Abstract: The invention provides a method and device for selectively controlling the temperature of a selected organ of a patient for performance of a specified application. The method includes introducing a guide catheter into a blood vessel. The guide catheter may have a soft tip and a retaining flange, and may be used to provide treatments such as administration of thrombolytic drug therapies, stenting procedures, angiographic procedures, etc. A supply tube is provided having a heat transfer element attached to a distal end thereof. The heat transfer element having a plurality of exterior surface irregularities, these surface irregularities having a depth greater than the boundary layer thickness of flow in the feeding artery of the selected organ. The supply tube and heat transfer element may be inserted through the guide catheter to place the heat transfer element in the feeding artery of the selected organ.

Abstract: The invention provides a method for substantially reducing the size of a thrombus in a blood vessel in which blood is flowing. The method includes delivering a heat transfer element to a blood vessel in fluid communication with a thrombosed blood vessel. The temperature of the heat transfer element is adjusted such that the same is sufficient to remove heat from the flowing blood. Heat is transferred from a volume including the thrombus to the heat transfer element. In a separate embodiment, heat may be delivered to the volume including the thrombus from the heat transfer element. The resultant temperature of the volume may be sufficient to substantially reduce the size of a thrombus. For example, the resultant temperature of the volume may be sufficiently high to substantially enhance plasminogen activation near the thrombus.

Abstract: An external fluid warming device is described that includes a fluid warming chamber and an air separation chamber. The fluid warming chamber has a fluid inlet that communicates with a fluid pathway. The air separation chamber that communicates with the fluid pathway has a fluid outlet and a gas outlet. A heating source, such as heat plates, are disposed adjacent the fluid pathway for transferring heat to the fluid. In use, the air separation chamber is positioned above the fluid warming chamber and the heating source. The fluid inlet is connected to a source of fluid and the fluid outlet is connected to an output device, such as an ultrafiltration machine. Gas generated during warming of the fluid collects at a top of the air separation chamber and is vented through the gas outlet, whereas fluid passes through a bottom of the air separation chamber and through the fluid outlet.

Abstract: A kit for establishing and maintaining hypothermia in a patient for neurotherapeutic purposes includes a high cooling capacity catheter that is advanced into the patient's central venous system to quickly cool the patient to, e.g., 32° C. or so. Once hypothermia has been established, the high capacity catheter is removed and replaced with a lower cooling capacity catheter which maintains a desired reduced temperature. The lower capacity catheter advantageously can be configured as a central venous catheter for permitting the catheter to be used for multiple functions. Alternatively, the high cooling capacity catheter can be used to attenuate a fever and lower the patient's body temperature to normal, with the lower capacity catheter being used to maintain normal body temperature.

Abstract: A kit for establishing and maintaining hypothermia in a patient for neurotherapeutic purposes includes a high cooling capacity catheter that is advanced into the patient's central venous system to quickly cool the patient to, e.g., 32° C. or so. Once hypothermia has been established, the high capacity catheter is removed and replaced with a lower cooling capacity catheter which maintains a desired reduced temperature. The lower capacity catheter advantageously can be configured as a central venous catheter for permitting the catheter to be used for multiple functions. Alternatively, the high cooling capacity catheter can be used to attenuate a fever and lower the patient's body temperature to normal, with the lower capacity catheter being used to maintain normal body temperature.

Abstract: A kit for establishing and maintaining hypothermia in a patient for neurotherapeutic purposes includes a high cooling capacity catheter that is advanced into the patient's central venous system to quickly cool the patient to, e.g., 32° C. or so. Once hypothermia has been established, the high capacity catheter is removed and replaced with a lower cooling capacity catheter which maintains a desired reduced temperature. The lower capacity catheter advantageously can be configured as a central venous catheter for permitting the catheter to be used for multiple functions. Alternatively, the high cooling capacity catheter can be used to attenuate a fever and lower the patient's body temperature to normal, with the lower capacity catheter being used to maintain normal body temperature.

