Are some children with empyema at risk for treatment failure with fibrinolytics? A multicenter cohort study.

Background: Guidelines recommend that children with empyema be treated initially with chest tube insertion and intrapleural fibrinolytics. Some patients have poor outcomes with this approach, and it is unclear which factors are associated with treatment failure.

Methods: Possible risk factors were identified through a review of the literature. Treatment failure was defined as need for repeat pleural drainage and/or total length of stay greater than 2weeks.

Results: We retrospectively identified 314 children with empyema treated with fibrinolytics at The Hospital for Sick Children (2000-2013, n=195), Children's Hospital, London Health Sciences Centre (2009-2013, n=39), and McMaster Children's Hospital (2007-2014, n=80). Median length of stay was 11days (range 5-69days). Thirteen percent of children required repeat drainage procedures, and 34% experienced treatment failure. There were no deaths. White blood cell count, erythrocyte sedimentation rate, C-reactive protein, albumin, urea to creatinine ratio, and signs of necrosis on initial chest x-ray were not associated with treatment failure. Multivariable logistic regression demonstrated increased risk with positive blood culture (odds ratio=2.7), immediate admission to intensive care (odds ratio=2.6), and absence of complex septations on baseline ultrasound (odds ratio=2.1). Male gender and platelet count were associated with treatment failure in the univariate analysis but not in the multivariable model.

Conclusions: Predicting which children with empyema are at risk for treatment failure with fibrinolytics remains challenging. Risk factors include positive blood culture, immediate admission to intensive care, and absence of complex septations on ultrasound. Routine blood work and inflammatory markers have little prognostic value.