During Surgery
If you have general anesthesia during surgery, you'll likely be connected to a ventilator. The medicines used to induce anesthesia can disrupt normal breathing. A ventilator helps make sure that you continue breathing during surgery.
After surgery, you may not even know you were connected to a ventilator. The only sign may be a slight sore throat for a short time. The sore throat is caused by the tube that connects the ventilator to your airway.
Once the anesthesia wears off and you begin breathing on your own, the ventilator is disconnected. The tube in your throat also is taken out. This usually happens before you completely wake up from surgery.
However, depending on the type of surgery you have, you could stay on a ventilator for a few hours to several days after your surgery. Most people who have anesthesia during surgery only need a ventilator for a short time though.
For Impaired Lung Function
You may need a ventilator if a disease, condition, or other factor has impaired your breathing. Although you might be able to breathe on your own, it's very hard work. You may feel short of breath and uncomfortable. A ventilator can help ease the work of breathing. People who can't breathe on their own also use ventilators.