Disclosed are systems and processes related to cardiopulmonary resuscitation (CPR). One embodiment of the system comprises an inspiration chamber and an expiration chamber, which work cooperatively to provide gas (e.g., Oxygen (O.sub.2)) to a subject (e.g., human patient) during inspiration and extract and expel expired gas (e.g., Carbon Dioxide (CO.sub.2)) from the subject during expiration as a medical professional applies CPR to the subject. In other words, this disclosure provides systems and processes that allow for substantially synchronous chest compressions with positive pressure active inspirations and, also, substantially synchronous chest decompressions with negative pressure active expirations.

A method of controlling a flow rate of gases supplied to a patient by a respiratory assistance device includes controlling the supply gases flow rate so as to deliver gases to the patient according to a predetermined gases pressure/flow rate profile for at least a portion of the breathing cycle. A profile may be achieved that provides the patient with a particular benefit or therapy.

An apparatus and method for resuscitating a patient suffering from cardiac arrest or another condition in which normal circulation has been interrupted. A ventilator is used for delivering a gas mixture to the patient. The ventilator is configured to adjust the partial pressure of CO2 to one or more partial pressures high enough to slow expiration of CO2 from the patient's lungs and thereby maintain a reduced pH in the patient's tissues for a period of time following return of spontaneous circulation.

An apparatus and method for resuscitating a patient suffering from cardiac arrest or another condition in which normal circulation has been interrupted. A ventilator is used for delivering a gas mixture to the patient. The ventilator is configured to adjust the partial pressure of CO2 to one or more partial pressures high enough to slow expiration of CO2 from the patient's lungs and thereby maintain a reduced pH in the patient's tissues for a period of time following return of spontaneous circulation.

The disclosure provides a way to supplement the tidal volume delivered to the patient by a leaking re-breather when the delivered volume becomes less than that set by the ventilator (in either pressure-regulated or volume modes). This may be accomplished with a shunt—a gas conduit joining the non-patient side of the re-breather to the patient side. A low-resistance, plenum or a draw-over vaporizer may also be incorporated into the gas pathway. Such a device may include a housing with a movable partition separating an actuating side from a patient side. The housing includes a ventilator orifice for pneumatic communication between a ventilator and the actuating side and a patient orifice for pneumatic communication between the patient side and a patient. A shunt defines a bypass flow path from the actuating side and to the patient side when the moveable partition is at a maximal displacement towards the patient side.

A respiratory mask system is provided. The respiratory mask system has a patient interface that is secured to a user's head by a headgear. The patient interface includes a seal, a frame and a gas delivery conduit. The frame is configured to secure the seal and gas delivery conduit together. The frame includes a recessed channel and/or headgear retaining features configured to connect the headgear to the patient interface. The frame can include an inlet collar that connects to a gas delivery conduit. The inlet collar can include bias flow holes. The headgear includes a top strap, a pair of side arms, a yoke and a rear strap. The yoke is configured to connect to the recessed channel of the frame. The top strap, side arms and yoke form an integrally formed closed loop. The top strap can include two portions adjustably connected to each other.

A respiratory mask system is provided. The respiratory mask system has a patient interface that is secured to a user's head by a headgear. The patient interface includes a seal, a frame and a gas delivery conduit. The frame is configured to secure the seal and gas delivery conduit together. The frame includes a recessed channel and/or headgear retaining features configured to connect the headgear to the patient interface. The frame can include an inlet collar that connects to a gas delivery conduit. The inlet collar can include bias flow holes. The headgear includes a top strap, a pair of side arms, a yoke and a rear strap. The yoke is configured to connect to the recessed channel of the frame. The top strap, side arms and yoke form an integrally formed closed loop. The top strap can include two portions adjustably connected to each other.

The invention relates to devices, systems, and methods for recharging zirconium phosphate and/or zirconium oxide in reusable sorbent modules. The devices, systems, and methods provide for precision recharging of the zirconium phosphate and/or zirconium oxide to avoid the need of excess recharge solutions. The devices systems and methods also provide for calculation of the volumes of recharge solution needed for fully recharging the zirconium phosphate and zirconium oxide modules.

The present invention provides a method and apparatus for controlling a patient's body temperature and in particular for inducing therapeutic hypothermia. Various embodiments of the system are described. The system includes: a source of breathing gas, which may be in the form of a compressed breathing gas mixture; a heat exchanger or other heating and/or cooling device; and a breathing interface, such as a breathing mask or tracheal tube. Optionally, the system may include additional features, such as a mechanical respirator, a nebulizer for introducing medication into the breathing gas, a body temperature probe and a feedback controller. The system can use air or a specialized breathing gas mixture, such as He/O.sub.2 or SF/O.sub.2 to increase the heat transfer rate. In addition, the system may include an ice particle generator for introducing fine ice particles into the flow of breathing gas to further increase the heat transfer rate.

Disclosed are methods for measuring and controlling the gas temperature in medical procedures. In embodiments of the disclosed methods a gas is supplied to a patient using a gas supply device and a supply line. A heating system heats the gas using a heating wire prior to the gas being provided to the patient. A controller electrically controls the heating power of the heating wire based on an estimated value of a temperature at an exit of the heating system obtained from a mathematical estimation system, wherein a resistance of the heating wire is an input variable of the mathematical estimation system.