Abstract: Methods and apparatuses for temperature modification of a patient, or selected regions thereof, including an induced state of hypothermia. The temperature modification is accomplished using an in-dwelling heat exchange catheter within which a fluid heat exchange medium circulates. A heat exchange cassette of any one of several disclosed variations is attached to the circulatory flow lines of the catheter, the heat exchange cassette being sized to engage a cavity within one of various described re-usable control units. The control units include a heater/cooler device, a user input device, and a processor connected to receive input from various sensors around the body and the system. The heater/cooler device may be thermoelectric to enable both heating and cooling based on polarity. A temperature control scheme for ramping the body temperature up or down without overshoot is provided.

Abstract: A method for treating cardiac failure such as congestive heart failure by application of hypothermia. Hypothermia may be applied by endovascular cooling using a heat exchange catheter circulating heat exchange fluid between an external heat exchanger controlled using temperature feedback from a temperature probe on or in the patient to cool the heart to a sufficiently low temperature for a sufficient length of time to increase cardiac output and improve the vascular condition of the patient. The patient may be maintained in the hypothermic condition for a period of time and is then re-warmed slowly and controllably. The endovascular temperature management may be controlled automatically in response to a temperature probe on the patient, and shivering while the patient is cool may be combated using surface warming and anti-shivering drugs.

Abstract: A balloon catheter is used in a closed-loop heat exchange system for manipulating the temperature of a patient. The balloon catheter is positioned in the stomach of the patient, and then expanded with a heat exchange fluid delivered through a lumen formed in the shaft of the catheter. The balloon catheter comes into contact with the wall of the stomach, and the stomach substantially conforms around the expanded balloon catheter. The heat exchange fluid is allowed to flow continuously into and out of the balloon catheter. Heat is exchanged between the balloon catheter and the stomach so as to controllably alter the temperature of at least a portion of the patient. Anti-shivering mechanisms and automatic control based on temperature feedback from the patient may be used in connection with the heat exchange system.

Abstract: Heat exchanger-equipped catheters and related methods that are useable for changing or maintaining at least a portion of the body of a human or veterinary patient at a desired temperature and for the measurement of cardiac output or blood flow rate within a blood vessel, without the need for introduction of saline solution or any other foreign substance into the patient's blood.

Abstract: A balloon catheter is used in a closed-loop heat exchange system for manipulating the temperature of a patient. The balloon catheter is positioned in the stomach of the patient, and then expanded with a heat exchange fluid delivered through a lumen formed in the shaft of the catheter. The balloon catheter comes into contact with the wall of the stomach, and the stomach substantially conforms around the expanded balloon catheter. The heat exchange fluid is allowed to flow continuously into and out of the balloon catheter. Heat is exchanged between the balloon catheter and the stomach so as to controllably alter the temperature of at least a portion of the patient. Anti-shivering mechanisms and automatic control based on temperature feedback from the patient may be used in connection with the heat exchange system.

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 ?2-adrenoreceptor agonist, a non-opiod analgesic monoamine uptake inhibitor or neuropeptide 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 ?2-adrenoreceptor agonist?2-adrenoreceptor agonists, non-opiod analgesic monoamine uptake inhibitors and neuropeptides are disclosed including dexmedetomidine, nefopam, neurotensin and anticonvulsant medications and pharmaceutically acceptable salts thereof.

Abstract: A heat exchange fluid supply system for supplying a heat exchange fluid to an intravascular heat exchange catheter includes a disposable cassette having a bulkhead and an external heat exchanger, and which is configured to operate in combination with a reusable master control unit The bulkhead includes a reservoir section and a pump section. The reservoir section is provided with a means to monitor the amount of heat exchange fluid that is in the system. The bulkhead provides the mechanism for priming the system with heat exchange fluid from an external source and for circulating fluid to the catheter in a closed circuit. The pump section is configured to allow for pumping of heat exchange fluid at a constant pressure.

Abstract: Heat transfer catheter apparatus and methods of making and using same are disclosed wherein a fluid connection is provided between the distal portions of two adjacent, thin-walled, high strength fluid lumens to define a closed loop fluid circulation system capable of controlled delivery of thermal energy to or withdrawal of thermal energy from remote internal body locations.

Abstract: A heat exchange fluid supply system for supplying a heat exchange fluid to an intravascular heat exchange catheter includes a disposable cassette having a bulkhead and an external heat exchanger, and which is configured to operate in combination with a reusable master control unit. The bulkhead includes a reservoir section and a pump section. The reservoir section is provided with a means to monitor the amount of heat exchange fluid that is in the system. The bulkhead provides the mechanism for priming the system with heat exchange fluid from an external source and for circulating fluid to the catheter in a closed circuit. The pump section is configured to allow for pumping of heat exchange fluid at a constant pressure.

