Longitudinal Cytokine Profiling in Patients with Severe COVID-19 on Extracorporeal Membrane Oxygenation and Hemoadsorption

Albumin Infusion Reduces Fluid Loading for Postresuscitation Syndrome in a Pig Model of Refractory Cardiac Arrest Resuscitated With Venoarterial Extra Corporeal Membrane Oxygenation

Hemodynamic instability in postresuscitation syndrome worsens survival and neurological outcomes. Venoarterial extracorporeal membrane oxygenation (VA ECMO) for refractory cardiac arrest might improve outcomes. Hemodynamical support under VA ECMO relies on norepinephrine and crystalloids. The present work aims to assess the effects of albumin (ALB) infusion in a swine model of ischemic refractory cardiac arrest implanted by VA ECMO. Cardiac arrest was performed in 18 pigs and VA ECMO was initiated after 30 minutes cardiopulmonary resuscitation (CPR). Pigs were randomly assigned to standard care (norepinephrine + crystalloids) versus ALB group (ALB + standard care). Hemodynamical assessments were performed over 6 hours. Severe hypoalbuminemia was observed in the control group and could be reversed with ALB infusion. Total crystalloid load was significantly reduced with ALB infusion (1,000 [1,000-2,278] ml vs. 17,000 [10,000-19,000] ml, ALB versus control group, respectively, p < 0.001). There was no significant impact with regard to lactate clearance (29.16% [12.5-39.32] and 10.09% [6.78-29.36] for control versus ALB groups, respectively, p = 0.185), sublingual capillary microvascular parameters, or cerebral near-infrared spectrometer (NIRS) values. Compared to standard care, ALB infusion was highly effective in reducing fluid loading in a porcine model of postresuscitation syndrome after refractory cardiac arrest treated with VA ECMO.

Use of Therapeutic Apheresis methods in ICU

Apheresis is a modern medical approach in which plasma or cellular components are separated from the whole blood. Apheresis can be either diagnostic or therapeutic. Diagnostic apheresis is typically applied in hematology and cancer research. Therapeutic Apheresis (TA) includes a broad spectrum of extracorporeal treatments applied in various medical specialties, including Intensive Care Unit (ICU). Considering the complexity of the pathophysiologic characteristics of various clinical entities and in particular sepsis, apheresis methods are becoming increasingly applicable. Therapeutic Plasma Exchange (TPE) is the most common used method in ICU. It is considered as first line therapy for Thrombotic Thrombocytopenic Purpura (TTP) and Guillain Barre Syndrome, while the current data for sepsis are scarce. Over the last decades, technologic evolution has led to increasing application of new and more selective methods based on adsorptive techniques. In this review we will describe the current data of characteristics of different techniques, safety and clinical impact of apheresis methods used in ICUs.

Hemoadsorption in acute respiratory distress syndrome patients requiring venovenous extracorporeal membrane oxygenation: a systematic review

BACKGROUND

Venovenous extracorporeal membrane oxygenation (VV ECMO) has been widely used for severe acute respiratory distress syndrome (ARDS) in recent years. However, the role of hemoadsorption in ARDS patients requiring VV ECMO is unclear.

METHODS

Therefore, we conducted a systematic review to describe the effect of hemoadsorption on outcomes of ARDS patients requiring VV ECMO and elucidate the risk factors for adverse outcomes. We conducted and reported a systematic literature review based on the principles derived from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The systematic review searched Embase, CINHAL, and Pubmed databases for studies on ARDS patients receiving hemoadsorption and VV ECMO. The demographic data, clinical data and biological data of the patients were collected.

RESULTS

We ultimately included a total of 8 articles including 189 patients. We characterized the population both clinically and biologically. Our review showed most studies described reductions in inflammatory markers and fluid resuscitation drug dosage in ARDS patients with Coronavirus disease 2019 (COVID-19) or sepsis after hemoadsorption.

CONCLUSION

Because most of the studies have the characteristics of high heterogeneity, we could only draw very cautious conclusions that hemoadsorption therapy may enhance hemodynamic stability in ARDS patients with COVID-19 or sepsis receiving VV ECMO support. However, our results do not allow us to draw conclusions that hemoadsorption could reduce inflammation and mortality. Prospective randomized controlled studies with a larger sample size are needed in the future to verify the role of hemoadsorption in ARDS patients requiring VV ECMO.

