If a patient has been in a complicated admission to intensive care and is more unstable, such as after a car accident, major surgery, or had a head, brain, or heart injury, coming off of the ventilator might be a little more difficult. The longer ventilation is required, the higher the risk that complications can arise. Once the patient is shown to have the strength to breath by themselves and is stable, they may be able to be taken off the ventilator after 3-7 days.