Medically Reviewed By William C. Lloyd III, MD, FACS

What is aspiration?

Aspiration is the use of suction to remove fluid or other tissues from the body to test them for diseases and disorders. An aspiration can diagnose cancer, cysts, meningitis, abdominal infection, and complications of pregnancy. Your doctor may also use aspiration as a treatment to remove excessive or infected fluid in a joint or body cavity, such as the abdomen. 

Aspiration can be done in almost any body area or organ. It generally involves using a needle and syringe to withdraw the fluid or cells. 

Aspiration is only one method used to diagnose or treat some diseases and conditions. You may have less invasive testing or treatment options. Consider getting a second opinion about all of your choices before having an aspiration.

Types of aspiration

Common types of aspiration include:

  • Abdominal tap (abdominal paracentesis) is the removal of fluid from the space around the abdomen. An abdominal tap can find the reason for fluid buildup (ascites) and drain excessive fluid. An abdominal tap can also diagnose infection (peritonitis) and bleeding due to trauma.

  • Amniocentesis is the removal of amniotic fluid from a pregnant uterus. It can diagnose certain fetal or uterine conditions. These include blood type incompatibility between the fetus and mother, infections, genetic abnormalities, and a low or excessive amount of amniotic fluid. It can also determine if a baby’s lungs are developed enough for birth.

  • Arthrocentesis is the removal of synovial fluid from a joint. It can determine the cause of swelling (effusion). Arthrocentesis may also treat relieve joint pain by injecting medications or removing excessive or infected fluid from a joint.

  • Aspiration of a lump, cyst, tumor or mass can be performed in most organs and body areas to test for infection, cancer, or other problems. Examples include the breast, liver, neck or pancreas. Drainage of the fluid from a cyst is a common example of aspiration treatment.

  • Bone marrow aspiration and biopsy is the removal of bone marrow from the inside of a bone. It can test the production of healthy red blood cells. It may be ordered to help diagnose leukemia and other cancers and evaluate cancer treatment. Bone marrow aspiration and biopsy can also diagnose certain chromosomal abnormalities and the cause of low blood counts or fever.

  • Lumbar puncture (spinal tap) is the removal of fluid from the spine. It can test for infections and inflammatory diseases of the spine and nervous system. Lumbar puncture can also be used to inject certain medications, such as antibiotics and chemotherapy.

  • Thoracentesis (pleural tap) is the removal of fluid from the space around the lungs. It is used to find the reason for fluid buildup in this area (pleural effusion). It can drain excessive fluid to make breathing easier. Thoracentesis can also diagnose an infection in the lung space (empyema).

Other procedures that may be performed

Your doctor may perform other procedures in addition to aspiration. These include:

  • Medication injection, which involves injecting medication, such as an anesthetic or a steroid, into the aspirated area, often a joint. This can help relieve pain or swelling and inflammation.

  • Tissue biopsy, which involves testing the removed fluid or other tissues for infection, malignancy (cancer), and other disease.

Why is aspiration performed? 

Your doctor may recommend an aspiration to diagnose and possibly treat the following diseases and conditions:

  • Abdominal conditions, such as abdominal trauma, abdominal infection (peritonitis), and cancer or liver disease that leads to ascites (fluid buildup in the abdomen)

  • Bone marrow conditions, such as leukemia and metastasis (spread) of a variety of cancers, certain chromosomal abnormalities, and low blood count or fever that has not been diagnosed with less invasive testing

  • Brain and spinal cord conditions, such as a meningitis, multiple sclerosis, and cancer 

  • Joint conditions, such as arthritis, gout, joint injury, inflammation or infection of a joint, and joint effusion (accumulation of fluid in the joint)

  • Lumps, cysts, tumors or masses. Aspiration is used to diagnose and possibly treat these conditions.

