Pleural Effusions Internal Medicine AM Report Andrew Smitherman Wednesday May 27, 2009

Definition Excess fluid in space between the lung and chest wall. Excess fluid in space between the lung and chest wall.

Pathophysiology Fluid typically enters pleural space from capillaries in the parietal pleura, from the pulmonary interstitium via visceral pleura or from peritoneal cavity via small holes in the diaphragm. Fluid typically enters pleural space from capillaries in the parietal pleura, from the pulmonary interstitium via visceral pleura or from peritoneal cavity via small holes in the diaphragm. Lymphatics are able to increase absorption 20 times that of normal if needed. Lymphatics are able to increase absorption 20 times that of normal if needed. An effusion forms when the production of pleural fluid overwhelms the ability of the lymphatics to drain or due to decreased lymphatic drainage. An effusion forms when the production of pleural fluid overwhelms the ability of the lymphatics to drain or due to decreased lymphatic drainage.

Etiologies CAUSE ANNUAL INCIDENCE TRANSUDATE / EXUDATE? CHF500,000Transudate Pneumonia300,000Exudate Malignancy200,000Exudate Pulmonary Embolus 150,000Either Viral Disease 100,000Exudate Post CABG 60,000Exudate Cirrhosis with Ascities 50,000Transudate Light, RW. Pleural Effusion. NEJM. 2002; 246:

Etiologies TransudateExudate Congestive Heart Failure Malignancy – Metastatic or Mesothelioma Cirrhosis Infection / Parapneumonic / Empyema Pulmonary Embolus Nephrotic Syndrome GI Disease – Pancreatic Disease, Esophageal Perforation, Intraabdominal Abscess, After Abdominal Surgery SVC Obstruction Collagen-Vascular Disease – SLE, Rheumatoid Pleuritis, Wegner’s, Sjögrens Peritoneal Dialysis Post CABG UrinothoraxSarcoidosis Uremia Drug-Induced – Nitrofurantoin, Amiodarone Meig’s Radiation Therapy

Initial Evaluation with Physical Exam Typical findings: Dullness to percussion, absence of tactile fremitus Diminished or absence of breath sounds Findings suggestive of a particular etiology: S 3, Distended Neck Veins, Peripheral Edema – CHF RV Heave or Thrombophlebitis – Pulmonary Embolism Lymphadenopathy or Hepatosplenomegaly – Malignancy Ascities – Hepatic Failure / Cirrhosis

What’s My Claim to Fame? Josef Leopold Auenbrugger (1722 – 1809)

What’s My Claim to Fame? Josef Leopold Auenbrugger (1722 – 1809) Developed physical exam techniques of chest percussion and tactile fremitus

Indications for Thoracentesis Diagnostic: effusion > 10mm in height on lateral decubitus or ultrasonography Diagnostic: effusion > 10mm in height on lateral decubitus or ultrasonography Therapeutic: patient symptomatic – dyspnea at rest, increased O2 requirement. Removal of up to 1500mL indicated. Therapeutic: patient symptomatic – dyspnea at rest, increased O2 requirement. Removal of up to 1500mL indicated. If patient presents with likely CHF exacerbation, with bilateral effusions, afebrile and reports no chest pain a trial of diuresis is reasonable and safe. If patient presents with likely CHF exacerbation, with bilateral effusions, afebrile and reports no chest pain a trial of diuresis is reasonable and safe. Greater than 80% of effusions due to CHF are bilateral Greater than 80% of effusions due to CHF are bilateral 75% of effusions due to CHF resolve in 48 hours of diuresis 75% of effusions due to CHF resolve in 48 hours of diuresis If effusions persist for >72hrs a thoracentesis is indicated If effusions persist for >72hrs a thoracentesis is indicated Unilateral or Asymmetric effusions should be tapped Unilateral or Asymmetric effusions should be tapped Shinto RA and Light RW. Effects of Diuresis on the Characteristics of Pleural Fluid in Patients with Congestive Heart Failure. American Journal of Medicine. 1990; 88:

Do I Need a Follow-up Chest Radiograph? Not needed unless air is obtained during procedure; coughing, chest pain or dyspnea develops; or tactile fremitus is lost over apex of aspirated hemithorax. Not needed unless air is obtained during procedure; coughing, chest pain or dyspnea develops; or tactile fremitus is lost over apex of aspirated hemithorax. Of 506 thoracenteses, pneumothorax found in 13 of 18 (72%) with one or more of the above findings but only in 5 of 488 (1%) with none of the above. Of 506 thoracenteses, pneumothorax found in 13 of 18 (72%) with one or more of the above findings but only in 5 of 488 (1%) with none of the above. Aleman C, Alegre J, Armadans L. The Value of the Chest Roentgenography in the Diagnosis of Pneumothorax After Thoracentesis. American Journal of Medicine. 1999; 107:

Transudate v. Exudate Transudate: usually due to systemic changes and an imbalance between hydrostatic and oncotic forces. Transudate: usually due to systemic changes and an imbalance between hydrostatic and oncotic forces. CHF, Cirrhosis, Pulmonary Embolism CHF, Cirrhosis, Pulmonary Embolism Exudate: due to local changes that lead to fluid accumulation. Exudate: due to local changes that lead to fluid accumulation. Pneumonia, Malignancy, Pulmonary Embolism Pneumonia, Malignancy, Pulmonary Embolism

