Patent ID: 7851729

Claim:
A method of warming a patient during surgery, the method comprising: providing a heating blanket comprising a flexible sheet-like heating element having generally uniform electrical resistance per unit area such that the heating element produces a substantially uniform watt density output across a surface area thereof when the heating element is electrically powered, the heating element including a first side and a second side opposite the first side, the first side having a temperature sensor coupled thereto at a location that defines a first temperature zone of the heating element; placing the heating blanket over a patient, such that the second side of the heating element faces toward the patient, the first temperature zone of the heating element is in thermal conductive contact with the patient, and a second temperature zone of the heating element is alongside the patient but not in thermal conductive contact with the patient; monitoring a temperature of the first temperature zone of the heating element, as sensed by the temperature sensor, after the blanket is placed over the patient; and controlling electric power to the heating element, according to the monitored temperature of the first temperature zone; and maintaining a first temperature of the first temperature zone only, the maintained first temperature being lower than a second temperature of the second temperature zone, after the blanket is placed over the patient.