Pleural fluid analysis

定义

Pleural fluid analysis is a test that examines a sample of fluid that has collected in the pleural space. This is the space between the lining of the outside of the lungs (pleura) and the wall of the chest. When fluid collects in the pleural space, the condition is called 胸腔积液.

How the Test is Performed

这个过程叫做 胸腔穿刺术 is used to get a sample of pleural fluid. The health care provider examines the sample to look for:

• 癌症ous (malignant) cells
• Other types of cells (for example blood cells)
• Levels of glucose, protein and other chemicals
• Bacteria, fungi, mycobacteria, viruses, and other germs that can cause infections
• 炎症

How to Prepare for the Test

No special preparation is needed before the test. An ultrasound, CT scan, or 胸部x光片 will be performed before and after the test.

DO NOT cough, breathe deeply, or move during the test to avoid injury to the lung.

Tell your provider if you take medicines to thin the blood.

How the Test will Feel

For 胸腔穿刺术, you sit on the edge of a chair or bed with your head and arms resting on a table. The provider cleans the skin around the insertion site. Numbing medicine (anesthetic) is injected into the skin.

A needle is placed through the skin and muscles of the chest wall into the pleural space. As fluid drains into a collection bottle, you may cough a bit. This is because your lung re-expands to fill the space where fluid had been. This sensation lasts for a few hours after the test.

During the test, tell your provider if you have sharp chest pain or shortness of breath.

Ultrasound is often used to decide where the needle is inserted and to get a better view of the fluid in your chest.

Why the Test is Performed

The test is performed to determine the cause of a 胸腔积液. It is also done to relieve the shortness of breath that a large 胸腔积液 can cause.

正常的结果

Normally the pleural cavity contains less than 20 milliliters (4 teaspoons) of clear, yellowish (serous) fluid.

What Abnormal Results Mean

Abnormal results may indicate possible causes of 胸腔积液, such as:

• 癌症
• 肝硬化
• 心脏衰竭
• 感染
• 严重的 营养不良
• 创伤
• Abnormal connections between the pleural space and other organs (for example, the esophagus)

If the provider suspects an infection, a culture of the fluid is done to check for bacteria and other microbes.

The test may also be performed for 血胸. This is a collection of blood in the pleura.

风险

风险 of 胸腔穿刺术 are:

• 肺萎陷(气胸)
• Excessive loss of blood
• Fluid re-accumulation
• 感染
• 肺水肿
• Respiratory distress
• Cough that doesn't go away

Serious complications are uncommon.

参考文献

勃洛克汉堡王. 胸腔穿刺术. In: 罗伯茨 JR, Custalow CB, Thomsen TW, eds. 罗伯茨 & Hedges' Clinical Procedures in Emergency Medicine and Acute Care. 7日艾德. Philadelphia, PA: Elsevier; 2019:chap 9.

Broaddus VC, Light RW. 胸腔积液. In: Broaddus VC, Ernst JD, King TE, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 7日艾德. Philadelphia, PA: Elsevier; 2022:chap 108.