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

Effect of a biomimetic pathogen adsorbing device on inflammatory biomarkers in COVID-19 patients

INTRODUCTION

The Seraph 100 Microbind Affinity blood filter eliminate bacteria, viruses, fungi and toxins from blood stream.

METHODS

This is a prospective multicenter observational biomarker trial in PCR-positive SARS-CoV-2 patients with acute respiratory failure. Biomarkers were sequentially tested at three time points.

RESULTS

Forty-two patients with SARS-CoV-2 detected by PCR with acute respiratory failure were included. When receiving hemoperfusion treatment, 27 (64%) patients were on mechanical ventilation, 41 (98%) patients were treated in the ICU. The 3-month survival was 52%. After one hemoperfusion treatment cycle, D-dimer (p = 0.014), hemoglobin (p = 0.003) and LDH (p = 0.001) concentrations were significantly reduced 4 days after treatment. From the multiplex assay IL-1b, CXCL8/ IL-8, IL-10, IL-13, IL-15, CCL11/Eotaxin, G-CSF, and CXCL10/IP-10 were significantly reduced 1 h after treatment, however not 4 days later.

CONCLUSION

Hemoperfusion with Seraph 100 Microbind Affinity Filter in patients with severe COVID-19 can transiently reduce several inflammatory biomarkers in the blood.

Use of Extracorporeal Membrane Oxygenation for Patients with Coronavirus Disease 2019 Infection

The coronavirus disease 2019 (COVID-19) pandemic was a cataclysmic event that infected over 772 million and killed over 6.9 million people worldwide. The pandemic pushed hospitals and society to their limits and resulted in incredibly severe respiratory disease in millions of people. This severe respiratory disease often necessitated maximum medical therapy, including the use of extracorporeal membrane oxygenation. While our understanding of COVID-19 and its treatment continue to evolve, we review the current evidence to guide the care of patients with severe COVID-19 infection.

Extracorporeal Elimination of Pro- and Anti-inflammatory Modulators by the Cytokine Adsorber CytoSorb® in Patients with Hyperinflammation: A Prospective Study

INTRODUCTION

The release of pro-inflammatory cytokines in critically ill patients with sepsis leads to endothelial dysfunction resulting in cardiocirculatory insufficiency. Their extracorporeal elimination using the cytokine adsorber CytoSorb® (CS) (adsorption of especially hydrophobic molecules < 60 kDa) might be promising, but data about the adsorption capacity as well as a potential harmful adsorption of anti-inflammatory cytokines are missing so far.

METHODS

The prospective Cyto-SOLVE-study included 15 patients with sepsis or other hyperinflammatory conditions (interleukin 6 > 500 pg/ml), continuous kidney replacement therapy, and the application of CS. Various cytokines and chemokines were measured pre- and post-CS as well as in patients' blood at predefined timepoints. Significant changes in the concentrations were detected with the Wilcoxon test with associated samples. Clearance of the adsorber (ml/min) was calculated with: b l o o d f l o w ∗ c o n c e n t r a t i o n p r e - p o s t c o n c e n t r a t i o n pre . RESULTS: Most of the inflammatory mediators showed a high initial extracorporeal clearance of 70-100 ml/min after CS installation, which dropped quickly to 10-30 ml/min after 6 h of treatment. No difference in clearance was observed between pro- and anti-inflammatory cytokines. Despite extracorporeal adsorption, a significant (p < 0.05) decrease in the blood concentration after 6 h was only observed for the pro-inflammatory cytokines tumor necrosis factorα (TNF-α) (median 284 vs. 230 pg/ml), vascular endothelial growth factor (VEGF) (median 294 vs. 252 pg/ml), macrophage inflammatory protein 1a (MIP-1a) (median 11.1 vs. 9.0 pg/ml), and regulated upon activation, normal T cell expressed and secreted (RANTES) (median 811 vs. 487 pg/ml) as well as the anti-inflammatory cytokines interleukin 4 (median 9.3 vs. 6.4 pg/ml), interleukin 10 (median 88 vs. 56 pg/ml), and platelet-derived growth factor (PDGF) (median 177 vs. 104 pg/ml). A significant (p < 0.05) decrease in patients' blood after 12 h was only detected for interleukin 10.

CONCLUSIONS

CS can adsorb pro- as well as anti-inflammatory mediators with no relevant difference regarding the adsorption rate. A fast saturation of the adsorber resulted in a rapid decrease of the clearance. The potential clinical benefit or harm of this unspecific cytokine adsorption needs to be evaluated in the future.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04913298, registration date June 4, 2021.

