Patients treated in ICUs often begin medical care with no evidence of cognitive impairment but leave with deficits that persist for at least a year and are similar to those seen in patients with traumatic brain injury or mild Alzheimers disease, according to a study.
Researchers with the ICU Delirium and Cognitive Group at Vanderbilt University in Nashville, Tenn., studied 821 adults with respiratory failure, cardiogenic shock or septic shock. As published Oct. 3 in the New England Journal of Medicine, they found that 74% of the study cohort developed delirium in the hospital.
Delirium consistently has been shown to be associated with higher mortality, but this large study demonstrates it is associated with long-term cognitive impairment in ICU survivors as well, the authors wrote. At three months, 40% of patients in the study had global cognition scores similar to patients with moderate TBI, and 26% scored similar to patients with AD.
Deficits occurred in both older and younger patients, regardless of whether they had coexisting illness, and persisted to 12 months, when 34% and 24% still had scores similar to TBI and AD patients, respectively.
A longer duration of delirium independently was associated with worse global cognition and worse executive function at three and 12 months. Use of sedative or analgesic medications was not consistently associated with cognitive impairment at three and 12 months.
Regardless of why you come in to an ICU, you have to know that on the back end of your critical care, you are very likely to be suffering cognitively in ways similar to a TBI patient or an AD patient, except that most of the medical profession doesnt even know that this is happening and few around you suspect anything, leaving most to suffer in silence, Wes Ely, MD, the studys senior author and a professor of Medicine, said in a news release.
Ely said at least some component of this form of brain injury may be preventable through efforts to shorten the duration of delirium in the ICU by using careful delirium monitoring and management techniques, including earlier attempts at weaning from sedatives and mobility protocols that can save lives and reduce disability.
Even after the patient leaves the hospital, we think that cognitive rehabilitation might be helpful to somebody like this, and we have some early preliminary data supporting this, Ely said.
Study abstract: www.nejm.org/doi/full/10.1056/NEJMoa1301372