Dr. Jack Feldman

And so we're doing it every five minutes in order to maintain the health of our lung.

In the early days of mechanical ventilation, which was used to treat polio victims who had weakness of their respiratory muscles, they'd be put in these big steel tubes.

And the way they would work is that the pressure outside the body would drop

that would put an expansion pressure on the lungs, excuse me, on the ribcage.

The ribcage would expand, and then the lung would expand.

And then the pressure would go back to normal, and the lung and ribcage would go back to normal.

But there was a relatively high mortality rate.

It was a bit of a mystery.

And one solution was to just give bigger breaths.

I gave bigger breaths, and the mortality rate dropped.

And it wasn't until, I think it was the 50s,

where they realized that they didn't have to increase every breath to be big.

What they needed to do is every so often they need to have one big breath.

So you have a couple of minutes of normal breaths and then one big breath, just mimicking the physiological size.

And then the mortality rate drops significantly.

And if you see someone on a ventilator in the hospital,

If you watch, every couple of minutes that you see the membrane move up and down, every couple of minutes there'll be a super breath and that pops it open.

So there are these mechanisms for these physiological sighs.

So just like with the collapse of the lungs where you need a big pressure to pop it open, it's the same thing with the alveoli.

You need a bigger pressure and a normal breath is not enough.