Standard renal replacement therapy combined with hemoadsorption in the treatment of critically ill septic patients

The potential role of extracorporeal cytokine removal with CytoSorb® as an adjuvant therapy in Acute Respiratory Distress Syndrome

Management of acute respiratory distress syndrome (ARDS) represents one of the greatest challenges in intensive care and despite all efforts mortality remains high. One common phenotype of ARDS is that of a secondary injury to a dysregulated inflammatory host response resulting in increased capillary congestion, interstitial lung edema, atelectasis, pulmonary embolism, muscle wasting, recurring infectious episodes, and multiple organ failure. In cases of hyperinflammation, immunomodulation by extracorporeal cytokine removal such as the CytoSorb hemoadsorption cartridge could conceptually enhance lung recovery during the early course of the disease. The aim of this narrative review is to summarize the currently available data in this field and to provide an overview of pathophysiology and rationale for the use of CytoSorb hemoadsorption in patients with hyperinflammatory ARDS.

Proteomic changes to immune and inflammatory processes underlie lung preservation using ex vivo cytokine adsorption

Introduction

In recent years, the field of graft preservation has made considerable strides in improving outcomes related to solid organ restoration and regeneration. Ex vivo lung perfusion (EVLP) in line with the related devices and treatments has yielded promising results within preclinical and clinical studies, with the potential to improve graft quality. Its main benefit is to render marginal and declined donor lungs suitable for transplantation, ultimately increasing the donor pool available for transplantation. In addition, using such therapies in machine perfusion could also increase preservation time, facilitating logistical planning. Cytokine adsorption has been demonstrated as a potentially safe and effective therapy when applied to the EVLP circuit and post-transplantation. However, the mechanism by which this therapy improves the donor lung on a molecular basis is not yet fully understood.

Methods

We hypothesized that there were characteristic inflammatory and immunomodulatory differences between the lungs treated with and without cytokine adsorption, reflecting proteomic changes in the gene ontology pathways and across inflammation-related proteins. In this study, we investigate the molecular mechanisms and signaling pathways of how cytokine adsorption impacts lung function when used during EVLP and post-transplantation as hemoperfusion in a porcine model. Lung tissues during EVLP and post-lung transplantation were analyzed for their proteomic profiles using mass spectrometry.

Results

We found through gene set enrichment analysis that the inflammatory and immune processes and coagulation pathways were significantly affected by the cytokine treatment after EVLP and transplantation.

Conclusion

In conclusion, we showed that the molecular mechanisms are using a proteomic approach behind the previously reported effects of cytokine adsorption when compared to the non-treated transplant recipients undergoing EVLP.

Reduction of primary graft dysfunction using cytokine adsorption during organ preservation and after lung transplantation

Despite improvements, lung transplantation remains hampered by both a scarcity of donor organs and by mortality following primary graft dysfunction (PGD). Since acute respiratory distress syndrome (ARDS) limits donor lungs utilization, we investigated cytokine adsorption as a means of treating ARDS donor lungs. We induced mild to moderate ARDS using lipopolysaccharide in 16 donor pigs. Lungs were then treated with or without cytokine adsorption during ex vivo lung perfusion (EVLP) and/or post-transplantation using extracorporeal hemoperfusion. The treatment significantly decreased cytokine levels during EVLP and decreased levels of immune cells post-transplantation. Histology demonstrated fewer signs of lung injury across both treatment periods and the incidence of PGD was significantly reduced among treated animals. Overall, cytokine adsorption was able to restore lung function and reduce PGD in lung transplantation. We suggest this treatment will increase the availability of donor lungs and increase the tolerability of donor lungs in the recipient.

Lung transplantation is hindered by the scarcity of organs and by mortality following primary graft dysfunction. Here, the authors show that cytokine absorption can be used in donor lungs during ex vivo lung perfusion and post-transplant, and leads to restored lung function and reduced primary graft dysfunction in animal models.

Current Status and Future Perspectives on Machine Perfusion: A Treatment Platform to Restore and Regenerate Injured Lungs Using Cell and Cytokine Adsorption Therapy

Since its advent in the 1990′s, ex vivo lung perfusion (EVLP) has been studied and implemented as a tool to evaluate the quality of a donor organ prior to transplantation. It provides an invaluable window of opportunity for therapeutic intervention to render marginal lungs viable for transplantation. This ultimately aligns with the need of the lung transplant field to increase the number of available donor organs given critical shortages. As transplantation is the only option for patients with end-stage lung disease, advancements in technology are needed to decrease wait-list time and mortality. This review summarizes the results from the application of EVLP as a therapeutic intervention and focuses on the use of the platform with regard to cell therapies, cell product therapies, and cytokine filtration among other technologies. This review will summarize both the clinical and translational science being conducted in these aspects and will highlight the opportunities for EVLP to be developed as a powerful tool to increase the donor lung supply.

