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(Pleural Tap, Pleural Fluid Analysis)
Thoracentesis is a procedure in which a needle is inserted through the back of the chest wall into the pleural space (a space that exists between the two lungs and the interior chest wall) to remove fluid or air. Pleural fluid analysis is the microscopic and chemical lab analysis of the fluid obtained during thoracentesis.
The normal function of the lungs is to expand with each breath taken in (like a balloon), fitting closely to the rib cage. With each expansion of the lungs, there is a corresponding expansion of the chest. There is only a little space (the pleural space) between the lungs and the interior wall of the chest. The pleural space is lubricated by fluid that is secreted and reabsorbed at relatively constant rates by the pleura (tissue that encases the lungs). Because of the constant rate of secretion and reabsorption, there is generally only a small amount of fluid in the area at any time. The pleural fluid functions to prevent friction against the chest wall as the lungs inflate and deflate with breathing.
In a disease process, the pleural space may fill with fluid, such as blood, pus (from infection), serum, or lymph. Alternately, the pleural fluid may be prevented from being reabsorbed, causing an accumulation of fluid in the pleural space. When such an accumulation occurs, it becomes difficult for the lungs to fully inflate because of the fluid pressing on the lungs. Pleural fluid accumulation can cause shortness of breath, which may become more pronounced with increased activities. It may become necessary to perform a thoracentesis to remove the fluid.
The accumulation of fluid in the pleural space, referred to as a pleural effusion, indicates an abnormality. A thoracentesis may be performed to identify the reason (diagnostic) and/or to relieve the discomfort and symptoms (therapeutic) of excessive fluid in the pleural space.
A diagnostic thoracentesis involves the removal of fluid for analysis (pleural fluid analysis). In general, pleural fluid is classified as exudate (seen in inflammatory, cancerous, or infectious conditions) or transudate (fluid that has leaked from blood or lymph vessels for various reasons). Pleural fluid analysis may help to confirm or rule out infections or diseases such as cancer, congestive heart failure, liver failure, or pulmonary hypertension (high pressure in the lungs’ blood vessels). Therapeutic thoracentesis may help to relieve discomfort from shortness of breath due to the pressure caused by fluid accumulation.
Other related procedures that may be used to diagnose problems with the lungs and respiratory tract include bronchoscopy, computed tomography (CT scan) of the chest, chest fluoroscopy, chest x-ray, chest ultrasound, lung biopsy, lung scan, mediastinoscopy, oximetry, peak flow measurement, positron emission tomography (PET) scan, pleural biopsy, pulmonary angiography, and pulmonary function tests. Please see these procedures for additional information.
The respiratory system is made up of the organs involved in the interchanges of gases, and consists of the:
The upper respiratory tract includes the:
The lower respiratory tract includes the lungs, bronchi, and alveoli.
The lungs take in oxygen, which cells need to live and carry out their normal functions. The lungs also get rid of carbon dioxide, a waste product of the body's cells.
The lungs are a pair of cone-shaped organs made up of spongy, pinkish-gray tissue. They take up most of the space in the chest, or the thorax (the part of the body between the base of the neck and diaphragm).
The lungs are enveloped in a membrane called the pleura.
The lungs are separated from each other by the mediastinum, an area that contains the following:
The right lung has three sections, called lobes. The left lung has two lobes. When you breathe, the air enters the body through the nose or the mouth. It then travels down the throat through the larynx (voice box) and trachea (windpipe) and goes into the lungs through tubes called main-stem bronchi.
One main-stem bronchus leads to the right lung and one to the left lung. In the lungs, the main-stem bronchi divide into smaller bronchi and then into even smaller tubes called bronchioles. Bronchioles end in tiny air sacs called alveoli.
Thoracentesis may be performed for diagnostic and/or therapeutic reasons. The diagnostic use of a thoracentesis involves pleural fluid analysis to distinguish between exudate, which may result from inflammatory or malignant conditions, and transudate, which may result from failure of organ systems that affect fluid balance in the body. This analysis aids in determining the cause of the abnormality.
The diagnostic findings are classified into two categories, exudate and transudate, and include, but are not limited to, the following:
The therapeutic use of thoracentesis may be helpful in relieving symptoms such as shortness of breath and pain.
There may be other reasons for your physician to recommend a thoracentesis and a pleural fluid analysis.
As with any surgical procedure, complications can occur. Some possible complications may include, but are not limited to, the following:
Thoracentesis is contraindicated in certain bleeding conditions.
Patients who are allergic to or sensitive to medications, contrast dyes, iodine, or latex should notify their physician.
If you are pregnant or suspect that you may be pregnant, you should notify your physician.
There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.
A thoracentesis may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your physician’s practices.
Generally, a thoracentesis follows this process:
After the procedure, you will be monitored until your blood pressure, pulse, and breathing are stable. If the procedure was done at the bedside, you will remain in your hospital room. If the procedure was performed on an outpatient basis, you will be discharged to your home, unless your physician decides otherwise. If the procedure was performed on an outpatient basis, you should plan to have another person drive you home.
The dressing over the puncture site will be monitored for bleeding or other drainage.
You will be positioned in a side-lying position with the unaffected side down for an hour or longer.
You may have a chest x-ray performed after the procedure.
When the recovery period is over, you may resume your usual diet and activities unless your physician advises you differently.
Notify your physician to report any of the following:
Your physician may give you additional or alternate instructions after the procedure, depending on your particular situation.
The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease, or replace the professional medical advice you receive from your physician. Please consult your physician with any questions or concerns you may have regarding your condition.
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