A fluid warming cassette for use in a fluid warming system includes a
first sheet and second sheet joined with a flexed tensioning rod to form
a fluid container with a periphery in which the flexed tensioning rod is
disposed to tension the fluid container. The fluid container includes a
fluid channel with inlet and outlet ports in fluid communication with the
fluid channel. Preferably, the rod is flexed into an open-ended shape
such as a "U" shape. So flexed, the rod tensions the fluid container,
adding structural stability to the fluid warming cassette.