EFFICACY OF SUPPLEMENTAL HEMOADSORPTION THERAPY ON SEVERE AND CRITICAL PATIENTS WITH COVID-19: AN EVIDENCE-BASED ANALYSIS

ABSTRACT

Background: The COVID-19 pandemic has posed a disproportionately high threat to the global health system and social stability. COVID-19 damage can lead to hyperinflammation and tissue damage due to a "cytokine storm," which in turn contributes to an increase in the mortality rate. Extracorporeal hemoadsorption therapy (HAT) in patients with severe COVID-19 may improve organ function and stabilize hemodynamic status; however, the effects of supplemental HAT remain controversial. Methods: The Cochrane Library, Embase, and PubMed databases were comprehensively searched from inception to August 20, 2022, for potential studies. Results: A total of 648 patients with severe COVID-19 in three randomized controlled trials and 11 observational studies met the inclusion criteria. A meta-analysis indicated that supplemental HAT significantly improved the mortality rate of patients with severe COVID-19 compared with conventional therapy (relative risk [RR] = 0.74, 95% confidence interval [CI] = 0.56 to 0.96, P = 0.026). In subgroup analyses, supplemental HAT significantly decreased mortality rates in patients without extracorporeal membrane oxygenation (ECMO) support (RR = 0.59, 95% CI = 0.44-0.79, P < 0.0001), while a significant difference was not observed in patients requiring ECMO support (RR = 1.61, 95% CI = 0.63-4.09, P = 0.316). Standardized mean difference (SMD) meta-analysis showed that IL-6 removal was more significant in HAT group than conventional therapy group (SMD = 0.46, 95% CI = 0.01 to 0.91, P = 0.043), followed by C-reactive protein (SMD = 0.70, 95% CI = -0.04 to 1.44, P = 0.065) and IL-8 (SMD = 0.36, 95% CI = -0.34 to 1.07, P = 0.311). No evidence of substantial publication bias concerning mortality was observed. Conclusion: Given the better mortality outcomes, HAT confers clinical benefits to patients with severe COVID-19, which correlated with cytokine removal by HAT. Cytokine adsorption may not provide clinical benefits for patients with severe COVID-19 requiring ECMO and should be used with caution. However, because of the very low quality of evidence, multicenter randomized trials with large sample sizes are required to verify these findings.

Extracorporeal hemoadsorption in critically ill COVID-19 patients on VV ECMO: the CytoSorb therapy in COVID-19 (CTC) registry

OBJECTIVES

The CytoSorb therapy in COVID-19 (CTC) registry evaluated the clinical performance and treatment parameters of extracorporeal hemoadsorption integrated with veno-venous extracorporeal membrane oxygenation (VV ECMO) in critically ill COVID-19 patients with acute respiratory distress syndrome (ARDS) and respiratory failure under US FDA Emergency Use Authorization.

DESIGN

Multicenter, observational, registry (NCT04391920).

SETTING

Intensive care units (ICUs) in five major US academic centers between April 2020 and January 2022.

PATIENTS

A total of 100 critically ill adults with COVID-19-related ARDS requiring VV ECMO support, who were treated with extracorporeal hemoadsorption.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Baseline demographics, clinical characteristics, laboratory values and outcomes were recorded following individual ethics committee approval at each center. Detailed data on organ support utilization parameters and hemoadsorption treatments were also collected. Biomarker data were collected according to the standard practice at each participating site, and available values were compared before and after hemoadsorption. The primary outcome of mortality was evaluated using a time-to-event analysis. A total of 100 patients (63% male; age 44 ± 11 years) were included. Survival rates were 86% at 30 days and 74% at 90 days. Median time from ICU admission to the initiation of hemoadsorption was 87 h and was used to define two post hoc groups: ≤ 87 h (group-early start, GE) and > 87 h (group-late start, GL). After the start of hemoadsorption, patients in the GE versus GL had significantly shorter median duration of mechanical ventilation (7 [2-26] vs. 17 [7-37] days, p = 0.02), ECMO support (13 [8-24] vs. 29 [14-38] days, p = 0.021) and ICU stay (17 [10-40] vs 36 [19-55] days, p = 0.002). Survival at 90 days in GE was 82% compared to 66% in GL (p = 0.14). No device-related adverse events were reported.

