No abstract

Delirium, a complication not currently monitored in the ICU setting, is extremely common in mechanically ventilated patients. The CAM-ICU appears to be rapid, valid, and reliable for diagnosing delirium in the ICU setting and may be a useful instrument for both clinical and research purposes.

Objective To test the hypothesis that duration of delirium in the intensive care unit (ICU) is an independent predictor of long-term cognitive impairment after critical illness requiring mechanical ventilation. Design Prospective cohort study. Setting Medical ICU in a large community hospital in the United States. Patients Mechanically ventilated medical ICU patients who were assessed daily for delirium while in the ICU and underwent comprehensive cognitive assessments 3 and 12 months after discharge. Measurements and Main Results Of 126 eligible patients, 99 survived ≥3 months post-critical illness; long-term cognitive outcomes were obtained for 77 (78%) patients. Median age was 61 years, 51% were admitted with sepsis/ARDS, and median duration of delirium was 2 days. At 3-and 12-month follow-up, 79% and 71% of survivors had cognitive impairment, respectively (with 62% and 36% being severely impaired). After adjusting for age, education, preexisting cognitive function, severity of illness, severe sepsis, and exposure to sedative medications in the ICU, increasing duration of delirium was an independent predictor of worse cognitive performance—determined by averaging age- and education-adjusted T-scores from nine tests measuring seven domains of cognition—at 3-month (p = 0.02) and 12-month follow-up (p = 0.03). Duration of mechanical ventilation, alternatively, was not associated with long-term cognitive impairment (p = 0.20 and 0.58). Conclusions In this study of mechanically ventilated medical ICU patients, duration of delirium was independently associated with long-term cognitive outcomes, representing a potentially modifiable predictor of this common public health problem.