New Red Blood Cell Loss Limit for Platelet Donors

September 5, 2012 at 4:19 pm


A message from Dr. Susan Galel, Stanford Blood Center

If you are one of our dedicated platelet pheresis donors, you know that we keep careful records of how much you donate— and how often—in the familiar Annual Donor Records tucked in your chart. It is our responsibility to ensure that your donation frequency is safe for you. Before each of your donations, we tally all of your visits, red blood cell losses and plasma losses for the 12 months prior to that donation, to be sure that you will not exceed any of the safety limits.

Recently, the FDA standardized its method of calculating the maximum allowable red cell donation limit. By October 1, 2012, we will be lowering the allowable red blood cell loss from 1,620 to 1,430 mL in accordance with FDA’s new standardized formula. Plasma limits have not changed.

With each platelet donation, you lose a small amount of red blood cells in the plastic tubing of the pheresis circuit and in the tubes used for testing the donation. The red cell loss with each platelet donation (46 mL) is about one-quarter of the amount of red cells in a whole blood donation. If you donate platelets at the maximum frequency of 24 times per year, your annual red cell loss is quite high, but still within the new limit. Thus, we believe that most of our platelet donors will not be affected by the new FDA red cell limit calculation. If, however, you donate whole blood in addition to making platelet donations, your total red cell loss might exceed the new limit.

As you come in for your platelet donations over the next few months, we will be checking your red cell loss against the new limit. If you are close to or above the new limit, we will help you reschedule and adjust your visits to get you to the new limit by October. Within the prescribed limits, we will tailor collections with you to maximize the benefit to patients and the research community on the basis of your particular characteristics. Most importantly, we want to ensure your continued good health, comply with safety regulations, and keep you donating forever. If you have any questions about how this change might affect you, please ask your nurse the next time you donate.

If you are one of our “frequent flyers,” please know how much we respect and appreciate your commitment. Your efforts mean so much to patients in need, and their families. Thank you for being one of our invaluable donors!