Impact of CytoSorb Hemoadsorption on Sedation Requirements in Patients With Severe COVID-19 on Venovenous Extracorporeal Membrane Oxygenation

Hemoadsorption in Organ Preservation and Transplantation: A Narrative Review

Cytokine adsorption can resolve different complications characteristic of transplantation medicine, such as cytokine storm activation and blood ABO and immune incompatibilities. Cytokine adsorption is also performed for the treatment of various life-threatening conditions, such as endotoxic septic shock, acute respiratory distress syndrome, and cardiogenic shock, all potentially leading to adverse clinical outcomes during transplantation. After surgery, dysmetabolism and stress response limit successful graft survival and can lead to primary or secondary graft dysfunction. In this clinical context, and given that a major problem in transplant medicine is that the demand for organs far exceeds the supply, a technological innovation such as a hemoadsorption system could greatly contribute to increasing the number of usable organ donors. The objectives of this review are to describe the specific advantages and disadvantages of the application of cytokine adsorption in the context of transplantation and examine, before and/or after organ transplantation, the benefits of the addition of a cytokine adsorption therapy protocol.

Efficacy of CytoSorb®: a systematic review and meta-analysis

INTRODUCTION

Cytokine adsorption using the CytoSorb® adsorber has been proposed in various clinical settings including sepsis, ARDS, hyperinflammatory syndromes, cardiac surgery or recovery after cardiac arrest. The aim of this analysis is to provide evidence for the efficacy of the CytoSorb® adsorber with regard to mortality in various settings.

METHODS

We searched PubMed, Cochrane Library database and the database provided by Cytosorbents™ (01.1.2010-29.5.2022). We considered randomized controlled trials and observational studies with control groups. The longest reported mortality was defined as the primary endpoint. We computed risk ratios and 95%-confidence intervals and used DerSimonian and Lairds random effects model. We analysed all studies combined and divided them into the subgroups: sepsis, cardiopulmonary bypass surgery (CPB), other severe illness, SARS-CoV-2 infection and recovery from cardiac arrest. The meta-analysis was registered in advance (PROSPERO: CRD42022290334).

RESULTS

Of an initial 1295 publications, 34 studies were found eligible, including 1297 patients treated with CytoSorb® and 1314 controls. Cytosorb® intervention did not lower mortality (RR [95%-CI]: all studies 1.07 [0.88; 1.31], sepsis 0.98 [0.74; 1.31], CPB surgery 0.91 [0.64; 1.29], severe illness 0.95 [0.59; 1.55], SARS-CoV-2 1.58 [0.50; 4.94]). In patients with cardiac arrest, we found a significant survival advantage of the untreated controls (1.22 [1.02; 1.46]). We did not find significant differences in ICU length of stay, lactate levels, or IL-6 levels after treatment. Of the eligible 34 studies only 12 were randomized controlled trials. All observational studies showed moderate to serious risk of bias.

INTERPRETATION

To date, there is no evidence for a positive effect of the CytoSorb® adsorber on mortality across a variety of diagnoses that justifies its widespread use in intensive care medicine.

CytoSorb in patients with coronavirus disease 2019: A rapid evidence review and meta-analysis

Background

After its approval by the European Union in 2011, CytoSorb therapy has been applied to control cytokine storm and lower the increased levels of cytokines and other inflammatory mediators in blood. However, the efficiency of this CytoSorb treatment in patients with coronavirus disease (COVID-19) still remains unclear. To elucidate the Cytosorb efficiency, we conducted a systematic review and single-arm proportion meta-analysis to combine all evidence available in the published literature to date, so that this comprehensive knowledge can guide clinical decision-making and future research.

Methods

The literature published within the period 1 December 2019 to 31 December 2021 and stored in the Cochrane Library, Embase, PubMed, and International Clinical Trials Registry Platform (ICTRP) was searched for all relevant studies including the cases where COVID-19 patients were treated with CytoSorb. We performed random-effects meta-analyses by R software (3.6.1) and used the Joanna Briggs Institute checklist to assess the risk of bias. Both categorical and continuous variables were presented with 95% confidence intervals (CIs) as pooled proportions for categorical variables and pooled means for continuous outcomes.

Results

We included 14 studies with 241 COVID-19 patients treated with CytoSorb hemadsorption. Our findings reveal that for COVID-19 patients receiving CytoSorb treatment, the combined in-hospital mortality was 42.1% (95% CI 29.5-54.6%, I² = 74%). The pooled incidence of adjunctive extracorporeal membrane oxygenation (ECMO) support was 73.2%. Both the C-reactive protein (CRP) and interleukin-6 (IL-6) levels decreased after CytoSorb treatment. The pooled mean of the CRP level decreased from 147.55 (95% CI 91.14-203.96) to 92.36 mg/L (95% CI 46.74-137.98), while that of IL-6 decreased from 339.49 (95% CI 164.35-514.63) to 168.83 pg/mL (95% CI 82.22-255.45).

