Fluid Aspiration

Fluid aspiration is a minor surgical procedure that can be used for diagnostic or treatment purposes. It involves the use of an instrument known as an aspirator, consisting of a needle and syringe, to remove abnormal fluid that has accumulated in any area of the body.

Reasons for Fluid Aspiration

There are a variety of reasons for fluid to be aspirated both for drainage and diagnostic purposes.

Joint Aspiration

Joint aspiration is a common procedure. It is performed to alleviate pain and reduce swelling due to tendonitis, bursitis, arthritis, joint infections or gout.

Aspiration of Pleural Effusion, Empyema, or Lung Abscess

Fluid or pus may accumulate in the lungs because of an infection, a disease, a foreign substance, or a blockage. When fluid accumulates in the lungs it is called pleural effusion. When pus accumulates in may be evidence of a lung abscess or an empyema, a collection of pus in the pleural cavity. Any of these conditions may result in breathing difficulties. Aspiration of fluid from the lungs can not only relieve symptoms temporarily, but also provides material for laboratory analysis of possible pathogens or malignancies.


Aspiration of amniotic fluid during pregnancy aids in determining certain fetal abnormalities. Because there are risks associated with this procedure, it is usually performed only when there is a perceived risk factor such as an abnormal ultrasound, a family history of birth defects or when the expectant mother is older than 35 years of age. Amniocentesis is helpful in diagnosing the following conditions in the fetus:

  • Down syndrome
  • Sickle cell disease
  • Cystic fibrosis
  • Muscular dystrophy
  • Tay-Sachs
  • Spina bifida
  • Anencephaly

Cyst or Tumor Aspiration

Fluid aspiration is an excellent diagnostic tool that may be used to drain cysts or tumors anywhere in the body. Cysts are sacs which may fill with excess fluid. Tumors, which are abnormal masses of tissue, may also be aspirated to determine whether they are malignant or benign.

Bone Marrow Aspiration

Bone marrow is examined through the use of fluid aspiration when a blood disorder is suspected. The laboratory examination of the fluid removed will help to diagnose and discover the cause of blood disorders, such as anemia, or to detect blood cancers, such as leukemia.

Aspiration During Surgery

Sometimes excessive blood or other fluid accumulates during a surgical procedure and becomes intrusive in the surgery itself. Fluid aspiration can remove the excess liquid at the site to help clear the region for increased visibility and precision.

Spinal Tap

At times, it is necessary for physicians to examine spinal fluid in which case the patient must undergo a spinal tap. This procedure is used to diagnose various spinal, neurological and brain disorders, such as meningitis and multiple sclerosis.

Abdominal Tap

In some cases, fluid aspiration from the abdominal cavity is necessary even when surgery is not being performed. When a patient suffers an abdominal trauma or an infection of the area, such as peritonitis, an abdominal tap may be performed.

When a patient develops a fluid buildup in the abdomen, known as ascites, abdominal fluid is often examined to determine whether the cause of the fluid accumulation is cancer or liver disease.

The Fluid Aspiration Procedure

Fluid aspiration, though a simple procedure, is an important one. It assists in the diagnosis of a great variety of illnesses, providing fluid for laboratory analysis. In addition, fluid aspiration can clear excess blood or other fluid during surgery and remove fluids which accumulate as part of disease processes or injuries, expediting the healing process. Fluid aspiration is usually performed under the guidance of diagnostic imaging such as X-ray or ultrasound to ensure precise placement of the needle. For most patients, only a local anesthetic is needed to minimize discomfort.

This procedure is effective in relieving symptoms caused by abnormal fluid collections, such as in empyemas or abdominal abscesses. Once the fluid is removed, it is sent to a laboratory for analysis. When the pathology results are returned, patient and doctor can discuss any necessary treatment options. Fluid aspiration is a safe procedure as long as it is performed by an experienced radiologist and sterile needles are used.

Risks of Fluid Aspiration

Fluid aspiration is a very safe procedure as long as it is performed under sterile conditions. As with any medical intervention, there is some element of risk. Bruising, swelling or discomfort at the aspiration site are not uncommon. More rarely, an infection at the site may occur.

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