Abstract: The present invention provides a method and apparatus for controlling the internal body temperature of a patient. According to the present invention, a catheter is inserted through an incision into a large blood vessel of a patient. By selectively heating or cooling a portion of the catheter lying within the blood vessel, heat may be transferred to or from blood flowing within the vessel and the patient's body temperature may thereby be increased or decreased as desired. The invention will find use in treating undesirable conditions of hypothermia and hyperthermia, or for inducing a condition of artificial hypothermia when desired. The method and system further provide for the cooling of initially hypothermic patients whose blood or body temperature has been warmed above the desired target level and the warming of initially hyperthermic patients whose blood or body temperature has been cooled below the desired target temperature.

Abstract: A method for treating cardiac arrest includes defibrillating the patient and/or ventilating the patient and/or administering a cardiac arrest drug such as epinephrine to resuscitate the patient, and then cooling the patient using one or more cooling catheter positioned in the central venous system of the patient.

Abstract: A heat exchange catheter having an expandable insulating region thereon. The catheter has a heat exchange region and the insulating region disposed proximally thereto. The insulating region assumes a first size about a catheter shaft to facilitate insertion of the catheter into the body. Once the insulating region is inserted into the body, the insulating region is expanded a second size. The insulating region may be a balloon around the catheter shaft that is inflated to the second size to create a gap between the wall of the balloon and the catheter shaft. Heat flows through the catheter shaft to and from the heat exchange region, and thus heat loss or gain to and from the surrounding body is minimized in the insulating region. The exchange region may include a fluid circulation path comprised of lumens through the catheter shaft.

Abstract: The present invention provides an enhanced method and device to inhibit or reduce the rate of restenosis following angioplasty or stent placement. The invention involves placing a balloon tipped catheter in the area treated or opened through balloon angioplasty immediately following angioplasty. The balloon, which can have a dual balloon structure, may be delivered through a guiding catheter and over a guidewire already in place from a balloon angioplasty. A fluid such as a perfluorocarbon may be flowed into the balloon to freeze the tissue adjacent the balloon, this cooling being associated with reduction of restenosis. The catheter may also be used to reduce atrial fibrillation by inserting and inflating the balloon such that an exterior surface of the balloon is in contact with at least a partial circumference of the portion of the pulmonary vein adjacent the left atrium.

Abstract: A catheter is adapted to exchange heat with a body fluid, such as blood, flowing in a body conduit, such as a blood vessel. The catheter includes a shaft with a heat exchange region disposed at its distal end. This region may include at least one balloon which is adapted to receive a remotely cooled heat exchange fluid preferably flowing in a direction counter to that of the body fluid. Embodiments including multiple balloons enhance the surface area of contact, and the mixing of both the heat exchange and the body fluid. The catheter can be positioned to produce hypothermia in a selective area of the body without cooling the entire body system. It is of particular advantage in brain surgeries where stroke, trauma or cryogenic tumors can best be addressed under hypothermic conditions.

Abstract: The invention provides a method of treating a patient infected with a human herpesvirus comprising raising the core temperature of the patient and then returning the core temperature of the patient to normal at least one time, wherein the core temperature is raised to a temperature range and a duration sufficient to reduce or eliminate the patient's viral load of the human herpesvirus.

Abstract: A catheter is adapted to exchange heat with a body fluid, such as blood, flowing in a body conduit, such as a blood vessel. The catheter includes a shaft with a heat exchange region disposed at its distal end. This region may include at least one balloon which is adapted to receive a remotely cooled heat exchange fluid preferably flowing in a direction counter to that of the body fluid. Embodiments including multiple balloons enhance the surface area of contact, and the mixing of both the heat exchange and the body fluid. The catheter can be positioned to produce hypothermia in a selective area of the body without cooling the entire body system. It is of particular advantage in brain surgeries where stroke, trauma or cryogenic tumors can best be addressed under hypothermic conditions.

Abstract: A catheter includes a plurality of primary leads to deliver energy for ligating a hollow anatomical structure. Each of the primary leads includes an electrode located at the working end of the catheter. Separation is maintained between the primary leads such that each primary lead can individually receive power of selected polarity. The primary leads are constructed to expand outwardly to place the electrodes into apposition with a hollow anatomical structure. High frequency energy can be applied from the leads to create a heating effect in the surrounding tissue of the anatomical structure. The diameter of the hollow anatomical structure is reduced by the heating effect, and the electrodes of the primary leads are moved closer to one another. Where the hollow anatomical structure is a vein, energy is applied until the diameter of the vein is reduced to the point where the vein is occluded. In one embodiment, a balloon is inflated to occlude the structure before the application of energy.

