Exemplary blankets can comprise a flexible fluid-impermeable outer shell having two outer layers sealed around their perimeters, a flexible radiant barrier layer positioned inside the outer shell and being reflective of radiant energy, and a flexible thermal insulation layer positioned inside the outer shell adjacent the radiant barrier layer and comprising a material having low thermal conductivity, such that the blanket is capable of retaining patient body heat by creating a barrier to conductive, convective, and radiant patient body heat loss. Some disclosed blankets include an air cell layer or material capable of entrapping air, inside the outer shell, such as an exemplary open cell foam layer. Some disclosed blankets are MRI-compatible.