  • Lung conditions, such as fluid buildup in the space around the lungs (pleural effusion) and infection in the lung space (empyema)

  • Pregnancy and fetal conditions, such as fetal or uterine infection, genetic abnormalities, and a low amount of amniotic fluid. Other conditions include fetal anemia due to Rh incompatibility (incompatibility of the mother and baby’s blood types) or to determine if a baby’s lungs are developed enough for premature delivery.

Ask your doctor about all of your testing or treatment options and consider getting a second opinion before deciding on an aspiration.

Who performs aspiration?

The type of doctor who performs your aspiration will vary based on the type of aspiration. Following is a partial list of specialists who perform aspirations:

  • General surgeons specialize in the surgical care of diseases, injuries and deformities affecting the abdomen, breasts, digestive tract, endocrine system and skin.

  • Infectious disease specialists are internists or pediatricians who have additional training in the diagnosis and treatment of infectious diseases.

  • Obstetrician and gynecologists (Ob/Gyns) specialize in women's health, pregnancy, and labor and delivery.

  • Oncologists are internal medicine doctors or pediatricians who have specialized training in treating cancer.

  • Orthopedic surgeons specialize in the surgical treatment of diseases of the bones and connective tissues.

  • Pulmonologists are internists or pediatricians with specialized training in treating diseases and conditions of the chest. They include pneumonia, asthma, tuberculosis, emphysema, or complicated chest infections.

  • Radiologists are physicians that are trained to utilize imaging, such as ultrasound to guide aspirations.

How is aspiration performed?

You aspiration will be performed in a doctor's office, outpatient setting, or hospital, depending on the type of aspiration and your condition.

Doctors usually use a local anesthesia to numb the area during aspiration. This is a type of nerve block. It involves injecting an anesthetic using a tiny needle in the skin and tissues around the procedure area.  This numbs (blocks) a small area around the procedure site. 

Aspiration can also be part of a surgery using general anesthesia, which puts you in a deep sleep.

Commonly performed aspiration procedures generally include these steps:

  1. You will remove your clothing and possibly dress in a patient gown.

  2. You will be lie on the examination table to allow access to the aspiration site. 

  3. In some cases, your doctor will sedate you to make you drowsy and relaxed. Your team will monitor your vital signs in this case. You may also have a pain medication.

  4. Your doctor will clean and numb the aspiration site.

  5. Your doctor will insert a needle into the appropriate area. Insertion of the biopsy needle may be guided by imaging technology, such as ultrasound or CT scan.

  6. Your doctor will withdraw a small amount of fluid or tissue into a syringe for testing. Excessive fluid is withdrawn with a large syringe or a device attached to the needle.

  7. Your doctor will detach the syringe full of fluid from the needle and replace it with a syringe of medication to inject, if needed.

  8. Your doctor will remove the needle and clean and bandage the area.

  9. Your doctor will send the fluid or tissue sample to the laboratory for evaluation.

  10. Your doctor may leave a drain where the needle was placed to continue draining fluid. Your doctor will discuss this with you before the procedure.

Will I feel pain?

Your comfort and relaxation is important to you and your care team. You may feel a pinch, discomfort or stinging when the area is numbed and pressure during the procedure. Your doctor will give you pain and sedative medications as needed so that you stay comfortable. Tell you care team if you are uncomfortable in any way.

What are the risks and potential complications of aspiration?  

Complications of aspiration are uncommon but can occur and may become serious in some cases. Complications can develop during the procedure or recovery. 

Complications of aspiration are not common but include: 

  • Adverse reaction or problems related to sedation or medications, such as an allergic reaction and problems with breathing

  • Bleeding

  • Headache after a lumbar puncture

  • Hypotension (low blood pressure) if a large amount of fluid is removed

  • Infection

  • Nerve injury

  • Pneumothorax (air in the space around the lung that can collapse the lung) from a thoracentesis 

  • Pregnancy complications after amniocentesis, such as miscarriage, amniotic fluid leaking, or injury or infection to the baby

  • Re-accumulation of fluid when excessive fluid is withdrawn for a treatment 

  • Return of pain or worsening pain

Reducing your risk of complications

You can reduce the risk of some complications by following your treatment plan and: 

  • Following activity, dietary and lifestyle restrictions and recommendations

  • Informing your doctor or radiologist if you are nursing or there is any possibility of pregnancy

  • Notifying your doctor immediately of any concerns, such as bleeding, fever, or increase in pain

  • Taking your medications exactly as directed 

  • Telling all members of your care team if you have any allergies

How do I prepare for my aspiration?

