Advanced systems and methods for patient body temperature control

Abstract

Devices, systems and methods for controlling the temperature of all or part of the body of a human or animal subject.

1 - 82 . (canceled) 
     
     
         83 . A system for warming or cooling a target organ or anatomical region within a subject's vasculature to a target temperature, said system comprising:
 a heat exchanger configured to exchange heat with the subject's flowing blood at a heat exchange location;   a first temperature sensor configured to sense the temperature of the subject's flowing blood at a temperature sensing location, wherein the first temperature sensor is configured to be positioned downstream from the heat exchanger relative to a direction of the flowing blood;   a controller which receives signals from the first temperature sensor indicating the blood temperature being sensed at the temperature sensing location, wherein the controller comprises a processor programmed to estimate the temperature at the target organ or anatomical region based on the temperature sensed at the temperature sensing location, a heat capacity or heat responsiveness of at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region, and a power output of the heat exchanger,   wherein relative to the direction of the flowing blood, the at least one intervening organ or anatomical region is located downstream from the first temperature sensor and the target organ or anatomical region is located downstream from the at least one intervening organ or anatomical region,   wherein, based on the estimated temperature at the target organ or anatomical region, the controller controls the heat exchanger to warm or cool blood flowing through the heat exchange location as needed to result in warming or cooling of the target organ or anatomical region to the target temperature.   
     
     
         84 . The system according to  claim 83 , wherein the heat capacity or heat responsiveness of at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region is predetermined or estimated. 
     
     
         85 . The system according to  claim 83 , wherein the processor is programmed to estimate the temperature at the target organ or anatomical region based on the heat capacities of at least two intervening organs or anatomical regions between the temperature sensing location and the target location, wherein the heat capacity or heat responsiveness of a first intervening organ or anatomical region is predetermined and wherein the heat capacity or heat responsiveness of a second intervening organ or anatomical region is estimated. 
     
     
         86 . The system according to  claim 83 , further comprising a pump for pumping a heat exchange fluid through the heat exchanger to exchange heat with the subject's flowing blood, wherein the pumping of said heat exchange fluid through the heat exchanger is stopped periodically or occasionally and the heat capacity or heat responsiveness of at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region is estimated at each pump stop. 
     
     
         87 . The system according to  claim 86 , wherein the at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region includes at least a portion of the inferior vena cava and the left ventricle. 
     
     
         88 . The system according to  claim 83 , further comprising a second temperature sensor, wherein the first temperature sensor is located distal to the heat exchanger and the second temperature sensor is located proximal to the heat exchanger, such that the heat capacity or heat responsiveness of at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region is estimated without a pump stop or with a pump stop having a reduced duration. 
     
     
         89 . The system according to  claim 83 , wherein the organ or anatomical region in which the first and second temperature sensors are located is the inferior vena cava. 
     
     
         90 . The system according to  claim 83 , further comprising a second temperature sensor, wherein the second temperature sensor is located in the esophagus, such that the heat capacity or heat responsiveness of an organ or anatomical region near the esophagus can be estimated. 
     
     
         91 . The system according to  claim 83 , wherein the heat capacity or heat responsiveness of an intervening organ or anatomical region is estimated based on the sensed temperature in the esophagus. 
     
     
         92 . The system according to  claim 83 , further comprising a second temperature sensor, wherein the second temperature sensor is located in the pulmonary artery, such that the heat capacity or heat responsiveness of an organ or anatomical region near the pulmonary artery can be estimated. 
     
     
         93 . The system according to  claim 83 , wherein the target organ or anatomical region is selected from the left ventricle, brain, kidney or liver. 
     
     
         94 . The system according to  claim 83 , wherein the heat capacity or heat responsiveness of at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region is represented by a predetermined constant based on historical experimental temperature data of the at least one intervening organ or anatomical region. 
     
