Rejection criteria for endotracheal aspirates in neonates. Clinical impact

It has been suggested that endotracheal suction specimens from adult and pediatric patients be rejected for culture if no organisms are seen on Gram's stain. We reviewed the experience in neonates under three months of age from our neonatal intensive care unit. Of 195 such endotracheal specimens, 86 (44%) had no growth by culture, 83 (43%) grew normal flora only, and 26 (13%) from 22 patients grew a potential pathogen. Detailed chart review was undertaken to determine what the clinical outcome would have been if the culture information were not provided for these patients. Based on this analysis, almost all patients with Gram-negative rods would have empirically received antibiotics on clinical grounds regardless of culture results, and at least one received antibiotics unnecessarily based on a culture result. On the other hand, two patients whose cultures grew Trichosporon and Aspergillus would have been missed.