(Courtesy of George W. Holcomb, MD)
Figure 3. Tenacious exudate in the intrapleural space at the time of VATS in a child with empyema.
Management: Antibiotics and the Role of Pleural Drainage Procedures
Figure 2 on page 58 shows an algorithm that guides clinical management of the empyema patient. Once a diagnosis is made, attention should be directed to fluid and electrolyte correction, hemodynamic stabilization, and respiratory support (i.e., oxygenation and ventilation). Antibiotics should be initiated and the choice is based on severity of illness and age of the child.
Drainage of the pleural pus has long been recognized as integral to the success in treatment of pneumonia with empyema. Recently, there has been much debate concerning which modality to use and when.
Intrapleural fibrinolytic therapy has been shown in multiple studies to decrease length of stay without increased risk. Data compiled in the Cochrane database comparing fibrinolytic therapy vs. more conservative management suggests that intrapleural fibrinolytic therapy confers significant benefit when compared with normal saline control; however, a definitive statement was not made, given that the trial numbers were too small (11). More recent data from the Cochrane database and a systematic review suggest that video-assisted thoracostomy (VATS) performed early in the disease course is associated with better outcome than chest tube drainage with streptokinase with regard to duration of chest tube placement and hospital stay. However there are questions about validity, and this study is also too small to draw conclusions (12,13). Figure 3 shows the typical findings encountered at VATS in a child with empyema.
A retrospective chart review from our institution from December 2000 to March 2004, excluding immunocompromised hosts, found 96 cases of radiographic pneumonia with pleural effusion. Thirty-four met criteria for empyema, including ultrasound and/or chest CT showing pleural fluid loculation and septation, or purulent fluid/positive culture. Average age was 5 years, and pathogens were defined in 38% of patients. Length of stay averaged 9 days, with a range of 5–23 days. Two had no intervention and had a stay of 8 days, 14 had tube thoracostomy and had an average stay of 11.5 days with 6 failures, 10 had thoracostomy and fibrinolytic therapy with an average stay of 7 days, 3 had early VATS with an average stay of 7 days, and 5 had late VATS with an average stay of 10.4 days. In our institution, among invasive interventions, tube thoracostomy alone had longer LOS and more failures. Early VATS and intrapleural fibrinolysis have shorter stays and are on the lower end of the cost scale: $25,549 vs. $21,062 respectively (Figure 4).
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The decision for interventional management of empyema will likely be institutionally variable in the absence of large randomized controlled studies. Institutions with aggressive interventional radiologists may favor thoracostomy tube with fibrinolysis. Those with surgeons skilled in video-scopic surgery may provide early VATS. Data on interventions clearly show benefit beyond that provided by routine chest tube placement. The key becomes prompt diagnosis of empyema with early use of ultrasound, knowledge of local antibiotic susceptibilities, and clear guidelines set up by each institution to guide interventional management.
The Future
Increasing the accuracy of diagnostic testing for children with CAP would likely lead to decreased morbidity, mortality, and total cost of care. The use of PCR is becoming more widespread and could be utilized to more rapidly confirm the diagnosis of both chlamydophila pneumoniae, mycoplasma pneumoniae, and Influenza A virus (14). Influenza A is well known to cause serious morbidity and mortality and may be the most common virus causing CAP, with a comparable clinical burden to viruses such as respiratory syneytial virus. This is further evidence supporting universal childhood influenza immunization. Expansion of the serotypes included in pneumococcal conjugate vaccines (PCV) is to include serotypes 1 and 3, both currently non-PCV strains in the U.S. vaccine, is underway.