Allen Test

(A) Have the client rest the hand palm side up on the examination table and then make a fist. Use your thumbs to occlude the radial and ulnar arteries. (B) Continue pressure to keep both arteries occluded and have the client release the fist. Note that the palm remains pale. (C) Release the pressure on the ulnar artery and watch for color to return to the hand. To assess radial patency, repeat the procedure as before, but as the last step, release pressure on the radial artery.