Description of Respiratory Microbiology of Children With Long-Term Tracheostomies.

Background: There is little evidence in the medical literature to guide empiric treatment of pediatric patients with long-term tracheostomies who present with signs and symptoms of a bacterial respiratory infection. The overall goal of this study was to describe the respiratory microbiology in this study population at our institution.

Methods: This study was a retrospective chart review of all subjects with tracheostomies currently receiving care at the Arkansas Center for Respiratory Technology Dependent Children. Descriptive statistics were used to describe the respiratory microbiology of the full study group. Several subgroup analyses were conducted, including description of microbiology according to time with tracheostomy, mean time to isolation of specific organisms after the tracheostomy tube was placed, association between Pseudomonas aeruginosa or methicillin-resistant Staphylococcus aureus isolation and prescribed antibiotic courses, and description of microbiology according to level of chronic respiratory support. Available respiratory culture results up to July 2011 were collected for all eligible subjects. Descriptive statistics were used to describe subject characteristics, and chi-square analysis was used to analyze associations between categorical data. P < .05 was considered statistically significant.

Results: A total of 93 subjects met inclusion criteria for the study. The median (interquartile range) age at time of tracheotomy was 0.84 (0.36-3.25) y, and the median (interquartile range) time with tracheostomy was 4.29 (2.77-9.49) y. The most common organism isolated was P. aeruginosa (90.3%), with Gram-negative organisms predominating. However, 55.9% of the study population had a respiratory culture positive for methicillin-resistant S. aureus. The first organism isolated after tracheostomy placement was Methiciliin-sensitive S. aureus was isolated the soonest after tracheostomy placement. Specific organisms were not related to level of chronic respiratory support or likelihood of receiving antibiotics.

Conclusions: This study provides an updated overview of the variety of potential pathogens isolated from respiratory cultures of pediatric subjects with long-term tracheostomies.