IISc developing ventilator to save coronavirus patients

"A team of scientists and engineers are building a prototype of an electro-mechanical ventilator using local components," said the over-century-old institute in the statement.

Even as hundreds of patients grapple with the Covid-19 pandemic across the country and hospitals set to face shortage of the life-saving instrument, the team has designed the prototype based on guidelines of the British medicine and healthcare products regulatory agency.

"As local manufacturers are unbale to source key components like sensors and flow controllers from overseas due to disruption in global supply chain, we are using only local parts made in India," said the institute's principal research scientist T.V. Prabhakar.

The project is undertaken by the department of electronic systems engineering at the institute.

"We are assembling the ventilator for use free of cost. The prototype will be ready for trials in the next couple of weeks. We hope by this month-end, manufacturers can make them and scalp up soon," said associate professor and project coordinator Gaurab Banerjee.

Though about 40,000 ventilators are available across the country, they will be required in thousands if the virus cases spike rapidly.

"Patients with severe Covid infection have damaged lungs that gasp for oxygen. When they are put on a ventilator, the machine enables lung function, feeding them with air and oxygen to fight the virus," said Prabhakar.

A well-designed ventilator will have sensors and actuators that allow doctors to set the volume and pressure of gas delivered to the patient precisely, which depends on the severity of their illness.

To store and mix air and oxygen, for instance, some component makers reused sedimentation tanks found in household RO water purifiers.

"Our mixing process has parallels to those in gas turbines and industrial burners, where the ratio of fuel and oxidizer is carefully controlled," Aerospace engineering department's assistant professor Pratisha Panda said.

To check pressure levels, sensors similar to those are used to detect air pressure in car tyres.

"Controlling the pressure at which gas is pumped into the patient's lungs is crucial, akin to how using an industrial pressurised hose to water plants instead of a garden hose can cause severe damage," the faculty members warned the doctors.

The team is also developing a flow rate sensor, which shows how much air is flowing into a patient's lungs.

"By using concepts of fluid and gas dynamics, we are able to estimate and control pressure, volume and oxygen concentration of the air delivered to the patient," said team member Duvvuri Subrahamanyam.

The team is taking inputs from doctors to simplify the interface and build a dashboard preloaded with approved settings.

The dashboard will allow it to operate in an emergency by technicians or nurses.

"They will have to press a button that says pneumonia or Acute Respiratory Distress Syndrome (ARDS) and all the settings will come up by default within a certain range," said Banerjee.

"We are working with manufacturers to check components required for including them in the final design," said team member Manish Arora.

State-run organisations like Bharat Heavy Electricals Ltd (BHEL) have expressed interest in supporting mass production.

"The institute's centre for nano science and engineering has provided the team with local oxygen and pressure sensors," Arora added.