초록 ▼

With closed respiratory systems, the patient\s respiratory tract is tightly connected to a closed volume to which breathing gas is supplied only in the amount taken in by the patient. To this end, the breathing gas supply must be controlled. The controlled variable is either the pressure in the vent

With closed respiratory systems, the patient\s respiratory tract is tightly connected to a closed volume to which breathing gas is supplied only in the amount taken in by the patient. To this end, the breathing gas supply must be controlled. The controlled variable is either the pressure in the ventilating circuit, or the concentration of oxygen or the anesthetic gas in the breathing gas. A dropping pressure indicates either an increased consumption or a leak. To avoid insufficient or excessive loading of the patient, it is very important to be able to distinguish consumption from a leak. The inventive device makes this distinction possible. The breathing gas amounts are adjusted in the ventilating circuit at preset different pressures and are compared with each other, and the leak portion is computed therefrom.

대표청구항 ▼

A device for supplying gas for breathing to a closed ventilating circuit having a volume driver for circulating gas in the closed circuit, comprising: a metering unit controllable to supply a gas for breathing to the closed circuit; a controller connected to said metering unit for applying a supply

A device for supplying gas for breathing to a closed ventilating circuit having a volume driver for circulating gas in the closed circuit, comprising: a metering unit controllable to supply a gas for breathing to the closed circuit; a controller connected to said metering unit for applying a supply amount signal to said metering unit to control the supply of gas to the closed circuit; a pressure sensor adapted for connection to the closed circuit for generating an actual pressure signal corresponding to an actual pressure in the closed circuit; pressure switch means switchable to supply at least two different present pressure values for gas in the closed circuit; a differential amplifier having a first input connected to said pressure sensor for receiving the actual pressure signal and a second input connected to said pressure switch means for receiving one of said different preset pressure values, said difference amplifier having an output connected to said controller for applying an error signal value to said controller corresponding to a difference between said actual pressure value and said one of said preset pressure values; and a computer connected to said controller for receiving said supply amount signal, to said differential amplifier output for receiving said error signal value and to said pressure sensor for receiving said actual pressure signal, said computer connected to said pressure switch means for switching between said at least two different preset pressure values and adapted for connection to the volume driver for stopping and starting operation of the volume driver, said computer including means for calculating gas consumption for a patient connected to the closed circuit and for calculating a leakage value representing leakage from the closed circuit as a function of said error signal value and said supply amount signal wherein said computer is programmed to execute the equations E1=V+L(P1-P) E2=V+L(P2-P) wherein, P1 and P2 are the at least two different present pressure valves, P is the valve of the actual pressure signal, E1 and E2 are valves of supply amount signals for the at least two preset pressure valves, V is the consumption amount and L is the leakage amount.