Impaired cerebrovascular autoregulation in patients with severe sepsis and sepsis-associated delirium

Patrick Schramm, Klaus Klein, Lena Falkenberg, Manfred Berres, Dorothea Closhen, Konrad J Werhahn, Matthias David, Christian Werner, Kristin Engelhard
2012 Critical Care  
Sepsis-associated delirium (SAD) increases morbidity in septic patients and, therefore, factors contributing to SAD should be further characterized. One possible mechanism might be the impairment of cerebrovascular autoregulation (AR) by sepsis, leading to cerebral hypo-or hyperperfusion in these haemodynamically unstable patients. Therefore, the present study investigates the relationship between the incidence of SAD and the status of AR during sepsis. Methods: Cerebral blood flow velocity was
more » ... measured using transcranial Doppler sonography and was correlated with the invasive arterial blood pressure curve to calculate the index of AR Mx (Mx>0.3 indicates impaired AR). Mx was measured daily during the first 4 days of sepsis. Diagnosis of a SAD was performed using the confusion assessment method for ICU (CAM-ICU) and, furthermore the predominant brain electrical activity in electroencephalogram (EEG) both at day 4 after reduction of sedation to RASS >-2. Results: 30 critically ill adult patients with severe sepsis or septic shock (APACHE II 32 ± 6) were included. AR was impaired at day 1 in 60%, day 2 in 59%, day 3 in 41% and day 4 in 46% of patients; SAD detected by CAM-ICU was present in 76 % of patients. Impaired AR at day 1 was associated with the incidence of SAD at day 4 (p = 0.035). Conclusions: AR is impaired in the great majority of patients with severe sepsis during the first two days. Impaired AR is associated with SAD, suggesting that dysfunction of AR is one of the trigger mechanisms contributing to the development of SAD.
doi:10.1186/cc11665 pmid:23036135 pmcid:PMC3682283 fatcat:aqvupsk25vdvffa5v6upwom7am