Abstract: A connector assembly for catheters having closed loop flow circuits, such as some balloon catheters and heat exchange catheters. The connector assembly comprises first and second connector bodies that may be connected and disconnected from one another. When the connector bodies are disconnected, a syringe or negative pressure source may be attached to withdraw residual fluid from the catheter's closed loop circuit and to deflate any expandable portion of the closed loop circuit (e.g., balloon or expandable heat exchanger). A one way flow valve prevents make up air or other fluid from entering the catheter while the negative pressure is being applied. Also disclosed are sterility barrier assemblies for all types of catheters.

Abstract: A temperature sensing system and method for determining a patient's core body temperature by measuring the temperature of the patient's blood at a location in a vessel lumen retrograde of an insertion point of a temperature sensor or sensors into the vessel lumen.

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 catheter system for controlling the body temperature of a patient by modifying the temperature of blood flowing within a blood vessel of the patient. The catheter system comprises a catheter body having a heat exchange region in contact with the blood; and a mechanism for moving the heat exchange surface, thereby increasing heat exchange between the heat exchange surface and blood flowing past the heat exchange surface. Various methods of moving the heat exchange surface are disclosed.

Abstract: Methods and apparatus for preventing myocardial infarction, or lessening the size/severity of an evolving myocardial infarction, by cooling at least the affected area of the myocardium using an intravascular heat exchange catheter. The heat exchange catheter may be inserted into the vasculature (e.g., a vein) and advanced to a position wherein a heat exchanger on the catheter is located in or near the heart (e.g., within the vena cava near the patient's heart). Thereafter, the heat exchange catheter is used to cool the myocardium (or the entire body of the patient) to a temperature that effectively lessens the metabolic rate and/or oxygen consumption of the ischemic myocardial cells or otherwise protects the ischemic myocardium from undergoing irreversible damage or infarction.

Abstract: Devices, systems and methods for treating disorders characterized by low cardiac output. The devices, systems and methods use intra-aortic balloon counterpulsation in combination with hypothermia of all or a portion of a human or veterinary patient's body to improve coronary perfusion and cardiac output. To effect the hypothermia, a heat exchange catheter may be positioned in the a patent's vasculature separately from the intra-aortic balloon counterpulsation catheter. Alternatively, a combination Intra-aortic balloon counterpulsation/heat exchange catheter may be utilized. Such combination catheter comprises a) a catheter sized for insertion into the aorta, b) a counterpulsation balloon and c) a heat exchanger. A drive/control system receives temperature and eletrocardiograph signals and drives the inflation/deflation of the counterpulsation balloon as well as the heating/cooling of the heat exchanger.

Abstract: A catheter for exchanging heat with a body fluid is disclosed. The catheter includes a main shaft and a heat exchange region having a plurality of heat exchange elements each having a length and opposed ends. Each of the elements is attached on at least one of its ends to the shaft and disposed so that when inserted in a fluid body cavity having body fluid therein, the body fluid may circumferentially surround each heat exchange element along a portion of the length of the heat exchange element. The catheter includes a fluid circulation path therein, which desirably includes the hollow lumen within each of heat exchange elements. The heat exchange elements may be connected at two points along the shaft using manifolds that are in fluid communication with fluid flow paths within the shaft. Alternatively, the heat exchange elements may be connected at only one point and be permitted to float in a proximal or distal direction with respect to 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: The heat exchange catheters comprise a catheter body having a heat exchange structure formed over a distal region thereof. Heat exchange structure comprises an elastic chamber or balloon which conforms closely to the catheter body when uninflated and which expands to enhance the available heat transfer surface when heat exchange medium is introduced. The elastic structures may consist of elastomeric sheets or membranes or may comprise non-distensible sheets or membranes having elastic elements in order to control expansion and contraction. Methods for fabrication and use are also disclosed.

Abstract: A catheter system for controlling the body temperature of a patient by modifying the temperature of blood flowing within a blood vessel of the patient. The catheter system comprises a catheter body having a heat exchange region in contact with the blood; and a mechanism for moving the heat exchange surface, thereby increasing heat exchange between the heat exchange surface and blood flowing past the heat exchange surface. Various methods of moving the heat exchange surface are disclosed.

Abstract: A catheter system for controlling the body temperature of a patient by modifying the temperature of blood flowing within a blood vessel of the patient. The catheter system comprises a catheter body having a heat exchange region in contact with the blood; and a temperature probe having a distal end that extends from the catheter body, thereby monitoring the temperature of blood flowing within the blood vessel.