Gram Negative Bacillary Nosocomial Bloodstream Infection (BSI) And Bronchopulmonary Dysplasia (BPD). † 1142

Abstract

Persistent GNB airway colonization is associated with severe BPD (Ped Inf Dis J 1997;16:18) but the contributing role of BSI to the latter is unclear. We examined these relationships using a cohort design. Data from 167 inborn infants (1991-96) who were intubated >2w included 691 tracheal (TA) and 434 blood cultures. BPD severity was assessed by duration of ventilation (VENT), O2 dependency at 36w GA and by the need for home O2 supplementation. Ten of 122 (8%) GNB airway colonized and 45 noncolonized infants developed nosocomial BSI. At the time of BSI, 21 infants had newly positive TA's, 13 had negative TA's and 11 (6 NEC) were nonintubated. BSI isolates from these patients were: P.aeruginosa (6),S.marcescens (3), K. pneumoniae (15), E. coli(21), E. cloacae (10). Eleven patients died (6 P. aeruginosa, 3 K. pneumoniae. 2 E. coli). Comparison between 31 positive TA (including 10 already colonized) and the remaining BSI infants were made. Demographics and perinatal factors were similar. Positive TA newborns were smaller, of younger GA, had greater mortality and more severe BPD. Four of the previously colonized and 6 of the new positive TA patients remained airway colonized to the time of death or extubation. All 167 infants with GNB in blood or TA represent 5% of admissions to the NICU during the study period. CONCLUSION: Prematures undergoing prolonged mechanical ventilation are at risk for GNB airway colonization, BSI, and nosocomial pneumonia. Eighty-two percent of nosocomial BSI's are not preceded by airway colonization. Infants who concurrently develop both positive TA and blood culture may be nosocomial pneumonia cases and at risk for significant mortality. GNB airway colonization is an independent and significant factor in clinically severe BPD. Table