AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

INTRODUCTION

Section 2 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Background

Bacterial pneumonia with associated pleural empyema is the most common cause of pleural effusion found in the pediatric population. Parapneumonic effusions are predominately exudative and occur in as many as 50-70% of patients admitted with a complicated pneumonia. The pulmonary infections of these patients extend into the pleural space and require more extensive therapy, with associated increased morbidity and extended hospital stay.

Involvement of the pleural space with pulmonary infections has been recognized since ancient times. Aristotle identified the increased morbidity and mortality associated with empyema and described drainage of empyema fluid with incision. The practice of surgical drainage as part of therapy for empyema has continued into the era of modern medicine. In his 1901 text, The Principles and Practice of Medicine, Sir William Osler, MD, stated that empyema should be treated as an ordinary abscess, "with incision and drainage." Of note, Osler underwent a rib resection for his own postpneumonic empyema, from which he ultimately expired.

Complicated parapneumonic effusions are appearing more frequently by most accounts, with reported increases in incidence rates in both in Europe and the United States. In England, the rate of admission with a diagnosis of empyema increased over the last decade, most notably in children aged 1-4 years. In addition, the identification of Streptococcus pneumoniae as the primary pathogen has also been reported, both in both the United States and abroad.

Pathophysiology

The definition of a parapneumonic effusion is a pleural effusion associated with either bacterial pneumonia or lung abscess or, rarely, external introduction of organisms associated with chest wall trauma. The development of parapneumonic effusions is gradual, with the pleural fluid collection most commonly divided into 3 stages. The progression of pleural fluid collection evolves from stage 1-3.

In stage 1, the exudative stage, the pleural inflammation from a contiguous infection results in increased permeability and a small fluid collection. At this stage, the effusion is thin and amenable to thoracentesis alone, contains mostly neutrophils, and is often sterile. Stage 2, the fibrinopurulent stage, is characterized by invasion of the organism into the pleural space, progressive inflammation and polymorphonuclear (PMN) leukocyte invasion, and the formation of fibrin membrane deposition, which forms partitions or loculations within the pleural space. Inflammation is characterized by progressive decreases in the pleural fluid glucose and pH and increased protein and lactate dehydrogenase (LDH). The last stage, stage 3, is the organizing stage, in which a pleural peel is created by the resorption of fluid and is associated with fibroblast proliferation that can result in parenchymal entrapment.

Empyema is defined by the presence of intrapleural pus and, for definition purposes, represents an advanced parapneumonic effusion. Complicated parapneumonic effusions (CPE) refer to those fluid collections that require tube thoracostomy or surgery for their resolution.

The accumulation of pleural effusions can rapidly occur in the presence of infection. The pleural surface is a mesothelial membrane that covers the lungs and chest wall. The resultant pleural space is a potential space, containing only small volumes of transudative fluid, with a protein content of less than 1.5 g/dL. This fluid is normally composed of lymphocytes, macrophages, and mesothelial cells, with an absence of neutrophils. Interaction of the mesothelium with the invading bacteria, PMNs, and resultant inflammatory mediators can increase pleural permeability. Further PMN recruitment ensues, which results in the increased production of neutrophil chemotactic mediators, ultimately leading to significant pleocytosis.

Activation of the coagulation cascade is common with pleural empyema. The pleural inflammatory response favors increased procoagulant activity, as well as depressed fibrinolytic activity, which favors fibrin deposition. Loculations result with these fibrin strands covered rapidly by a meshwork of fibroblasts that both proliferate and deposit basement membrane proteins onto the surface of the pleura. These proteins obscure the separation of the visceral and parietal pleura and lead to the formation of the pleural peel.

Following initiation of appropriate therapy, the inflammatory cellular and cytokine production recedes, and the PMN predominance of the parapneumonic effusion decreases. An influx of macrophages assists in the clearance of PMNs, with resolution of the inflammatory process. Migration of pleural mesothelial cells into areas of denuded mesothelium results in the reepithelialization of the pleura and recovery of normal function; however, following exuberant pleural inflammation, the potential for pleural fibrosis and restrictive lung disease is enhanced. The mechanisms that lead to either the development of pleural fibrosis or pleural repair with normal recovery are not well understood and need further investigation and characterization.

