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Pleural Effusion and Empyema 301

Because many of the infections that cause empyema are indolent,
a physician often sees patients after their empyema has already
reached the fibrino-purulent or organising stage. These patients often
are subjected to multiple surgical procedures and long hospital stays
before the empyema is successfully treated.
Thoracentesis, tube thoracostomy, intrapleural thrombolytics
(urokinase), thoracoscopic drainage, open drainage, and decortication
all have success rates ranging from 10 to 90%. 23,24 The variability in
the success rates of these procedures can be attributed, in part, to the
stage of the empyema at presentation. In the initial exudative stage,
an exudative effusion forms during the first 72 hours; this will usually
resolve as the pneumonia clears up following antibiotics therapy.
Antibiotic therapy and drainage of fluid collection are the mainstays
of treatment. Broad-spectrum intravenous antibiotic cover should be
commenced as soon as pus is aspirated from the chest and before culture
results are available. For a simple pleural effusion, aspiration of the
pleural space by thoracocentesis is usually adequate but may be repeated
as required. A malignant pleural effusion, such as that found in Kaposi
sarcoma, should be treated with repeated aspirations and chemotherapy.
The initial treatment of ET is medical. Appropriate antibiotic
Figure 46.3: Empyema with lung entrapment. selection should be based on the gram stain and culture of the pleural
fluid; however, because a large number of patients may have already
received antibiotics at the time of thoracentesis, an empiric selection
19
of the most appropriate antibiotics is necessary. The choice of
antibiotics should be based on the most common pathogens that cause
pneumonia within the patient’s age range and geographic location.
When the organism is identified, the antibiotics may be changed to
most specifically cover for the pathogen.
The duration of treatment is determined by the response to therapy;
a patient usually receives 10–14 days of intravenous antibiotics and
receives treatment until he or she responds appropriately to therapy,
with pyrexia reduced and supplemental oxygen no longer required.
Continuation of oral antibiotics may be recommended for 1–3 weeks
after discharge.
Surgical Management
Treatment of parapneumonic effusions aims to control the infection
and effect drainage of the pleural fluid to achieve full re-expansion of
the affected lung tissue 1,20 . Optimal treatments include antibiotics alone
(for small effusions or empyemas) or in combination with surgical
16
procedures. Numerous surgical options include thoracentesis, tube
15
thoracostomy, fibrinolytics, 7,13 thoracoscopy, 10,21,22 minithoracotomy,
16
open window drainage, or formal thoracotomy and decortication, 14, 22
Figure 46.4: Empyema with air fluid levels. which are described in the following sections.
Thoracentesis and Simple Tube Thoracostomy
mental settings and may prove to add prognostic value on the Thoracentesis or chest tube placements may be required to effect a
degree of inflammation present; these may be beneficial in deter- cure. In the second, fibrino-purulent stage, antibiotics with properly
mining treatment course in the near future. positioned chest tube drainage usually resolve the empyema thoracis.
Failures may be due to an improperly positioned tube, pleural locula-
• Where malignant effusion is suspected, cytological investigation
is mandatory. Rarely, a pleural biopsy may be indicated. tions, high fluid viscosity, or early peel on the lung. Failures are man-
aged with open drainage involving rib resection, decortications, intra-
• Pleural fluid latex agglutination (or counterimmunoelectrophore- pleural thrombolytics, or thoracoscopic drainage. Prompt drainage of
sis (CIE) for specific bacteria) may be helpful if the cause of the a free-flowing effusion prevents the development of loculations and a
infection cannot be ascertained from the usual culture results. fibrous peel. The tube is removed when the lung re-expands and drain-
Management age ceases. If the fluid is not free flowing, further radiologic imaging
is undertaken to better define the pleural space disorder.
There is contention regarding the management of empyema in children. In addition to the benefit of CT and ultrasonographic imaging to
The greatest discrepancies occur between nonsurgical and surgical spe- characterise loculated pleural effusions, the radiologist has become
cialists. The most controversial area in the management of empyema significantly involved in the treatment of empyema. The ability of
concerns which patients would benefit from pleural drainage and the the interventional radiologist to assist in the placement of small-bore
selection of the appropriate drainage intervention. For uncomplicated catheters, specifically localised to loculated pleural fluid collections,
free-flowing empyema, surgical intervention is rarely needed; however, has helped to facilitate drainage. Furthermore, with smaller-diameter
surgery is usually indicated for the multiloculated persistent empyema tubes, patients have tolerated tube placement better, with less associated
for which initial therapy may have been delayed or failed.
morbidity. In addition, radiologists can lyse adhesions directly by using