Source: University of Canterbury
20 May 2020
A simple, low-cost technology developed by University of Canterbury (UC) engineers could save thousands of patients’ lives around the world by doubling the capacity of ventilators in hospital intensive care units, boosting their capacity to treat surges of Covid-19 patients during outbreaks.
A simple, low-cost technology developed by University of Canterbury (UC) engineers could save thousands of patients’ lives around the world by doubling the capacity of ventilators in hospital intensive care units, boosting their capacity to treat surges of Covid-19 patients during outbreaks.
Distinguished Professor Geoff Chase, from UC’s College of Engineering, has worked with Christchurch Hospital Senior Intensive Care Specialist Geoff Shaw, Professor Merryn Tawhai of the Auckland Bioengineering Institute, and engineers and senior doctors in Belgium and Malaysia to allow two patients to use one ventilator safely and effectively, using a novel active valve concept.
A project to develop, test, and initially deploy the unique system has just been awarded $150,000 from the Ministry of Business Innovation and Employment’s Covid-19 Innovation Fund.
A first prototype has already been made and put into action using mechanical lungs attached to a ventilator at UC’s Department of Mechanical Engineering and testing will move to Christchurch Hospital soon.
The UC-led international research team plans to test, prove and then distribute the active breathing circuit system globally on an “open source” basis, so its software and designs would be freely available.
“We believe this can, and will, save countless lives internationally by doubling ventilator capacity and sparing doctors from having to make terrible end-of-life care choices,” Prof Chase says. “It will provide time for health systems to weather the Covid-19 pandemic storm when major outbreaks occur by increasing intensive care capacity. In New Zealand, a doubling would mean hospitals could, in the short term, provide mechanical ventilation to something like 460 patients instead of being limited to around 230 ventilated ICU beds currently.
“This is a clever technology. It’s very simple, quickly implemented, and low-cost, but high impact, solution. We can have the first prototypes ready in one to three months, or faster, and pilot-trial tested quickly after that. We will develop them locally and then make them available internationally with freely available software and designs to be 3D printed in hospitals,” Prof Chase says.
Worldwide there is a shortage of ventilators because critically ill Covid-19 patients need mechanical ventilation to control breathing and allow recovery, sometimes for more than three weeks. In several countries the wave of novel coronavirus patients has overwhelmed hospital resources.
Through strong early action New Zealand has so far avoided such a feared influx of patients. However, it has one of the lowest numbers of ventilated intensive care unit beds per 100,000 population in the first world, and both modelling and experience in the rest of the world has shown this capacity could be exceeded if demand increased rapidly in a major outbreak.
The new technology uses mechatronics and modern manufacturing – such as 3D printing – to create a pressure sensor driven active control valve system that lets each patient breathe alternately one at a time. This approach is known as “in series” breathing.
Despite internet popularity, using a single ventilator for more than one patient, where they all breathe together or “in parallel” is seen by medical experts as too risky. However, Prof Chase and Prof Shaw and their team have shown how this low-cost active breathing circuit concept using “in series” breathing allows it to be done safely. Their concept was just described and published in Critical Care, a leading intensive care medicine journal.
“This all-new approach will require very little change to current clinical ventilation practice,” Prof Shaw says. “The device and active breathing circuit we’ve proposed is a technology extension that enables each patient connected to a ventilator to be treated individually by the machine, instead of breathing in parallel at the same time, which is higher risk to both patients. We believe our technology could also lead to improvements in other areas of ventilation care.”
His team is collaborating with ICU clinicians in Christchurch, Malaysia and Belgium on testing and proof of concept, with the research led from New Zealand. This international team shares over 15 years of joint research on intensive care medicine, creating novel innovations that have significantly improved care and outcomes for many patients.
“This system is another example of how clinicians and engineers can successfully work together to create innovative products that can solve urgent international problems,” Prof Chase says.
The other members of the team are Prof Merryn Tawhai at the Auckland Bioengineering Institute, Dr Yeong-Shiong Chiew at Monash Malaysia, Dr Thomas Desaive at Liege University in Belgium, and Professor Bernard Lambermont and Professor Philippe Morimont at CHU de Liege Hospital ICU.
Prof Chase is Deputy Director of the New Zealand MedTech Centre of Research Excellence and the MedTech Spearhead leader for the National Science Challenge, Science for Technological Innovation (SfTI), and acknowledges their support in helping get this concept off the ground.
