Paper Title
Research on Assist/Control Ventilation Methods Using Air Pressure Sensors for a Slider Type Mechanical Ventilator System Using AMBU Bag

In this paper,we investigated anairpressuresensor assisted/controlled ventilation method for patients capable of spontaneous breathing in a slider ventilator system with an Ambu bag.A new type coronavirus infection occurred in early December 2019, and the infection has spread worldwide. When it became severe, respiratory failure often occurs, and a shortage of ventilators are occurred as a result. On this situation, MIT has released a blueprint for a mechanical type ventilator using an Ambu bag.In the previous study, we started the development based on the MIT ventilator and developed a reliable low-cost slider-type mechanical ventilator system using the Ambu bag.In this ventilator system, ventilation was cyclical.However, patients who are able to breathe spontaneously may experience breathlessness due to the timing of breathing and ventilation.In this paper, three spontaneous breath sensing methods using one or two airpressure sensors are compared and discussed.First, the characteristics of the airpressure sensors were verified. Two airpressure sensors were used to measure pressure for a long period of time without the ventilator being driven. The results showed that the pressure changed by 0.34 cmH2O. The pressure of the two airpressure sensors was then compared when the ventilator was driven. Similar pressure waveforms were obtained for both. Finally, the person was fitted with a mask without the ventilator driven and the change in pressure due to breathing in a 4-second cycle was measured by the two airpressure sensors. Due to the air valve in the Ambu bag, less pressure was measured with the second airpressure sensor than with the first. These experiments showed that two airpressure sensors could be used to detect spontaneous breathing quickly and accurately. Keywords - Ventilator, Mechanical type, Ambu bag, MIT type ventilator, Slider type, Assist/Control Ventilation.