The absence of a pulse at the elbow when the upper arm is tightened with a bandage is related to the fact that the blood flow in that area is affected. Pulse is also known as arterial beat, with the rhythmic contraction and diastole of the heart, the elbow arterial wall will correspondingly appear to dilate and retract, so the elbow arterial beat can be felt on the superficial arteries under the skin. Whereas the blood flow in the arterial vessels is from the heart to the extremities, when the upper arm is tightened with a bandage, the blood flow at the elbow is affected, and the blood passing through the elbow artery is reduced, with a lower amplitude of dilatation and retraction, so that the elbow pulse is not easily felt. Also, bulging veins in the forearms can usually be observed. Since the veins are the vessels that return blood from all parts of the body to the heart, tightening the upper arm with a bandage prevents blood from flowing towards the elbow and the venous valves prevent the blood from flowing back, which results in distended veins in the forearms, i.e., the “bruises” in the upper arm become more visible when the bandage is tightened. If you feel abnormal, it is recommended to go to the hospital for examination.