Abstract: The invention provides a device for heating or cooling a surrounding fluid in a feeding vessel and a method of manufacturing the same. The device includes a catheter assembly capable of insertion to a selected blood vessel in the vascular system of a patient. The assembly includes an elongated catheter body, a heat transfer element located at a distal portion of the catheter body and including an interior, an elongated supply lumen adapted to deliver a working fluid to the interior of the heat transfer element and having a hydraulic diameter, an elongated return lumen adapted to return a working fluid from the interior of the heat transfer element and having a hydraulic diameter, and wherein the ratio of the hydraulic diameter of the return lumen to the hydraulic diameter of the supply lumen is substantially equal to 0.75.

Abstract: Catheter devices and methods for intravascular heating and/or cooling of human or veterinary patients. The catheter devices generally comprise catheters having inflow and outflow lumens and at least one curvilinear balloon connected to the inflow and outflow lumens such that heat exchange fluid may be circulated through the balloon(s). The catheter is inserted into the vasculature and heated or cooled fluid is circulated through the balloon(s) to heat or cool blood flowing in heat-exchange proximity to the balloon(s), thereby effecting heating or cooling of all or a portion of the patient's body.

Abstract: The use of an intravascular cooling element to induce hypothermia in connection with a medical procedure. According to a first aspect of the present, invention, a coronary bypass procedure is conducted in which a patient's blood is oxygenated with the patient's lungs and in which blood is circulated using the patient's heart or using an intracorporeal pump. The procedure preferably comprises: (a) positioning a heat transfer element in a blood vessel of a patient; (b) cooling the body of the patient to less than 35° C., more preferably 32±2° C., using the heat transfer element; and (c) forming a fluid communicating graft between an arterial blood supply and the coronary artery. The body of the patient is preferably heated to about 37° C. using the heat transfer element subsequent to the step of forming the fluid communicating graft.

Abstract: A central venous catheter includes coolant supply and return lumens which communicate coolant to and from first and second heat exchange membranes arranged along the distal segment of the catheter. The coolant in the heat exchange membranes removes heat from the patient. Additional lumens are provided for conventional central venous catheter uses.

Abstract: A selective organ cooling device with a separate warming device for preventing secondary cooling which can result from cooling the selected organ. The cooling device applies cooling to the blood flowing in the feeder artery of the selected organ, while the body temperature control device warms the whole body either directly, or by warming blood returning to the heart from the selected organ, via a vein.

Abstract: A method for treating cardiac arrest includes defibrillating the patient and/or ventilating the patient and/or administering a cardiac arrest drug such as epinephrine to resuscitate the patient, and then cooling the patient's body temperature using one or more cooling catheters positioned in the central venous system of the patient and/or particularly cooling the patient's brain temperature using a catheter advanced into the aortic arch or into the carotid artery whereby a bolus of cold saline solution is introduced into the blood supplied to the brain to lower the brain temperature quickly, and further cooling or maintaining the brain temperature at a desired level by pumping coolant in a closed circuit formation between the catheter and the coolant source to remove heat from the blood supplied to the patient's brain.

Abstract: A catheter for intravascular corporeal cooling comprises an elongated tubular member having at least one lumen extending therethrough for providing cooled blood, an inflatable annular balloon positioned on the outer surface of the elongated tubular member, and a pressure reliever positioned in the external wall of the elongated tubular member and proximal to the annular inflatable balloon, wherein when the pressure of blood within a lumen reaches a predetermined value, the pressure reliever opens to permit fluid to be released from the elongated tubular member. In other embodiments of the invention the catheter may have two or more inflatable annular balloons that are separately inflatable and/or the catheter has an insulative outer annular member.

Abstract: A cooling apparatus having an inflatable balloon near a distal end of a multi-lumen catheter, with a plurality of blood flow passageways formed through the interior of the balloon from a proximal face of the inflated balloon to a distal face of the inflated balloon. Chilled saline solution is introduced through a supply lumen of the catheter to inflate the balloon in a feeding artery of the selected organ; this allows blood to flow through the blood flow passageways of the balloon, from one exterior face of the balloon to another exterior face. The saline solution continues to circulate around the blood flow passageways inside the balloon, to cool the blood, eventually exiting the balloon through a return lumen of the catheter.

