In recent years, many studies have pointed out that bacterial toxin storm and cytokine storm are the main causes of patients with septic shock and multiple organ dysfunction. Endotoxins are the main mediators of gram-negative bacteria causing systemic inflammation and sepsis. Endotoxins can interact with Toll- Like receptor 4 (TLR4) binding and trigger cytokine storms. The triple-effect blood purification filter (oXiris) has been proven to remove endotoxins, cytokines and urinary toxins, and it has the opportunity to improve shock in patients with sepsis. We hypothesize that blood purification using the three-effect filter can shorten the duration and severity of shock in patients with severe septic shock and reduce the organ damage by removing endotoxin, cytokine and urinary toxins. The primary aim of this study is to investigate the effect of blood purification using the three-effect filter on shortening the duration of septic shock. Other exploratory variables include the reduction of severity of organ damage and other clinical outcomes and prognosis.

This multi-center, prospective, randomized controlled trial will enroll patient with septic shock. After the screening of eligibility and obtaining the signed informed consent, the enrolling patients will be randomly assigned to the following two groups: the control group and the blood purification group. In the control group, patients will receive the treatments for septic shock according to the Surviving Sepsis Campaign guidelines. If the primary care intensivist decides that continuous renal replacement therapy (CRRT) is indicated, the patient will receive CRRT with regular continuous veno-venous hemofiltration filter. In the blood purification group, patients will receive the treatments for septic shock according to the Surviving Sepsis Campaign guidelines. In addition, these patients will receive blood purification treatment with oXiris filter within two hours after enrollment. The blood purification treatment will be continued for up to 72 hours as needed, and a new oXiris filter will be replaced every 12 to 24 hours. If the primary care intensivist decides that continuous renal replacement therapy (CRRT) is indicated at 72h after blood purification, the patient will receive CRRT with regular continuous veno-venous hemofiltration filter.

The following information will be recorded: diagnosis of intensive care unit admission, past medical history, severity of illness, vital signs, blood pressure, infusion doses of vasopressors and inotropes, fluid balance, sequential organ failure assessment score, daily urine output, lactate, creatinine, and other regular laboratory data. Blood sample will be obtained for analysis of the levels of procalcitonin, cytokines (IL-6, IL-10, HMGB-1 and TNF-α), vascular endothelial cell injury biomarker, kidney injury biomarker and intestinal injury biomarkers.

The primary outcome is the difference of the duration of vasopressor between the two groups. The secondary is the proportion of reduction in vasoactive-inotropic score at 72h between the two groups. Other exploratory variables include the the proportion of reduction in vasoactive-inotropic score at other time points, the serum level of cytokines and organ injury biomarkers, and clinical outcomes between the two groups.