Characterization study of pressure generated by automated Ambu-bag ventilator Available to Purchase

The automated Ambu-bag ventilator (AAV) is a type of simple respiratory equipment that is getting a lot of attention, especially during the latest COVID-19 pandemic. In order to avoid lung injury, the pressure character of the AAV needs to be known in advance. Therefore, a proper driving control strategy could be planned properly. This paper describes pressure character generated by pinch-type self-developed AAV prototype under several stepper motor movement strategies. The pressure generated by the device was measured by 16-bit data acquisition equipment which was then calibrated with the pneumatic pressure reference standard used in the Laboratory of “Standar Nasional Satuan Ukuran-Badan Standardisasi Nasional” (SNSU-BSN). Results show that the 1/4 step gives the least pressure vibration compared with the full-step and half-step modes. The linear movement profile of the actuator gives the most appropriate compression profile compared to other movement profiles such as logarithmic or ramp. The AAV has also been tested to service for a simulated patient condition: high airway resistance and smaller compliance. It results in higher airway pressure and peak pressure near 40 cmH₂O, which indicates the risk of overpressure that can damage the lung. A condition that should be taken care of properly in a real application.