Abstract: Methods and apparatus for temperature modification of selected body regions including an induced state of local hypothermia of the brain region for neuroprotection. A heat exchange catheter is provided with heat transfer fins projecting or extending outward from the catheter which may be inserted into selected blood vessels or body regions to transfer heat with blood or fluid in the selected blood vessels or body regions. Another aspect of the invention further provides methods and apparatus for controlling the internal body temperature of a patient. By selectively heating or cooling a portion of the catheter lying within a blood vessel, heat may be transferred to or from blood flowing within the vessel to increase or decrease whole body temperature or the temperature of a target region. Feed back from temperature sensors located within the patient's body allow for control of the heat transfer from the catheter to automatically control the temperature of the patient or of the target region within the patient.

Abstract: Apparatuses for use in whole body hypothermia include a high-flow hyperthermia circuit coupled to a low-flow dialysis circuit in a manner which reduces tensioning of membranes in the dialyzer of the dialysis circuit. The arrangement thereby allows proper membrane movement to assist in mixing a sorbent suspension circulated on the sorbent side of the dialyzer. Additional dialysis apparatuses include advantageous disposable packs including the dialyzer, sorbent heat exchangers arranged to cooperate with heating elements on base units of the apparatuses, and adaptations for very high flow rates useful in the hyperthermic treatment of cancers.

Abstract: A guidable catheter for heating or cooling a surrounding fluid in a feeding vessel in a vasculature of a patient. The catheter includes a heat transfer element, the heat transfer element having a plurality of exterior surface irregularities shaped and arranged to create turbulence in a surrounding fluid. The surface irregularities have a depth at least equal to the boundary layer thickness of flow of the surrounding fluid in the feeding vessel. The catheter assembly also includes a supply catheter having a portion disposed within the heat transfer element to deliver a working fluid to an interior of the heat transfer element. The catheter assembly further includes a return catheter to return a working fluid from the interior of the heat transfer element. A guidewire tube is provided adjacent one of the supply catheter or the return catheter and runs substantially parallel to the axis of the guidable catheter to receive a guidewire disposed within the guidewire tube.

Abstract: The present invention provides a method and apparatus for controlling the internal body temperature of a patient. According to the present invention, a catheter is inserted through an incision into a large blood vessel of a patient. By selectively heating or cooling a portion of the catheter lying within the blood vessel, heat may be transferred to or from blood flowing within the vessel and the patient's body temperature may thereby be increased or decreased as desired. The invention will find use in treating undesirable conditions of hypothermia and hyperthermia, or for inducing a condition of artificial hypothermia when desired.

Abstract: A system for controlling patient temperature uses a central venous line catheter having axially spaced distal and proximal heat exchange balloons. The central venous line catheter is provided with one or more lumens for providing access to the central blood supply of the patient, and with additional lumens for communicating heat exchange fluid to the balloons. Heat exchange fluid temperature is controlled through a feed back loop in which patient temperature is sensed and used to control a temperature control unit comprising a heating device and/or a cooling device in heat exchange relationship with the heat exchange fluid. A tubing set transports the heat exchange fluid between the central venous line and the temperature control unit, with a pump serving to circulate the fluid in a closed fluid circuit in the system.

Abstract: A central venous catheter includes coolant supply and return lumens which communicate coolant to and from first and second heat exchange membranes arranged along the distal segment of the catheter. The coolant in the heat exchange membranes removes heat from the patient. Additional lumens are provided for conventional central venous catheter uses.

Abstract: Apparatuses for use in whole body hypothermia include a high-flow hyperthermia circuit coupled to a low-flow dialysis circuit in a manner which reduces tensioning of membranes in the dialyzer of the dialysis circuit. The arrangement thereby allows proper membrane movement to assist in mixing a sorbent suspension circulated on the sorbent side of the dialyzer. Additional dialysis apparatuses include advantageous disposable packs including the dialyzer, sorbent heat exchangers arranged to cooperate with heating elements on base units of the apparatuses, and adaptations for very high flow rates useful in the hyperthermic treatment of cancers.

