Allen’s Test for Collateral Circulation For the Allen test, you apply pressure to the radial and ulnar arteries in your wrist for several seconds. This will stop the blood flow to your hand, and your hand will become cool and pale. Then one artery is released. Normal- normal return of color. The one artery alone can supply blood to your fingers and hands. Abnormal- hand remains cold and pale. This means there is not enough flow from the one artery to supply blood to your fingers and hands. #Allens #Test #Collateral #Circulation #Radial #Ulnar #Perfusion #Diagnosis #PhysicalExam #Vascular
