The invention discloses methods for preserving organs in brain-dead humans or cadavers which allows additional time for the organs to remain viable such that they may be harvested for subsequent transplantation. This invention also discloses methods for preserving and/or resuscitating organs in live (nonbrain-dead) patients, allowing for additional time to stabilize the patient's condition. The methods include the steps of instrumentizing (e.g., catheterizing, cannulating, injecting, etc.) the vessels or tissues around the organ, or the organ itself sought to be preserved and/or resuscitated, the body cavity, or cavities of the body, and introducing a temperature-controlled solution to preserve and/or resuscitate the organ(s). The temperature-controlled organ preservation solution includes components such as oxygen carrying agents, antioxidants, tissue damage reversing and protecting agents, carrier vehicles, diluents, nutrients, and anti-coagulating agents. A device which performs this method is also disclosed. This device includes a fluid reservoir, an oxygen tank, a heat exchanger and removable catheter lines.