Heat loss through intravenous (IV) tubing during a fresh whole blood (FWB) transfusion in austere environments can result in unhealthy fluid administration temperatures for patients. This research study aimed to quantify the amount of heat loss through the IV tubing during austere blood transfusions and propose mitigation methods, such as utilizing thermal insulation around the IV tubing and reducing the overall length of the tubing. Experiments were conducted in an environmental chamber where fluid temperature was controlled at the inlet of the IV tubing, while the resulting outlet fluid temperatures and volumetric flow rates were measured. The temperature within the environmental chamber was systematically reduced by 3°C from the first collection starting at 20°C to a final collection at -39°C. Heat loss analysis revealed that 40.9 (SD 3.4) W of heat was lost, even when the ambient temperature was 20 °C. As the environmental temperature reached -39°C, the heat loss through the IV tubing increased to 168 (SD 17.4) W. Significant heat loss occurs through IV tubing during blood transfusions in cold austere environments. Mathematical models suggest that thermal insulation around the IV tubing and reducing overall tubing length could effectively mitigate these losses.
Foust et al. (Mon,) studied this question.