Useful for USMLE, Detailed, Anatomy, Physiology, PLAB

1. PLEURAL EFFUSION
By GBONEME S.E
Final year Medical Student, CMUL

2. Outline
• Introduction
• Epidemiology
• Anatomy of the pleural space
• Pathophysiology of PE
• Classification of pleural effusions
• Clinical presentation
• Management

3. Introduction
• Pleural effusion (PE) is abnormal accumulation
of fluid in the pleural space either due to excess
production or reduced absorption.
• Referred to as ‘water on the lungs’

4. Epidemiology
• Incidence of PE is 1.5 million per year
• All age groups can be affected
• Can be benign or malignant
• Right side is more commonly affected
• 2/3rds of malignant PE is seen in females

5. Anatomy of the pleural space
• Pleura is a serous membrane that lines the lungs
and inner aspect of the chest wall
• Its divided into 2: visceral and parietal
• Pleural space is the potential space between the
two layers
• Net fluid production is by the parietal layer and
net absorption is also via the parietal layer.
• The space normally contains a thin fluid (0.1-
0.2mls/kg)

6. Pathophysiology of PE
• Fluid movement across the capillary is guided by
starlings forces. These are Hydrostatic pressure
(HP), Oncotic pressure (OP), and capillary
permeability, as well as negative pressure in the
lymphatics and increased negative intrathoracic
pressure

7. Pathophysiology 2
• Increased HP, decreased OP, increased capillary
permeability and lymphatic obstruction or lung
collapse can lead to fluid accumulation in the
pleural space.

8. Pathophysiology 3
• Increased HP- congestive cardiac failure, renal
failure
• Decreased OP- liver cirrhosis, nephrotic
syndrome, other causes of hypoalbuminaemia
• Increased capillary permeability- metastasis,
infection, inflammation ( CT disease, irradiation,
cytotoxic drugs)
• Lymphatic obstruction- tumor, fibrosis induced
by irradiation and chemotherapy

9. Classification of PE
• Based on:
 appearance (Chylothorax, Hemothorax,
Bilothorax, pylothorax).
 Fluid chemistry (transudate and exudate)
 Location (Subpulmonic and lamellar)
 Presence of malignant cells (Malignant and
Benign)
 Compartmentalization (Simple or Loculated)

10. Fluid type/ Appearance
• Hydrothorax- serous fluid
• Haemothorax- blood
• Empyema/pyothorax- pus
• Chylothorax- chyle
• Urinothorax- urine
• Biliothorax- bile

11. Fluid chemistry
• Transudate- low protein content: Congestive
cardiac failure (CCF), liver cirrhosis, nephrotic
syndrome, peritoneal dialysis,urinothorax
• Exudate- high protein content: malignant,
infectious, haemothorax, CT disease,
chylothorax, uraemia, Meigs’ syndrome, drug
induced ( amiodarone, nitrofurantoin, ergot)

12. Association with malignancy
• Benign PE- not caused by malignant disease
• Malignant PE- caused by malignant disease

13. Benign PE
• Infective- TB, Pneumonia, Viral, Parasitic,
Fungal
pneumonia commonest in children
TB in adults
• Traumatic- blunt and penetrating
• Autoimmune DX: SLE, rheumatoid pleuritis,
• CCF, Liver cirrhosis, nephrotic syndrome
• Therapy-induced: irradiation, chemotherapy,
other drugs

14. Malignant PE
• These result from tumor invasion of the pleura
• Diagnosed by finding malignant cells in the fluid
or pleural tissue
• If caused by malignancy but no malignant cells
in fluid or pleural tissue it is called Para
malignant effusion.
• If caused by malignancy but no cytology:
malignancy associated pleural effusion.
• Result from lung, breast , GI, urogenital etc
mesothelioma, lymphoma,

15. Clinical presentation
• Dyspnoea (due to inability of Lung to expand)
• Cough (non productive as fluid is on the lungs)
• Pleuritic chest pain (during inspiration)
• Features of underlying disease (If CCF, RF,
nephrotic syndrome etc)

16. On Examination
• Asymmetric Chest
• Tracheal deviation to contralateral side
• Reduced Tactile fremitus on affected side
• Reduced percussion note on affected side
• Reduced breathe sounds on affected side

17. Investigations
• Haematology : FBC (features of elevated WBC if
pylothorax)
• Chemistry: Helps to differentiate between
transudate and exudate
• Microbiology: M/C/S
• Cytology: Rule out malignant cells
• Pleural biopsy
• Imaging
- CXR
- CT scan
- ultrasound scan

18. Imaging
• Chest X-ray: (PA view/ Lateral view)
1. Homogenous Opacification
2. Obliteration of Cardiophrenic angle
(accumulation of about 300mls of fluid)
3. Obliteration of Costophrenic angle
4. Meniscus sign
• USS: can pick as little as 50mls of fluid

19. Fluid Chemistry
• Light criteria (1972)
• Helps to differentiate between Exudate and
Transudate
• TS; Total Serum
Exudate Transudate
Pleural:TS protein
ratio
> 0.5 <0.5
Pleural: TS LDH
ratio
>0.6 <0.6
Pleural LDH Greater than
2/3rds of the
upper limit
Less than 2/3rds
of the upper limit

20. Fluid Chemistry 2
Modified Light Criteria
• HP/OP (Hydrostatic and Oncotic Pressure)
• SG – Specific Gravity
CRITERI
A
CAUSES APPERA
NCE
SG PROTEIN
not
ALBUMI
N
PLEURA
L
:SERUM
PROTEIN
CHOLES
TEROL
Pleural
LDH and
Upper
limit
SERUM
ALBUMI
N:PLEUR
AL
ALBUMI
N
EXUDAT
E
INFLAMM
ATION
CLOUDY >1.020 >2.9G/DL >0.5 >45mg/dl >2/3 <1.2G/DL
TRANSU
DATE
HP,OP CLEAR <1.012 <2.5G/DL <0.5 <45mg/dl <2/3 >1.2G/DL

21. Chest radiograph
• Homogenous
Opacification.

22. Chest radiograph 2
• Obliteration of the
Angles.

23. CT scan 1

24. Ultrasonography

25. Treatment
• Transudate, no symptoms, observe, treat underlying
cause .
• Exudates and symptomatic transudates:
• Needle aspiration
• Catheter drainage
• Tube thoracotomy: Closed Tube thoracotomy
drainage
• Fibrinolytics and Decortication - for stage 3
empyema
• Eloessar Window , empyectomy - Empyema

26. Treatment 2
• If malignant pleural effusion or recurrent benign
effusion:
- pleurodesis: Chemical (tetracycline, talc, silver
nitrate) Mechanical (surgically done),
Immunologic ( Use of staph super antigen)
- pleurectomy: Parietal pleura is stripped off. No
more pleural space
-shunts: Pleuroperitoneal shunts