Abstract: A method and apparatus for performing hypothermia of a selected organ without significant effect on surrounding organs or other tissues. A flexible coaxial catheter is inserted through the vascular system of a patient to place the distal tip of the catheter in an artery feeding the selected organ. A chilled perfluorocarbon fluid is pumped through an insulated inner supply conduit of the catheter to cool a flexible bellows shaped heat transfer element in the distal tip of the catheter. The heat transfer bellows cools the blood flowing through the artery, to cool the selected organ, distal to the tip of the catheter.

Abstract: A selective organ heat transfer device with deep irregularities in a turbulence-inducing exterior surface. The device can have a plurality of elongated, articulated segments, each having a turbulence-inducing exterior surface. A flexible joint connects adjacent elongated, articulated segments. The flexible joint may be a rubber tube or a metal tube of a predetermined thickness. An inner lumen is disposed within the heat transfer segments. The inner lumen is capable of transporting a pressurized working fluid to a distal end of the heat transfer element.

Abstract: Methods and apparatus for temperature modification of selected body regions including an induced state of local hypothermia of the brain region for neuroprotection. A heat exchange catheter is provided with heat transfer fins projecting or extending outward from the catheter which may be inserted into selected blood vessels or body regions to transfer heat with blood or fluid in the selected blood vessels or body regions. Another aspect of the invention further provides methods and apparatus for controlling the internal body temperature of a patient. By selectively heating or cooling a portion of the catheter lying within a blood vessel, heat may be transferred to or from blood flowing within the vessel to increase or decrease whole body temperature or the temperature of a target region. Feed back from temperature sensors located within the patient's body allow for control of the heat transfer from the catheter to automatically control the temperature of the patient or of the target region within the patient.

Abstract: The invention provides a method and device for selectively controlling the temperature of a selected organ of a patient for performance of a specified application. The method includes introducing a guide catheter into a blood vessel. The guide catheter may have a soft tip and a retaining flange, and may be used to provide treatments such as administration of thrombolytic drug therapies, stenting procedures, angiographic procedures, etc. A supply tube is provided having a heat transfer element attached to a distal end thereof. The heat transfer element having a plurality of exterior surface irregularities, these surface irregularities having a depth greater than the boundary layer thickness of flow in the feeding artery of the selected organ. The supply tube and heat transfer element may be inserted through the guide catheter to place the heat transfer element in the feeding artery of the selected organ.

Abstract: The invention provides a method for substantially reducing the size of a thrombus in a blood vessel in which blood is flowing. The method includes delivering a heat transfer element to a blood vessel in fluid communication with a thrombosed blood vessel. The temperature of the heat transfer element is adjusted such that the same is sufficient to remove heat from the flowing blood. Heat is transferred from a volume including the thrombus to the heat transfer element. In a separate embodiment, heat may be delivered to the volume including the thrombus from the heat transfer element. The resultant temperature of the volume may be sufficient to substantially reduce the size of a thrombus. For example, the resultant temperature of the volume may be sufficiently high to substantially enhance plasminogen activation near the thrombus.

Abstract: A method is provided of localizing a drug action where the drug is present throughout a vascular system. The localization occurs to within a volume of blood in a blood vessel, the vascular system having an initial temperature substantially within a first temperature range. A temperature-specific enzyme is delivered throughout a vascular system including a volume of blood in a blood vessel, the temperature-specific enzyme having a working temperature within a prespecified temperature range that does not substantially overlap the first temperature range. A heat transfer element is delivered to a blood vessel in fluid communication with the volume of blood. The temperature of the heat transfer element is adjusted such that the volume of blood in the blood vessel is heated or cooled to the prespecified temperature range. In this way, the action of the temperature-specific enzyme is substantially limited to the volume of blood heated or cooled.

Abstract: A selective organ heat transfer device with deep irregularities in a turbulence-inducing exterior surface. The device can have a plurality of elongated, articulated segments, each having a turbulence-inducing exterior surface. A flexible joint connects adjacent elongated, articulated segments. An inner lumen is disposed within the heat transfer segments. The inner lumen is capable of transporting a pressurized working fluid to a distal end of the heat transfer element. The irregularities may be grooves, and the grooves have a curved termination point which directs blood along a direction having a component perpendicular to the axis of the segments, thereby enhancing turbulence and heat transfer.