Frequency

United States

Parapneumonic effusions are predominately exudative and occur in as many as 50-70% of patients admitted with a complicated pneumonia. These patients have extension of their pulmonary infection into the pleural space and require more extensive therapy, with associated increased morbidity and extended hospital stay.

International

With an increased incidence of pneumonia and tuberculosis worldwide, the frequency of CPE is likely to be even higher.

Mortality/Morbidity

Early recognition of pneumonia with parapneumonic effusion, effective intervention to identify the infecting organism, and initiation of definitive therapy reduce the morbidity and complications associated with this process.

Age

The bacteriology of the infection varies with patient age. In the pediatric population, the most commonly implicated organisms are S pneumoniae, Staphylococcus aureus, and group A streptococci. The latter may be observed as a complication of an infectious skin disorder, such as varicella, impetigo, or infectious eczema. Haemophilus influenzae is rarely encountered since the advent of the H influenzae B vaccine.

CLINICAL

Section 3 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

History

• Clinical manifestations
• • Most patients with empyema present with clinical manifestations of bacterial pneumonia.
  • Their symptoms are characterized by an acute febrile response, pleuritic chest pain, cough, dyspnea, and, possibly, cyanosis.
  • The inflammation of the pleural space may cause abdominal pain and vomiting.
  • Patients frequently exhibit characteristic splinting of the affected side.
  • Symptoms may be blunted, and fever may not be present in patients who are immunocompromised.

Physical

Physical examination findings can vary as well.

• Auscultation reveals crackles, decreased breath sounds, and, possibly, a pleural rub, if the process is recognized before a large amount of fluid accumulates.
• Dullness to percussion and decreased breath sounds are likely but difficult to elicit in the younger child, who, because of discomfort, may be less cooperative with the examination.
• Physical findings and presentation may vary depending on the organism and the duration of the illness.

Causes

• Increased pleural permeability associated with pneumonia or lung abscesses, as well as contiguous infections of the esophagus, mediastinum, or subdiaphragmatic region, may extend to involve the pleura.
• Similarly, retropharyngeal, retroperitoneal, or paravertebral processes may extend to adjacent structures and involve the pleura, as well.
• Host factors that contribute to alterations in pleural permeability, such as noninfectious inflammatory diseases, infection, trauma, or malignancy, may allow accumulation of fluid in the pleural space, which becomes secondarily infected.
• The bacteriology of the pleural space varies with patient age. In the pediatric population, the most common implicated organisms are S pneumoniae, S aureus, and group A streptococci. H influenzae is rarely observed since the advent of the H influenzae B vaccine.
• Because of the use of oral antibiotics before the recognition of the parapneumonic effusion, most specimens cultured are sterile; thus, the relative incidences of the aforementioned organisms are not known.
• Anaerobic infections secondary to aspiration and fungal or mycobacterial infections in immunosuppressed patients are also reported.
• Finally, Mycoplasma pneumoniae and viruses can rarely result in exudative pleural effusions, although mononuclear cells primarily characterize them.

DIFFERENTIALS

Section 4 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Other Problems to be Considered

The differential diagnosis of bacterial empyema is best considered by examining the anatomy and physiology of the pleural space.

WORKUP

Section 5 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Lab Studies

• CBC count
• Blood culture: Blood culture is obtained to assist in the identification of the offending organism. In pediatric patients, where sputum production is uncommon, identifying the cause of the pulmonary symptoms early in the course of a pulmonary infection is difficult. However, with parapneumonic effusions, the patient may become bacteremic as the organism invades into the pleural space, and a blood culture may reveal the organism.
• Serum LDH level
• Total protein
• Glucose concentration
• Bacterial, mycobacterial, and fungal cultures
• Serologic studies of the aspirated pleural fluid
• pH level
• Amylase concentration
• Lipid stain or triglycerides
• Cell count and differential: Although the pleural fluid obtained at thoracentesis is typically purulent, with an elevated WBC count and a predominance of PMNs, an effusion evaluated early in the infectious process may well be more transudative, with a less cellular WBC count and a differential that is less PMN predominant. Regardless of the cell count and differential, the treatment should be based on clinical course, pending the culture results. Cytokine analyses of pleural fluid have been performed in experimental settings and may prove to add prognostic value on the degree of inflammation present and may be beneficial in determining treatment course in the near future.

