Systemic inflammation and sepsis cause multi organ failure including severe neurologic impairment in the course of disease. Neurologic failure typically presents as critical-illness-polyneuropathy/-myopathy and septic encephalopathy during sepsis and is associated with an increased mortality rate.

Clinical parameters to determine the neurologic entities during the course of sepsis are heterogeneous. Further research for an association of clinical parameters and the patients' outcome is needed.

The study aims toward differences in the clinical and neurological outcome of surgical and non-surgical septic patients in comparison to non-septic patients on ICU. The aim of the study is to identify clinical and diagnostic outcome predictors in septic patients.

All patients with severe sepsis and septic shock and fulfilling the inclusion criteria should be screened for the study on two surgical (septic surgical patients), one medical intensive care unit (septic non-surgical patients) and one neurological intensive care unit (non-septic patients) at the university hospital of Rostock, Germany.

The inclusion of patients will be started if written informed consent was obtained from all participants or their representatives (if direct consent could not be obtained).

The aim of the study is to determine differences in the neurological outcome of surgical and non-surgical septic patients (incidence, severity and length of critical-illness-polyneuropathy/-myopathy and septic encephalopathy). The main interest of the study is to find parameters associated with an improved neurological outcome in septic patients within an observation time of 100 days.

The main criterion is the incidence, severity and length of septic encephalopathy and critical-illness-polyneuropathy and -myopathy on days 7 and 28.

From all patients basic demographic data, illness severity scores (APACHE-II, SOFA) and delirium scores for the assessment of septic encephalopathy (CAM-ICU, ICDSC), laboratory, cerebrospinal fluid and microbiological results, electrophysiological (electroneurography(ENG)), electroencephalography (EEG), cranial MRI results, pre-morbidity data and clinical outcome for the study cohort will be recorded. At the days 1, 3, 7 and 28 the patients will be screened for clinical and laboratory/immunological data: hemodynamic, inflammation, coagulation, organ function, blood parameters including cytokines.

Neurological examination and EEG will be performed within 24 hours after the beginning of the study. Examination of liquor cerebrospinalis will be performed within 24-48 hours and cranial MRI between day 3 and 7 after the inclusion of the patient. ENG will be done earliest one week after the beginning of the study.

Inclusion Criteria:

• Fulfilling criteria for severe sepsis or septic shock

Exclusion Criteria:

• Diagnosis of cerebrovascular disease (pre-existing)
• Advanced dementia
• Diagnosis of pre-existing other neuromuscular disease
• High-dose glucocorticosteroid therapy (> 300 mg Hydrocortisone/die)
• Pre-existing renal replacement therapy
• Coagulation disorder with bleeding
• Frequent administration of neuromuscular blocking agents (> 3 times/week)

All patients with severe sepsis and septic shock and fulfilling the inclusion criteria should be screened for the study on two surgical (septic surgical patients), one medical intensive care unit (septic non-surgical patients) and one neurological intensive care unit (non-septic patients) at the university hospital of Rostock, Germany.