Design of a Low-Cost Ventilator to Support Breathing for Patients with Respiratory Failure Arising from COVID-19

Abstract

In this work, two new, low cost, lightweight and simple pneumatic portable mechanical ventilator prototypes that offer minimal oxygen consumption were presented in support of treatment during the novel coronavirus (COVID-19) epidemic of 2020. The prototypes were implemented in ANSYS 18.0 and evaluated using Expert Systems 11.0 software. Both prototypes devices were found appropriate for all patients with difficulty breathing, which for patients with COVID-19, includes those with all severities of illness, recovery levels, and ages, no matter what the capacity of the patient’s respiratory system. To ensure the safety of the designed devices, the airway oxygen sensors, valves, and analysers were equipped with programmable alarms and other controllable safety attachments, including a modification to enable the delivery of nitric oxide (NO) for a specified therapy treatment recommended for respiratory failure. The overall prototype device capacity was obtained in terms of tidal volume/min. (TV), which was between 0.2 to 1.6 I./breath, suggesting that the device can be used treat patients of all ages, from children to adults. The prototype device has a range of 10 to 40 breaths/min. (bpm), and for normal spontaneous breathing, at an expiratory to inspiratory ratio E:I = 2:1, the designed prototype can produce a total tidal volume between 2.02 to 32.32 l/min. For patients with moderate breathing difficulties, i.e. with E:I ratios of 1:1, between 3.03 to 48.48 l/min. was estimated, with between 4.04 to 64.64 l/min for those with high severity of breathing issues, i.e. those with higher E:I ratios above 2:1. The designed ventilator can also be used for most oxygen consumption durations as it uses any oxygen fraction (concentration) of inspired oxygen-enriched in gas (FIO2) at an efficiency at least 0.42% higher than previous similar and standard ventilator devices.