The ongoing coronavirus pandemic has drawn attention to a vital piece of lifesaving medical equipment: a ventilator.
You might not immediately know what it is — but you would have seen them. In hospitals, online or in television medical dramas.
So what exactly is it, and why are they needed right now more than ever?
What’s a ventilator?
The ventilator is effectively a breathing machine, or the most common component of a “life support” machine.
It’s connected to a tube that goes into the mouth, past the vocal chords and down into the windpipe (a process called intubation, for those playing at home).
Professor of Respiratory Medicine at the University of Sydney, Greg King, said it helped a patient by doing either all of their breathing or some of it.
“If breathing fails, the patients obviously dies. So you can think of ventilation as very much a life-support system,” he said.
Is it the same as a respirator?
No, it’s not, even though the terms are sometimes used interchangeably.
Professor King said the term “respirator” meant different things to different people.
Sometimes it’s used to describe the face masks worn by medical staff to stop them breathing in viral particles.
But it’s also used to describe things like the underwater breathing apparatus scuba divers use.
For the sake of clarity, it’s a term best avoided.
How is a ventilator used to treat coronavirus?
It is mainly used for the very serious cases of COVID-19.
Anaesthetist Dr Simon Macklin from the Australian Medical Association (SA) said in those cases, patients were weakened to the stage where they have difficulty getting enough oxygen into their lungs and enough carbon dioxide out.
“When that happens patients often have to work extremely hard to try to maintain adequate oxygen levels,” Dr Macklin said.
“Often patients become so fatigued by this process they’re unable to do it on their own.”
They are then given drugs and placed into an artificial coma, before being connected to a ventilator through the tube we mentioned earlier.
The ventilator then does the breathing for the patient.
Are there different types of ventilators?
In hospitals, there are two types of ventilators that are used.
The ones we’re talking about at the moment for patients with coronavirus are Intensive Care Unit ventilators. They’re attached to ICU beds, and are considered the “gold standard” of ventilators.
The other ventilators are used in operating theatres for major surgery. They’re like one of the original models of the iPhone. Still good — but with fewer features.
Dr Macklin said the intensive care ventilators are specifically designed to cope with “very sick patients with very sick lungs” while the operating theatre ventilators aren’t as sophisticated.
President of the Australian Society of Anaesthetists, Dr Suzi Nou, said in critical cases, ICU ventilators were used because there were a wide range of settings you could plug into the machine to minimise risk to the patient.
“When I’ve had sick patients in the operating theatre, you can have trouble ventilating them for whatever reason, the patient and the machine are not getting along so well, and then you transfer them into ICU and you put them on a nice ICU ventilator, and it becomes a lot easier.”
Do we have enough ICU ventilators?
At this stage — yes. But the concern is that we will not have enough as the coronavirus outbreak escalates.
“It’s the crystal ball question.” Dr Nou said.
Currently, there are about 2,000 ventilators attached to beds in ICU units around Australia.
The government is looking to double those to 4,000.
Going off global figures, about 5 per cent of coronavirus cases will become critically unwell and will need ICU care.
So based on the way the virus is tracking, doctors are concerned many more than 4,000 people will need to be hospitalised during the pandemic, and require ICU ventilators to help breathing.
But when we talk about shortages, we’re not just talking about the machines.
Ventilators are run by anaesthetic, intensive care and emergency doctors, while the day-to-day, minute-to-minute management of the ventilator is overseen by specifically trained intensive care nurses.
And there are fears that there are not enough critical care staff to use the extra machines when they come into play.
Can other machines be converted to ventilators?
You might have seen stories this week about vets being asked to sacrifice the ventilators used to keep animals breathing, if the number of coronavirus patients needing ventilation exceeds the number of machines now available.
Animal ventilators would need to be cleaned and checked before being used on humans, experts say. (Supplied)
Overseas we’ve also seen engineers make ventilators from snorkelling masks and even ventilator parts out of 3D printers.
Back home, the Government has also flagged it.
It’s currently in talks with car manufacturer Ford about the potential to make machines, while Finance Minister Mathias Corman this week told the Senate that “the states also have processes to convert existing equipment into ventilators.”
The Therapeutic Goods Administration (TGA) on Thursday said it took a “proactive stance” in terms of repurposing alternative devices – like veterinary ventilators.
But are these converted machines going to as good as the fit-for-purpose ICU ventilators?
The short answer to this is no, Professor King said.
“They’re not going to be as effective, as sophisticated as the modern ventilator,” he said.
“But whether that translates to worse outcomes, we don’t know, because a lot of this will also be dependent on the skill of the medical team around it.”
The TGA said that where possible, health care facilities should use approved, conventional ventilators when necessary to support patients with respiratory failure.
But as Professor King notes, sometimes some ventilation is better than no ventilation at all.
Dr Nou said as always, prevention was better than cure, and physical distancing measures were crucial in trying to flatten the curve and reduce the number of critical cases of coronavirus.
“If we could stop this potential tsunami of people needing ventilating support, that would be better than making bits of circuit out of 3D printers.”