EXOGENOUS SURFACTANT DECREASES OXYGENATION IN ESCHERICHIA-COLI ENDOTOXIN-TREATED NEONATAL PIGLETS

Abnormalities of pulmonary surfactant function have been described in association with the acute respiratory distress syndrome (ARDS). Becau se gram-negative sepsis is a common cause of ARDS, we treated neonatal piglets with Escherichia coli endotoxin to create a neonatal ARDS mod el. We hypothesized that under these conditions administration of exog enous surfactant would improve pulmonary function. Study groups includ ed: control (n = 8), Exosurf(R) (5 mL/kg, 13.5 mg phospholipid/mL, n = 7), Survanta(R) (4 mL/kg, 25 mg phospholipid/mL, n = 6), and saline ( 5 mL/kg, n = 6). E. coli endotoxin 12 mu g/kg was infused over 30 min and resulted in significant pulmonary and hemodynamic abnormalities, h istopathologic evidence of nonhomogeneous lung injury, and elevated pr otein levels in bronchoalveolar lavage washings. Neither Exosurf(R) no r Survanta(R) ameliorated the pulmonary effects of endotoxin. Instead, there was a prolonged decrease in arterial oxygen tension (PaO2) and dynamic lung compliance after administration of surfactant and saline. Distribution of a bolus of Exosurf(R) was uneven throughout the lung. We conclude that in this neonatal piglet model of ARDS, bolus surfact ant administration had a detrimental effect on oxygenation and pulmona ry function. (C) 1996 Wiley-Liss, Inc.