Pleural fluid examination

1. Pleural Fluid Pleural Fluid
ExaminationExamination
Presented By:Presented By:
Nasir NazeerNasir Nazeer

2. Pleural FluidPleural Fluid
Pleural fluid is the fluid that is found between the layers of Pleural fluid is the fluid that is found between the layers of
the pleura, the membranes that line the thoracic cavity the pleura, the membranes that line the thoracic cavity
and surround the lungs. and surround the lungs.
The space containing the fluid is referred as the pleural The space containing the fluid is referred as the pleural
cavity. cavity.
Normal pleural fluid consists of a small amount of a thin Normal pleural fluid consists of a small amount of a thin
(serous) fluid that functions as a lubricant during (serous) fluid that functions as a lubricant during
breathing.breathing.
An excess amount of pleural fluid can be caused by many An excess amount of pleural fluid can be caused by many
conditions and is known as a pleural effusion.conditions and is known as a pleural effusion.
Some common causes of pleural effusions include heart Some common causes of pleural effusions include heart
failure, pneumonia, and autoimmune diseases such failure, pneumonia, and autoimmune diseases such
as rheumatoid arthritis.as rheumatoid arthritis.

3. Pleural FluidPleural Fluid
If doctor finds that patient have too much pleural fluid, he may If doctor finds that patient have too much pleural fluid, he may
recommend that a sample of the fluid be removed by a procedure recommend that a sample of the fluid be removed by a procedure
called thoracentesis and sent for analysis to help determine the called thoracentesis and sent for analysis to help determine the
cause (pleural fluid cytology).cause (pleural fluid cytology).
With lung cancer, an excess amount of pleural fluid (pleural With lung cancer, an excess amount of pleural fluid (pleural
effusion) is quite common, and can be either benign (non-effusion) is quite common, and can be either benign (non-
cancerous) or due to the spread of lung cancer cells into the pleural cancerous) or due to the spread of lung cancer cells into the pleural
cavity (malignant pleural effusion).cavity (malignant pleural effusion).
Pleural fluid analysis is used to help diagnose the cause of Pleural fluid analysis is used to help diagnose the cause of
inflammation of the pleura (pleuritis) and/or accumulation of fluid in inflammation of the pleura (pleuritis) and/or accumulation of fluid in
the pleural space (pleural effusion). There are two main reasons for the pleural space (pleural effusion). There are two main reasons for
fluid accumulation, and an initial set of tests (fluid protein, albumin, fluid accumulation, and an initial set of tests (fluid protein, albumin,
or LDH level, cell count, and appearance) is used to differentiate or LDH level, cell count, and appearance) is used to differentiate
between the two types of fluid that may be produced.between the two types of fluid that may be produced.

4. Pleural Fluid (Transudate)Pleural Fluid (Transudate)
An imbalance between the pressure within blood An imbalance between the pressure within blood
vessels (which drives fluid out of the blood vessels (which drives fluid out of the blood
vessel) and the amount of protein in blood vessel) and the amount of protein in blood
(which keeps fluid in the blood vessel) can result (which keeps fluid in the blood vessel) can result
in accumulation of fluid (called a transudate). in accumulation of fluid (called a transudate).
Transudates are most frequently caused Transudates are most frequently caused
by congestive heart failure or cirrhosis. If the by congestive heart failure or cirrhosis. If the
fluid is determined to be a transudate, then fluid is determined to be a transudate, then
usually no more tests on the fluid are necessary.usually no more tests on the fluid are necessary.

