THE SEARCH FOR A CLINICALLY USEFUL BLOOD SUBSTITUTE

Through the years, researchers and corporations have sought to develop a clinically useful blood substitute. Applications of a blood substitute are numerous. Short-term support applications include intravascular resuscitation following trauma, media for hemodilution on the elective surgery patient, transfusions for patients with red cell incompatibilities, and use in patients with ischemic vascular disease or who require coronary angioplasty. Key criteria include the substitute's ability to maintain intravascular volume and solute equilibrium and to carry oxygen and carbon dioxide. Major categories of blood substitutes include perfluorocarbon solutions, lyophilized or ''instant'' red cells, hemoglobin-based compounds, and neohematocytes. This is the second article in a four-part continuing education series on blood banking. Other articles focus on ensuring quality during intraoperative blood salvage, electronic cross-match, and transfusion triggers.