Abstract: An anesthetic breathing apparatus and system, having a patient circle system for re-breathing exhaled gases by a patient a volume reflector, a fresh gas delivery line, and a gas sensor unit arranged to measure a gas stream upstream a fresh gas connection and downstream said reflector unit. The gas sensor unit provides a signal for detection of a reflector driving gas (RDG) crossing over the volume reflector during inspiration based on at least one property of the gas stream measured by the gas sensor unit. Appropriate action may be taken based on this measurement, for instance in disclosed methods.

Abstract: A breathing apparatus has a first delivery device for adding a volume of a substance to a gas flow, the delivery device having a gas inlet and a gas outlet. A unit monitors a presence of the substance in a gas downstream the delivery device using a first sensor unit at the gas outlet that provides a first measurement value based on an acoustic property of a gas in a first conduit. A second sensor unit at the gas inlet provides a second measurement value based on an acoustic property of a gas present in the second conduit. A control unit determines the presence of the substance based on the first measurement value or based on a comparison of the first measurement value and the second measurement value.

Abstract: A breathing apparatus has a first delivery device for adding a volume of a substance to a gas flow, the delivery device having a gas inlet and a gas outlet. A unit monitors a presence of the substance in a gas downstream the delivery device using a first sensor unit at the gas outlet that provides a first measurement value based on an acoustic property of a gas in a first conduit. A second sensor unit at the gas inlet provides a second measurement value based on an acoustic property of a gas present in the second conduit. A control unit determines the presence of the substance based on the first measurement value or based on a comparison of the first measurement value and the second measurement value.

Abstract: A breathing apparatus has a first delivery device for adding a volume of a substance to a gas flow, the delivery device having a gas inlet and a gas outlet. A unit monitors a presence of the substance in a gas downstream the delivery device using a first sensor unit at the gas outlet that provides a first measurement value based on an acoustic property of a gas in a first conduit. A second sensor unit at the gas inlet provides a second measurement value based on an acoustic property of a gas present in the second conduit. A control unit determines the presence of the substance based on the first measurement value or based on a comparison of the first measurement value and the second measurement value.

Abstract: An anesthetic breathing apparatus and system, having a patient circle system for re-breathing exhaled gases by a patient a volume reflector, a fresh gas delivery line, and a gas sensor unit arranged to measure a gas stream upstream a fresh gas connection and downstream said reflector unit. The gas sensor unit provides a signal for detection of a reflector driving gas (RDG) crossing over the volume reflector during inspiration based on at least one property of the gas stream measured by the gas sensor unit. Appropriate action may be taken based on this measurement, for instance in disclosed methods.

Abstract: An anesthetic breathing apparatus and system, having a patient circle system for re-breathing exhaled gases by a patient, a volume reflector, a fresh gas delivery line, and a gas sensor unit arranged to measure a gas stream upstream a fresh gas connection and downstream said reflector unit. The gas sensor unit provides a signal for detection of a reflector driving gas (RDG) crossing over the volume reflector during inspiration based on at least one property of the gas stream measured by the gas sensor unit. Appropriate action may be taken based on this measurement, for instance in disclosed methods.

Abstract: A patient ventilation system has a flow regulating and gas mixing arrangement connected to an inspiratory channel of the system from which a gas mixture containing oxygen and at least a second gas is delivered to the system's proximal tubing. The proximal tubing further is connected to an expiratory channel and is connectable to a patient. The system further has at least two gas inlets connected to the flow regulating and mixing arrangement, and a gas identification unit in which the at least second gas supplied to the system via one of the gas inlets can be identified. By actively measuring a value that is dependent on the characteristics of the delivered gas, and by correcting the calibration of the flow regulating and gas mixing arrangement and/or the flow meter(s) based on this value, both safety and flow regulation in the system are enhanced.

Abstract: A device is directly or indirectly connectable to a patient for determining a volume related to the lungs of the patient. The device has an inspiration part through which a breathing gas passes towards the patient, and an expiration part through which the breathing gas passes away from the patient. The inspiration part has a mouthpiece for introducing a change of the gas composition in the breathing gas. The device implements a method for determining the volume with a detector being arranged in the expiration part that measures a measuring parameter which is dependent on the change in the gas composition, and with a calculation unit connected to the detector unit that determines the variation in the measuring parameter, and determines the volume from the determined variation.

Abstract: A breathing apparatus has a first delivery device for adding a volume of a substance to a gas flow, the delivery device having a gas inlet and a gas outlet. A unit monitors a presence of the substance in a gas downstream the delivery device using a first sensor unit at the gas outlet that provides a first measurement value based on an acoustic property of a gas in a first conduit. A second sensor unit at the gas inlet provides a second measurement value based on an acoustic property of a gas present in the second conduit. A control unit determines the presence of the substance based on the first measurement value or based on a comparison of the first measurement value and the second measurement value.