Conclusions

The majority of the COVID-19 patients treated with CytoSorb received ECMO support. In-hospital mortality was 42.1% for the COVID-19 patients who had CytoSorb treatment. Both CRP and IL-6 levels decreased after Cytosorb treatment.

Use of CytoSorb© Hemoadsorption in Patients on Veno-Venous ECMO Support for Severe Acute Respiratory Distress Syndrome: A Systematic Review

Acute respiratory distress syndrome (ARDS) is associated with high morbidity and mortality. Adjunct hemoadsorption is increasingly utilized to target underlying hyperinflammation derived from ARDS. This article aims to review available data on the use of CytoSorb© therapy in combination with V-V ECMO in severe ARDS, and to assess the effects on inflammatory, laboratory and clinical parameters, as well as on patient outcomes. A systematic literature review was conducted and reported in compliance with principles derived from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. When applicable, a before-and-after analysis for relevant biomarkers and clinical parameters was carried out. CytoSorb© use was associated with significant reductions in circulating levels of C-reactive protein and interleukin-6 (p = 0.039 and p = 0.049, respectively). Increases in PaO2/FiO2 reached significance as well (p = 0.028), while norepinephrine dosage reductions showed a non-significant trend (p = 0.067). Mortality rates in CytoSorb© patients tended to be lower than those of control groups of most included studies, which, however, were characterized by high heterogeneity and low power. In an exploratory analysis on 90-day mortality in COVID-19 patients supported with V-V ECMO, the therapy was associated with a significantly reduced risk of death. Based on the reviewed data, CytoSorb© therapy is able to reduce inflammation and potentially improves survival in ARDS patients treated with V-V ECMO. Early initiation of CytoSorb© in conjunction with ECMO might offer a new approach to enhance lung rest and promote recovery in patients with severe ARDS.

Mortality and adverse events of hemoadsorption with CytoSorb® in critically ill patients: a systematic review and meta-analysis of randomized controlled trials

Background

The effects and safety of extracorporeal hemoadsorption with CytoSorb® in critically ill patients with inflammatory conditions are controversial.

Methods

We performed a systematic review with meta‐analysis and trial sequential analysis (TSA) of randomized‐controlled trials to assess the mortality and safety of CytoSorb® therapy in critically ill patients with inflammatory conditions. Electronic databases were searched up to April 2022. The primary outcome was mortality at longest follow‐up and secondary outcomes included various adverse event (AE) outcomes. Conflict of interest and funding of each trial were assessed. We calculated relative risk (RR) and 95% confidence interval (CI).

Results

Fourteen published (n = 764) and 4 unpublished (n = 111) trials were included. Eight trials were performed in medical ICU patients and 10 in complex cardiac surgery. Ten trials had significant industrial funding or an author conflict of interest. Hemoadsorption with CytoSorb® was associated with higher mortality at latest follow‐up (16 trials, n = 807, 120 of 402 [29.85%] patients in the CytoSorb® group vs. 98 of 405 [24.20%] patients in the control group, RR = 1.24 [95% CI, 1.04–1.49], p = .02, [TSA‐adjusted CI, 0.92–1.68]) and at 30‐days or in‐hospital (11 trials, n = 727; RR = 1.41 [95% CI, 1.06–1.88], p = .02, [TSA‐adjusted CI, 0.44–4.62]). Only one trial reported the definition of adverse event, while detailed results were reported in 3 trials; the risk of adverse events was not higher with CytoSorb®. Certainty of evidence ranged from low to very low.

Conclusion

Low certainty of evidence showed that the use of CytoSorb® might increase mortality in critically ill patients with inflammatory conditions. Adverse events were frequent but underreported and not systematically evaluated. Industrial funding and conflict of interest were common. Considerable uncertainty about the findings does not allow firm conclusions and suggests a need for high‐quality randomized trials to clarify mortality and adverse events related to CytoSorb®.

Editorial Comment

Hemoadsorption with CytoSorb® have been used in critically ill patients despite lack of high quality data from RCTs suggesting any patient‐important benefits. The findings from this systematic review and meta‐analysis suggests an increased risk of adverse events including mortality. With no apparent benefits and at the same time risk of harm, use of hemoadsorption with CytoSorb® in daily clinical practice cannot be recommended at this time.