Imaging Studies

• Diagnostic evaluation
• • Radiologic evaluation is the primary tool for the diagnosis of a parapneumonic effusion. Standard chest radiography is the first step to assess for pleural fluid.
  • Examination should include upright views of the chest to examine the diaphragmatic margins, which are obliterated with pleural fluid collections. Because up to 400 mL may be required before these costophrenic angles are obscured in older children and adolescents, further diagnostic imaging may be needed.
  • In cases in which the effusion is moderate, the radiograph may demonstrate displacement of the mediastinum to the contralateral hemithorax, as well as scoliosis.
  • Indistinct diaphragmatic contours merit lateral decubitus views of the chest.
  • Free-flowing pleural effusions suggest less complicated parapneumonic processes, which may not require extensive diagnostic and therapeutic interventions. The absence of free layering on the decubitus films does not exclude the possibility of a loculated pleural effusion.
  • Consider sonography or CT imaging to identify the presence of consolidated lung or fibrinous septations. In patients with complex fluid collections, chest CT imaging has emerged as the study of choice. Chest CT imaging can be used to detect and define pleural fluid and image the airways, guide interventional procedures, and discriminate between pleural fluid and chest consolidation.

Other Tests

• Pleural fluid latex agglutination (or counter immunoelectrophoresis [CIE] for specific bacteria) may be helpful if the cause of the infection cannot be ascertained from culture results.

Procedures

• Thoracentesis can provide both significant diagnostic information and therapeutic relief for parapneumonic effusions.
• • The presence of pus establishes the presence of an empyema, and the determination of the Gram stain, cell differential, and chemistries helps to guide therapy.
  • Performing thoracentesis before the initiation of antibiotics increases the diagnostic yield of the fluid cultures and allows for more specific antimicrobial therapy.

TREATMENT

Section 6 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Medical Care

Treatment of parapneumonic effusions should address control of the infection and often involves drainage of the pleural fluid and reexpansion of the affected lung tissue.

• Appropriate antibiotic 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 of the most appropriate antibiotics is necessary.
• • Base the choice on the most common pathogens that cause pneumonia within the patient's age range and geographic location.
  • When the organism is identified, change the antibiotics to most specifically cover for the pathogen.
  • Patients with empyema should receive a longer course of therapy analogous to necrotizing pneumonia, but the response to therapy determines the duration of treatment. The patient receives 10-14 days of intravenous antibiotics and receives treatment until he or she is afebrile, off supplemental oxygen, and appropriately responds to therapy.
  • Continuation of oral antibiotics may be recommended for 1-3 weeks after discharge but is not required for less complicated infections.
• The most controversial area in the management of parapneumonic effusions is the identification of patients who would benefit from pleural drainage and the selection of the appropriate drainage intervention.
• • No clinical studies have effectively contrasted antibiotic treatment without drainage to currently available drainage techniques. However, long-term follow-up studies show no differences in pulmonary function or exercise capacity between the groups. The therapeutic discussion rests on available clinical, radiologic, and laboratory evidence; host factors; and individualization to make the appropriate decision.
  • The pulmonologist, intensivist, interventional radiologist, or surgeon can perform simple tube thoracostomy with an underwater seal.
  • Diagnostic thoracentesis and chest tube drainage are effective therapies in more than 50% of patients. Prompt drainage of a free-flowing effusion prevents the development of loculations and a fibrous peel.
  • Remove the tube when the lung re-expands and drainage ceases. If the fluid is not free flowing, undertake further radiologic imaging to better define the pleural space disorder.
• In addition to the benefit of CT and ultrasonographic imaging to characterize loculated pleural effusions, the radiologist has become significantly involved in the treatment of CPE.
  • The ability of the interventional radiologist to assist in the placement of small-bore catheters, specifically localized to loculated pleural fluid collections, has helped to facilitate drainage. Furthermore, with smaller diameter tubes, patients have tolerated tube placement better, with less associated morbidity.
  • In addition, radiologists can lyse adhesions directly using imaging during the tube placement.
  • Finally, interventional radiologists, using fibrinolytics, have further improved the care of the complicated empyema by improved management of loculations and amelioration of fibrous peel formation and fibrin deposition.
• Numerous studies have documented the effectiveness of intrapleural fibrinolytics to treat obstructed thoracostomy tubes, increase drainage in multiloculated effusions, and to lyse adhesions; however, initial studies report on the use of urokinase, the fibrinolytic most commonly described prior to 1998, evolving to the use of tissue plasminogen activator (TPA), which has become the most frequently used treatment. Cost may limit its more widespread use. Randomized trials of chest tube drainage with fibrinolytics versus simple drainage and surgical therapy need to be undertaken to fully assess the relative clinical value of fibrinolytic therapy.