Adjuvant hemoadsorption therapy in patients with severe COVID-19 and related organ failure requiring CRRT or ECMO therapy: A case series

INTRODUCTION

Severe cases of the COVID-19 are often associated with the development of a fulminant sepsis-like state with a concomitant cytokine release syndrome. Recently, immunomodulating approaches to treat such a hyperinflammation have come into focus, including the use of new extracorporeal organ support therapies such as CytoSorb hemoadsorption designed to remove cytokines and other circulating mediators from blood.

PATIENTS AND METHODS

Thirteen critically ill COVID-19 patients with ARDS who received either ECMO therapy and/or CRRT with concomitant multiple organ failure were included. Hemoadsorption therapy was initiated once the patient had established-or was at high risk of developing-a hyperinflammatory state with marked hemodynamic instability or progressive lung failure. Levels of inflammatory markers, vasopressor requirements, oxygenation, and ventilation parameters were measured, as well as clinically relevant outcome measures.

RESULTS

Combined therapy was associated with a significant reduction in inflammatory mediators, hemodynamic stabilization with a concomitant decrease in requirements for vasoactive substances, and a pronounced improvement in lung function and the need for ventilatory support. Treatment appeared safe and well-tolerated.

CONCLUSIONS

In this case series of SARS-CoV-2 infected patients admitted to the intensive care unit with ARDS, we report effective interleukin (IL)-6 removal, reduced norepinephrine requirement, and improved lung function while receiving adjuvant, extracorporeal hemoadsorption therapy in the context of a multimodal treatment approach. The presented protocol for CytoSorb initiation may be a good foundation for the development of further prospective studies in the field and may eventually also be applied to other forms of hyperinflammatory ARDS.

The Potential Role of Extracorporeal Cytokine Removal in Hemodynamic Stabilization in Hyperinflammatory Shock

Hemodynamic instability due to dysregulated host response is a life-threatening condition requiring vasopressors and vital organ support. Hemoadsorption with Cytosorb has proven to be effective in reducing cytokines and possibly in attenuating the devastating effects of the cytokine storm originating from the immune over-response to the initial insult. We reviewed the PubMed database to assess evidence of the impact of Cytosorb on norepinephrine needs in the critically ill. We further analyzed those studies including data on control cohorts in a comparative pooled analysis, defining a treatment effect as the standardized mean differences in relative reductions in vasopressor dosage at 24 h. The literature search returned 33 eligible studies. We found evidence of a significant reduction in norepinephrine requirement after treatment: median before, 0.55 (IQR: 0.39-0.90); after, 0.09 (0.00-0.25) μg/kg/min, p < 0.001. The pooled effect size at 24 h was large, though characterized by high heterogeneity. In light of the importance of a quick resolution of hemodynamic instability in the critically ill, further research is encouraged to enrich knowledge on the potentials of the therapy.

[Treatment of a Patient with a Pronounced Cytokine Storm in Severe COVID-19 Pneumonia using a Hemoadsorption in Combination with the Administration of tocilizumab]

Despite growing experience due to increasing patient numbers, the intensive care treatment of patients with severe COVID-19 pneumonia continues to be a particular challenge in individual cases, which may also therefore legitimize individualized therapeutic attempts. In this context, the so-called hyperinflammation syndrome characterized by a cytokine storm accompanied by a massive increase in inflammatory markers such as interleukin(IL)-6, represents such a situation. This case report describes the therapeutic approach of using the IL-6-specific antibody tocilizumab in combination with hemoadsorption therapy (CytoSorb) in a 58-year-old male patient with severe COVID-19 pneumonia. The patient suffered a massive clinical deterioration with concomitant Horovitz index of 127 mmHg that occurred on the 6^th day of ventilation. After combined application of the above-mentioned therapeutic approaches, the patient stabilized rapidly paralleled by a significant increase in the Horovitz index, and the possibility of de-escalating the ventilation regimen, which ultimately enabled successful extubation after only 13 days of ventilation. Moreover, the combined treatment was associated with significant hemodynamic stabilization and a consecutive reduction in vasopressor doses, while hyperinflammation could be kept well under control. The incorporation of the hemoadsorber into the therapeutic regimen proved to be safe and straightforward. In conclusion, the combination of CytoSorb therapy and IL-6 blockade by tocilizumab appeared, at least in this case, to be an effective measure to modulate an overshooting immune response in COVID-19 pneumonia with a concomitant clinical improvement in both respiratory and hemodynamic function, and thus could be used as a potential therapeutic option in this clinical picture.