A colleague in Barcelona reports that a blood component preparation laboratory at a large blood center in Catalonia, Spain processes about 140,000 units annually. Whole blood units are leukocyte-reduced by filtration prior to centrifugation and separation of components. The filtration process results in a small quantity of air getting into the component bag. The Barcelona colleague reports that this air is sterile, because it originates from the leukocyte reduction filter and attached tubing, and is not introduced into the product as a consequence of a breach in the hermetic seal. In order to remove this air a technician must squeeze the bag manually, and this effort causes pain in the hands of the technicians. The Barcelona colleague wonders if others have a similar experience and if so, how do they deal with it to prevent pain for the staff?

The following responses have been received.

ADDENDA Oct. 11, 2003

1. A female colleague and Blood Bank Technical Services Q.A./Training Coordinator at a blood center in the USA reports that being a woman, she had the same problem with her hands hurting when leukoreducing a large quanity of units. She states: "I simply started using our component plasma expressors. The old models with the handle in the front worked the best. I was able to tip the unit in the expressor, allowing all the air to flow out of the bag. This took a little extra time with only one person, but it works great with two people. I just let the expressor do the work for me."

2. Editor's Note: It is interesting that at least two different blood centers in two different countries report that during the process of leukocyte reduction filtration, air may be introduced into a blood product container, and that the introduced air must be expressed from the blood container as part of the leukocyte reduction process. The Editor is interested to learn if it is a common occurrence for air to be introduced into blood products that are being filtered to reduce their leukocyte content. The Editor is under the impression that it has been established that an air interface may promote damage to red blood cells. If that impression is true, one must wonder about the effect that the introduction of air might have into a whole blood or RBC unit during a leukocyte reduction procedure, and if the introduced air has the potential to damage some of the red blood cells in the product and result in demonstrable hemolysis. The potential impact of an air-blood interface might be worth considering when troubleshooting hemolyzed leukocyte reduced blood products. The discussion "Troubleshooting a problem with hemolyzed units of leukoreduced RBCs" might be worth reading with this consideration in mind.

ADDENDA Oct. 14, 2003

3. The Barcelona colleague adds the following, in response to the comments of the female colleague from USA (#1 above). They already implement a manual system like the one mentioned by the USA colleague, and their plasma expressors with a handle in front worked well. However, the process is not as fast as they need for the number of units they must process.

The Barcelona colleague wishes to call attention to a new whole blood filtration system that appears in the September issue of Transfusion (last page). The Barcelona colleague concludes that the manufacturer appears to have addressed the need for manually squeezing the blood bag.

ADDENDA Oct. 16, 2003

4. The colleague from Barcelona adds the following additional information. They do not know if the blood/gas interface can damage red cells when they process their whole blood into leukocyte-reduced products. In their center, they introduced universal leukoreduction in December 2001. They report that they initially observed some units with hemolysis upon beginning their universal leukoreduction protocol. However, this problem seemed to go away when they changed their procedure to keep the blood bag resting on a flat surface, rather then suspending the bag by gravity. They agree with comments in the forum issue titled "Troubleshooting a problem with hemolyzed RBCs".

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