Plethysmography

How the Test is Performed:
This test may be done in the health care provider's office or in a hospital. You are placed in a partially propped-up position. Then 3 blood pressure cuffs are wrapped snugly around the extremities. They are then inflated to 65 mmHg (millimeters mercury ), which increases the cuffs sensitivity to the pulse . The cuffs are then attached to a pulse volume recorder (plethysmograph) that displays each pulse wave. This pulse wave is also recorded on paper. Differences of the pulse waves in the 3 cuffs are noted. If there is a reduction in the wave, it may indicate a blockage. When the test, is complete the blood pressure cuffs are removed.

How to Prepare:
Refrain from smoking at least 30 minutes before the test. Remove all clothing from the extremities.

Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:



How it Feels:
There is no discomfort with this test. You will feel the cuff on the extremities.

Risks:
There are no risks associated with this test.

Why this Test is Performed:
The test is done to help rule out disease that blocks the arteries in the extremities.

Normal Values:
There will be less than 20 mmHg difference in the systolic blood pressure of the lower extremity compared to the upper extremity.

Abnormal Results:
Abnormal results may indicate arterial occlusive disease , trauma to the arteries, small vessel diabetic changes , blood clots , and vascular diseases.

Additional conditions under which the test may be performed:



Cost:
The estimated cost is $100.

Special Considerations:
The test is not as accurate as an arteriography. This may be done for seriously ill patients who cannot be transported to the arteriography laboratory.