The patient in the photograph had failed to return to spontaneous respiration after the anaesthetic. We had obviously become fed up with squeezing the black rubber bag and elected to use the Manley ventilator. This was driven by compressed gas (oxygen) which was in very short supply. We were very reluctant to use it other that when absolutely necessary.
High pressure gas came in at the bottom left and inflated the bellows.
The pressure in the bellows was regulated by the sliding weight on the straight metal arm pivoted on the left.
The further to the right that the weight was slid on the arm the higher the pressure in the bellows.
The volume of gas to be delivered to the patient was regulated by the adjustment knob which could be slid up and down the curved graduated arm.
After the straight arm had hinged upwards to the set point the trip was tipped.
Input of gas stopped and a bellowsfull of gas was delivered to the patient.
Volume and pressure of gas could be precisely varied and delivered to the patient continuously and accurately rather that having to squeeze a bag.
As long as you had a supply of compressed gas………….