Abstract: A method and apparatus for performing hypothermia of a selected organ without significant effect on surrounding organs or other tissues. A flexible catheter is inserted through the vascular system of a patient to place the distal tip of the catheter in an artery feeding the selected organ. A compressed refrigerant is pumped through the catheter to an expansion element near the distal tip of the catheter, where the refrigerant vaporizes and expands to cool a flexible heat transfer element in the distal tip of the catheter. The heat transfer element cools the blood flowing through the artery, to cool the selected organ, distal to the tip of the catheter.

Abstract: A method and apparatus for lowering the body temperature of a patient while reducing shivering by using a heat exchange device in combination with an anti-shivering mechanism that temporarily reduces shivering. The devices disclosed include a catheter having a heat exchange balloon thereon with heat exchange fluid circulating through the interior of the balloon. The heat exchange balloon is placed in the vasculature of a patient, and heat exchange fluid at a temperature other than the temperature of the blood in the vasculature is circulated through the interior of the balloon to add or remove heat from the blood of the patient. Various anti-shivering agents are disclosed including dopamine receptor blockers, dopamine receptor agonists, &kgr; opioid receptor agonists, opioid agonist-antagonist analgesics, seratonin 5 HT1a agonists, and pharmaceutically acceptable salts of any members of this group. Specific examples of each are give.

Abstract: A method and apparatus for performing hypothermia of a selected organ without significant effect on surrounding organs or other tissues. A flexible coaxial catheter is inserted through the vascular system of a patient to place the distal tip of the catheter in an artery feeding the selected organ. A chilled perfluorocarbon fluid is pumped through an insulated inner supply conduit of the catheter to cool a flexible bellows shaped heat transfer element in the distal tip of the catheter. The heat transfer bellows cools the blood flowing through the artery, to cool the selected organ, distal to the tip of the catheter.

Abstract: The present invention involves a selective organ heat transfer device having a flexible coaxial catheter capable of insertion into a selected feeding artery in the vascular system of a patient. A heat transfer element is attached to a distal portion of the catheter as well as a turbulence-enhancing element which is adapted to enhance turbulent blood flow along the heat transfer element. The heat transfer element may include the turbulence-enhancing element and/or a turbulence-enhancing element may be located proximal of the heat transfer element.

Abstract: A catheter includes a first plurality of expandable leads and a second plurality of expandable leads separate and longitudinally spaced-apart from the first plurality to deliver energy to a hollow anatomical structure, such as vein, fallopian tube, hemorrhoid, esophageal varix, to effectively ligate that structure. Each of the leads includes an electrode located at the distal end of the respective electrode lead. Polarizations of the leads may be selected to achieve the power distribution desired. Each electrode lead includes an outward bend such that when a movable sheath is moved out of contact with the leads, they expand outwardly into apposition with an inner wall of the structure to be ligated. High frequency energy can be applied from the leads to create a heating effect in the surrounding tissue of the anatomical structure.

Abstract: An apparatus for use in whole body hypothermia includes a dialyzer having a blood side and a dialysate side separated by one or more dialysis membranes. A blood pump associated with the a blood circuit established on the blood side circulates blood through the dialyzer at high rates advantageous for hyperthermia treatments. A bypass is included whereby circulated blood can bypass the dialyzer. The bypass aids in preventing blood-side tensioning of dialyzer membranes thereby allowing proper membrane movement to assist in mixing a sorbent suspension circulated on the dialysate side of the dialyzer. A sorbent suspension composition for use as a dialysate in hemodialysis, especially when performed in conjunction with whole body hyperthermia, includes water, a surface adsorptive agent such as charcoal, a cation exchanger, and precipitated calcium phosphate. The precipitated calcium phosphate serves as a reservoir for calcium and phosphate ions to assist in controlling patient blood chemistries.

Abstract: The present invention provides a method and apparatus for controlling the internal body temperature of a patient. According to the present invention, a catheter is inserted through an incision into a large blood vessel of a patient. By selectively heating or cooling a portion of the catheter lying within the blood vessel, heat may be transferred to or from blood flowing within the vessel and the patient's body temperature may thereby be increased or decreased as desired. The invention will find use in treating undesirable conditions of hypothermia and hyperthermia, or for inducing a condition of artificial hypothermia when desired. The method and system further provide for the cooling of initially hypothermic patients whose blood or body temperature has been warmed above the desired target level and the warming of initially hyperthermic patients whose blood or body temperature has been cooled below the desired target temperature.