Surgical Care

Controversy continues regarding the surgical treatment of CPE.

• For the uncomplicated free-flowing parapneumonic effusion, surgical intervention is rarely needed; however, the multiloculated persistently symptomatic effusion, for which initial therapy may have been delayed, is likely to require more than conservative management.
• The surgical literature supports the use of thoracotomy to remove the pleural peel and lyse the adhesions, if the patient does not respond promptly to treatment. Length of stay and long-term morbidity are reduced by this more aggressive approach, but this must be contrasted with the increased cost and short-term morbidity associated with thoracotomy and decortication. This treatment regimen is very effective, with a reported 95% success rate for patients with fibrinopurulent effusions. Because no prospective comparative studies have contrasted the current techniques, decortication is likely to remain a treatment of choice for advanced empyema.
• Video-assisted thoracoscopic surgery (VATS) has proven to be an effective and less-invasive replacement for the limited decortication procedure. Thoracoscopic debridement closely imitates open thoracotomy and drainage. Mechanical removal of purulent material and the breakdown of adhesions can be easily accomplished via this route. VATS results in more rapid relief of symptoms, earlier hospital discharge, and significantly less discomfort and morbidity.
• Despite the benefits, a small percentage of patients still progress to require thoracotomy. As with fibrinolytic therapy, those patients in which this therapy has been most effective are those slightly less affected in whom earlier and potentially more aggressive treatment has been initiated.
• The definitive approach is thoracotomy drainage with mechanical release of the pleural peel and lysis of adhesions. Studies of decortication and debridement report 95% effectiveness for empyemas in the fibrinopurulent stage. These outcomes are determined by selected clinical outcomes, such as resolution of symptoms; however, these studies are subject to selection bias and do not account for the morbidity associated with the procedure, as well as increased costs associated with an operative procedure and the associated anesthesia risk. Furthermore, most children heal well in the long run, even without immediate surgical intervention.
• A recent meta-analysis reviewed the differences between primary operative treatment with nonoperative management and revealed striking reductions in length of stay, duration of tube thoracostomy, and duration of antibiotics. However, these data are susceptible to critics who point out the same concerns regarding selection biases that have been listed above. An additional review of surgical options demonstrated that early VATS resulted in shortening hospitalization times, but other outcomes such as duration of symptoms or antibiotic use were less dramatic between surgical treatments. In conclusion, early intervention of any sort is likely to improve outcomes, but early VATS is the surgical approach now most preferred in managing children with empyema.
• Alternative procedures, such as rib resection and open drainage or pleural obliteration, are rarely needed in the pediatric population.
• To most effectively determine the optimal therapeutic intervention, a carefully designed, multicentered, randomized, clinical trial would help to develop evidence-based standards for the treatment of complicated parapneumonic effusion in children.

Consultations

Consultants may include pediatric surgeons (thoracic or general), interventional radiologists, intensivists, and pulmonologists.

Activity

Patients should perform as much activity as can be tolerated.

• Encourage the facilitation of deep breathing and airway clearance.
• Use analgesics on an individual basis to facilitate airway clearance.

MEDICATION

Section 7 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Individualize IV antibiotics by both age and likelihood of the offending organism. In the case of a possible aspiration, such as in the patient who is debilitated or neurologically impaired, consider coverage for anaerobic infection.

Drug Category: Antibiotics

These agents are recommended for the most likely bacterial infections; the specific agent selected should be individualized based on the offending organism. They may include, but are not limited to, the following:

Drug Category: Antibiotics, anaerobic infections

In situations in which an aspiration or likely anaerobic infection is the cause of the pneumonia, coverage for anaerobes is recommended.

Drug Category: Thrombolytic agents

These agents convert plasminogen to plasmin, leading to clot lysis. These agents are used to lyse adhesions in the pleural space.

FOLLOW-UP

Section 8 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Further Outpatient Care

• Obtain follow-up radiographs and pulmonary function tests to determine prognosis and to confirm resolution of pleural and parenchymal changes.
• Consider a follow-up chest CT scan after the radiograph clears.

In/Out Patient Meds

• See Medication.

