Pre-Autologous Donation (PAD)

From Noblood

Preoperative autologous donation is a process by which your own blood is collected, stored and re-infused during surgery. Storage and collection is conducted either at an in-hospital location or a local Canada Blood Systems [CBS] site. You will typically donate 2 to 4 units of your own blood, beginning no more than 4 weeks prior to scheduled surgery. You must qualify to donate your own blood, and there are existing criteria for inclusion in a PAD program. PAD units may be stored up to 35 days, but this may vary in your hospital or health care region.

Oxygen delivery is maintained during hemodilution by increased cardiac output and oxygen delivery. Blood flow through capillary beds is maximal at a hematocrit of 30% and, as noted previously, physiologic adverse effects are minimal. Hemodilution to a hematocrit of 20% is considered extreme hemodilution and is restricted to young patients with no physiologic compromise.

Advantages of acute normovolemic hemodilution include the immediate availability of fresh blood with normal levels of clotting factors, avoidance of the infectious risks of allogeneic stored blood, reduced cost in the processing of the collected units, and avoidance of administrative errors that can lead to hemolytic reactions, even with the use of preoperatively collected autologous units of blood. Unexpected blood loss during the operative procedure may result in hypovolemia, a fall in cardiac output, and physiologic decompensation. This condition is exacerbated with extreme hemodilution.