinephrine, suggesting net production across the lung. Plasma catecholamine levels and percent extraction correlated poorly with cardiac index and systemic and pulmonary vascular resistance indices. However, this study group was characterized by a high incidence of pulmonary (6/6) and systemic (4/6) hypertension, left ventricular hypertrophy (4/6), and subsequent death (3/6). We conclude that infants with severe BPD and pulmonary hypertension have decreased pulmonary vascular clearance or net production of circulating norepinephrine, but links between altered pulmonary catecholamine metabolism and pulmonary hypertension, or other cardiovascular abnormalities associated with BPD, remain speculative.
We present a case of homozygous protein C deficiency with neonatal purpura fulminans and disseminated intravascular coagulopathy (DIC) starting shortly after birth. In addition, the infant had ...vitreal eye hemorrhages and intraparenchymal brain infarction, apparently as intrauterine events. Within 15 hours of institution of fresh frozen plasma (FFP) infusions the DIC resolved and the progression of purpura fulminans reversed. Warfarin (0.4 mg/kg/day) was started on the fifth day of life, followed by gradual tapering of the FFP infusions. There were no recurrences of purpura, areas of skin necrosis healed without the need for skin grafting, and the areas of brain infarction resolved without apparent sequelae. The eye and brain lesions may be intrauterine events and appear to be a regular feature of this syndrome. Family studies are essential to establish the diagnosis, although there may be no family history of thromboembolic events, as in this case. Homozygous protein C deficiency is a rare disorder, but one in which early recognition and intervention may be lifesaving. Ours is the youngest patient yet reported to be treated with warfarin anticoagulation. We were thus able to avoid the complications of long-term plasma therapy as well as the potential thrombotic complications of central venous catheter placement.
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