Transfer

• Children should receive their care in hospitals equipped to deal with ill children and staffed with the appropriate pediatric subspecialists.

Complications

• Fibrothorax, a complication reported in the adult literature, is rarely observed in pediatric patients.

Prognosis

• The prognosis for most patients with parapneumonic effusions is quite good.
• Extended antibiotics may be needed in some patients with CPE.
• Despite the variability in presentation, most patients recover without sequelae.
• A number of studies have demonstrated resolution of the radiographic abnormalities by 3-6 months following therapy, with few to no symptoms reported at follow-up examination.
• Pulmonary function testing performed following hospitalization has not shown marked abnormalities, regardless of clinical course. The only abnormality observed may be slight expiratory flow limitation. Mild obstructive abnormalities were the only findings observed in patients evaluated 12 years (± 5) following recovery from empyema.
• Some increased bronchial reactivity has been reported at later follow-up examinations; however, lung function and exercise response return to normal for most patients.
• Early recognition of pneumonia with parapneumonic effusion, effective intervention to identify the causative organism, and initiation of definitive therapy reduce morbidity and complications associated with this process.

Patient Education

• For excellent patient education resources, visit eMedicine's Pneumonia Center. Also, see eMedicine's patient education article Bacterial Pneumonia.

MISCELLANEOUS

Section 9 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Medical/Legal Pitfalls

• Early recognition and appropriate intervention with the listed transfer or consultation and the institution of appropriate drainage and intravenous antibiotics with aforementioned monitoring should lead to a good clinical response and decrease the risk of litigation.

MULTIMEDIA

Section 10 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Media file 1:  Radiographic imaging of a parapneumonic effusion may be useful in assessing the stage of the effusion and the type of drainage needed. In Figure A, the left heart border is obscured, and greater than 50% of the left hemithorax is filled with an effusion, as evidenced by a fluid meniscus. In Figure B, the effusion is demonstrated to be fluid because it layers out on a decubitus film. In Figure C, the lateral radiograph again demonstrates the fluid meniscus and filling of the posterior sulcus. These findings suggest tube thoracostomy placement may be sufficient to drain this pleural process.
	View Full Size Image
Media type:  X-RAY

Media file 2:  Most parapneumonic effusions treated with the appropriate antimicrobials of sufficient duration resolve without the development of complications or sequelae. The series of radiographs represent a patient treated with thoracentesis alone. Figure A illustrates the patient at presentation. Note the amount of fluid present. In Figure B, the radiograph demonstrates progression of the pleural fluid accumulation with further airspace disease and scoliosis noted. Despite the radiographic evidence of disease progression, the patient was clinically improving. Figure C illustrates the radiograph at follow-up, 6 months following completion of therapy. Resolution of the parapneumonic effusion with no evidence of pleural thickening or fibrosis occurred.
	View Full Size Image
Media type:  X-RAY

