Cold finger after surgery indicates a reduced circulation to the finger. Rub the finger again and again, soak the finger in hot water, apply vapor rub to the finger to generate heat. If there is blood circulation, there will be heat. Also note the color of the finger. Is the color of the finger white, pale, pink, blue, or black?
Only pink indicates there is blood circulation. All other colors indicate lack of circulation, lack of heat, internal hemorrhage in the finger and a dying finger.