Your physician has suggested you have a test to assess the small blood vessels in your feet and legs. There are two different tests that can do this; Skin Perfusion Pressure Test (SPP) and Transcutaneous Oximetry Test (TcPO2).
These tests will assess if these tiny blood vessels are blocked or damaged, or if the wound is getting enough blood to heal. Blocked or damaged blood vessels may keep your wound from healing.
Why do I need these tests?
Oxygen is needed for wounds to heal. Blood vessels and tiny blood vessels called capillaries carry oxygen to the wounds. Blocked or damaged blood vessels may decrease blood to the wounds. Wounds that do not get enough blood may not heal.
Your physician will determine which test is best for you.
How is the SPP test done?
During the SPP test you will lie flat. A small sensor is placed near the wound. Then a blood pressure cuff is placed over the sensor.
The test determines how much blood is flowing around the test site.
The SPP test takes approximately 5-10 minutes to perform at each site. You may need more than one site evaluated.
How is the TcPO2 test done?
The TcPO2 test is painless and can be done two different ways. For both tests small sensors are placed around the wound. The sensors measure the amount of oxygen getting to the wounds. The sensors can get warm. The sensors can leave a reddened area for a short time.
For one method you simply lie in a regular room to have the test done. This will tell us how much oxygen is in the tissues under normal conditions. This test takes about 45 minutes to complete.
The other method is done at a higher pressure. To get higher pressure the test is done in a hyperbaric chamber. While you are in the chamber you breathe 100% oxygen.
This TcPO2 test tells us the how much extra oxygen gets to the wounds. This will tell us if your wound might improve with hyperbaric oxygen therapy. The test usually takes 2 ½ hours to complete.
Your physician will determine which TcPO2 test is best for you.
Pre-test instructions for both tests:
- Do not smoke for 2 hours before the test.
- Do not drink caffeine after midnight the night before the test.
- Remain as still as possible during the test.
- Do not talk, eat or drink during the test.
- For TcPO2 in the hyperbaric chamber there are more instructions. Those special instructions will be reviewed with you.
What happens after the tests?
The sensors and blood pressure cuffs, if used, will be removed. A dressing will be applied if needed. There are no side effects of the test. Your physician will review the results with you.