CONCLUSIONS

In critically ill patients with severe COVID-19-related ARDS treated with the combination of VV-ECMO and hemoadsorption, 90-day survival was 74% and earlier intervention was associated with shorter need for organ support and ICU stay. These results lend support to the concept of "enhanced lung rest" with the combined use of VV-ECMO plus hemoadsorption in patients with ARDS.

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.

Very Low Driving-Pressure Ventilation in Patients With COVID-19 Acute Respiratory Distress Syndrome on Extracorporeal Membrane Oxygenation: A Physiologic Study

OBJECTIVES

To determine in patients with acute respiratory distress syndrome (ARDS) on venovenous extracorporeal membrane oxygenation (VV ECMO) whether reducing driving pressure (ΔP) would decrease plasma biomarkers of inflammation and lung injury (interleukin-6 [IL-6], IL-8, and the soluble receptor for advanced glycation end-products sRAGE).

DESIGN

A single-center prospective physiologic study.

SETTING

At a single university medical center.

PARTICIPANTS

Adult patients with severe COVID-19 ARDS on VV ECMO.

INTERVENTIONS

Participants on VV ECMO had the following biomarkers measured: (1) pre-ECMO with low-tidal-volume ventilation (LTVV), (2) post-ECMO with LTVV, (3) during low-driving-pressure ventilation (LDPV), (4) after 2 hours of very low driving-pressure ventilation (V-LDPV, main intervention ΔP = 1 cmH2O), and (5) 2 hours after returning to LDPV.

MAIN MEASUREMENTS AND RESULTS

Twenty-six participants were enrolled; 21 underwent V-LDPV. There was no significant change in IL-6, IL-8, and sRAGE from LDPV to V-LDPV and from V-LDPV to LDPV. Only participants (9 of 21) with nonspontaneous breaths had significant change (p < 0.001) in their tidal volumes (Vt) (mean ± SD), 1.9 ± 0.5, 0.1 ± 0.2, and 2.0 ± 0.7 mL/kg predicted body weight (PBW). Participants with spontaneous breathing, Vt were unchanged-4.5 ± 3.1, 4.7 ± 3.1, and 5.6 ± 2.9 mL/kg PBW (p = 0.481 and p = 0.065, respectively). There was no relationship found when accounting for Vt changes and biomarkers.

CONCLUSIONS

Biomarkers did not significantly change with decreased ΔPs or Vt changes during the first 24 hours post-ECMO. Despite deep sedation, reductions in Vt during V-LDPV were not reliably achieved due to spontaneous breaths. Thus, patients on VV ECMO for ARDS may have higher Vt (ie, transpulmonary pressure) than desired despite low ΔPs or Vt.

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.

Apheresis and COVID-19 in intensive care unit (ICU)

Coronavirus disease 2019 (COVID-19) is a contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was identified in Wuhan, China, in December 2019. The disease has since spread worldwide, and on March 2020 the World Health Organization (WHO) declared it as pandemic, causing a public health crisis. Symptoms of COVID-19 are variable, ranging from mild symptoms like fever, cough, and fatigue to severe illness. Elderly patients and those with comorbidities like cardiovascular disease, diabetes, chronic respiratory disease, or cancer are more likely to develop severe forms of the disease. Asymptomatic infections have been well documented. Accumulating evidence suggests that the severity of COVID-19 is due to high levels of circulating inflammatory mediators including cytokines and chemokines leading to cytokine storm syndrome (CSS). Patients are admitted in ICU with severe respiratory failure, but can also develop acute renal failure and multi organ failure. Advances in science and technology have permitted the development of more sophisticated therapies such as extracorporeal organ support (ECOS) therapies that includes renal replacement therapies (RRTs), venoarterial (VA) or veno-venous (VV) extracorporeal membrane Oxygenation (ECMO), extracorporeal CO2 removal (ECCO2R), liver support systems, hemoperfusion, and various blood purification devices, for the treatment of ARDS and septic shock.

