Antibiotics for Aspiration Pneumonia in Neurologically Impaired Children
OBJECTIVE: To compare hospital outcomes associated with commonly used antibiotic therapies for aspiration pneumonia in children with neurologic impairment (NI).
DESIGN/METHODS: A retrospective study of children with NI hospitalized with aspiration pneumonia at 39 children’s hospitals in the Pediatric Health Information System database. Exposure was empiric antibiotic therapy classified by antimicrobial activity. Outcomes included acute respiratory failure, intensive care unit (ICU) transfer, and hospital length of stay (LOS). Multivariable regression evaluated associations between exposure and outcomes and adjusted for confounders, including medical complexity and acute illness severity.
RESULTS: In the adjusted analysis, children receiving Gram-negative coverage alone had two-fold greater odds of respiratory failure (odds ratio [OR] 2.15; 95% CI: 1.41-3.27), greater odds of ICU transfer (OR 1.80; 95% CI: 1.03-3.14), and longer LOS [adjusted rate ratio (RR) 1.28; 95% CI: 1.16-1.41] than those receiving anaerobic coverage alone. Children receiving anaerobic and Gram-negative coverage had higher odds of respiratory failure (OR 1.65; 95% CI: 1.19-2.28) than those receiving anaerobic coverage alone, but ICU transfer (OR 1.15; 95% CI: 0.73-1.80) and length of stay (RR 1.07; 95% CI: 0.98-1.16) did not statistically differ. For children receiving anaerobic, Gram-negative, and P. aeruginosa coverage, LOS was shorter (RR 0.83; 95% CI: 0.76-0.90) than those receiving anaerobic coverage alone; odds of respiratory failure and ICU transfer rates did not significantly differ.
CONCLUSIONS: Anaerobic therapy appears to be important in the treatment of aspiration pneumonia in children with NI. While Gram-negative coverage alone was associated with worse outcomes, its addition to anaerobic therapy may not yield improved outcomes.
© 2019 Society of Hospital Medicine
Neurologic impairment (NI) encompasses static and progressive diseases of the central and/or peripheral nervous systems that result in functional and intellectual impairments.1 While a variety of neurologic diseases are responsible for NI (eg, hypoxic-ischemic encephalopathy, muscular dystrophy), consequences of these diseases extend beyond neurologic manifestations.1 These children are at an increased risk for aspiration of oral and gastric contents given their common comorbidities of dysphagia, gastroesophageal reflux, impaired cough, and respiratory muscle weakness.2 While aspiration may manifest as a self-resolving pneumonitis, the presence of oral or enteric bacteria in aspirated material may result in the development of bacterial pneumonia. Children with NI hospitalized with aspiration pneumonia have higher complication rates, longer and costlier hospitalizations, and higher readmission rates when compared with children with nonaspiration pneumonia.3
While pediatric aspiration pneumonia is commonly attributed to anaerobic bacteria, this is largely based on extrapolation from epidemiologic studies that were conducted in past decades.4-8 A single randomized controlled trial found that penicillin and clindamycin, antimicrobials with similar antimicrobial activity against anaerobes, to be equally effective.9 However, the recent literature emphasizes the polymicrobial nature of aspiration pneumonia in adults, with the common isolation of Gram-negative enteric bacteria.10 Further, while Pseudomonas aeruginosa is often identified in respiratory cultures from children with NI and chronic respiratory insufficiency,11,12 the significance of P. aeruginosa in lower airways remains unclear.
We designed this study to compare hospital outcomes associated with the most commonly prescribed empiric antimicrobial therapies for aspiration pneumonia in children with NI.
MATERIALS AND METHODS
Study Design and Data Source
This multicenter, retrospective cohort study used the Pediatric Health Information System (PHIS) database. PHIS, an administrative database of 50 not-for-profit tertiary care pediatric hospitals, contains data regarding patient demographics, diagnoses and procedures, and daily billed resource utilization, including laboratory and imaging studies. Data quality and reliability are assured through the Children’s Hospital Association (CHA; Lenexa, Kansas) and participating hospitals. Due to incomplete data through the study period and data quality issues, six hospitals were excluded.
STUDY POPULATION
Inclusion Criteria
Children 1-18 years of age who were discharged between July 1, 2007 and June 30, 2015 were included if they had a NI diagnosis,1 a principal diagnosis indicative of aspiration pneumonia (507.x),3,13,14 and received antibiotics in the first two calendar days of admission. NI was determined using previously defined International Classification of Diseases, Ninth Revision-Clinical Modification (ICD-9-CM) diagnosis codes.1 We only included children who received antibiotics in the first two calendar days of admission to minimize the likelihood of including children admitted for other reasons who acquired aspiration pneumonia after hospitalization. For children with multiple hospitalizations, one admission was randomly selected for inclusion to minimize weighting results toward repeat visits.