NASHVILLE — Staying in an intensive care unit is bad for your brain, according to a study by Vanderbilt University researchers, who determined that mental loss persists for as long as a year afterward.
Results of the study published Wednesday in The New England Journal of Medicine indicate that a third of patients suffer mental deficits akin to moderate traumatic brain injury and about a quarter of them have impairments similar to a mild stage of Alzheimer's disease. Hospitals need to do a better job of keeping ICU patients alert, getting them out of their beds when possible and recognizing that drug-induced comas can do more harm than good, according to the study's authors.
"Historically, we take care of all the other organs but we ignore the brain," said Dr. Pratik Pandharipande, a Vanderbilt professor of anesthesiology and critical care, who was the study's lead author.
The longer a patient suffers from delirium while in the hospital, the higher the risk for dementia once discharged, the study found. The practice of putting critically ill patients into drug-induced comas can lengthen delirium.
"In a nutshell, the simplified version of what these hospitals can be doing is they can make a culture shift in how they handle their sickest patients in the ICU," said Dr. Wes Ely, the senior author of the study and Vanderbilt professor of critical care. "Instead of keeping them in drug-induced comas, they can keep them awake and alert even though they are on life support."
The study tracked patients admitted to ICUs between March 2007 and May 2010 at Vanderbilt University Medical Center and Saint Thomas West Hospital in Nashville. A total of 382 patients underwent cognitive testing a year after being discharged for signs of dementia.
Age was not a significant factor for the loss in mental abilities, according to the study, which also found similar results in patients 49 and younger.
Carl Pangman, 44, a Vanderbilt ICU patient, is just as much at risk for mental loss as someone in his 60s. Ely met with Pangman this week, asking him questions about his pain level and asking him to denote numbers with his fingers.
"We now know that making them not remember actually increases post-traumatic stress disorder and long-term cognitive impairment," Ely said. "The first thing we can do is keep them comfortable — no question — and relieve pain. Once the pain is thought to be under control, do not induce a deeper degree of sedation."
Deep sedation was associated with worse cognitive scores three months after discharge from a hospital.
Among patients 49 and younger, about one in five exhibited dementia similar to mild Alzheimer's — with one big difference. While Alzheimer's disease primarily affects memory, "long-term cognitive impairment after critical illness tended to affect multiple cognitive domains," the article in the medical journal states.
Pandharipande said patients need careful monitoring for cognitive disabilities after an ICU stay.
"We as health care providers need to be aware of this when patients come to us with memory problems, with problems managing their finances, etc., and not blow it off as saying, 'This is all going to get better,' because we really don't know."
The study was supported by grants from the National Institutes of Health and Veterans Affairs.