British Columbia

SFU professor's invention to help recovery of ventilator patients approved for emergency use in U.S.

Prof. Andy Hoffer's therapy system uses electrical stimulation to strengthen the diaphragm, which becomes weaker when a ventilator takes over to help a patient breathe.

System uses electrical stimulation to strengthen diaphragm, which can weaken with prolonged ventilator use

The diaphragmatic pacing therapy system has been authorized by the U.S. Food and Drug Administration under an Emergency Use Authorization during the COVID-19 pandemic to help patients recover after prolonged ventilator use. (Lungpacer Medical Inc.)

A Simon Fraser University professor's invention submitted for patents 13 years ago has been granted approval for emergency use by the U.S. Food and Drug Administration during the COVID-19 pandemic to help wean critically ill patients off ventilators.

The diaphragmatic pacing therapy system strengthens the diaphragm, which becomes weaker when a ventilator takes over to help a patient breathe.

It was developed by Prof. Andy Hoffer, who began studying diaphragm properties after his mother developed pneumonia and ended up on a ventilator in hospital more than a decade ago.

"She was never able to breathe well again. She died in hospital," said Hoffer, a professor at SFU's Department of Biomedical Physiology and Kinesiology.

Hoffer spoke to the relatives of other patients in intensive care and realized they had similar problems weaning off ventilators. He found that while a patient is on a ventilator, their diaphragm — the main muscle that helps people breathe — deteriorates.

"If a patient is on a ventilator for more than a day or two, the diaphragm really atrophies very fast. It can atrophy to half its size in three days of ventilation," explained Hoffer.

Consequently, "about 30 per cent of patients on ventilators fail to wean because their capacity to breathe on their own is less than minimum."

Andy Hoffer is a professor at Simon Fraser University's Department of Biomedical Physiology and Kinesiology. (Simon Fraser University)

Hoffer came up with the idea to use electrical stimulation to strengthen the diaphragm while a patient is on a ventilator.

"Electrical stimulation, if properly applied, is a very powerful way to rebuild muscles or to build up muscles," he said.

Hoffer says he received help from SFU to develop the idea and eventually formed a company, Lungpacer Medical, which is taking the therapy system to global markets.

The therapy is administered through a catheter that delivers both fluids and medications and also incorporates electrodes that stimulate the diaphragm muscle. 

The system had been undergoing clinical trials in more than 40 hospitals in Europe and the U.S. when they were put on hold due to the COVID-19 pandemic.

But it was brought back into the spotlight as ventilator use increased due to the symptoms of COVID-19, which include severe respiratory problems.

Hoffer said the FDA approved the system for emergency use in hospitals on April 14, to help severely ill patients who are having difficulties recovering after prolonged ventilator use.

He said clinical trials are expected to eventually resume and he hopes the product will be cleared for regular use in the U.S. and Canada.

Hoffer said the diaphragm can be a key aspect to recovery for patients with respiratory issues and the muscle shouldn't be underestimated.

"It never rests from your first breath to your last breath," he said.

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  • A previous version of this story mistakenly stated that Prof. Andy Hoffer patented the diaphragmatic pacing therapy system 13 years ago. In fact, patents for the therapy were submitted 13 years ago and granted seven years ago.
    May 08, 2020 3:17 PM PT


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