While the after-effects of mechanical ventilation vary greatly from patient to patient, research shows that health tends to decline over time.

A study published this month in Lancet Respiratory Medicine, followed patients in 16 countries who were on mechanical ventilation for more than two weeks to see how they would fare. About 70% left the hospital alive, with only half able to breathe on their own, researchers noted. A year later, about 60% of those patients had died, Emily Damuth and Stephen Trzeciak, critical care specialists at Cooper University Hospital, found. There was no update on the 40% who lived.

Still, the results differed for each individual; older patients with organ failure are more likely to do poorly than a healthier patient, said Jacob Gutsche, a University Pennsylvania critical-care physician. In fact, 80% of patients went to a long-term care facility after being released from the ICU.

Prolonged dependence on mechanical ventilation is an “emerging public health problem” and is growing, Damuth and Trzeciak stated. Between 5% and 10% of patients needed a ventilator for more than two weeks.

Being on a mechanical ventilator makes it nearly impossible for patients to talk or eat, thereby providing a poor-quality life, Danmuth said. However, most people would consent to a 40% survival rate and other risks, and even more are open to the idea of machine assistance just to stay alive, Gutsche explained.

Liberation, the process of improving survival rates and getting patients off ventilators sooner, needs to be further researched, said Jeremy Kahn, who studies critical-care medicine and health policy at the University of Pittsburgh.