Correlation of Cerebral Hemodynamics and Cerebral Oxygen Saturation with the Prognosis of Patients with Septic Shock: A Prospective Cohort Study

  Objective  The aim of this study was to explore the correlation of the changes of cerebralhemodynamic indexes of the middle cerebral artery and cerebral oxygen saturation withthe prognosis of patients with septic shock.

  Methods  The clinical data of patients with septic shock admitted to the department of Critical Care Medicine of Xiangya Hospital of Central South University from May 2018 to March 2019 were collected. Based on if dead or not within 28 days after the admission, the patients were divided into two groups, the death group and survival group. The general clinical information, arterial and central venous blood gas index immediately after admission into our department and after 6 hours of initial liquid resuscitation, critical cardiac ultrasound indicator, organ function index, indicator of sepsis biomarkers, middle cerebral artery blood flow velocity, dynamic cerebral perfusion index, brain transient congestion response ratio (THRR), and change of cerebral oxygen saturation after 6 hours of initial liquid resuscitation were compared.

  Results  Totally 51 patients with septic shock meeting the inclusive and exclusive criteria were enrolled in this study, 31 male and 20 female, with an average age of (53±13) years and 28-day mortality of 43%. Compared with the survival group, the death group had a higher sequential organ failure assessment (SOFA) (P=0.007), acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score (P=0.026), and peak APACHEⅡ score (P < 0.001). Patients in the death group had a lower oxygenation index (P=0.047) and a higher value of central venous-to-arterial carbon dioxide difference (Pcv-aCO₂) (P=0.044). In addition, the death group showed more impaired dynamic cerebrovascular autoregulation (THRR < 1.09) (P=0.025), lower regional cerebral oxygen saturation (rSO₂) mean (P=0.031), and more patients with mean rSO₂ < 60% (P=0.010). Multivariable Logistic regression analysis showed that the peak APACHE Ⅱ score (OR=1.099, 95% CI: 1.009-1.196, P=0.030), the Pcv-aCO₂ after 6 hours of initial liquid resuscitation (OR=1.320, 95% CI: 1.001-1.742, P=0.050), THRR < 1.09 (OR=4.952, 95% CI: 1.130-21.70, P=0.034), mean rSO₂ < 60% (OR=4.817, 95% CI:1.392-16.663, P=0.013) were independently associated with the mortality.

  Conclusions  The mortality of patients with septic shock is high; impaired dynamic cerebrovascular autoregulation (THRR < 1.09) and mean rSO₂ < 60% among the cerebral hemodynamics and cerebral oxygen saturation indexes are the independent risk factors for predicting the death in 28 days.