The occurrence of delirium is severely underestimated by intensivists and intensive care unit nurses during daily ICU care

Introduction

Patients improve faster in the ICU if sedatives are stopped as soon as possible with inherent occurrence of sleeping disorders, and delirium, which could compromise the recovery process and prolong the ICU stay. We investigated whether intensivists and ICU nurses could clinically identify the presence of delirium in ICU patients during daily care.

Methods

All patients in a 3-month period who stayed >48 hours in the ICU were evaluated daily for the presence or absence of delirium by treating intensivists and ICU nurses responsible for daily care. Patients were evaluated independently for the occurrence of delirium by a trained group of ICU nurses who were not involved in the daily care of the patients under study. Since communication with ventilated patients is compromised due to the inability to speak, a specific scoring system was used (confusion assessment method for the intensive care unit (CAM-ICU)), which has been developed for the evaluation of the presence of delirium. Delirium as judged present by this CAM-ICU correlates well with a DSM-IV delirium diagnosis by a trained psychiatrist. Values are expressed as the median and interquartile range (IQR).

Results

During the study period, 46 patients (30 males, 16 females), age 73 (IQR = 64–80) years with an ICU stay of 6 (4–11) days were evaluated. CAM-ICU scores were obtained during 481 patient-days. Considering the CAM-ICU as the gold standard, delirium occurred in 50% of the patients with a duration of 3 (1–9) days. Days with delirium were poorly recognized by doctors (sensitivity = 29.8%; specificity = 99.7%; PPV = 99.6%) and ICU nurses (sensitivity = 35.6%; specificity = 97.8%; PPV = 84%). Patients with a delirium were longer on the ventilator (6 (4–25) days), and had a longer ICU (9 (6–26) days) and hospital stay (29 (21–41) days) than those without delirium during their ICU stay (4 (1–6), P = 0.01; 5 (3–8), P = 0.002; and 19 (7–30), P = 0.01), respectively. APACHE II and SAPS II scores were comparable in both groups.

Conclusion

Delirium is badly recognized in the ICU by intensivists and ICU nurses. In view of the impact of delirium on ICU and hospital stay, more attention should be paid to the implementation of a delirium screening instrument during daily ICU care.