The clinical effects of leukocyte removal filters, cellsavers and their combination on blood transfusion and organ damage during cardiac surgery.

Background:

Concern about adverse effects and costs of allogenic blood transfusions and concern about postoperative organ dysfunction, has increased the use of cell savers during cardiac surgery.
In a cell saver the wound blood is collected, washed, concentrated, and subsequently retransfused. However, the quality of this blood is not ideal. This may lead to organ dysfunction and even increased transfusions of blood products.
Recently, leukocyte depletion filters became available for clinical use. These filters not only remove leukocytes, but also fat and other particles. Transfusion of cell saver blood through a leukocyte filter may improve the quality and thus reduce blood transfusions and organ dysfunction. It is however, also possible that use of a leukocyte filter alone for the surgical wound blood has the same clinical effect as the combined procedure of washing and filtering. This would increase cost-effectiveness, as use of a cell saver is not necessary.




Aim of the study:

Does use of a cell saver combined with a leukocyte removal filter result in a decrease in transfusions of allogenic blood products and in organ dysfunction, compared to the use of a cell saver alone?
Is use of only leukocyte filters clinically as effective as the use of a cell saver with a leukocyte filter?




Study design:

Prospective randomized multicenter study in 600 cardiac surgical patients. To separate the effects of the cell saver and leukocyte removal filter, patients are divided in 4 groups.

1. In group I blood is processed with a cell saver and transfused.

2.. In group II blood is processed with a cell saver and transfused through a leukocyte filter.

3. In group III blood is only filtered with a leukocyte filter before transfusion.

4. In group IV blood will be transfused without filter and cell saver. This is standard care.




End points:

Primary end point for this study is: the number of allogenic blood products used.

Secondary end points are:

length of intensive care unit and hospital stay, renal and pulmonary dysfunction, markers of inflammation, and costs.





Interventions:

a. In group I and II, wound suction blood during the operation will be transferred to the cell saver instead of being wasted or returned to the heart lung machine as usual.
b. In group I, this processed blood will be transfused without additional filter.

c. In group II, this processed blood will be transfused through a leukocyte depletion filter.

d. In group III, the surgical wound suction blood will be collected in a separate cardiotomy reservoir and filtered with a leukocyte removal filter.

e. In group IV the wound suction blood during cardiopulmonary bypass and the residual blood from the heart lung machine will be transfused unfiltered, which is at this moment routine practice.

We hypothesize that the application of a leukocyte depletion filter for surgical wound blood will reduce organ damage and coagulation disorders through removal of activated leukocytes and other particles.
We expect that the efficacy of a cell saver combined with a leukocyte filter increases by reduction of allogenic blood transfusions and organ damage.

N/A

The patients will be divided in 4 groups according to a randomization table.

1. In group I (n= 150) blood will be processed with a cell saver and transfused without leukocyte removal filter;

2. In group II (n=150) blood will be processed with a cell saver and transfused through a leukocyte removal filter.

3. In group III (n=150) blood will be filtered with a leukocyte removal filter, but not be processed with a cell saver.

4. In group IV (n=150) blood will be transfused without filter and without cel saver.




In group I and II all the wound suction blood during the operation will be transferred to the cell saver instead of being wasted or returned to the heart lung machine as usual. In addition, the residual heart lung machine blood will be processed by the cell saver instead of being unprocessed transfused to the patient as usual.

In group I blood processed by the cell saver will be transfused without a leukocyte removal filter.

In group II blood processed by the cell saver will be transfused through a leukocyte removal filter.

In group III, the surgical wound suction blood before, during and after cardiopulmonary bypass and the residual heart lung machine blood will be collected in a separate cardiotomy reservoir and filtered with a leukocyte removal filter.

In group IV the wound suction blood before and after cardiopulmonary bypass will be discarded, which is at this moment routine practice. The wound suction blood during cardiopulmonary bypass and the residual blood from the heart lung machine will be transfused unfiltered, which is at this moment routine practice.