Friday April 14, 2006
A-line is here but where is Allen test !!
Its true that the usefulness of Allen test has never been tested in a big trial but it remained the recommended part before obtaining (radial) arterial blood gas or inserting (radial) arterial line as the whole concept makes common sense. But unfortunately, many times this is the most ignored part of whole procedure. Allen test was developed by legendary cardiologist from mayo clinic, Edgar Van Nuys Allen (1900 - 1961). He is well-known for his work on the administration of anti-coagulant, dicumerol to humans.
With the hand elevated and patient making fist (about 15 seconds), firm pressure applied against radial and ulnar arteries, which leads to blanching of the hand. Then, one of the arteries is released and, in the normal case the blanching disappears over the whole of the hand within 5 to 7 seconds. Test should be repeated with both arteries.
The New England Journal of Medicine has posted the free video on Placement of an Arterial Line (also demonstrating Allen test). Click here to see the link. (Volume 354:e13 - April 13, 2006)
1. Edgar Van Nuys Allen - whonamedit.com