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MICROPROCESSOR BASED VENTILATOR

Microprocessor based Ventilator

  •  Figure shows the block diagram of microprocessor controlled ventilator.(given below).
  • It consists of two inter-connected systems: The Pneumatic flow system and an Electronic control system.
  • The pneumatic flow system enables the flow of gas through the ventilator.
  • Oxygen and medical grade air enter the ventilator at 3.5 bar (50 psi) pressure. These gasses enter the air/oxygen mixer where they combine and gasses then enter a large reservoir tank.
  • An electronically controlled flow valve proportions the gas flow from the reservoir tank to the patient breathing circuit.
  •   As the gasses leave the ventilator, they pass by an oxygen analyzer, a safety ambient air inlet valve and a back-up mechanical over pressure valve.
  • The microprocessor controls each valve to deliver the desired inspiratory air and oxygen flows for mandatory and spontaneous ventilation.
  • The electronic control system may use one or more microprocessors and software to perform monitoring and control functions in a ventilator.

  • These parameters include setting of the respiration rate, flow waveform, tidal volume, oxygen concentration of the delivered breath, peak flow and PEEP.
  •  The sensors are connected to electronic processing circuits which makes them available for digital readouts. The signals are also compared with pre-set alarm levels so that if they fall outside a pre-determined normal range, alarms are sounded.
  • The pressure sensors are normally of semiconductor strain gauge type placed in a bridge configuration.
  • Block diagram for MICROPROCESSOR BASED VENTILATOR.

     

     

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