Plasma prostanoids in neonates with pulmonary hypertension treated with conventional therapy and with extracorporeal membrane oxygenation.

Thromboxane may be a mediator of pulmonary hypertension in the neonate. Acute thromboxane-mediated pulmonary hypertension has been described in sheep receiving extracorporeal membrane oxygenation, which raises concerns about a potential thromboxane-mediated exacerbation of pulmonary hypertension in human neonates with severe pulmonary hypertension who are treated with extracorporeal membrane oxygenation. We measured plasma levels of thromboxane, prostaglandin F2 alpha, and 6-keto-prostaglandin F1 alpha in infants with pulmonary hypertension, some of whom were treated medically and some of whom were treated with extracorporeal membrane oxygenation. Plasma levels of all three prostanoids were elevated in infants with pulmonary hypertension and decreased with time, whether the neonates were treated with extracorporeal membrane oxygenation or with medical management alone. In infants treated with extracorporeal membrane oxygenation, we collected samples simultaneously from preoxygenator sites, postoxygenator sites, and umbilical artery catheter. We could demonstrate no significant difference in plasma prostanoid levels across the oxygenator. In two patients, plasma thromboxane and prostaglandin F2 alpha levels measured shortly after a platelet transfusion were distinctly higher in the umbilical artery catheter than in venous samples.