Hemoperfusion in the intensive care unit

Multiple organ failure following a septic event derives from immune dysregulation. Many of the mediators of this process are humoral factors (cytokines), which could theoretically be cleared by direct adsorption through a process called hemoperfusion. Hemoperfusion through devices, which bind specific molecules like endotoxin or theoretically provide non-specific adsorption of pro-inflammatory mediators has been attempted and studied for several decades with variable results. More recently, technological evolution has led to the increasing application of adsorption due to more biocompatible and possibly more efficient biomaterials. As a result, new indications are developing in this field, and novel tools are available for clinical use. This narrative review will describe current knowledge regarding technical concepts, safety, and clinical results of hemoperfusion. Finally, it will focus on the most recent literature regarding adsorption applied in critically ill patients and their indications, including recent randomized controlled trials and future areas of investigation. Clinical trials for the assessment of efficacy of hemoperfusion in septic patients should apply the explanatory approach. This includes a highly selected homogenous patient population. Enrichment criteria such as applying genetic signature and molecular biomarkers allows the identification of subphenotypes of patients. The intervention must be delivered by a multidisciplinary team of trained personnel. The aim is to maximize the signals for efficacy and safety. In a homogenous cohort, confounding uncontrolled variables are less likely to exist. Trials with highly selected populations have a high internal validity but poor generalizability. The parallel design described in the figure is robust and usually is required by regulatory agencies for the approval of a new treatment. Allocation concealment and randomization are key to minimize bias such as confirmation bias, observer bias. The intervention should be delivered following a strict protocol. Deviations from the protocol might negatively influence the potential effects of the therapies. Surrogates such as cytokine measurement are adequate primary outcomes in phase 3 trials with small sample size because there is a higher likelihood of finding positive results concerning surrogate markers than in respect with clinical outcomes. Once a trial shows positive results concerning surrogate markers, a rationale for another phase 3 trial exploring clinical outcomes is built, justifying the allocation of financial sources to the intended trial.

Effect of Hemadsorption Therapy in Critically Ill Patients with COVID-19 (CYTOCOV-19): A Prospective Randomized Controlled Pilot Trial

INTRODUCTION

Immunomodulatory therapies have shown beneficial effects in patients with severe COVID-19. Patients with hypercytokinemia might benefit from the removal of inflammatory mediators via hemadsorption.

METHODS

Single-center prospective randomized trial at the University Medical Center Hamburg-Eppendorf (Germany). Patients with confirmed COVID-19, refractory shock (norepinephrine ≥0.2 µg/kg/min to maintain a mean arterial pressure ≥65 mm Hg), interleukin-6 (IL-6) ≥500 ng/L, and an indication for renal replacement therapy or extracorporeal membrane oxygenation were included. Patients received either hemadsorption therapy (HT) or standard medical therapy (SMT). For HT, a CytoSorb® adsorber was used for up to 5 days and was replaced every 18-24 h. The primary endpoint was sustained hemodynamic improvement (norepinephrine ≤0.05 µg/kg/min ≥24 h).

RESULTS

Of 242 screened patients, 24 were randomized and assigned to either HT (N = 12) or SMT (N = 12). Both groups had similar severity as assessed by SAPS II (median 75 points HT group vs. 79 SMT group, p = 0.590) and SOFA (17 vs. 16, p = 0.551). Median IL-6 levels were 2,269 (IQR 948-3,679) and 3,747 (1,301-5,415) ng/L in the HT and SMT groups at baseline, respectively (p = 0.378). Shock resolution (primary endpoint) was reached in 33% (4/12) versus 17% (2/12) in the HT and SMT groups, respectively (p = 0.640). Twenty-eight-day mortality was 58% (7/12) in the HT compared to 67% (8/12) in the SMT group (p = 1.0). During the treatment period of 5 days, 6/12 (50%) of the SMT patients died, in contrast to 1/12 (8%) in the HT group.

CONCLUSION

HT was associated with a non-significant trend toward clinical improvement within the intervention period. In selected patients, HT might be an option for stabilization before transfer and further therapeutic decisions. This finding warrants further investigation in larger trials.

Blood purification therapy in patients with severe COVID-19 requiring veno-venous ECMO therapy: A retrospective study

OBJECTIVE

Patients with severe manifestations of COVID-19 might exhibit characteristics of a sepsis-like syndrome that can progress to multiple organ failure and ultimately death. Underlying mechanism have been explored and suggest a profound dysregulation of the immune system associated with hyperinflammation, hemodynamic instability and respiratory failure. Besides standard intensive care treatment, approaches modulating the dysregulated immune response, such as CytoSorb hemoadsorption, have been used. However, data of ECMO-dependent patients in comparison to a control cohort remain scarce.

