Volume replacement can be accomplished without using whole blood or blood plasma.a Various nonblood fluids are effective volume expanders. The simplest is saline (salt) solution, which is both inexpensive and compatible with our blood. There are also fluids with special properties, such as dextran, Haemaccel, and lactated Ringer’s solution. Hetastarch (HES) is a newer volume expander, and “it can be safely recommended for those [burn] patients who object to blood products.” (Journal of Burn Care & Rehabilitation, January/February 1989) Such fluids have definite advantages. “Crystalloid solutions [such as normal saline and lactated Ringer’s solution], Dextran and HES are relatively nontoxic and inexpensive, readily available, can be stored at room temperature, require no compatibility testing and are free of the risk of transfusion-transmitted disease.”—Blood Transfusion Therapy—A Physician’s Handbook, 1989.

You may ask, though, ‘Why do nonblood replacement fluids work well, since I need red cells to get oxygen throughout my body?’ As mentioned, you have oxygen-carrying reserves. If you lose blood, marvelous compensatory mechanisms start up. Your heart pumps more blood with each beat. Since the lost blood was replaced with a suitable fluid, the now diluted blood flows more easily, even in the small vessels. As a result of chemical changes, more oxygen is released to the tissues. These adaptations are so effective that if only half of your red cells remain, oxygen delivery may be about 75 percent of normal. A patient at rest uses only 25 percent of the oxygen available in his blood. And most general anesthetics reduce the body’s need for oxygen.

British doctors used this with a woman who had lost so much blood that “her haemoglobin fell to 1.8 g/dlitre. She was successfully treated . . . [with] high inspired oxygen concentrations and transfusions of large volumes of gelatin solution [Haemaccel].” (Anaesthesia, January 1987)