Why is the modified Allen test performed?
USE THE MODIFIED Allen test to assess the integrity of the ulnar artery before your patient undergoes radial artery puncture or cannulation. You must verify ulnar collateral circulation to ensure blood flow to the hand if embolization or a thrombus occludes the radial artery.
What does a positive modified Allen test look like?
Positive modified Allen test – If the hand flushes within 5-15 seconds it indicates that the ulnar artery has good blood flow; this normal flushing of the hand is considered to be a positive test.
What is the difference between Allen test and modified Allen test?
The modified Allen test differs from the original Allen test mainly by examining the radial and/or ulnar arteries in one hand and then repeating on the other side, if necessary. Traditionally, it is performed by first having the patient’s arm flexed at the elbow with the fist clenched tightly to exsanguinate the hand.
The modified Allen’s test is also performed prior to heart bypass surgery. The radial artery is occasionally used as a conduit for bypass surgery, and its patency lasts longer in comparison to the saphenous veins. Prior to heart bypass surgery, the test is performed to assess the suitability of the radial artery to be used as a conduit.
What is a mod Allen test?
Arteries of the hand. In medicine, Allen’s test or the Allen test is a medical sign used in physical examination of arterial blood flow to the hands. It was named for Edgar Van Nuys Allen, who described the original version of the test in 1929.
How to perform Allen test?
To perform an Allen’s test: The patient’s hand should be elevated above his or her heart; The patient’s should be asked to make a fist; Pressure should be applied to both the radial and the ulnar artery until distal blood flow is occluded;
What is the Allen test procedure?
Allen test Procedure. The procedure for performing a modified Allen’s Test is as follows: Instruct the patient to clench his or her fist; if the patient is unable to do this, close the person’s hand tightly. Using your fingers, apply occlusive pressure to both the ulnar and radial arteries, to obstruct blood flow to the hand.