Abstract: The present invention provides a method and apparatus for controlling the internal body temperature of a patient. According to the present invention, a catheter is inserted through an incision into a large blood vessel of a patient. By selectively heating or cooling a portion of the catheter lying within the blood vessel, heat may be transferred to or from blood flowing within the vessel and the patient's body temperature may thereby be increased or decreased as desired. The invention will find use in treating undesirable conditions of hypothermia and hyperthermia, or for inducing a condition of artificial hypothermia when desired. The method and system further provide for the cooling of initially hypothermic patients whose blood or body temperature has been warmed above the desired target level and the warming of initially hyperthermic patients whose blood or body temperature has been cooled below the desired target temperature.

Abstract: A method for performing hypothermia of a selected organ without significant effect on surrounding organs or other tissues. A flexible coaxial catheter is inserted through the vascular system of a patient to place the distal tip of the catheter in an artery feeding the selected organ. A chilled perfluorocarbon fluid is pumped through an insulated inner supply conduit of the catheter to cool a flexible bellows shaped heat transfer element in the distal tip of the catheter. The heat transfer bellows cools the blood flowing through the artery, to cool the selected organ, distal to the tip of the catheter.

Abstract: A catheter is adapted to exchange heat with a body fluid, such as blood, flowing in a body conduit, such as a blood vessel. The catheter includes a shaft with a heat exchange region disposed at its distal end. This region may include at least one balloon which is adapted to receive a remotely cooled heat exchange fluid preferably flowing in a direction counter to that of the body fluid. Embodiments including multiple balloons enhance the surface area of contact, and the mixing of both the heat exchange and the body fluid. The catheter can be positioned to produce hypothermia in a selective area of the body without cooling the entire body system. It is of particular advantage in brain surgeries where stroke, trauma or cryogenic tumors can best be addressed under hypothermic conditions.

Abstract: The present invention provides a method and apparatus for controlling the internal body temperature of a patient. According to the present invention, a catheter is inserted through an incision into a large blood vessel of a patient. By selectively heating or cooling a portion of the catheter lying within the blood vessel, heat may be transferred to or from blood flowing within the vessel and the patient's body temperature may thereby be increased or decreased as desired. The invention will find use in treating undesirable conditions of hypothermia and hyperthermia, or for inducing a condition of artificial hypothermia when desired.

Abstract: A method and apparatus for performing hypothermia of a selected organ without significant effect on surrounding organs or other tissues. A flexible catheter is inserted through the vascular system of a patient to place the distal tip of the catheter in an artery feeding the selected organ. A compressed refrigerant is pumped through the catheter to an expansion element near the distal tip of the catheter, where the refrigerant vaporizes and expands to cool a flexible heat transfer element in the distal tip of the catheter. The heat transfer element cools the blood flowing through the artery, to cool the selected organ, distal to the tip of the catheter.

Abstract: The present invention provides a method and apparatus for controlling the internal body temperature of a patient. According to the present invention, a catheter is inserted through an incision into a large blood vessel of a patient. By selectively heating or cooling a portion of the catheter lying within the blood vessel, heat may be transferred to or from blood flowing within the vessel and the patient's body temperature may thereby be increased or decreased as desired. The invention will find use in treating undesirable conditions of hypothermia and hyperthermia, or for inducing a condition of artificial hypothermia when desired. The method and system further provide for the cooling of initially hypothermic patients whose blood or body temperature has been warmed above the desired target level and the warming of initially hyperthermic patients whose blood or body temperature has been cooled below the desired target temperature.

Abstract: A non-invasive method and apparatus for at least partially occluding the descending aorta of a patient and for manipulating core and cerebral temperature includes positioning an elongated tubular member which may have a moveable surface through the esophagus and displacing the moveable surface thereby applying a force posteriorly in the direction of the patient's descending aorta sufficient to partially or substantially completely occlude the descending aorta. The tubular member may include a heat exchange surface and a heat transfer mechanism for transferring heat to the heat transfer surface or for transferring heat from the heat transfer surface in order to modify the temperature of a portion of the patient.