Critical care patients are at a high risk of developing delirium and impaired cognitive function 3 and 12 months after their ICU stay. In this study the aim is to try to elucidate the pathophysiology behind delirium in the ICU and subsequent development of cognitive dysfunction in ICU survivors.

Biomarkers in cerebrospinal fluid (CSF) will be analysed in patients with and without delirium in the ICU. Samples will also be taken 3 and 12 months after the ICU-stay. CSF will also be obtained in healthy age- and sexmatched controls undergoing surgery.

Critical care patients are at a high risk of developing delirium, a form of acute brain dysfunction, and may develop impaired cognitive function 3 and 12 months following their ICU stay.

In this study the aim is to try to elucidate the pathophysiology behind delirium in the ICU comparing patients with and without delirium and possible development of cognitive dysfunction in ICU survivors. Neuroinflammatory markers and markers of structural damage in cerebrospinal fluid (CSF) will be analysed in patients with and without delirium assessed with the CAM-ICU (Confusion Assessment Method) test in the ICU. CSF samples will also be taken in ICU-survivors, 3 and 12 months after the ICU-stay. For comparison CSF will be obtained in healthy age- and sexmatched controls undergoing surgery in spinal anesthesia.

Inclusion Criteria:

• Patients admitted to ICU for acute respiratory, septic and/or circulatory chock

Exclusion Criteria:

• Abnormal coagulation
• Recent exposure to intensive care
• Patients unable to assess for delirium
• Patients difficult to follow up
• Patients expected to live less than 24 hrs
• Patients with known cognitive dysfunction based on medical records or relatives report
• Abnormal coagulation

Intensive care patients