The fan and circulation pump use only 3.5 to 10 amps from the truck's battery -- which means there's no danger of draining the battery, Webasto says.

CNN: An eco-friendly way to cool big trucks

Lillehei solved that problem with cross-circulation, in which a donor, linked to the patient by plastic hose and a simple pump, acted as a living heart-lung machine.

FORBES: Brave heart