The pleura is a membrane that covers the lungs and lines the chest cavity. Pleural effusions occur when there is an imbalance between pleural fluid formation and absorption, causing excess fluid in the pleural space. Effusions can be transudative or exudative based on fluid characteristics. Common causes include heart failure, pneumonia, cancer, and cirrhosis. Symptoms range from none to chest pain and dyspnea. Diagnosis involves chest imaging, fluid analysis, and other tests. Treatment focuses on resolving the underlying cause and draining significant fluid accumulations.

1. PLEURAL DISEASES

2. ANATOMY
• The pleura is the serous membrane that covers the lung
parenchyma, the mediastinum, the diaphragm, and the
rib cage. Lined by mesothelial cells

5. • it contributes to the elastic recoil of the lung, which is
important in expelling air from the lung
• it restricts the volume to which the lung can be inflated,
thereby protecting it
• Thin layer of fluid around 8 – 10ml in each
• Normal pleural fluid - ~ 2000 wbc/mm3, 70%
macrophages, 25% lymphocytes 700rbc/mm3
• Protein - ~1g%, sugar ~ plasma glucose
• Parietal pleura is pain sensitive

6. • Normal pleural fluid has the following characteristics:
• Clear ultrafiltrate of plasma that originates from the
parietal pleura
• A pH of 7.60-7.64
• Protein content of less than 2% (1-2 g/dL)
• Fewer than 1000 white blood cells (WBCs) per cubic
millimeter
• Glucose content similar to that of plasma
• Lactate dehydrogenase (LDH) less than 50% of
plasma

7. • Origin of pleural fluid - pleural capillaries, the interstitial
spaces of the lung, the intrathoracic lymphatics, the
intrathoracic blood vessels, or the peritoneal cavity
• 15ml/day ( 0.01ml/kg/day)
• Clearance – lymphatics in parietal pleura(0.4ml/kg/hr)
capillaries, transcytosis

8. PLEURAL EFFUSION

9. Mechanism of pleural effusion
• Increased pleural fluid formation
• Increased interstitial fluid in the lung
• Left ventricular failure, pneumonia, and pulmonary
embolus
• Increased intravascular pressure in pleura
• Right or left ventricular failure, superior vena caval
syndrome
• Increased permeability of the capillaries in the pleura
• Pleural inflammation
• Increased levels of vascular endothelial growth
factor
• Increased pleural fluid protein level

10. • Decreased pleural pressure
• Lung atelectasis or increased elastic recoil of the
lung
• Increased fluid in peritoneal cavity
• Ascites or peritoneal dialysis
• Disruption of the thoracic duct
• Disruption of blood vessels in the thorax

11. • Decreased pleural fluid absorption
• Obstruction of the lymphatics draining the parietal
pleura
• Elevation of systemic vascular pressures
• Superior vena caval syndrome or right ventricular
failure
• ?Disruption of the aquaporin system in the pleura

12. Transudative effusion
• Congestive heart failure
• Cirrhosis
• Pulmonary embolism
• Nephrotic syndrome
• Peritoneal dialysis
• Superior vena cava obstruction
• Myxedema
• Urinothorax

13. Exudative
• Neoplastic diseases
Metastatic disease
Mesothelioma
• Infectious diseases
Bacterial infections
Tuberculosis
Fungal infections
Viral infections
Parasitic infections

14. Pulmonary embolization
Gastrointestinal disease
Esophageal perforation
Pancreatic disease
Intraabdominal abscesses
Diaphragmatic hernia
After abdominal surgery
Endoscopic variceal sclerotherapy
After liver transplant

15. • Collagen vascular disease
• Post-coronary artery bypass surgery
• Asbestos exposure
• Sarcoidosis
• Uremia
• Meigs' syndrome
• Yellow nail syndrome

16. • Trapped lung
• Radiation therapy
• Post-cardiac injury syndrome
• Hemothorax
• Iatrogenic injury
• Ovarian hyperstimulation syndrome
• Pericardial disease
• Chylothorax

17. Drug-induced pleural disease
Nitrofurantoin
Dantrolene
Methysergide
Bromocriptine
Procarbazine
Amiodarone

18. CLINICAL FEATURES
• Asymptomatic
• arise either from inflammation of the pleura, from
compromise of pulmonary mechanics, from interference
with gas exchange, or on rare occasions, from
decreased cardiac output
• Inflammation -
• chest pain – pleuritic
• Subside or become dull aching when effusion
develops
• dry, nonproductive cough.

