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The Manual's Editorial Staff

Reviewed/Revised Aug 2022 | Modified Sep 2022
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Ventilation is the same thing as breathing. It's the movement of air into and out of your lungs. Sometimes your breathing needs to be assisted by a ventilator.

What is a ventilator?

  • A ventilator is a machine that breathes for you—the process is called mechanical ventilation

  • A ventilator uses pressure to push air into your lungs

  • Usually the air is mixed with pure oxygen so it contains more oxygen than what's in room air

  • Doctors set the ventilator to control how often it gives you a breath and how much air you get

  • A ventilator can do all your breathing or just help out

Why does someone need a ventilator?

You need a ventilator if:

  • You're not able to breathe

  • Your breathing is too weak

You might not be breathing or have weak breathing for many reasons, including:

How does a ventilator work?

There are 2 main ways ventilators get air into your lungs:

  • Through a plastic tube put into your windpipe (called invasive ventilation because the tube "invades" your body)

  • Through a tight-fitting face mask (called noninvasive ventilation)

Invasive ventilation is used for people who need the most help with their breathing. Doctors can put the tube into the windpipe through:

  • Your mouth (most common)

  • Your nose

  • A small cut in the front of your neck (called a tracheostomy)

You'll get a tracheostomy if you need to be on a ventilator for more than a few days. A tracheostomy tube goes into your windpipe below your voice box. That way the tube won't push on your vocal cords, which can damage them.

Having a tube in your nose or throat is uncomfortable, so you'll get medicine in your veins to keep you relaxed and comfortable.

Noninvasive ventilation is used if you're awake and breathing pretty well on your own but need some help. If you're unconscious or very weak, noninvasive ventilation doesn't work. That's because your tongue falls back into your throat and air from a mask can't get through.

With both invasive and noninvasive ventilation, doctors program the ventilator so you get the right amount of oxygen and the right number of breaths. The ventilator can tell if you're able to breathe a little on your own and adjusts to just assist your breathing.

What problems can happen with a ventilator?

Problems you might have from a ventilator include:

Will I have trouble getting off the ventilator?

You may have heard that some people have trouble getting off a ventilator. There are 2 possible reasons for that:

  • The original problem didn't get better

  • Breathing muscles became weak from not being used

Ideally, you'll need a ventilator just for a little while until your problem goes away. For example, an overdose wears off or treatments stop an asthma attack. But some problems don't go away. For example, a person who has brain damage from a stroke or severe injury may never get better enough to come off the ventilator.

If you're on a ventilator for a long time, your breathing muscles may get weak. In this case, doctors build up your muscles by having you breathe on your own for a little while every day. Your breathing will gradually get stronger until you don't need the ventilator anymore.

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