Acute kidney injury (AKI) is a common complication in critically ill patients. Multiple studies have reported evidence that the main cause of ARF is sepsis, as part of the Multiple Organ Dysfunction Syndrome: up to 50% of septic patients develop acute renal failure.

RRT continues to be the standard management for severe acute renal failure, especially in its continuous modality and applied to the septic patient, generally with hemodynamic instability.

The presence of SA-AKI (sepsis-associated acute kidney injury) is associated with short-term and long-term adverse events, which include: prolonged hospital stay, the development of chronic kidney disease (CKD), increased cardiovascular risk and increased risk of death. Its presence is even considered a factor with an independent association with mortality and has a higher fatality rate than ARF developed by another etiology.

Different clinical studies have been developed based on the addition of hemoadsorption membranes to RRT that, although they have not shown significant differences in the reduction of mortality, have impacted secondary outcomes such as the reduction of pro-inflammatory cytokines, decrease in vasopressor support requirements, decrease in serum lactate, significant improvement in the SOFA score, improvement in oxygenation indices and decrease in hospital stay. These benefits are presented without reports of adverse events associated with its use.

The oXiris® filter was recently developed: a single high permeability membrane capable of removing cytokines and endotoxins during renal support with the addition of antithrombotic properties. The experience of its use is limited to in vitro studies, case reports, retrospective cohorts and an RCT that provide consistent evidence of its benefits.

A longitudinal, bi-directional, observational analytical study is proposed. A case-control study nested in a dynamic cohort will be developed to determine the effect of the use of hemofiltration with a cytokine removal filter (oXiris®) on the decrease in mortality at 28 days of patients with acute kidney injury induced by sepsis. (SA-AKI), as well as the dose of vasopressor support, oxygenation parameters and inflammatory markers.

Inclusion Criteria:

• Patients who enter the Intensive Care Unit of the CES Clinic during the recruitment period with:
• Diagnosis of septic shock of any origin according to the definition of the Sepsis-3 consensus.
• Acute renal injury according to the KDIGO 2012 classification that requires continuous renal replacement therapy and that its origin is presumed to be septic origin.
• In invasive ventilatory support.
• Informed consent previously filled out by a guardian.

Exclusion Criteria:

• Patients under 18 years of age and women in pregnancy or postpartum will be excluded.
• Chronic kidney disease that requires RRT on an outpatient basis before admission to the ICU.
• Contraindication to the use of heparins or another anticoagulant
• Dissent to escalate therapeutic measures
• Terminal or irrecoverable condition according to the criteria of the specialist in critical medicine and intensive care

Patients admitted to the institutional Intensive Care Unit (CES Clinic) with acute kidney injury induced by sepsis and requiring renal replacement therapy.