5. Pleural Fluid (Exudate)Pleural Fluid (Exudate)
Injury or inflammation of the pleurae may cause abnormal collection of Injury or inflammation of the pleurae may cause abnormal collection of
fluid (called an exudate). If the fluid is an exudate, then additional fluid (called an exudate). If the fluid is an exudate, then additional
testing is often ordered. Exudates are associated with a variety of testing is often ordered. Exudates are associated with a variety of
conditions and diseases, including:conditions and diseases, including:

Infectious diseases – caused by viruses, bacteria, or fungi. Infections may Infectious diseases – caused by viruses, bacteria, or fungi. Infections may
originate in the pleurae or spread there from other places in the body. For originate in the pleurae or spread there from other places in the body. For
example, pleuritis and pleural effusion may occur along with or following example, pleuritis and pleural effusion may occur along with or following
pneumonia.pneumonia.

Bleeding – bleeding disorders, pulmonary embolism, or trauma can lead to Bleeding – bleeding disorders, pulmonary embolism, or trauma can lead to
blood in the pleural fluid.blood in the pleural fluid.

Inflammatory conditions – such as lung diseases, chronic lung Inflammatory conditions – such as lung diseases, chronic lung
inflammation for example due to prolonged exposure to large amounts of inflammation for example due to prolonged exposure to large amounts of
asbestos (asbestosis), sarcoidosis, or auto-immune disorders such asbestos (asbestosis), sarcoidosis, or auto-immune disorders such
as rheumatoid arthritis and systemic lupus erythematosusas rheumatoid arthritis and systemic lupus erythematosus

Malignancies – such as lymphoma, leukemias, lung Malignancies – such as lymphoma, leukemias, lung
cancer, metastatic cancerscancer, metastatic cancers

Other conditions – idiopathic, cardiac bypass surgery, heart or lung Other conditions – idiopathic, cardiac bypass surgery, heart or lung
transplantation, pancreatitis, or intra-abdominal abscessestransplantation, pancreatitis, or intra-abdominal abscesses

6. Additional testing on exudate fluid Additional testing on exudate fluid
Pleural fluid glucose, lactate, amylase, triglyceride, and/or tumor Pleural fluid glucose, lactate, amylase, triglyceride, and/or tumor
markersmarkers
Microscopic examination – Normal pleural fluid has small numbers of Microscopic examination – Normal pleural fluid has small numbers of
white blood cells (WBCs) but no red blood cells (RBCs) white blood cells (WBCs) but no red blood cells (RBCs)
or microorganisms. Laboratories may examine the pleural fluid and/or or microorganisms. Laboratories may examine the pleural fluid and/or
use a special centrifuge (cytocentrifuge) to concentrate the fluid's cells use a special centrifuge (cytocentrifuge) to concentrate the fluid's cells
on a slide. The slide is treated with a special stain and evaluated for on a slide. The slide is treated with a special stain and evaluated for
the different kinds of cells that may be present.the different kinds of cells that may be present.
Gram stain – for direct observation of bacteria or fungi under a Gram stain – for direct observation of bacteria or fungi under a
microscope. There should be no organisms present in pleural fluid.microscope. There should be no organisms present in pleural fluid.
Bacterial culture and susceptibility testing – ordered to detect any Bacterial culture and susceptibility testing – ordered to detect any
microorganisms that may be present in the pleural fluid and to guide microorganisms that may be present in the pleural fluid and to guide
antimicrobial therapy.antimicrobial therapy.
Less commonly ordered tests for infectious diseases, such as tests Less commonly ordered tests for infectious diseases, such as tests
for viruses, mycobacteria (AFB smear and culture), and parasites. for viruses, mycobacteria (AFB smear and culture), and parasites.

7. How to prepare patient for the How to prepare patient for the
Test?Test?
The test is no more invasive than having The test is no more invasive than having
blood drawn. There is no special blood drawn. There is no special
preparation. preparation.
Patient should not cough, breathe deeply, Patient should not cough, breathe deeply,
or move during the test to avoid injury to or move during the test to avoid injury to
the lung.the lung.
Patient may have a chest x-ray before or Patient may have a chest x-ray before or
after the test. after the test.