Simultaneous removal of endotoxins, inflammatory mediators and uremic toxins in ICU patients with septic shock: a retrospective cohort study

Sepsis, one of the leading causes of death, is still lacking specific treatment. OXIRIS (BAXTER, Deerfield, IL, USA) is the first device allowing combined removal of endotoxins, inflammatory mediators and uremic toxins, alongside fluid balance control. Available data is very limited. This retrospective propensity score-matched cohort study of adult patients with septic shock aimed to evaluate septic shock duration and mortality in patients treated with either standard of care renal replacement therapy (RRT) or RRT with combined hemoadsorption, who were admitted to the interdisciplinary surgical intensive care unit at Heidelberg University Hospital during the years 2018 through 2021. Main outcomes were duration of shock, thirty-day mortality and plasma interleukin-6 levels before and after initiation of hemoadsorption. Included were 117 patients (female, 33%; male 67%); median age: 67 (16) years. After matching: 42 patients (female, 33%; male, 67%); mean age: 59.1 ± 13.8 years. There was no statistically significant difference in septic shock duration (p = 0.94; hazard ratio (HR) 0.97 (95% CI, 0.48-1.97)). Thirty-day survival analysis showed a non-statistically significant survival difference. (p = 0.063; HR 0.43 (95% CI, 0.17-1.09)). A post-hoc 90-day survival analysis revealed statistically significant longer survival and lower death hazard ratio in patients treated with RRT + HA (p = 0.037; HR = 0.42 (95% CI, 0.18-0.99). In conclusion, RRT with combined hemoadsorption of endotoxins, inflammatory mediators and uremic toxins is a modality worth further investigation.

The Role of Early Hemoadsorption in Severe COVID-19 Treatment: A Pilot Randomized Controlled Trial

INTRODUCTION

Hemoadsorption, an extracorporeal apheresis technique, is reportedly used in severe COVID-19 patients. However, limited evidence from randomized clinical trials supports this practice.

METHODS

In this single-center study, severe COVID-19 patients requiring ICU admission were randomly assigned (1:1) to receive HA-330 hemoadsorption in combination with standard treatment or standard therapy alone. Both groups received tocilizumab intravenously if their clinical conditions worsened within 24-48 h. The primary outcome was mortality from any cause within 28 days after randomization. Secondary outcomes included mechanical ventilator-free days, daily C-reactive protein levels, oxygenation (defined by PaO2/FiO2 ratio), daily sequential organ failure assessment score, and severity score of lung infiltration on chest X-rays (CXR RALE score).

RESULTS

A total of 28 patients underwent randomization, with 14 (50%) receiving HA-330 hemoadsorption. Only 9 out of 14 patients (64.3%) in the control group experienced clinical worsening and were subsequently administered intravenous tocilizumab. At 28 days, the mortality rate was significantly lower in the intervention group (28.57% vs. 78.57%, p = 0.021), with a hazard ratio of death of 0.26 (95% CI = 0.08-0.81; p = 0.021). All of secondary outcomes were comparable in both groups.

CONCLUSION

Based on our pilot randomized trial, the early application of HA-330 hemoadsorption in patients with severe COVID-19 may establish a favorable outcome in term of mortality. These data provide the initial proof of concept for conducting a large-scale study in the future.

Phenotyping Refractory Cardiogenic Shock Patients Receiving Venous-Arterial Extracorporeal Membrane Oxygenation Using Machine Learning Algorithms

Background

This study used machine learning to categorize cardiogenic shock (CS) patients treated with venous-arterial extracorporeal membrane oxygenation (VA-ECMO) into distinct phenotypes. Subsequently, it aimed to clarify the wide mortality variance observed in refractory CS, attributing it to the condition's inherent heterogeneity.

Methods

This study enrolled a cohort of CS patients who received VA-ECMO support. By employing rigorous machine learning (ML) techniques, we generated and validated clusters based on determinants identified through algorithmic analysis. These clusters, characterized by distinct clinical outcomes, facilitated the examination of clinical and laboratory profiles to enhance the understanding of patient responses to VA-ECMO treatment.

Results

In a study of 210 CS patients undergoing VA-ECMO treatment, 70.5% were male with a median age of 62, ranging from 53 to 67 years. Survival rates were 67.6% during VA-ECMO and 49.5% post-discharge. Patients were classified into three phenotypes based on the clinical and laboratory findings: "platelet preserved (I)", those with stable platelet counts, "hyperinflammatory (II)", those indicating significant inflammation, and "hepatic-renal (III)", those showing compromised liver and kidney functions. Mortality rates (25.0%, 52.8%, and 55.9% for phenotypes I, Ⅱ, and Ⅲ, respectively (p = 0.005)) varied significantly among these groups, highlighting the importance of phenotype identification in patient management.

