SDP-Single Donor Platelet are preffered. -In this process whole bloodis drawn from one arm into a sterile kit inside a cell separating machine. -The machine separates the bloodso that onlyplateletsand plasma are collected. -The other bloodcomponents (red cells and white cells) are returned to thedonor the same arm. -Because we want the blood to flow in the proper way, so we will do addition of anti-coagulant solution like citrate based anti-coagulant. -This anti-coagulant solution will not only prevent clot formation but will also cause decrease in the concentration of ionized Ca2+ - causing transient hypocalcemia which will lead to Perioral tingling and numbness. To prevent this condition from happening we prescribe oral calcium supplementation to the respective patient or we reduce the flow of device through which the blood is supposed to pass.