Non-pharmacological strategies for blood conservation in cardiac surgery.

PURPOSE

Of all surgical specialties, cardiac operations are most often associated with coagulopathy, blood loss, and the need for transfusions. This not only represents a major burden on blood procurement and banking organizations at all levels, but also constitutes a risk for each patient receiving allogeneic blood products. This paper reviews current non-pharmacological strategies aimed at decreasing blood use in patients undergoing cardiac surgery.

SOURCE

The literature pertaining to each blood conservation strategy was searched, reviewed, and appraised. Meta- analyses were also consulted and their results complemented with subsequent reports when available.

PRINCIPAL FINDINGS

Preoperative autologous donation programs are effective in decreasing allogeneic transfusions, but are costly and applicable to elective patients only. Off-pump revascularization strategies also appear to decrease transfusion requirements in suitable patients. The effectiveness of acute normovolemic hemodilution, retrograde autologous priming, small volume cardiopulmonary bypass circuits, platelet-rich plasmapheresis, alternative heparin strategies, and postoperative cell salvage are more difficult to appraise as a high proportion of available studies suffer from lack of transfusion guidelines or the absence of blinding. Biological glues, surgical adhesives, and postoperative increases in positive end-expiratory pressure (PEEP) have no demonstrated efficacy.

CONCLUSION

The applicability or effectiveness of many of these modalities remains controversial and more studies are needed before they may be employed routinely in cardiac surgical patients. The judicious use of rational transfusion guidelines may still be the simplest and most cost-effective means of blood conservation today.