8. How to prepare patient for the How to prepare patient for the
Test?Test?
(Contd…)(Contd…)
Patient should be directed to sit on the edge of a chair or Patient should be directed to sit on the edge of a chair or
on bed with his head and arms resting on a table. on bed with his head and arms resting on a table.
Clean the skin around the insertion site and drape the Clean the skin around the insertion site and drape the
area. A local pain-killing medicine (anesthetic) is injected area. A local pain-killing medicine (anesthetic) is injected
into the skin, which stings a bit, but only for a few into the skin, which stings a bit, but only for a few
seconds.seconds.
The thoracentesis needle is inserted above the rib into the The thoracentesis needle is inserted above the rib into the
pocket of fluid. pocket of fluid.
As fluid drains into a collection bottle, many people cough As fluid drains into a collection bottle, many people cough
a bit as the lung re-expands to fill the space where fluid a bit as the lung re-expands to fill the space where fluid
had been. This sensation normally lasts for a few hours had been. This sensation normally lasts for a few hours
after the test is completed.after the test is completed.
Patient should tell to health care provider if he has sharp Patient should tell to health care provider if he has sharp
chest pain or shortness of breath chest pain or shortness of breath

10. Risks involved in ThoracentesisRisks involved in Thoracentesis
Collapse of the lung (pneumothorax)Collapse of the lung (pneumothorax)
Excessive loss of bloodExcessive loss of blood
Fluid re-accumulationFluid re-accumulation
InfectionInfection
Pulmonary edemaPulmonary edema
Respiratory distressRespiratory distress
FaintingFainting

11. Test results interpretationTest results interpretation
Test results can help to distinguish Test results can help to distinguish
between types of pleural fluid and help to between types of pleural fluid and help to
diagnose the cause of fluid accumulation. diagnose the cause of fluid accumulation.
The initial set of tests performed on a The initial set of tests performed on a
sample of pleural fluid helps determine sample of pleural fluid helps determine
whether the fluid is whether the fluid is
a transudate or exudate.a transudate or exudate.

12. Transudate Fluid and test resultsTransudate Fluid and test results
Transudates are most often caused by Transudates are most often caused by
either congestive heart failure or cirrhosis. either congestive heart failure or cirrhosis.
Typical fluid analysis results include:Typical fluid analysis results include:
Physical characteristics—fluid appears Physical characteristics—fluid appears
clearclear
Protein, albumin, or LDH level—lowProtein, albumin, or LDH level—low
Cell count—few cells are presentCell count—few cells are present

13. Exudate Fluid and test resultsExudate Fluid and test results
Exudates can be caused by a variety of conditions and Exudates can be caused by a variety of conditions and
diseases. Initial test results may include:diseases. Initial test results may include:

Physical characteristics—fluid may appear cloudyPhysical characteristics—fluid may appear cloudy

Protein, albumin, or LDH level—highProtein, albumin, or LDH level—high

Cell count—increasedCell count—increased

Additional test results and their associated causes may include:Additional test results and their associated causes may include:
Physical characteristicsPhysical characteristics

The normal appearance of a sample of pleural fluid is usually light The normal appearance of a sample of pleural fluid is usually light
yellow and clear. Abnormal results may give clues to the yellow and clear. Abnormal results may give clues to the
conditions or diseases present and may include:conditions or diseases present and may include:

Milky appearance may point to lymphatic system involvement.Milky appearance may point to lymphatic system involvement.

Reddish pleural fluid may indicate the presence of blood.Reddish pleural fluid may indicate the presence of blood.

Cloudy, thick pleural fluid may indicate the presence Cloudy, thick pleural fluid may indicate the presence
of microorganisms and/or white blood cells.of microorganisms and/or white blood cells.

