Pleural Disease Flashcards
(45 cards)
Anatomy of the Pleural Space?
- Pleural space is 10 – 20 mm in width between the parietal and visceral pleura
- Pleural fluid is the interstitial liquid of the parietal pleura
- Both liquid and protein exit by parietal pleural stoma
- The volume of pleural fluid is 0.1 – 0.2 mL/kg of body weight
- Normal pleural fluid is clear and colorless with a protein concentration of < 1.5 g/dl and monocytes and mononuclear cells predominate
Hydrostatic and oncotic presures in the pleura?
Estimated hydrostatic and oncotic pressures in the parietal pleura and visceral pleura of the human lung that influence movement of liquid in and out of the pleural space. Note that the net pressure across both membranes favors movement into the pleural space.
Six mechanisms to increase the pleural fluid?
–increase in hydrostatic pressure in the microvascular circulation
–decrease in oncotic pressure in the microvascular circulation
–decrease in pressure in the pleural space (increase negative pleural pressure)
–increased permeability of the microvascular circulation
– Impaired lymphatic drainage from the pleural space
– Movement of fluid from the peritoneal space
Pleural effusion instances in the US?
basic steps of diagnosing a pleural effusion?
• History • Physical exam • Chest x-ray • Ultrasound • Thoracentesis
Pleural effusion history? Symptoms?
- Who has the effusion? • Does the patient have: –Heart failure –Known or suspected cancer –Cardiac arrhythmia –Connective tissue disorder –Viral pleurisy
- Symptoms to a large extent are dictated by the underlying process causing the effusion – Asymptomatic – Symptomatic – Dyspnea – Chest pain • Pleuritic • Dull – Cough – usually nonproductive – Fever
Pleural effusion on physical exam?
- Look for absent fremitus on affected side
- Listen for dullness to percussion and diminished breath sounds at the base
- Listen for rales immediately superior to area of dullness
- Try to elicit egophony
- Look for tracheal deviation
Radiographic studies for Pleural effusion?
–Standard chest x-ray PA and lateral
–Bilateral decubitus CXR
–Computed tomography (CT)
–Empyema vs. peripheral lung abscess
–Evaluation of lung parenchyma in undiagnosed exudative effusions
–Ultrasound
–Perfusion lung scan (rarely used) • Undiagnosed exudative effusion R/O PE
Explain lateral versus PA view for differing fluid levels?
What are the indications for thoracentesis?
- Relief of dyspnea –Large effusion –Small effusion with significant underlying lung dx
- Collection of fluid for diagnostic study
Analysis of pleural fluid what do we want to see?
• Color of the fluid • Odor of the fluid • Character of the fluid • Cell count with differential • Protein • LDH • Stains: Wright, gram, and acid-fast bacilli • Cultures: aerobic, anaerobic, mycobacterial and fungal • Glucose • pH • Cytology • Amylas
two types of pleural effusion?
- Transudate
- Exudate
Seperating transudates from exudates?
- PF/S protein ratio > 0.5
- PF/S LDH ratio > 0.6
- PF LDH > 0.67 of upper limits normal of serum
Transudative pleural effusion?
• Congestive heart failure (> 90%) • Nephrotic syndrome • Pulmonary embolism • Peritoneal dialysis • Post partum pleural effusion • Cirrhosis • Myxedema • Pericardial disease • Meigs’ syndrome • Malignancy (< 10%)
When is a diagnositc thoracentesis indicated for pleural effusion?
• Fever • Pleuritic chest pain • Unilateral effusion • Left effusion > right effusion • Effusions of disparate size • PaO 2 inconsistent with clinical presentation
What patients typically present with a bilateral transudate effusion?
–CHF
–Nephrotic syndrome
–Hypoalbuminemia
–Peritoneal dialysis
–Constrictive pericarditis
Patients who typically present with exudative bilateral effusions?
–Malignancy –Lupus pleuritis –Yellow Nail Syndrome
What things lead to exudative pleural effusions?
- Neoplastic diseases
- Infectious diseases
- Pulmonary embolization
- Gastrointestinal disease
- Collagen vascular disease
- Drug-induced pleural disease
- Other
Differentiating exudative pleural effusions?
• Appearance of the pleural fluid • Pleural fluid glucose • Pleural fluid amylase • Pleural fluid white cell count and differential • Pleural fluid cytology • Culture and bacteriologic stains
What do the different colors of effusion mean?
- White milky color suggests chylothorax
- Reddish tinge indicates blood
- Brownish color suggests rupture of an amebic liver abscess into the pleural space
- Black discoloration suggests aspergillus infection
What is a Chylothorax?
- White, odorless, and milky pleural fluid
- Triglyceride levels > 110 mg/dl
- Caused by disruptions of the thoracic duct
- > 50% 2° to tumor invading the thoracic lymph duct (lymphoma responsible for 75%)
- Trauma is the 2nd leading cause (25% of cases)
- Rare cause – pulmonary lymphangiomyomatosis
Explain Pseudochylous & Chyliform Effusions?
- Chylomicrons & fat globules are absent
- Pseudochylous –Lipid mainly comprises cholesterol crystals
- Chyliform –Lipid may be lecithin-globulin complexes
- Both seen in chromic pleural effusions from many causes (TB, Ca, RA, etc.)
Which count do we want on the pleural fluid?
- The differential cell count on the pleural fluid is much more helpful than the white cell count
- Partition cells into following categories: –Polymorphonuclear leukocytes –Eosinophils –Small lymphocytes –Mesothelial cells –Other mononuclear cells
What to think of when pleural fluid is predominately lymphocytes (>80%)
• Tuberculous pleurisy • Chylothorax • Lymphoma • Yellow nail syndrome • Rheumatoid pleurisy • Sarcoidosis • Trapped lung • Acute lung rejection
