Approach to Pleural Effusion
 Dr Abdalla Elfateh Ibrahim
 Consultant & Assisstant Professor
of Pulmonary Medicine
 King Saud University
Pleural Effusion
 Pleural effusions are a common medical problem
 with more than 50 recognized causes including
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Local pleura disease
Underlying lung
Systemic conditions
Organ dysfunction
Drugs
It occur as a result of increased fluid formation and/or
reduced fluid resorption.
Mechanism
 The pathophysiology of fluid accumulation
varies according to underlying aetiologies.
 Increase permeability
 Increase pulmonary capillary pressure
 Decrease negative pleural pressure
 Decrease oncotic pressure
 Obstructed lymphatics
Types of pleural effusions
 Transudates pleural fluid proteins < 30
OR
 Exudates
pleural fluid proteins >30
Causes of pleural effusion
Transudates
 Very Common causes
 Heart failure
 Liver cirrhosis
Transudates
 Less Common causes
 Hypoalbuminaemia
 Peritoneal dialysis
 Hypothyroidism
 Nephrotic syndrome
 Mitral Stenosis
Causes of pleural exudates
Common causes
 Malignancy
 Parapneumonic effusions
 Tuberculosis
Exudates
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Less Common causes
Pulmonary embolism
Rheumatoid arthritis and other autoimmune
pleuritis
Benign Asbestos effusion
Pancreatitis
Post-myocardial infarction
Post CABG
Exudates
 Rare causes
 Yellow nail syndrome (and other lymphatic
disorders )
 Drugs
 Fungal infections
Clinical assessment and history
 Thorough history
(Infection, malignancy , risk of PE , heart failure etc.)
 And physical examination.
History
 Drug history is important.
Uncommon cause of exudative effusion
(mesotruxate, Amiodarone Phenytoin, Nitrofurantoin and
Beta- blockers )
>100 cases reported globally
 An occupational history
 Asbestos exposure and potential secondary exposure via
parents or spouses should be documented.
Symptoms
 Asymptomatic
 Breathlessness
 Chest pain
 Cough
 Fever
 Approximately 75% of patients with pulmonary
embolism and pleural effusion have a history of
pleuritic pain.
 Dyspnoea is often out of proportion to the size
of the effusion
 Asymptomatic if it occupies less than a third of
the hemithorax
Signs
 Decrease expansion
 Dull percusion node
 Decrease vocal resonance
 Decrease air entry
 Signs of associated disease
(for example :chronic liver disease-CCFnephrotic syndrome -SLE-RA-Ca lung)
DIAGNOSIS
 CXR
 Pleural aspiration
 Pleural biopsy
 Medical thoracoscopy
 CT scan
 VAT
 Bronchoscopy
CXR
Diagnostic Imaging
Pleural aspiration
 The initial step in assessing a pleural effusion is
to ascertain whether the effusion is a
transudate or exudate
 Diagnostic tap
 Aspiration should not be performed for bilateral
effusions in a clinical setting strongly suggestive
of a transudate, unless there are atypical
features or they fail to respond to therapy
Pleural aspiration
 A diagnostic tap, with a fine bore (21G) needle
and a 50mL syringe
 Bedside ultrasound guidance is recommended
for all diagnostic aspirations
 Biochemistry : protein, LDH, PH, and glucose
 Microbiology: Gram stain, AFB and culture
 Pathology :cytology
Pleural aspiration
 Aspirated fluid should immediately be drawn
into a blood gas syringe for PH
 Biochemical (2-5 ml)
 Microbiology 5ml
 50ml for cytological examination
Pleural effusion
 Document in the patient file :
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Aseptic techique (under local Anathesia)
The amount of effusion aspirated
Appearance and odour should be noted.
(colour usually Straw colour (normal)
Smell , unpleasant aroma of anaerobic
infection may guide antibiotic
The appearance may be serous blood tinged
or frankly bloody
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Appearance
 Milky fluid
Empyaema
Chylothorax
PesudoChylothorax
 Centrifuging turbid or milky pleural fluid will
distinguish between empyema and lipid
effusions.