You are an important member of your own healthcare team. The steps you take before your aspiration can improve your comfort and outcome. 

You can prepare for an aspiration procedure by:

  • Answering all questions about your medical history and medications. This includes prescriptions, over-the-counter drugs, herbal treatments, and vitamins. It is a good idea to carry a current list of your medical conditions, medications, and allergies at all times.

  • Learning about the procedure and asking any questions you may have

  • Taking or stopping medications exactly as directed. This may include not taking aspirin, ibuprofen (Advil, Motrin), and blood thinners.

Questions to ask your doctor

Having an aspiration can be stressful. It is common for patients to forget some of their questions during a brief doctor’s office visit. You may also think of other questions after your appointment. Contact your doctor with concerns and questions before your aspiration and between appointments.

It is also a good idea to bring a list of questions to your appointment. Common questions include:

  • Why do I need aspiration? Are there any other options for diagnosing or treating my condition?

  • How long will the procedure take? When can I go home?

  • What restrictions will I have after the procedure? When can I expect to return to work and other activities?

  • What kind of assistance will I need at home? Will I need a ride home?

  • How should I take my medications? 

  • How will you manage my pain?

  • When and how will I get my test results?

  • What other tests might I need?

  • When should I follow-up with you?

  • How should I contact you? Ask for numbers to call during and after regular hours.

What can I expect after my aspiration?

Knowing what to expect after aspiration can help you get back to your everyday life as soon as possible.

How will I feel after the aspiration?

You might feel a little drowsy if you had sedative and pain medications. You may have mild soreness, tenderness or pain after the procedure. 

Take pain medications, such as acetaminophen (Tylenol) or nonsteroidal anti-inflammatory drugs (NSAIDs), only as directed by your doctor. Some people with certain conditions should not take NSAIDs. Your doctor will give you specific instructions based on the type of aspiration and your condition.

When can I go home?

You will go home right away after an outpatient aspiration. You will need to stay in the outpatient facility or hospital for a short period of time if you had sedation or pain medication. You will be discharged home when you are alert, breathing effectively, and your other vital signs are stable. This generally takes less than an hour.

You should not drive for about 24 hours after sedation and will need a ride home because you will still be drowsy. Someone should stay with you for the first day or so.

When should I call my doctor?

It is important to keep your follow-up appointments after an aspiration.  Call your doctor if you have any concerns including:

  • Bleeding, including vaginal bleeding after an amniocentesis
  • Drainage from the site or leakage of fluid from the vagina after an amniocentesis
  • Fever (you should not have any fever after aspiration)
  • New or unexplained symptoms
  • Pain that is not controlled by your pain medication, new pain, or increase in pain
  • Rash or skin irritation
  • Swelling, warmth or redness over the aspiration site
Was this helpful?
  1. Amniocentesis. American Pregnancy Association.
  2. Bone Marrow Aspiration and Biopsy. Lab Tests Online.
  3. Arthrocentesis. Memorial Sloan-Kettering Cancer Center.
  4. Evaluating postoperative fever: A focused approach. Cleveland Clinic Journal of Medicine.
  5. Knee Joint Aspiration and Injection. American Academy of Family Physicians.
  6. Lumbar Puncture. The New England Journal of Medicine.
  7. Paracentesis. The New England Journal of Medicine.
  8. What is Thoracentesis? National Heart Lung and Blood Institute.
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Nov 23
View All Tests and Procedures Articles
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.