Abstract:
A method for treating acute coronary syndromes (i.e., unstable angina or non-Q-wave MI) or transient ischemic attacks in a human or animal patient by placing a heat exchange apparatus in the patient's vasculature and using that heat exchange apparatus to cool the patient to a temperature (e.g. 30-36 degrees C.) at which platelet inhibition (i.e., inhibition of platelet activation and/or aggregation and/or adhesion) occurs. Anti-shivering drugs or anesthesia may be administered to patients whose body temperature is cooled below that patient's shivering threshold (typically approximately 35.5 degrees C.). If it is determined that platelet inhibition is no longer desirable, such as when the patient is about to undergo a surgical or interventional procedure wherein bleeding could be problematic, the hypothermia-induced platelet inhibition may be rapidly reversed by using the intravascular heat exchange apparatus to re-warm the patient's body to normothermia or near normothermia.
Abstract:
A catheter has an inner sleeve through which refrigerant circulates to and from a source of refrigerant. The catheter also has an outer sleeve surrounding the inner sleeve, including a distal end thereof. The outer sleeve is filled with a frozen biocompatible substance. The refrigerant is separated from the biocompatible substance by one or more walls of the inner sleeve such that the refrigerant is isolated from a patient in whom the catheter is positioned by both the inner sleeve and the frozen biocompatible substance. The refrigerant circulates through the catheter when the catheter is positioned in the patient to maintain the biocompatible substance frozen as heat is transferred from the patient to the biocompatible substance.
Abstract:
A kit of parts comprises a system and instructions for use for controlling patient temperature which uses a central venous line catheter having a heat exchange element. 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 heat exchange element. 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 catheter has a series of hollow loops arranged along a tube for carrying working fluid from a heat exchange system to exchange heat with a patient in whom the catheter is advanced. The loops when inflated are transverse to the catheter axis and parallel to each other, and circumscribe a hollow passageway through which blood can flow. Blood also flows around the outer perimeters of the loops.
Abstract:
A working fluid cassette for an intravascular heat exchange catheter includes a frame holding two closely spaced, square polymeric membranes along the sides of which are disposed inlet and outlet tubes. Working fluid from the catheter is directed from the inlet tube between the membranes to the outlet tube. The cassette is closely received between two refrigerant cold plates to exchange heat with the working fluid, which is circulated back to the catheter.
Abstract:
A heat exchange system for exchanging heat with working fluid from an intravascular heat exchange catheter or an external heat exchange pad includes a working fluid that circulates between the catheter or pad and a fluid cassette, and a refrigerant system that flows against the outer sides of cold plates between which the cassette is disposed. An outer wall of the system is transparent so that a person can view the refrigerant as it circulates, ensuring proper operation.
Abstract:
A compression belt cartridge for use with chest compression devices. The compression belt cartridge has a double-oar shaped belt and a cover plate through which the belt is threaded. The cover plate is provided with hooks and snap latches that fit into a belt drive platform. The cover plate is sized and dimensioned to fit within only selected platforms. The belt attaches to the means for tightening the belt via a spline attached to the belt. The means for tightening a belt then repetitively tightens the belt, thereby accomplishing chest compressions.
Abstract:
A boost converter for driving the gate of n-channel MOSFET power devices is described. The boost converter includes a monitoring circuit and a kick start circuit to quickly bring the boost converter online when required to drive the MOSFET on.
Abstract:
Safety mechanisms for compression belt cartridges used in chest compression devices. The safety mechanisms include a breakable link, liner socks, belt guards and a rapid-release connector. The breakable link ensures that unsafe belt tension will not occur. The liner socks protect the patient from friction and contain the breakable link. The belt guards protect foreign objects from entering the belt drive platform. The rapid-release connector allows the belt to be removed safely even during compressions.
Abstract:
A cooling system for an indwelling heat exchange catheter includes a heat exchange bath that is configured to receive a conduit that carries saline to and from the catheter. A heating/cooling fluid is in the bath and exchanges heat with the saline. The heating/cooling fluid flows through a heat exchanger that includes a refrigerant and two variable speed DC compressor for removing heat from the refrigerant. A gear pump circulates the working fluid to and from the catheter and is removably engaged with a pump support platform.