 If the supernatant is clear then the turbid
fluid was due to empyema
 If it is still turbid :
-Chylothorax
OR
- Pseudochylothorax
Appearance
 Grossly bloody pleural fluid is usually due to
 Malignancy
 Pulmonary embolus with infarction
 Trauma
 Benign asbestos pleural effusions
 Post-cardiac injury syndrome
How to differentiate between
haemothorax & hagic effusion
 Pleural fluid haematocrit is greater than
50% of the patient's peripheral blood
haematocrit is diagnostic of a haemothorax
Fluid Suspected disease
 Putrid odour Anaerobic empyema
 Food particles Oesophageal rupture
 Bile stained Cholothorax (biliary fistula)
 Milky Chylothorax/Pseudochylothorax
 ‘Anchovy sauce’ like fluid Ruptured amoebic
abscess
Differentiating between exudate
and transudate effusions
 Protein of > 30g/l an exudate
 Protein of <30 g/l a transudate.
 When
protein is close to 30g/l (25-30)
Light's criteria
 Exudates if one or more of the following:
 Pleural fluid protein divided by serum protein
is greater than 0.5
 Pleural fluid LDH divided by serum LDH is
greater than 0.6
 Pleural fluid LDH > 2/3 the upper limits of
laboratory normal value for serum LDH.
How accurate is Light’s criteria ?
 In CCF diuretic therapy increases the
concentration of protein, LDH and lipids in
pleural fluid
 In this context Light's criteria is recognized to
misclassify a significant proportion of effusions
as exudates .
 Clinical judgment should be used
 Measurement of NT-pro-BNP can be useful.
Other tests
 Glucose < 3.3 mmol/l ? Infection
 PH
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<7.2 empyaema
Amylase pancreatic ca ,rupture oesophagus
Rheumatoid factor RA
ANA for SLE
Complement level (reduced in SLE,RA,Ca)
Pleural fluid differential
cell counts
 Cell proportions are helpful in narrowing the differential
diagnosis but none are disease specific
 When any effusion becomes long standing it tends to be
populated by lymphocytes (and neutrophils fade away)
 Pleural malignancy, cardiac failure and tuberculosis are
common specific causes of a lymphocytic effusion
PH
 Pleural fluid pH should be measured in nonpurulent effusions providing that appropriate
collection technique can be observed and a blood
gas analyser is available.
 Inclusion of air or local anesthetic in samples may
significantly alter the pH results and should be
avoided.
 In a parapneumonic effusion, a pH <7.2 indicates
the need for tube drainage
PH
 In clinical practice, the most important use
for pleural fluid pH is aiding the decision to
treat pleural infection with tube drainage.
Pleural effusion cells (cont)
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Neutrophil (are associated with acute processes)
Parapneumonic effusions:
Pulmonary embolism
Acute TB
Benign asbestos related disease
Eosinophils
Pleural eosinophilia when eosinophyls are greater than
10% of cells ( eosinophilic effusion)
 The most common cause eosinophilia is air or blood in
the pleural space
 Is a fairly non-specific
Causes of lymphocytic p. effusions
 lymphocytes account for > 50% nucleated
cells)
 Malignancy (including metastatic
adenocarcinoma and mesothelioma)
 Lymphoma
 Tuberculosis
Causes of lymphocytic pleural
effusions
 Cardiac failure
 Post CABG
 Rheumatoid effusion
 Chylothorax
 Uraemic pleuritis
 Sarcoidosis
 Yellow Nail Syndrome
Glucose
 In the absence of pleural pathology, glucose diffuses
freely across the pleural membrane and pleural fluid
glucose concentration is equivalent to blood
 A low pleural fluid glucose level (< 3.4 mmol/l) may be
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found in
Complicated parapneumonic effusions
Empyema
Rheumatoid pleuritis
Tuberculosis
Malignancy
Oesophageal rupture .
Glucose
 The most common causes of a very low pleural fluid
glucose level (< 1.6 mmol/l) are
 Rheumatoid arthritis
 Empyema
 Although glucose is usually low in pleural infection and
correlates to pleural fluid pH values, it is a significantly
less accurate indicator for chest tube drainage when
compared to pH
Cytology
 The diagnostic yield for malignancy depends on
 The skill and interest of the cytologist
 Tumour type.
 The diagnostic rate is higher for adenocarcinoma
 Than for
 Mesothelioma,
 Squamous cell carcinoma
 lymphoma and sarcoma.
Tumour markers
 Pleural fluid and serum tumour markers
do not have a role in the investigation of
pleural effusions.
Management
 Treatment of the cause
 Drainage
(stop drain for 1-2 hours after 1st 1500 ml)
may presipitate pul oedema
 Pleurodesis with
- Talc
- Tetracycline
-Bleomycin
Surgery