Mark 1 Pneumatic Rapid Response Ventilator Gallary
- Pneumatically driven piston is connected to standard air supply in the hospital wall. The tubing provided with the ventilator will have the necessary attachment provided to connect. Alternatively, it can be connected to a compressed air cylinder.
- Oxygen supply to the ambu bag will be connected to either standard oxygen supply in the hospital or compressed O2 cylinders.
- Tidal volume is controlled with the pneumatically driven piston that compresses the ambu bag and delivers set volume.
- Piston travel is controlled to allow the user to adjust the amount of pressure delivered to the ambu bag and hence the tidal volume.
- A timer allows control of respiratory rate.
- An additional timer provides an end inspiratory pause prior to the opening of the expiratory valve.
- An inspiratory limb valve is located within the ambu bag. Each breath is delivered through the inspiratory valve and then limb to the patient.
- Exhaled breaths are directed through the expiratory limb. A small portion of the exhaled breath will return to the inspiratory limb. Hence the potential for rebreathing and the need for intermittent flushing of the inspiratory limb to remove potentially accumulated CO2. This can be achieved by simply disconnecting the patient from the circuit for 3 - 4 breaths. If necessary, the patient can be manually ventilated during this time.
- Adjacent to the expiratory valve there is 1 PSI (51.7 mmHg) pressure release valve to ensure that pressure within the lungs does not exceed 35 mmHg mercury.
- PEEP (Positive End Expiratory Pressure) valve on the end of the expiratory limb prevents alveolar collapse at end of expiration. Permits 5 – 20 cmH2o of water.
- A HEPA filter is required between the circuit and the endotracheal tube to entrap virus and prevent it’s exhalation into the room.
- Pressure gage allows monitoring of airway pressure.
- The I:E ratio can be changed by adjusting the respiratory rate, tidal volume and flow control valve. The respiratory rate should be changed first, the tidal volume second and the flow control valve third. The flow control valve controls the down stroke speed of the piston.