Image Number 3 for United States Patent #4801777.
A method and apparatus for rewarming blood (including refrigerated whole blood, packed red blood cells, and fresh frozen plasma) in which the temperature of the blood is quickly raised to infusion temperature without hemolysis or other damage to its constituents. The blood, contained in a conventional blood administration bag, is subjected to microwave irradiation while being totally immersed in a body of water. Structure is provided for immobilizing the blood bag within the body of water, and a sensor detects when a desired temperature has been attained and causes automatic cessation of microwave generation. The immobilizing structure may also be provided with a microwave-opaque barrier for shielding certain portions of a blood bag against excessive radiation exposure. A pump may also be provided for circulation of the water within the apparatus.