Critically Ill Patients with COVID-19 Pneumonia Requiring Continuous Renal Replacement Therapy with oXiris® Membrane in a Third-Level Hospital in Northeast Mexico.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic represented a global public health problem with devastating consequences that have challenged conventional medical treatments. Continuous renal replacement therapy (CRRT), based on a spectrum of modalities and dialysis membranes, can modify cytokine storms, and improve the clearance of inflammatory factors. As severe COVID-19 can lead to acute kidney injury (AKI) requiring RRT, most patients require more than one extracorporeal organ support at this point. This is due to complications that lead to organ dysfunction. The aim of our study was to assess renal recovery and survival while use of the oXiris membrane, as well as a decrease in vasopressors and hemodynamic parameters. METHODS: This was a retrospective, observational study. The population included adult patients (aged >18 years) with a real-time PCR COVID-19 positive test, admitted to the intensive care unit (ICU) with AKI KDIGO 3, which required CRRT, in a hospital in northern Mexico. The primary outcomes were renal recovery and survival, and the secondary outcomes were a decrease in the vasopressor requirements and changes in the hemodynamic parameters. RESULTS: Thirteen patients were included from January 2020 to August 2021, all of whom met the inclusion criteria. oXiris, an AN69-modified membrane, was used for blood purification and cytokine storm control in all the patients. The primary outcome, renal recovery, and survival were observed in 23% of the patients. The secondary outcome was a decrease of 12% in the use of noradrenaline in the first 24 h of CRRT initiation with oXiris, in addition to a decrease in creatinine and C-reactive protein levels in all patients. DISCUSSION: The use of the oXiris membrane in patients with severe COVID-19 improved hemodynamic parameters, with 23% of the patients achieving renal recovery. The decrease on the requirement of vasopressors in the overall patients in the first 24 h of CRRT with oXiris was achieved. The mean decrease was of 12%, accompanied by a decrease in inflammatory markers. There is literature on the benefit of CRRT with a modified AN69 membrane in Mexico; however, studies in this regard are scarce, and our research provides valuable information on our experience in this field.

Kidney Replacement Therapies and Ultrafiltration in Cardiorenal Syndrome.

BACKGROUND: Some patients with cardiorenal syndrome 1 and congestion exhibit resistance to diuretics. This scenario complicates management and is associated with a worse prognosis. In some cases, rescue treatment may be considered by starting kidney replacement therapies or ultrafiltration. This decision is complex and necessitates a profound understanding of these techniques and the pathophysiology of this syndrome. These modalities are classified into continuous, intermittent, and ultrafiltration therapies, each with its own advantages and disadvantages that are pertinent in selecting the optimal treatment. SUMMARY: In patients with diuretic-resistant cardiorenal syndrome, extracorporeal ultrafiltration and kidney replacement therapies have the potential to relieve congestion, restore the neurohormonal system, and improve quality of life. KEY MESSAGES: (i) In cardiorenal syndrome, the resistance to diuretics is common. (ii) Extracorporeal ultrafiltration and renal replacement therapies are rescue options that may improve the management of these patients. (iii) Better understanding of these modalities will help the development of new devices which are friendlier, safer, and more affordable for patients in these clinical settings.

Acute Kidney Injury and Intestinal Dysbiosis.

Within the multiple communication pathways of the intestine-kidney axis, one of the most important pathways is the interaction between the commensals of the intestinal microbiome, through the production of short-chain fatty acids, and the segments of the nephron. These interactions maintain a perfect environmental balance. During AKI, there are negative repercussions in all organs, and the systemic interconnection is related in part to the intense inflammation and the uremic environment that this syndrome generates. For example, in the intestine, the microbiome is severely affected, with a decrease in benign bacteria that promote anti-inflammatory effects and an increase in negative, pro-inflammatory bacteria. This scenario of intestinal dysbiosis widens the inflammatory loop that favors worsening kidney function and the probability of dying. It is possible that the manipulation of the intestinal microbiome with probiotics, prebiotics and symbiotics is a reasonable therapeutic goal for AKI.