Abstract: An anesthetic breathing apparatus and system, having a patient circle system for re-breathing exhaled gases by a patient volume reflector, a fresh gas delivery line, and a gas sensor unit arranged to measure a gas stream upstream a fresh gas connection and downstream said reflector unit. The gas sensor unit provides a signal for detection of a reflector driving gas (RDG) crossing over the volume reflector during inspiration based on at least one property of the gas stream measured by the gas sensor unit. Appropriate action may be taken based on this measurement, for instance in disclosed methods.

Abstract: A patient ventilation system has a flow regulating and gas mixing arrangement connected to an inspiratory channel of the system from which a gas mixture containing oxygen and at least a second gas is delivered to the system's proximal tubing. The proximal tubing further is connected to an expiratory channel and is connectable to a patient. The system further has at least two gas inlets connected to the flow regulating and mixing arrangement, and a gas identification unit in which the at least second gas supplied to the system via one of the gas inlets can be identified. By actively measuring a value that is dependent on the characteristics of the delivered gas, and by correcting the calibration of the flow regulating and gas mixing arrangement and/or the flow meter(s) based on this value, both safety and flow regulation in the system are enhanced.

Abstract: A device is directly or indirectly connectable to a patient for determining a volume related to the lungs of the patient. The device has an inspiration part through which a breathing gas passes towards the patient, and an expiration part through which the breathing gas passes away from the patient. The inspiration part has a mouthpiece for introducing a change of the gas composition in the breathing gas. The device implements a method for determining the volume with a detector being arranged in the expiration part that measures a measuring parameter which is dependent on the change in the gas composition, and with a calculation unit connected to the detector unit that determines the variation in the measuring parameter, and determines the volume from the determined variation.

Abstract: In a method and an arrangement for acoustic determination of an instantaneous fluid temperature, acoustic velocity V in a fluid is monitored and an output signal related to the acoustic velocity is generated. A conventional temperature sensor senses a fluid temperature TS and generates an output signal related thereto.

Abstract: An apparatus for monitoring a gas supply connection to a mechanical breathing aid has an in-line housing containing a measurement chamber for receiving gas from the gas supply and a transceiver arrangement) operable to emit acoustic energy into and to detect emitted acoustic energy propagated through the measurement chamber. A comparator is operably connected to the transceiver arrangement to receive therefrom a signal dependent on an amplitude of detected energy and generates a control signal from a comparison of the received signal with a reference signal indicative of a target gas usable by a flow control valve, also located within the housing, to inhibit a gas flow through the breathing aid if a gas other than the target gas is present.

Abstract: A zero crossing detector has an analyzer which determines a zero level crossing of a currently input electrical pulse packet and which emits a trigger signal indicative of a determination having been made, and a pre-trigger unit which monitors variations in the amplitude of the current input pulse packet to detect a crossing of a pre-trigger level. The detector further includes a control unit operably connected to the pre-trigger unit which compares the amplitude of the pre-trigger level with any amplitude of a signal derived from the current or a previous input electrical pulse packet, and which automatically controls the amplitude of the pre-trigger level to maintain a working difference therebetween.

Abstract: In a method for determining the gas content, e.g. of oxygen in breathing gas in a breathing apparatus, and a breathing apparatus operating according to the method, the gas content is determined from the speed of sound in the breathing gas. In order to resolve the problems caused by temperature variations in gas samples, determination of the speed of sound is synchronized with one or more specific times in a respiratory cycle. Determination can then be made when conditions are most stable.

Abstract: In a method and an arrangement for acoustic determination of an instantaneous fluid temperature, acoustic velocity V in a fluid is monitored and an output signal related to the acoustic velocity is generated. A conventional temperature sensor senses a fluid temperature TS and generates an output signal related thereto.

Abstract: An arrangement to provide a moisture barrier and bacteria barrier for various medical components that is connected to a measuring tube, arranged in the flow paths of a respirator is simple and inexpensive and exchangeable and does not cause a flow resistance in the flow paths of the respirator. A carrier carries at least two moisture barriers and bacteria barriers such that one barrier, given a carrier introduced in the respirator, is arranged exactly in front of each component.

Abstract: An ultrasonic flow meter for measuring a flow in a measurement channel has a first sensor chamber with a first membrane arranged against the measurement channel and a first transducer arranged at a specific distance from the first membrane, and a second sensor chamber with a second membrane arranged against the measurement channel and a second transducer arranged at a specific distance from the second membrane is described. The first membrane and the second membrane are gas-tight. In order to reduce loads on the membrane, while still allowing the membrane to be made as thin as possible, the first sensor chamber and the second sensor chamber are gas-tight, a first gas line connects the first sensor chamber to the measurement channel and a second gas line connects the second sensor chamber to the measurement channel.

Abstract: An acoustic fluid flow meter has a timer for determining downstream and upstream transit times values of acoustic pulses transmitted between acoustic signal transceivers, operable alternately as transmitters and receivers, respectively, with and against the direction of fluid flow. Additionally an error signal indicator is supplied with the determined transit time values and emits an error signal indicative of a false flow reading if their sum and/or difference, particularly the sum of derived values, differs from a corresponding control value by a predetermined amount.