Neonatal infectious pathology remains one of the main causes of morbidity and mortality in this age group. The introduction of plasticized catheters for the administration of medication, fluidotherapy and parenteral nutrition was a significant advance in treatment of patients at risk, but also led to the appearance of infectious complications. Negative coagulase staphylococcus is the principal pathogen in most neonatal intensive care units. Recent studies have examined the prophylactic use of vancomycin in preterm babies receiving parenteral nutrition. We have evaluated the efficacy of this procedure, applied via the central venous catheters employed for all neonates, within the intensive care unit over a period of one year. Prophylactic vancomycin administered via the catheters significantly reduced the incidence of Gram-positive infections, despite the presence within this group of a greater number of septic risk factors than in the control group.