A rapidly deployable individualized system for augmenting ventilator capacity

A system of valves and sensors provides individualized respiratory support for two individuals from one ventilator, with acute testing in pigs. Divide and conquer Ventilators, machines that move air into and out of lungs, can be shared among patients in emergency situations, although this practice poses safety concerns. Srinivasan et al. developed a system of tubing, sensors, filters, and valves to provide individualized volume and pressure control to two or more individuals from a shared ventilator. The system was applied to open- and closed-circuit ventilators, provided temporary respiratory support to two artificial test lungs or pigs with differing pulmonary compliance and resistance, measured pulmonary mechanics, and accommodated sudden flow changes or the addition or removal of an individual from shared ventilation. Use of readily available materials enables the rapid deployment of this system. Strategies to split ventilators to support multiple patients requiring ventilatory support have been proposed and used in emergency cases in which shortages of ventilators cannot otherwise be remedied by production or procurement strategies. However, the current approaches to ventilator sharing lack the ability to individualize ventilation to each patient, measure pulmonary mechanics, and accommodate rebalancing of the airflow when one patient improves or deteriorates, posing safety concerns to patients. Potential cross-contamination, lack of alarms, insufficient monitoring, and inability to adapt to sudden changes in patient status have prevented widespread acceptance of ventilator sharing. We have developed an individualized system for augmenting ventilator efficacy (iSAVE) as a rapidly deployable platform that uses a single ventilator to simultaneously and more safely support two individuals. The iSAVE enables individual-specific volume and pressure control and the rebalancing of ventilation in response to improvement or deterioration in an individual’s respiratory status. The iSAVE incorporates mechanisms to measure pulmonary mechanics, mitigate cross-contamination and backflow, and accommodate sudden flow changes due to individual interdependencies within the respiratory circuit. We demonstrate these capacities through validation using closed- and open-circuit ventilators on linear test lungs. We show that the iSAVE can temporarily ventilate two pigs on one ventilator as efficaciously as each pig on its own ventilator. By leveraging off-the-shelf medical components, the iSAVE could rapidly expand the ventilation capacity of health care facilities during emergency situations such as pandemics.