Abstract: In an artificial ventilation system and a method for controlling the artificial ventilation system for obtaining an optimized artificial ventilation of a lung system of a patient, optimal artificial ventilation is obtained when the blood system of the patient is maximally oxygenated and, at the same time, the negative influence on the cardio-pulmonary system is minimized. The ventilation system has a gas delivery unit for delivering controllable inspiration pulses to a patient, a monitoring unit for measuring at least one parameter related to the function of the lung system, such as a blood gas analyser, and a control unit for determining an optimal peak inspiratory pressure and pressure amplitude for the inspiration pulse based on the measured blood gas parameter.

Abstract: An arrangement for determining an opening pressure of a lung has a regulating unit which can deliver inspiration pulses to a patient's lung system, a blood gas analyzer for measuring the partial pressure of oxygen in the blood of the patient's circulatory system, and a control unit for determining an opening pressure based on the measured P.sub.a O.sub.2. When the measured P.sub.a O.sub.2 exceeds a predetermined threshold, the lung have opened sufficiently and a pressure value is correlated to the measured P.sub.a O.sub.2 and defined as the opening pressure.

Abstract: In an apparatus and method for determining an optimal opening pressure of a lung system a regulating unit delivers an inspiration pulse having an end pressure which is higher than the start pressure to the lung system. During the delivery of this inspiration pulse respiratory gas flow and pressure are measured by a measuring unit having a flow meter and a pressure gauge. The measured values are supplied to a control unit, in which measured flow and pressure are correlated and inflection points or regions in the flow-pressure-relation are identified. The highest pressure value related to an inflection point or region is defined as an interim opening pressure. By applying several different inspiration pulses, several interim opening pressures can be determined.