Fat removal during cell salvage: a comparison of four different cell salvage devices.

Background: Fat embolism is a possible risk factor for pulmonic and cerebral dysfunction after orthopedic and heart surgery. It is unknown whether fat occasionally observed during cell salvage adds to the risk of fat embolism after retransfusion. We have examined the fat removal capacities of different cell salvage devices including discontinuous and a continuous system under various conditions.

Study Design And Methods: In an experimental study ABO-matched banked blood was adjusted to a hematocrit of 20%, and 1.25% of human fat was added. This blood was processed with the cell salvage devices XTRA and Electa, CATS, or Cell Saver 5 plus. Fat in the blood samples was quantified by volumetric measurement after centrifugation in Pasteur pipettes and by gravimetric measurement after extraction of fat in organic solvents and phase partition. Performance in fat removal was tested with different programs, bowl sizes, and additional filtration.

Results: The continuous system consistently showed a high fat removal rate of 99.8 ± 0.2%. Fat accumulated in the wash disposal, but not in the product. In the Latham bowl-based discontinuous systems, fat removal varied from 69.2 to 92.8 ± 4.4% depending on the program mode, but not on the bowl size. Additional filtration increased fat removal to 96.7 ± 2.2%, but also increased red blood cell loss.

Conclusions: Fat contamination of wound blood can be detected by volumetric and gravimetric measurements. Continuous salvage systems remove fat to a higher extent than discontinuous systems. The fat removal capacities of discontinuous systems depend on the program mode and can be improved by filtration.