Intravenous Fluids

It is not possible to warm patients by administering heated fluids because the fluids cannot (much) exceed body temperature. On the other hand, heat loss from cold intravenous fluids becomes significant when large amounts of crystalloid solution or blood are administered. One unit of refrigerated blood or 1 L of crystalloid solution administered at room temperature decreases mean body temperature approximately 0.25°C. Fluid warmers minimize these losses and should be used when large amounts of intravenous fluid or blood are administered.

For routine cases, there are no clinically important differences among the available warmers. Although most warmers allow fluid to cool in the tubing between the heater and the patient, this cooling is of little consequence in adults: at high flows, little cooling occurs, and at low flows, the amount of fluid given is trivial.^[167] Special high-volume systems with powerful heaters and little resistance to flow facilitate the care of trauma victims and are useful in other cases in which large amount of fluid must be administered quickly.