Abstract: A portable, battery-operated (e.g. 12 v.) electronic heater/humidifier is provided for hypothermia treatment. This heater/humidifier includes the combination of a casing provided with a heat exchanger system comprising an upper compartment loaded with a tangled mass of high heat conductivity material, and, serially-interconnected thereto, at least two serially-interconnected lower compartments, each such lower compartment being open at the bottom to a water reservoir and containing a lower horizontally-oriented heater element for heating water in the water reservoir and an upper porous hydrophilic batt. An airflow path is established between an air inlet and an air outlet, providing a one-way-flow airway system first through the tangled mass of high heat conductivity material, to transfer heat obtained conductively from the heater elements for pre-heating the incoming air and then through the porous hydrophilic batts, for wicking action of heated water to the site of vaporization in the air flow path.

Abstract: A heat exchanger, particularly useful as an inhalation rewarming apparatus for the treatment of hypothermia is provided herein. It includes an insulated container having one or more air inlets leading from lateral faces thereof to longitudinal inlet passages, then to transverse connecting passageways from the inlet passageways, and finally via a longitudinal hollow outlet conduit in the core thereof to an air outlet. A thermochemical heat source is disposed within the core of the container, such thermochemical heat source delineating two boundaries of the hollow outlet conduit and one boundary of each of the inlet passageways. A wrapping of a wettable, absorbent material encases the thermochemical heat source, such wrapping providing the actual above described boundaries. A loose filling or an air-permeable porous material having a large surface area and high heat capacity and high heat conductivity is disposed in the above-described passageways and outlet conduit.