Through the latest in automated technology, the American Red Cross now has the ability to collect two units of red blood cells from a single donor who meets all eligibility requirements. To ensure that a safe amount of blood is collected, all blood donations, whether Whole Blood or Apheresis procedures, have a minimum weight requirement. Roughly 220 milliliters of red cells are collected from Whole Blood donors and 360 milliliters of red cells are taken during a 2 unit red cell apheresis donation. To ensure that a 2 unit red cell donor has an adequate amount of red cells to safely participate in the donation procedure, more stringent height, weight, and iron requirements have been defined. While other factors play a part, the total amount of blood we have is primarily determined by our height and weight, also known as body mass.
Gender plays a role as well.
Recent studies with patients undergoing open-heart surgery show that even with similar heights and weights, women have lower blood volumes than men. Therefore, higher height and weight requirements were set for women to compensate for their lower blood volume and to ensure a safe blood donation. There are many advantages to the Double Red Cell collection program, both for the donor and for the patient. A double red cell donation takes about 45 minutes to complete, compared to about 10 minutes for a regular blood donation. However, the waiting period between donations is 16 weeks, rather than 8 weeks for a regular donation.