     
         95 . The system according to  claim 83 , wherein the heat capacity or heat responsiveness of at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region is estimated based on one or more patient parameters. 
     
     
         96 . The system according to  claim 83 , wherein the target organ or anatomical region is within the left ventricle of the subject's heart, the heat exchange location is within the subject's inferior vena cava or superior vena cava, and the temperature sensing location is in the subject's vasculature downstream of the heat exchange location. 
     
     
         97 . The system according to  claim 83 , wherein both the heat exchange location and the temperature sensing location are in the subject's inferior vena cava. 
     
     
         98 . The system according to  claim 83 , wherein the controller adjusts the power of the heat exchanger based on the estimated temperature at the target organ or anatomical region. 
     
     
         99 . The system according to  claim 83 , wherein the target organ or anatomical region is within the left ventricle of the subject's heart, the heat exchange location is within the subject's inferior vena cava or superior vena cava, and the temperature sensing location is in the subject's vasculature downstream of the heat exchange location. 
     
     
         100 . The system according to  claim 99 , wherein the controller comprising the processor programmed to estimate the temperature within the left ventricle makes the estimation based on the temperature sensed in the inferior vena cava and at least in part on a change in the left ventricle temperature calculated as a function of heating or cooling power of the heat exchanger over time and a change in the inferior vena cava temperature calculated as a function of heating or cooling power of the heat exchanger over time. 
     
     
         101 . The system according to  claim 83 , wherein the temperature at the target organ or anatomical region is estimated continually or intermittently. 
     
     
         102 . The system according to  claim 83 , wherein the temperature at the target organ or anatomical location is estimated intermittently at intervals of from approximately 1 to approximately 5 seconds. 
     
     
         103 . The system according to  claim 83 , wherein the temperature at the target organ or anatomical location is estimated continually in real time. 
     
     
         104 . The system according to  claim 83 , wherein the estimated temperature at the target organ or anatomical location is used as an indicator of or surrogate for the subject's core body temperature and the system is useable to control the subject's core body temperature. 
     
     
         105 . The system according to  claim 83 , wherein the estimate of the temperature at the target organ or anatomical location is used as an indicator of or surrogate for local temperature at the target location and the system is useable to control local temperature at the target location with or without incidental cooling or warming of the subject's core body temperature. 
     
     
         106 . A system for warming or cooling a target organ or anatomical region of a subject to a target temperature comprising:
 a heat exchanger configured to exchange heat with the subject at a heat exchange location;   a first temperature sensor configured to sense the temperature of the subject at a temperature sensing location, wherein the first temperature sensor is positionable at a location different from the heat exchange location;   a controller which receives signals from the first temperature sensor indicating the temperature being sensed at the temperature sensing location, wherein the controller comprises a processor programmed to estimate the temperature at the target organ or anatomical region based on the temperature sensed at the temperature sensing location, a heat capacity or heat responsiveness of at least one intervening organ or anatomical region between the temperature sensing location and the target organ or anatomical region, and a power output of the heat exchanger,   wherein the at least one intervening organ or anatomical region is located between the first temperature sensor and the target organ or anatomical region, and   wherein, based on the estimated temperature at the target organ or anatomical region, the controller controls the heat exchanger to warm or cool the heat exchange location as needed to result in warming or cooling of the target organ or anatomical region to the target temperature.   
     
     
         107 . The system according to  claim 106 , wherein the target organ or anatomical region is selected from the brain, kidney or liver. 
     
     
         108 . The system according to  claim 106 , wherein the first temperature sensor is located in the esophagus. 
     
     
         109 . The system according to  claim 106 , further comprising a second temperature sensor, wherein the second temperature sensor is located in the esophagus to estimate the heat capacity or heat responsiveness of an organ or anatomical region near the esophagus. 
     
     
         110 . The system according to  claim 108 , wherein the heat capacity or heat responsiveness of the at least one intervening organ or anatomical region is estimated based on the sensed temperature in the esophagus.