A colleague in Rhode Island reports that at her blood center, manufacture of platelets, FFP and cryoprecipitate from a whole blood collection requires that the time from insertion of the needle to completion of the collection be no longer than 12 minutes. She is planning to change the limit to 15 minutes, as cited in the AABB Technical Manual. However, on investigating this issue she discovered that some blood centers currently use a maximum collection time of 20 minutes. She wonders if others would share their policy (time limit) and the scientific basis for deciding on this.

The following comments have been received.

ADDENDA June 8, 2004

1. A colleague in Spain reports that the Guide to the Preparation, Use and Quality Assurance of Blood Components published by of the Council of Europe, 10th edition, 2004 states:

"The flow of the blood must be sufficient and uninterrupted. Donation of a whole blood unit should ideally not last more than 10 minutes. If duration of the bleeding is longer than 12 minutes, the blood should not be used for the preparation of platelets. If the duration of the bleeding is longer than 15 minutes, the plasma should not be used for direct transfusion or the preparation of coagulation factors".

The Spaniard comments that by his reading, the Guide does not give any objective evidence to support the stated time limits. In his experience, low collection flow rates allow the coagulation cascade to activate in the needle and tubing and often some clots can appear in the blood bag. Thus, with long collections, one cannot be sure of the quality of the plasma or of the platelets. He concludes saying that such events are rare and his staff can increase extraction speed by stripping the tubing. He would not recommend extending the time limit over 15 minutes.

2. A transfusion medicine physician who practices in a small town in Central North Carolina reports that in his opinion there are really two related issues, the first involving donor comfort. In his experience, when a venous tourniquet is applied to an extremity, in a conscious individual the appendage becomes painful after about 20 minutes. Therefore, many blood centers choose to set an upper limit of 12 to 15 minutes to avoid a suboptimal donor experience that may dissuade a donor from returning for subsequent donations. In an unconscious individual, one can apply a tourniquet that stops blood flow from an artery for several hours, and the patient (because they are unconscious) does not experience the discomfort of this procedure. For example, this is how knee arthroplasties are performed in an essentially bloodless field. He continues that the second issue is associated with a slow flow of blood into the bag. If the flow is too slow, he believes that there may be delays in mixing of the whole blood with the anticoagulant and possible activation of the clotting cascades. It is this concern which forms the basis of saying "units requiring more than 15 minutes to draw may not be suitable for preparation of Platelets, Fresh Frozen Plasma, or Cryoprecipated AHF". With regards to colleagues who quote the Technical Manual as the authoritative source for how long the collection process should be, please note that the Technical Manual uses the word "may" (not shall), and it does not say that longer collection times would preclude the manufacture of such components. Thus, the North Carolinian argues that if longer collection times for donations have been validated in terms of quality of the resulting products, such donations should be acceptable.

ADDENDA June 10, 2004

3. A colleague in Southern California reports that at her blood center they use 17 minutes for the maximum allowable time for whole blood collection to allow for component manufacturing, and collect primarily in 500 mL containers. They increased the draw time from 15 to 17 minutes when they switched from 450 mL collections to 500 mL collections. The reason for lengthening the draw time was to accommodate the increased collection volume.

ADDENDA August 27, 2008

4. A Medical Director at a medium-sized blood center in Tennessee reports that her blood center manufactures red cells, random platelets, FP24, and cryoprecipitate from whole blood. They are considering increasing their collection time for whole blood donation to 15 minutes or more after reading the above discussion and based on the AABB Technical Manual (page 194, 16th Edition) which states: “A draw time longer than 15 to 20 minutes may not be suitable for platelets, or plasma, for transfusions.” She acknowledges being unable to find any literature that supports using a specific time limit for whole blood donation. She wonders if any centers that collect blood in 500 mL bags other than the one mentioned in the above discussion have adjusted their collection times to 15 minutes or longer? She also wonders if centers use red cells produced from products that exceed the maximum draw time that they’ve established, or if they merely limit the production of platelets and plasma from such collections? If so, she wonders what maximum draw time the centers use for red cell production?

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Ira A. Shulman, MD
CBBS e-Network Forum Editor & Moderator