MODEL RELEASED. Blood pressure measurement. Woman's blood pressure being taken by a nurse before blood platelet donation. The nurse is using a stethoscope to listen to her blood flow. The cuff on the woman's arm is inflated until it stops the blood flow, then released. A sphygmomanometer initially reads her systolic blood pressure. Her diastolic pressure is taken after the flow has fully resumed. This woman is about to undergo apheresis: her blood will be collected and separated. The red blood cells will be returned to her, whilst the platelets (important for blood clotting) will be donated to leukaemia patients, who lack them.