14. Exudate Fluid and test results Exudate Fluid and test results
(Contd…)(Contd…)
Chemical testsChemical tests – tests that may be performed in – tests that may be performed in
addition to protein or albumin may include:addition to protein or albumin may include:
Glucose—typically about the same as blood Glucose—typically about the same as blood
glucose levels. May be lower with infection glucose levels. May be lower with infection
and rheumatoid arthritis.and rheumatoid arthritis.
Lactate levels can increase with infectious pleuritis, Lactate levels can increase with infectious pleuritis,
either bacterial or tuberculosis.either bacterial or tuberculosis.
Amylase levels may increase with pancreatitis, Amylase levels may increase with pancreatitis,
esophageal rupture, or malignancy.esophageal rupture, or malignancy.
Triglyceride levels may be increased with lymphatic Triglyceride levels may be increased with lymphatic
system involvement.system involvement.
Tumor markers may be increased with some cancers.Tumor markers may be increased with some cancers.

15. Exudate Fluid and test results Exudate Fluid and test results
(Contd…)(Contd…)
Microscopic examinationMicroscopic examination  

Normal pleural fluid has small numbers of white blood cells (WBCs) but Normal pleural fluid has small numbers of white blood cells (WBCs) but
no red blood cells (RBCs) or microorganisms. Results of an evaluation no red blood cells (RBCs) or microorganisms. Results of an evaluation
of the different kinds of cells present may include:of the different kinds of cells present may include:

Total cell counts—the WBCs and RBCs in the sample are counted. Total cell counts—the WBCs and RBCs in the sample are counted.
Increased WBCs may be seen with infections and other causes of Increased WBCs may be seen with infections and other causes of
pleuritis. Increased RBCs may suggest trauma, malignancy, or pleuritis. Increased RBCs may suggest trauma, malignancy, or
pulmonary infarction.pulmonary infarction.

WBC differential—determination of percentages of different types of WBC differential—determination of percentages of different types of
WBCs. An increased number of neutrophils may be seen with bacterial WBCs. An increased number of neutrophils may be seen with bacterial
infections. An increased number of lymphocytes may be seen with infections. An increased number of lymphocytes may be seen with
cancers and tuberculosis.cancers and tuberculosis.
Cytology – a cyto-centrifuged sample is treated with a special stain Cytology – a cyto-centrifuged sample is treated with a special stain
and examined under a microscope for abnormal cells. This is often and examined under a microscope for abnormal cells. This is often
done when a mesothelioma or metastatic cancer is suspected. The done when a mesothelioma or metastatic cancer is suspected. The
presence of certain abnormal cells, such as tumor cells or immature presence of certain abnormal cells, such as tumor cells or immature
blood cells, can indicate what type of cancer is involved.blood cells, can indicate what type of cancer is involved.

16. Exudate Fluid and test results Exudate Fluid and test results
(Contd…)(Contd…)
Infectious disease testsInfectious disease tests  
Following tests may be performed to look for microorganisms if Following tests may be performed to look for microorganisms if
infection is suspected:infection is suspected:
Gram stainGram stain – for direct observation of bacteria or fungi under a – for direct observation of bacteria or fungi under a
microscope. There should be no organisms present in pleural fluid.microscope. There should be no organisms present in pleural fluid.
Bacterial culture and susceptibility testing – If bacteria are present, Bacterial culture and susceptibility testing – If bacteria are present,
susceptibility testing can be performed to guide antimicrobial therapy. susceptibility testing can be performed to guide antimicrobial therapy.
If there are no microorganisms present, it does not rule out an If there are no microorganisms present, it does not rule out an
infection; they may be present in small numbers or their growth may infection; they may be present in small numbers or their growth may
be inhibited because of prior antibiotic therapy.be inhibited because of prior antibiotic therapy.
Less commonly, if testing for other infectious diseases is performed Less commonly, if testing for other infectious diseases is performed
and is positive, then the cause of the pericardial fluid accumulation and is positive, then the cause of the pericardial fluid accumulation
may be due to a viral infection, mycobacteria (such as the may be due to a viral infection, mycobacteria (such as the
mycobacterium that causes tuberculosis), or aparasite.mycobacterium that causes tuberculosis), or aparasite.