Study outlines design guidelines for mechanical ventilators in PRITIs

New guidelines for designing mechanical ventilators that can work in low- and middle-income countries (LMICs) have been proposed. A ventilator developed according to the new guidelines is likely to meet demand in many of these countries.

The guidelines are based on the results of an original survey of over 50 anesthetist and intensivist experts from 23 PRITIs in Africa, Asia, Central and South America, and a critical review of published literature. .

The results of the study, published in the British Journal of Anesthesia and led by King’s College London, are vital for countries with few mechanical ventilators, as low ventilation capacity limits access to intensive care and to surgery. The guidelines have been produced to define the key design features of a mechanical ventilator to be usable and durable in low resource settings.

The COVID-19 pandemic has highlighted the lack of ventilators in many LMICs, and this study sought to characterize the infrastructure in which ventilators are needed. Fans produced for high-income countries may not be durable in LMICs, as they may be too difficult or expensive to repair.

Responses to the survey from major PRITI hospitals show that the electricity supply was interrupted daily (19%) and weekly (25%), but three-quarters of these outages lasted less than two hours. Thus, a relatively small battery in the ventilator could fill the gaps in the availability of electricity.

The study suggests that the design of a mechanical ventilator should also include an air compressor and either a gas cylinder or an oxygen concentrator.

The analysis has shown that there is a wide range of infrastructure in the LMICs.

Dr Federico Formenti, Reader in Physiology at King’s College London, said: “The pandemic has highlighted the lack of mechanical ventilation capacity in many LRICs, where the use of ventilators designed for wealthier countries is not is not sustainable for technical and financial reasons. Our study systematically examined the infrastructure and context in which ventilators are needed and, based on survey and expert opinion, we identified fundamental guidelines that could enable ventilator design. durable and context-specific mechanics for large LRIC hospitals.

Co-author Professor Madiha Hashmi, from Ziauddin University in Pakistan, added: “The COVID-19 pandemic has highlighted the shortage of respiratory support equipment in low-resource countries. Even when available, these complex machines are unable to save lives when used by untrained people. Simple ventilators with automatic modes can fill the lack of equipment and human resources.

Dr Mpoki Ulisubisya, Permanent Secretary at the Tanzanian Ministry of Health and co-author of the study, said: “The global unreliability of electricity supply in low- and middle-income countries necessitates that the design medical products and equipment is personalized. . This personalization is essential if we want to optimize patient care and provide quality that meets their needs. The pandemic has exacerbated this need when it comes to mechanical ventilation equipment, hence this study and the recommendations made for equipment for low- and middle-income countries.