In-Parallel Co-Ventilation - A Preliminary Experimental Study

Due to the large influx of patients with acute respiratory failure during COVID-19 pandemic, many hospitals were faced with severe shortages in mechanical ventilators. To remedy this issue, strategies have been proposed to split ventilators using an external circuit to ventilate two or more patients using one mechanical ventilator. However, current approaches require a physician to be present to titrate ventilator settings, which induces more clinical burden and strain on an already overworked healthcare workforce. Model-based method has been proposed for patient matching in co-ventilation, allowing physicians to estimate the feasibility of two different patients for co-ventilation, as well as forward simulating safe combinations of ventilator settings for immediate application. However, there is currently a lack of experimental results to prove the feasibility of this method. Hence, a multiplex co-ventilation circuit was developed for the experimental evaluation of the performance of model-based method, specifically a well-established single-compartment lung model. The ventilation circuit constructed was capable of delivering air to two mechanical test lungs with low circuit resistance. The ability to individualise airflow to each patient is achieved using a set of flow-resistive valves, which can independently control the air delivered to two lungs with differing properties.