METHODS

Included were 26 critically ill COVID-19 patients requiring high-flow veno-venous extracorporeal membrane oxygenation (high-flow VV ECMO) therapy due to severe acute respiratory distress syndrome (ARDS), of whom 16 were additionally treated with an extracorporeal hemoadsorption device, and compared to a control group of 10 patients. Assessed were levels of inflammatory markers, vasopressor requirements, oxygenation parameters, as well as clinically relevant outcome variables. Data were prospectively recorded and retrospectively analyzed.

RESULTS

Treatment with the applied multimodal therapy approach resulted in a stabilization in hemodynamics, a control of the hyperinflammatory response as evidenced by a significant reduction in inflammatory mediators, as well as a marked improvement in lung function. No device related adverse events were observed while treatment appeared safe and feasible.

CONCLUSION

Treatment of a critically ill COVID-19 ARDS patients with combined VV ECMO support and hemoadsorption therapy led to a rapid and sustained hemodynamic stabilization, a control of the uncontrolled inflammatory response and an improvement in oxygenation. Given these signals pointing toward a patient-oriented benefit of extracorporeal hemoadsorption therapy in those patients, future controlled, randomized studies should focus on the investigation of the appropriate timing and dosing of this promising treatment modality.

Extracorporeal Cytokine Removal in Critically Ill COVID-19 Patients: A Case Series

Introduction: Extracorporeal hemoadsorption (HA) is a potential adjunctive therapy in severe cases of COVID-19 associated pneumonia. In this retrospective study we report data from critically ill patients treated with HA during the first and second wave of the pandemic. Patients and Methods: All patients, who received HA therapy with CytoSorb within the first 96 h of intensive care unit (ICU) admission without hospital-acquired bacterial superinfection, were included. Clinical and laboratory data were collected: on admission, before (T_B) and after (T_A) HA therapy. Results: Out of the 367 COVID-19 cases, 13 patients were treated with CytoSorb, also requiring mechanical ventilation and renal replacement therapy. All patients were alive at the end of HA, but only 3 survived hospital stay. From T_B-T_A there was a tendency of decreasing norepinephrine requirement: 193.7 [IQR: 34.8-270.4] to 50.2 [6.5-243.5] ug/kg/day and increasing PaO2/FiO2 ratio 127.8 (95% CI: 96.0-159.6) to 155.0 (115.3-194.6) mmHg but they did not reach statistical significance (p = 0.14 and 0.58, respectively). Treatment related adverse events were not reported. Conclusion: The treatment was well-tolerated, and there was a tendency toward an improvement in vasopressor need and oxygenation during the course of HA. These observations render the need for prospective randomized trials.

Evaluation of cytokine response to extracorporeal membrane oxygenation

RATIONALE

Increased cytokine response is common in patients receiving extracorporeal life support and is often a poor prognostic indicator. There is interest in using adjunctive cytokine adsorption technologies to reduce inflammatory burden, However, it is debated whether extracorporeal membrane oxygenation (ECMO) itself provides therapeutic benefit beyond gas exchange. Thus, we sought to characterize the inflammatory profile of ECMO in the first 72-96 h of and quantify its effect on cytokine levels in a case series of patients undergoing ECMO.

METHODS

Eight patients initiating ECMO were studied. Of these, we measured cytokines pre- and post-oxygenator over 96 h. Comparisons of cytokine levels were made across the oxygenator and over time.

RESULTS

The average age of patients was 64.3 years with 62% being male. Centrally cannulated patients had higher IL-6 levels (820.43 vs. 6907.53 pg/ml, p < 0.03), whereas peripherally cannulated patients had higher IL-12p70 levels (7.73 vs. 2.59 pg/ml, p < 0.05). Cytokine levels on day one included IL-12p70 (4.17 ± 2.56), IL-6 (4971.23 ± 8569.88), TNF (undetected), IL-8 (346.68 ± 670.18), IL-1B (undetected), and IL-10 (72.27 ± 87.9). Cytokine levels increased over 96 h; however, no significant differences were appreciated despite blood product transfusion. On day 3, IL-12p70 levels were significantly lower post-oxygenator (p < 0.05).