19. • Dyspnea –
• Small-to-moderate-sized pleural effusions displace
rather than compress the lung and have little effect on
pulmonary function

20. History focusing on etiology
• Fever , pleuritic chest pain – inflammatory
• With cough and expectoration – synpneumonic
• Weight loss, loss of apetite – chronic infections –TB,
malignancy
• Occupation – asbetosis
• Chest pain , hemoptysis, dyspnea –
• Drug exposure
• Repeated vomiting followed by chest pain, dyspnea –

21. • Abdominal pain radiating to back, left pleural effusion –
• Joint pains, rash, alopecia, oral ulcers
• Orthopnea, PND, pedal edema
• Anasarca , froathy urine
• Jaundice, abdominal distension in an alcoholic
• Smoker , expectoration , hemoptysis, hoarseness,
weight loss

22. SIGNS
• Trachea shift
• Mediastinum / apex
• Symmetry of hemithorax , intercostal spaces
• Chest movement
• Tactile vocal fremitus
• Percussion
• Shifting dullness
• Auscultation
• Air entry
• Upper border of effusion
• Egophony , whispering pectoriloqy

23. WORK UP
• Chest X- ray:
• 75 mL-subpulmonic space without spillover, can
obliterate the posterior costophrenic sulcus,
• 175 mL is necessary to obscure the lateral
costophrenic sulcus on an upright chest radiograph
• 500 mL will obscure the diaphragmatic contour on an
upright chest radiograph;
• 1000 ml of effusion reaches the level of the fourth
anterior rib,
• On decubitus radiographs and CT scans, less than 10
mL, and possibly as little as 2 mL, can be identified

24. Based on the decubitus films
• small effusions are thinner than 1.5 cm, moderate
effusions are 1.5 to 4.5 cm thick, and large effusions
exceed 4.5 cm.
• Effusions thicker than one cm are usually large
enough for sampling by thoracentesis, since at least
200 mL of liquid are already present

27. PLEURAL FLUID ANALYSIS
• INDICATION
• A pleural fluid thickness >10mm in lateral decubitus
CXR
• Complications. pain, bleeding (hematoma, hemothorax,
or hemoperitoneum), pneumothorax, empyema, soft
tissue infection, spleen or liver puncture, vasovagal
events, seeding the needle tract with tumor, and adverse
reactions to lidocaine or topical antiseptic
solutions,retained intrapleural catheter fragments

28. • Bloody – Hematocrit compared to the blood
• <1% is nonsignificant
• 1-20% indicates either cancer, PE or trauma
• >50% indicates hemothorax.
• Cloudy or Turbid – Centrifugation
• Turbid supernatant indicates high lipid levels
• Check TG - >110mg/dl – chylothorax
• If TG>50mg/dl and cholesterol>250 -
pseudochylothorax

30. • pH < 7.2 :
• complicated parapneumonic effusion
• esophageal rupture
• rheumatoid pleuritis
• tuberculous pleuritis
• malignant pleural disease
• hemothorax
• systemic acidosis
• lupus pleuritis
• urinothorax

31. EXUDATE
• pleural fluid protein > 3.0
g/dL
• Pleural fluid protein > 0.5
serum protein
• Pleural fluid LDH >0.6
serum LDH
• Pleural fluid LDH greater
than two thirds of the
upper limit of normal
serum LDH
TRANSUDATE
• Protein <3g/dl
• <0.5
• <0.6
• less

32. EXUDATE
• pleural fluid cholesterol
>60mg/dl
• SPAG <1.2g
• pleural fluid-to-serum
bilirubin ratio above 0.6
• Wbc > 1000
• Glucose < serum
TRANSUDATE
• Clear
• Straw colored
• Nonviscid
• Odorless
• Wbc <1000
• Glucose = serum

33. • Microbiology :
• Gram stain
• AFB
• Culture
• ADA - >43 – may suggest TB
• Cytology

34. • USG
• CT scan
• Bronchoscopy
• Pleural biopsy

35. PARAPNEUMONIC EFFUSION
• Any pleural effusion associated with bacterial
pneumonia, lung abscess, or bronchiectasis is a
parapneumonic effusion

36. 1. Nonsignificant - Small <10 mm thick on decubitus x-
ray study - Rx – antibiotics
2. Typical parapneumonic - >10 mm thick
Glucose >40 mg/dL, pH >7.2
Gram's stain and culture negative
Rx – antibiotics
3. Borderline complicated - 7.0 <pH <7.20 and/or
LDH >3 × upper limit normal and glucose >40 mg/dL
Gram's stain and culture negative
Antibiotics plus serial thoracentesis

37. 4. Simple complicated : pH <7.0 or glucose <40 mg/dL
Gram's stain or culture positive
Not loculated not frank pus
Tube thoracostomy plus antibiotics
5. Complex complicated :
pH <7.0 and/or glucose <40 mg/dL or
Gram's stain or culture positive, Multiloculated
Tube thoracostomy plus fibrinolytics (rarely require
thoracoscopy or decortication)
6. Simple empyema:
Frank pus present, Single locule or free flowing
Tube thoracostomy ± decortication

38. • 7. Complex empyema:
Frank pus present, Multiple locules
Tube thoracostomy ± fibrinolytics
Often require thoracoscopy or decortication

39. TREATMENT
• TREAT THE CAUSE
• Thoracocentesis :
• Loculated pleural fluid
• Pleural fluid pH <7.20
• Pleural fluid glucose <40mg/dl
• Positive Gram stain or culture of the pleural fluid
• Presence of gross pus in the pleural space