Patent ID: 8459262

Claim:
A breathing apparatus for ventilating the lungs of a patient with breathing gas, comprising: a breathing circuit configured for interaction with a respirating subject; a mechanical ventilation system in communication with said breathing circuit to supply breathing gas to, and to receive exhaled gas from, the respirating patient, to satisfy mechanical ventilation mode requirements in a mechanical ventilation mode; a manual ventilation system configured to interact with the respirating subject to satisfy manual ventilation mode requirements in a manual ventilation mode, said manual ventilation system comprising a manually operable ventilation bag; a manual ventilation valve operable to place said manual ventilation system in communication with said breathing circuit to enable manual ventilation of breathing gas in said breathing circuit in said manual ventilation mode with manual operation of said ventilation bag; a pressure sensor that detects a pressure level, as a detected pressure level, in the breathing circuit; a control unit provided with said detected pressure level; an electronically controlled valve operated by said control unit dependent on said detected pressure level; said control unit being configured to operate said electronically controlled valve in said mechanical ventilation mode by adjusting the pressure level in the breathing circuit according to a first set of predetermined control rules adapted to said mechanical ventilation mode requirements, and to operate said electronically controlled valve in said manual ventilation mode by adjusting the pressure level in the breathing circuit according to a second set of predetermined control rules adapted to said manual ventilation mode requirements; said control unit being configured to operate said electronically controlled valve according to said second set of predetermined rules to at least, as a requirement among said manual ventilation mode requirements, prevent an overpressure in said breathing circuit that causes said respirating patient to resist manual ventilation in said manual ventilation mode; and said control unit being configured to operate said electronically controlled valve according to said first set of predetermined control rules as an expiration valve to, as requirements among said mechanical ventilation mode requirements, at least maintain said pressure level in the breathing circuit at a predetermined minimum pressure level, and enable a predetermined maximum pressure level in said breathing circuit in response to a detected predetermined pattern, selected from the group consisting of a pattern of said pressure level in said breathing circuit and a pattern of flow characteristics in said breathing circuit.