Abstract: A process is provided for controlling at least one parameter of the breathing gas supply of a respirator with a patient connected to it as well as to a corresponding control device. The respiration pressure, the breathing gas flow generated by the respirator as well as the respiration rate may be used as parameters. The process presents the advantage that the control of the current respiration needs of the patient are taken into account by the muscle pressure (PMUS), i.e., the percentage of the airway pressure caused by the patient's own effort, being maintained at a value close to zero. An airway pressure (PAWC) is first calculated for this purpose from previously measured values for the airway pressure (PAW) and the breathing gas flow (d/dt V) and the mechanical parameters resistance (RL) and compliance (C) of the patient's lungs, which were determined therefrom, and this is subsequently compared with the actually measured value for the airway pressure (PAW).

Abstract: A process is provided for determining the functional residual capacity (FRC) of the lungs during respiration. An environmentally friendly trace gas is used in a process and system for determining the FRC by using fluoropropanes as a trace gas. Values for the FRC can thus be calculated, resolved for individual breaths, from the expiratory trace gas concentration and the expired breathing gas volume and they can be used for determining the FRC depending on their convergence behavior.

Abstract: A process is provided for determining the functional residual capacity (FRC) of the lungs during respiration. An environmentally friendly trace gas is used in a process and system for determining the FRC by using fluoropropanes as a trace gas. Values for the FRC can thus be calculated, resolved for individual breaths, from the expiratory trace gas concentration and the expired breathing gas volume and they can be used for determining the FRC depending on their convergence behavior.

Abstract: A respirator with an inhalation line (5) connected to a gas supply device (2) and with an exhalation line (7) connected to an exhalation device (3), with a Y piece (8) connecting the inhalation line (5) to the exhalation line (7), and with a patient connection (9) going out from the Y piece (8). Partial rebreathing of CO2-containing exhaled air is made possible in a simple manner by providing a switchover device (4) between the inhalation line (5) and the gas supply device (2) as well as between the exhalation line (7) and the exhalation device (3). The switchover device is designed such that the flow connection is established between the inhalation line (5) and the gas supply device (2) as well as the exhalation line (7) and the exhalation device (3) in a first switching position and there is at least a flow connection between the gas supply device (2) and the exhalation line (7) in the second switching position.

Abstract: A process and device for determining mechanical properties of a respiratory system of a patient connected to a respirator, wherein a short-term occlusion of the patient's airways is performed during an inspiration phase and/or an expiration phase. Initiating of the occlusion is at different points in time within the breathing cycle and during a plurality of breaths. The respiratory flow and the inhaled or exhaled volume of the patient is determined at the beginning of this occlusion. The airway pressure is also measured during this occlusion. The change occurring over time in the airway pressure during a measurement time falling within the occlusion time is determined. Also determined is the course over time of the change occurring over time of the muscle pressure of the patient from the measured values. The course over time of the muscle pressure is calculated by integrating this course over time.

Abstract: A respirator with a delivery device, which draws in ambient air via an inlet line and pumps it into an outlet line, with a discharge opening, which branches off from the outlet line and via which a partial flow of the gas being delivered, which can be set with a discharge valve, escapes. Oxygen is added with the smallest possible loss of gas and with good constancy of the concentration by: providing the inlet line with a buffer volume, via which the ambient air drawn in can flow; providing a return line which introduces the partial flow into the buffer volume is present between the discharge opening and the buffer volume; and providing the oxygen source connected to the inlet line and/or to the buffer volume.

Abstract: A ventilating system for supplying a patient with respiratory gas has an apparatus for measuring a respiratory gas flow curve 27 and a respiratory gas pressure curve 28 and has an evaluation circuit 8 for processing at least the respiratory gas flow curve and switching over the respiratory phases. As switchover values from one respiratory phase to the other, the evaluation circuit 8 utilizes predetermined trigger thresholds T.sub.IL, T.sub.EL of the respiratory gas flow curve 27. The ventilating system is improved in such a manner that a good adaptation thereof to the breathing effort of the patient 2 is provided even when leakage is present. This task is solved in that, in the evaluation circuit, the respiratory gas flow curve 27 and the respiratory gas pressure curve 28 are logically coupled during both the inspiratory phase and the expiratory phase. This logic operation takes place in accordance with a predetermined function. From the foregoing, an inspiratory trigger ancillary threshold Z.sub.

Abstract: The invention relates to a method for recognizing the respiratory phases of a patient for controlling a ventilating apparatus. The time-dependent trace of a signal, which represents the respiratory flow curve and is emitted by a signal device, is determined and from this trace, a trigger criterium is obtained for the switchover of the ventilating apparatus from the expiration phase into the inspiration phase and/or from the inspiration phase into the expiration phase. The method is improved in that even for chronically obstructive patients, a reliable and early recognition of the inspiration and expiration attempts is possible. A significant increase of the slope of the respiratory flow curve between each two zero crossovers of this curve is used as a trigger criterium.

Abstract: The invention is directed to a controllable expiration valve having a control valve for generating an end expiratory overpressure with the control valve providing the changeable control pressure. The expiration valve is improved so that it is made controllable for compensating dynamic end expiratory overpressure. For this purpose, the membrane chamber of the expiration valve as well as the outflow chamber of the control valve are connected with a device for generating an underpressure.