REFERENCES

Section 11 of 11

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

• Alkrinawi S, Chernick V. Pleural infection in children. Semin Respir Infect. Sep 1996;11(3):148-54. [Medline].
• Antony VB, Mohammed KA. Pathophysiology of pleural space infections. Semin Respir Infect. Mar 1999;14(1):9-17. [Medline].
• Avansino JR, Goldman B, Sawin RS, Flum DR. Primary operative versus nonoperative therapy for pediatric empyema: a meta-analysis. Pediatrics. Jun 2005;115(6):1652-9. [Medline].
• Bouros D, Schiza S, Siafakas N. Fibrinolytics in the treatment of parapneumonic effusions. Monaldi Arch Chest Dis. Jun 1999;54(3):258-63. [Medline].
• Bouros D, Schiza S, Tzanakis N, et al. Intrapleural urokinase versus normal saline in the treatment of complicated parapneumonic effusions and empyema. A randomized, double-blind study. Am J Respir Crit Care Med. Jan 1999;159(1):37-42. [Medline].
• Brook I. Lung abscesses and pleural empyema in children. Adv Pediatr Infect Dis. 1993;8:159-76. [Medline].
• Bryant RE, Salmon CJ. Pleural empyema. Clin Infect Dis. May 1996;22(5):747-62; quiz 763-4. [Medline].
• Gates RL, Caniano DA, Hayes JR, Arca MJ. Does VATS provide optimal treatment of empyema in children? A systematic review. J Pediatr Surg. Mar 2004;39(3):381-6. [Medline].
• Givan DC, Eigen H. Common pleural effusions in children. Clin Chest Med. Jun 1998;19(2):363-71. [Medline].
• Grewal H, Jackson RJ, Wagner CW, Smith SD. Early video-assisted thoracic surgery in the management of empyema. Pediatrics. May 1999;103(5):e63. [Medline].
• Hardie WD, Roberts NE, Reising SF, Christie CD. Complicated parapneumonic effusions in children caused by penicillin-nonsusceptible Streptococcus pneumoniae. Pediatrics. Mar 1998;101(3 Pt 1):388-92. [Medline].
• Heffner JE, McDonald J, Barbieri C, Klein J. Management of parapneumonic effusions. An analysis of physician practice patterns. Arch Surg. Apr 1995;130(4):433-8. [Medline].
• Heffner JE. Infection of the pleural space. Clin Chest Med. Sep 1999;20(3):607-22. [Medline].
• Heffner JE. Indications for draining a parapneumonic effusion: an evidence-based approach. Semin Respir Infect. Mar 1999;14(1):48-58. [Medline].
• Hoff SJ, Neblett WW, Edwards KM, et al. Parapneumonic empyema in children: decortication hastens recovery in patients with severe pleural infections. Pediatr Infect Dis J. Mar 1991;10(3):194-9. [Medline].
• Hoff SJ, Neblett WW 3rd, Heller RM, et al. Postpneumonic empyema in childhood: selecting appropriate therapy. J Pediatr Surg. Jul 1989;24(7):659-63; discussion 663-4. [Medline].
• Kennedy AS, Agness M, Bailey L, White JJ. Decortication for childhood empyema. The primary provider's peccadillo. Arch Surg. Oct 1991;126(10):1287-91. [Medline].
• Kern JA, Rodgers BM. Thoracoscopy in the management of empyema in children. J Pediatr Surg. Sep 1993;28(9):1128-32. [Medline].
• Kosloske AM, Cartwright KC. The controversial role of decortication in the management of pediatric empyema. J Thorac Cardiovasc Surg. Jul 1988;96(1):166-70. [Medline].
• LeMense GP, Strange C, Sahn SA. Empyema thoracis. Therapeutic management and outcome. Chest. Jun 1995;107(6):1532-7. [Medline].
• Light RW. Pleural effusion. In: Nadel JA, ed. Textbook of Respiratory Medicine. 2nd ed. Philadelphia, Pa:. WB Saunders;1994: 1719-30.
• McLaughlin FJ, Goldmann DA, Rosenbaum DM, et al. Empyema in children: clinical course and long-term follow-up. Pediatrics. May 1984;73(5):587-93. [Medline].
• Moulton JS, Benkert RE, Weisiger KH, Chambers JA. Treatment of complicated pleural fluid collections with image-guided drainage and intracavitary urokinase. Chest. Nov 1995;108(5):1252-9. [Medline].
• Osler W. The Principles and Practice of Medicine. 4th ed. New York, NY:. D Appleton;1901:108.
• Pollak JS, Passik CS. Intrapleural urokinase in the treatment of loculated pleural effusions. Chest. Mar 1994;105(3):868-73. [Medline].
• Ramnath RR, Heller RM, Ben-Ami T, et al. Implications of early sonographic evaluation of parapneumonic effusions in children with pneumonia. Pediatrics. Jan 1998;101(1 Pt 1):68-71. [Medline].
• Redding GJ, Walund L, Walund D, et al. Lung function in children following empyema. Am J Dis Child. Dec 1990;144(12):1337-42. [Medline].
• Sahn SA. Management of complicated parapneumonic effusions. Am Rev Respir Dis. Sep 1993;148(3):813-17. [Medline].
• Stovroff M, Teague G, Heiss KF, et al. Thoracoscopy in the management of pediatric empyema. J Pediatr Surg. Aug 1995;30(8):1211-5. [Medline].
• Stringel G, Hartman AR. Intrapleural instillation of urokinase in the treatment of loculated pleural effusions in children. J Pediatr Surg. Dec 1994;29(12):1539-40. [Medline].
• Wells RG, Havens PL. Intrapleural fibrinolysis for parapneumonic effusion and empyema in children. Radiology. Aug 2003;228(2):370-8. [Medline].

Article Last Updated: Jan 2, 2007