Automatic Oxygen Flow Regulated Non- Invasive Ventilator with Vital Sign Monitoring System

Mechanical ventilators emerged throughout the 19th century as the key tool to assist physicians & medical personnel to give effective life-saving treatment. Rapidly evolving situations like the COVID-19 pandemic led to a shortage of ventilators and oxygen supplies. On top of that, conventional ventilators don't come cheap, and ever since, the demand for medical oxygen supplies has skyrocketed; especially in least developed & developing countries. This paper proposes a non-invasive electromechanical ventilator design and hardware prototype that can save oxygen by controlling the inspiratory to expiratory time (I:E ratio) using an on-off or proportional solenoid valve. The proposed ventilator prototype utilizes the patient's oxygen saturation level (SpO2) and respiratory rate (RR) to determine the suitable I:e ratio. The SpO2 level is measured from a photoplethysmography (PPG) signal using a pulse oximeter sensor. The respiratory rate is obtained from the impedance pneumography technique using single channel two-terminal measurement. ECG data is also acquired from the same arrangement, which can record heart rate alongside a pulse oximeter. Besides these, the temperature sensor acquires body temperature information to monitor the patient's health status. The prototype is intended to be used as an in-house non-invasive ventilator which has an oxygen-saving capability with a vital sign monitoring system.