What is Ventilation–Perfusion Scan

Ventilation perfusion scan is a procedure to look at airflow and blood flow in the lungs. It is most often done to look for a blood clot that may have traveled to the lungs (pulmonary embolus).

During this scan, radioactive compounds are injected into the bloodstream and are also breathed in. The compounds are not harmful. They are given at very low doses and stay in the body for a short time. After the compounds are injected and breathed in, a camera is used to scan the lungs.

Tell a health care provider about:

• Any allergies you have.
• All medicines you are taking, including vitamins, herbs, eye drops, creams, and over-the-counter medicines.
• Any blood disorders you have.
• Any surgeries you have had.
• Any medical conditions you have.
• Whether you are pregnant or may be pregnant.
• Whether or not you are breastfeeding.

What are the risks?

Generally, this is a safe procedure. However, problems may occur, including an allergic reaction to the radioactive compounds.

What happens before the procedure?

• Do not use any products that contain nicotine or tobacco, such as cigarettes and e-cigarettes. If you need help quitting, ask your health care provider.
• Take over-the-counter and prescription medicines only as told by your health care provider.

What happens during the procedure?

• An IV will be inserted into one of your veins. The IV will stay in place for the entire exam.
• A small amount of radioactive material will be injected into your bloodstream.
• Your lungs will be scanned with a camera. This camera will record the images.
• You will be asked to inhale a second radioactive compound. Take deep breaths as directed by the health care provider.
• Your lungs will be scanned again.
• Your IV will be removed.

The procedure may vary among health care providers and hospitals.

What happens after the procedure?

• You may go home unless your health care provider instructs you differently.
• You may continue with your normal activities and diet as instructed by your health care provider.
• It is up to you to get the results of your procedure. Ask your health care provider, or the department that is doing the procedure, when your results will be ready.

Summary

• A ventilation–perfusion scan is a scan to look at airflow and blood flow in the lungs. It is most often done to look for blood clots that may have traveled to the lungs.
• The radioactive compounds are not harmful.
• Your lungs will be scanned with a camera. This camera will record the images.
• It is up to you to get the results of your procedure. Ask your health care provider, or the department that is doing the procedure, when your results will be ready.