Devices, systems and methods for endovascular temperature control

Abstract

Devices, systems and methods for controlling a patient's body temperature by endovascular heat exchange and/or surface heat exchange.

1 - 14 . (canceled) 
     
     
         15 . A body temperature management system comprising:
 a body heat exchanger positionable on or in a subject's body,   a heat exchange fluid warmer and/or cooler;   a heat exchange fluid pump which circulates heat exchange fluid through the heat exchange fluid warmer and/or cooler and through the body heat exchanger;   a sensor for sensing the subject's actual body temperature;   a user interface configured to receive a user-input patient temperature set point; and   a controller which receives signals indicating the user-input patient temperature and the currently-sensed actual body temperature;   wherein the controller is programmed to control the heat exchange fluid warmer or cooler and/or the heat exchange fluid pump to:   i) initially cause the system to perform a first phase of warming or cooling, during which the heat exchange fluid circulates through the body heat exchanger at temperature and flow rate to cause the sensed actual body temperature to increase or decrease until the sensed actual body temperature reaches a predetermined interim temperature, said interim body temperature being less than the user-input patient temperature set point if the subject is being warmed or greater than the patient temperature set point if the subject is being cooled; and, thereafter,   ii) cause the system to perform a second phase of warming or cooling to increase or decrease from the interim temperature to the user input temperature set point at one or more rates which are slower than said initial rate, until the sensed actual body temperature becomes equal to the user-input patient temperature set point without substantially overshooting the user input patient temperature set point; and, thereafter,   iii) cause the system to perform a third phase of warming or cooling during which the temperature and/or flow rate of the heat exchange fluid is/are periodically adjusted as needed to maintain the sensed actual body temperature substantially equal to the user-input patient temperature set point.   
     
     
         16 . A system according to  claim 15  wherein the user interface allows the user to select a rate of warming or cooling and the controller will cause the system to perform said first, second and third phases only when the selected rate of warming or cooling is greater than a triggering rate. 
     
     
         17 . A system according to  claim 16  wherein the triggering rate is greater than 0.1 degrees C. per hour. 
     
     
         18 . A system according to  claim 15  wherein the user interface allows the user to select a maximum rate of warming or cooling and the controller will cause the system to perform said first, second and third phases when the maximum rate is selected. 
     
     
         19 . A system according to  claim 15  wherein during the first phase the temperature and/or flow rate of the heat exchange fluid or pump speed is/are periodically adjusted as needed to cause the sensed actual body temperature to increase or decrease until the sensed actual body temperature reaches a predetermined interim temperature. 
     
     
         20 . A system according to  claim 15  wherein during the second phase the temperature and/or flow rate of the heat exchange fluid or pump speed is/are periodically adjusted as needed to cause the sensed actual body temperature to increase or decrease to the user input temperature set point. 
     
     
         21 . A system according to  claim 15  wherein during the first phase the temperature and flow rate of the heat exchange fluid are substantially constant and are not varied based on sensed changes in the actual patient temperature. 
     
     
         22 . A system according to  claim 15  wherein, during phase 2, the actual patient body temperature warms or cools at a rate of 0.05 degrees C. per hour to 0.1 degrees C. per hour. 
     
     
         23 . A system according to  claim 15  wherein the user interface allows the user to select a patient temperature set point and the controller will cause the system to perform said first, second and third phases only when the patient temperature set point is greater than a triggering patient temperature set point. 
     
     
         24 . A system according to  claim 21 , wherein the triggering patient temperature set point is greater than 37.8 degrees C.