CONCLUSION

The inflammatory profile of ECMO does not change significantly over the early course of illness when accounting for transfusion. However, the decrease in IL-12p70 specifically at day 3 of ECMO may indicate adsorption of specific inflammatory markers by the oxygenator although the clinical significance of this is still unknown. Further investigation of the oxygenator on cytokine response is warranted.

The Use of CytoSorb Therapy in Critically Ill COVID-19 Patients: Review of the Rationale and Current Clinical Experiences

The COVID-19 pandemic has led to the biggest global health crisis of our lifetime. There is accumulating evidence that a substantial number of critically ill COVID-19 patients exhibit a dysregulated host response manifesting as cytokine storm or cytokine release syndrome, which in turn contributes to the high observed rates of mortality. Just as in other hyperinflammatory conditions, extracorporeal cytokine removal may have potential beneficial effects in this subgroup of COVID-19 patients. The CytoSorb blood purification device is the most extensively investigated cytokine removal platform with considerable evidence suggesting that early intervention can provide rapid hemodynamic stabilization and improvement in vital organ functions. The purpose of this review is to provide an overview of the pathophysiological background of hyperinflammation in COVID-19 and to summarize the currently available evidence on the effects of hemoadsorption in these patients.

Opportunities, controversies, and challenges of extracorporeal hemoadsorption with CytoSorb during ECMO

Extracorporeal membrane oxygenation (ECMO) is frequently used in many centers around the globe for various indications. However, prognosis is often poor even with all supportive therapies, and in many cases, clinical deterioration is associated with inflammation. Hemoadsorption with CytoSorb is a novel approach to limit the inflammatory response, and the device can be safely and easily installed into ECMO circuits. CytoSorb has been used more than 130.000 times to date, but because randomized controlled trials are largely lacking, there is substantial debate on its use. Here, experts from critical care medicine, cardiology, cardiac surgery, and perfusion technology discuss the pros and cons of this novel therapy and outline the future aspects for its clinical application and research.

Cytokine adsorption in patients with severe COVID-19 pneumonia requiring extracorporeal membrane oxygenation (CYCOV): a single centre, open-label, randomised, controlled trial

Background

We sought to clarify the benefit of cytokine adsorption in patients with COVID-19 supported with venovenous extracorporeal membrane oxygenation (ECMO).

Methods

We did a single-centre, open-label, randomised, controlled trial to investigate cytokine adsorption in adult patients with severe COVID-19 pneumonia requiring ECMO. Patients with COVID-19 selected for ECMO at the Freiburg University Medical Center (Freiburg, Germany) were randomly assigned (1:1) to receive cytokine adsorption using the CytoSorb device or not. Randomisation was computer-generated, allocation was concealed by opaque, sequentially numbered sealed envelopes. The CytoSorb device was incorporated into the ECMO circuit before connection to the patient circuit, replaced every 24 h, and removed after 72 h. The primary endpoint was serum interleukin-6 (IL-6) concentration 72 h after initiation of ECMO analysed by intention to treat. Secondary endpoints included 30-day survival. The trial is registered with ClinicalTrials.gov (NCT04324528) and the German Clinical Trials Register (DRKS00021300) and is closed.

Findings

From March 29, 2020, to Dec 29, 2020, of 34 patients assessed for eligibility, 17 (50%) were treated with cytokine adsorption and 17 (50%) without. Median IL-6 decreased from 357·0 pg/mL to 98·6 pg/mL in patients randomly assigned to cytokine adsorption and from 289·0 pg/mL to 112·0 pg/mL in the control group after 72 h. One patient in each group died before 72 h. Adjusted mean log IL-6 concentrations after 72 h were 0·30 higher in the cytokine adsorption group (95% CI −0·70 to 1·30, p=0·54). Survival after 30 days was three (18%) of 17 with cytokine adsorption and 13 (76%) of 17 without cytokine adsorption (p=0·0016).

Interpretation

Early initiation of cytokine adsorption in patients with severe COVID-19 and venovenous ECMO did not reduce serum IL-6 and had a negative effect on survival. Cytokine adsorption should not be used during the first days of ECMO support in COVID-19.

Funding

None.