Transudate v. Exudate

By the Light’s Criteria alone, 17 of 100 samples tested will falsely be categorized as an exudate. By the Light’s Criteria alone, 17 of 100 samples tested will falsely be categorized as an exudate. If you have a clinical situation where transudate seems more plausible, compare pleural fluid and serum albumin. If Alb (serum) – Alb (PF) > 1.2 g/dL a transudative process is more likely. If you have a clinical situation where transudate seems more plausible, compare pleural fluid and serum albumin. If Alb (serum) – Alb (PF) > 1.2 g/dL a transudative process is more likely. An albumin difference of ≤ 1.2g/dL will incorrectly identify an effusion as exudative in 8% of cases. An albumin difference of ≤ 1.2g/dL will incorrectly identify an effusion as exudative in 8% of cases.

Algorithm for Evaluation of Pleural Effusions

Cell Count and Differential Neutrophilic: Neutrophilic: Seen when acute process is involving pleura Seen when acute process is involving pleura Parapneumonic, PE, Pancreatitis Parapneumonic, PE, Pancreatitis Lymphocytic Lymphocytic Malignancy or Tuberculosis Malignancy or Tuberculosis

Glucose Low glucose (<60mg/dL) in pleural fluid is an indication of: Low glucose (<60mg/dL) in pleural fluid is an indication of: Parapneumonic or Malignant Effusion Parapneumonic or Malignant Effusion Less commonly hemothorax, Tuberculosis, rheumatoid pleuritis Less commonly hemothorax, Tuberculosis, rheumatoid pleuritis

LDH Correlates to degree of pleural inflammation. Correlates to degree of pleural inflammation. An increasing LDH level on subsequent thoracenteses is suggestive of worsening inflammation. An increasing LDH level on subsequent thoracenteses is suggestive of worsening inflammation.

Cytology and Malignant Effusions 75% of malignant effusions are associated with lung carcinoma, breast carcinoma or lymphoma. 75% of malignant effusions are associated with lung carcinoma, breast carcinoma or lymphoma. Reported sensitivity of cytology for diagnosing the following: Reported sensitivity of cytology for diagnosing the following: Lymphoma (25-50%) Lymphoma (25-50%) Sarcoma Involving Pleura (25%) Sarcoma Involving Pleura (25%) Squamous Cell Carcinoma (20%) Squamous Cell Carcinoma (20%) Mesothelioma (10%) Mesothelioma (10%) Light, RW. Pleural Effusion. NEJM. 2002; 246:

Parapneumonic Features of pleural effusion that is suggestive of needing more invasive procedure than thoracentesis: Features of pleural effusion that is suggestive of needing more invasive procedure than thoracentesis: Loculated Pleural Fluid Loculated Pleural Fluid Pleural Fluid pH < 7.2 Pleural Fluid pH < 7.2 Pleural Fluid Glucose < 60mg/dL Pleural Fluid Glucose < 60mg/dL Positive Gram Stain or Culture Positive Gram Stain or Culture Gross pus in Pleural Space Gross pus in Pleural Space

Tuberculous Pleuritis Suspected based on History and a lymphocytic predominance on cell differentiation. Suspected based on History and a lymphocytic predominance on cell differentiation. Less than 40% of tuberculous effusions will have positive pleural-fluid culture. Less than 40% of tuberculous effusions will have positive pleural-fluid culture. Adenosine Deaminase is sensitive (99.6%) and specific (97.1%) when a cut-off of 40U/L is used. Adenosine Deaminase is sensitive (99.6%) and specific (97.1%) when a cut-off of 40U/L is used. Lee YCG, Rogers JT, Rodriguez RM, Miller KD and Light RW. Adenosine Deaminase Levels in Nontuberculous Lymphocytic Pleural Effusions. Chest 2001; 120:

Miscellaneous Pearls Elevated Amylase: suggestive of esophageal rupture or pancreatic disease Elevated Amylase: suggestive of esophageal rupture or pancreatic disease Eosinophilia: associated with Drug- Induced Effusions Eosinophilia: associated with Drug- Induced Effusions Fever, PMN predominance, no lung parenchymal lesion – intraabdominal abscess Fever, PMN predominance, no lung parenchymal lesion – intraabdominal abscess

References Aleman C, Alegre J, Armadans L. The Value of the Chest Roentgenography in the Diagnosis of Pneumothorax After Thoracentesis. American Journal of Medicine. 1999; 107: Kasper DL, Braunwald E, Fauci AS, Hauser SL, Longo DL, Jameson LJ eds. Harrison’s Principles of Internal Medicine. 16 th ed. New York: McGraw- Hill, Lee YCG, Rogers JT, Rodriguez RM, Miller KD and Light RW. Adenosine Deaminase Levels in Nontuberculous Lymphocytic Pleural Effusions. Chest 2001; 120: Light, RW. Pleural Effusion. NEJM. 2002; 246: Shinto RA and Light RW. Effects of Diuresis on the Characteristics of Pleural Fluid in Patients with Congestive Heart Failure. American Journal of Medicine. 1990; 88: