Perioperative red cell salvage: a case for implementing the 1995 consensus statement

Are cell salvage and autologous blood transfusion safe in endonasal surgery?

OBJECTIVE

Endoscopic transnasal approaches to the skull base and intracranial disease are an emerging subspecialty. The limits of this approach are often dictated by exposure and blood loss. Cell salvage techniques are widely used in other surgical fields. However, in otolaryngology, questions remain regarding its safety because work is performed in a contaminated field. In this literature review, we present the evidence for perioperative cell saver blood transfusion in potentially contaminated fields and the need for further investigation of its use in endonasal surgery.

DATA SOURCES

MEDLINE and Evidence Based Medicine Reviews databases were searched for relevant articles.

REVIEW METHODS

All English articles discussing autologous blood transfusion in endonasal surgery were reviewed.

RESULTS

Despite a wide search pattern, no articles that discuss this topic were found in the English literature. Therefore, we went on to present data on the general use of cell saver blood in contaminated fields.

CONCLUSION

Cell saver blood is widely accepted in surgery. It offers many advantages in elective operations in which blood loss is expected to be significant. Cell saver blood has been transfused from contaminated fields in other forms of surgery without an associated increase in morbidity. There is good evidence that antibiotic prophylaxis is mandatory in this setting. There is no direct evidence that cell salvage blood is safe in endonasal surgery. Cell salvage is part of a multimodality approach, including the use of hypotensive anesthesia, topical procoagulants, a dedicated team with appropriate equipment, and a good surgical technique with a focus on hemostasis.

Biochemical stabilization enhances red blood cell recovery and stability following cryopreservation

Glycerolized red blood cells (RBC) are approved for long-term cryopreservation. However, the need to remove the glycerol cryoprotectant prior to transfusion has limited the usefulness of this cryopreservation method. This report describes using non-cryoprotectant biochemical stabilization techniques to substitute for the standard glycerol cryoprotectant. The glycerolized RBC method was compared to a newly developed LC-V method that combines transfusable cryoprotectants (hydroxyethyl starch and dextran) and specific non-cryoprotectant biochemical stabilizers (nicotinamide, nifedipine, and flurbiprofen). Results demonstrate that the biochemical stabilizers significantly reduce cryopreservation-induced hemolysis compared to cryopreservation in their absence and that thaw hemolysis levels approach those of standard 40% (w/v) glycerolized RBC (3.1+/-0.2% for 40% glycerol compared to 8.7+/-0.9% for the LC-V protocol). Furthermore, LC-V cryopreserved RBC exhibit a significantly enhanced post-thaw stability compared to glycerolized RBC as determined by osmotic fragility index (0.557+/-0.034 for 40% glycerol compared to 0.478+/-0.016 for the LC-V protocol). Analysis of biochemically stabilized RBC proteins revealed a transient translocation of carbonic anhydrase to the membrane fraction. However, the enhanced RBC recovery and stability could not be attributed to this event. Finally, DSC analysis demonstrated that the biochemical stabilizers of the LC-V process were not functioning as surrogate cryoprotectants in that they did not affect the quantity or quality of ice formed. Overall, this work demonstrates that cryopreservation-induced RBC damage may be corrected or prevented through specific biochemical stabilization and represents a significant step toward a directly transfusable cryopreserved RBC product.

Autologous transfusion and other approaches to reduce allogeneic blood exposure

When used as the sole source of transfused blood, the principal advantage of autologous blood transfusion is the avoidance of transmission of infectious agents and the avoidance of the purported adverse immunomodulatory effects of allogeneic transfusion. In the 1990s, however, the risks of transfusion-transmitted diseases have been greatly reduced, and estimates of the cost-effectiveness of pre-operative autologous blood donations now vary between 2470 dollars and 3,400,000 dollars per quality-adjusted year of life saved, depending on assumptions about the existence and magnitude of any adverse immunomodulatory effects of allogeneic transfusion. There is a paucity of randomized controlled trials evaluating the clinical outcomes and the cost-effectiveness of autologous transfusion procedures, and this situation is unlikely to change in the near future because of the difficulties in conducting such trials. This chapter reviews the available evidence on the efficacy, safety and cost-effectiveness of the three common autologous transfusion procedures, that is, pre-operative autologous blood donation, acute normovolaemic haemodilution, and intra-operative and post-operative blood recovery.