Abstract: Embodiments of the invention provide devices and methods for the in situ or in transit adjustment of the core body temperature of a patient. Devices according to some embodiments include a control unit and pressure chamber adapted to apply a pulsating negative pressure to a limb of the patient. An adjustment temperature applied during the application of the pulsating pressure can heat or cool the patient as necessary. Devices and methods disclosed herein can provide for efficient heating and/or cooling of a patient. In addition, devices and methods provide such functionality in a portable device that can be manually carried by an individual.