Conclusions

This study identified three distinct phenotypes among refractory CS patients treated using VA-ECMO, each with unique clinical characteristics and mortality risks. Thus, highlighting the importance of early detection and targeted intervention, these findings suggest that proactive management could improve outcomes for those showing critical signs.

Efficacy of additional hemoperfusion in hospitalized patients with severe to critical COVID-19 disease

The evidence supporting additional hemoperfusion (HP) with cytokine adsorbents for improving clinical outcomes in severe to critical coronavirus disease 2019 (COVID-19) patients remains limited. We compared severe to critical COVID-19 patients who received additional HP with a cytokine adsorbent to matched cases receiving standard medical treatment (SMT). The primary outcome was hospital mortality. In our study, we matched 45 patients who received additional HP 1:1 with the SMT group based on key clinical parameters. The hospital mortality rates did not differ between the groups (33% vs 38%, p = 0.83). The HP group had a significantly shorter ICU stay (22 vs 32 days; p = 0.017) and reduced mechanical ventilation duration (15 vs 35 days; p < 0.001). Additionally, the incidence of pulmonary complications (20% vs 42%; p = 0.04), sepsis (38% vs 64%; p = 0.02), and disseminated intravascular coagulopathy (DIC) (13% vs 33%; p = 0.046) were significantly lower in the HP group. In conclusion, among severe to critical COVID-19 patients, additional HP with a cytokine adsorbent did not improve hospital mortality. However, it reduced ICU length of stay, mechanical ventilator days, and incidences of lung complications, sepsis, and DIC. Trial registration: TCTR20231002006. Registered 02 October 2023 (retrospectively registered).

Treatment of acute kidney injury with continuous renal replacement therapy and cytokine adsorber (CytoSorb®) in critically ill patients with COVID-19

INTRODUCTION

This retrospective study aimed to evaluate the 30 and 60-day survival of critically ill patients with COVID-19 and AKI.

METHODS

Inflammatory and biochemical biomarkers, length of intensive care unit (ICU) stay and mortality at Day 30 and Day 60 after ICU admission were analyzed. A total of 44 patients treated with continuous renal replacement therapy (CRRT) with cytokine adsorber (CA group) were compared to 58 patients treated with CRRT alone (non-CA group).

RESULTS

Patients in CA group were younger, had better preserved kidney function prior to the beginning of CRRT and had higher levels of interleukin-6. There were no statistically significant differences in their comorbidities and in other measured biomarkers between the two groups. The number of patients who died 60 days after ICU admission was statistically significantly higher in non-CA group (p = 0.029).

CONCLUSION

Treatment with CRRT and cytokine adsorber may have positively influenced 60-day survival in our COVID-19 ICU patients with AKI.

Care Bundles to Improve Hemoperfusion Performance in Patients with Severe COVID-19: A Retrospective Study

Background/Objectives: Hemoperfusion (HP) is employed to modulate cytokine storms in severe coronavirus disease 2019 (COVID-19) patients, requiring careful attention for success and safety. Therefore, we investigated whether our care bundles could enhance HP performance. Methods: We conducted a retrospective cohort study on adult patients (≥20 years old) with severe COVID-19 pneumonia. In the first wave (Phase I), we identified HP-related issues and addressed them with care bundles in the second wave (Phase II). The care bundles included early temperature control, precise hemodynamic monitoring, and clot prevention measures for the HP membrane. The HP success rate and associated adverse events (AEs) were assessed between the two phases. Results: The study included 60 HP (HA330) sessions from 27 cases (Phase I: 21 sessions from 9 cases; Phase II: 39 sessions from 18 cases). Patient characteristics and treatments for COVID-19 were similar, except for baseline body temperature (BT) and heart rate (HR). Phase II showed a higher success rate (67% vs. 89%, p = 0.19), although it did not reach statistical significance. Phase I recorded a significantly higher frequency of AEs (3 [IQR 1, 4] events/case vs. 1 [IQR 0, 2] events/case, p = 0.014). After implementing the care bundles, hypothermia significantly decreased (78% vs. 33%, p = 0.037), with an adjusted odds ratio of 0.15; 95% CI 0.02-0.95, p = 0.044 for baseline BT. Conclusions: Further exploration with a larger sample size is required to establish the advantages of care bundles. However, the bundles' implementation has significantly improved hypothermia prevention.

The Effect of Cytokine Adsorption on Leukocyte and Platelet Activation after Extracorporeal Cardiopulmonary Resuscitation

BACKGROUND

 Post-cardiac arrest syndrome (PCAS) is a frequent complication following successful cardiopulmonary resuscitation and correlates with poor outcome. PCAS is characterized by an excessive inflammatory response to whole-body ischemia and reperfusion. Cytokine adsorption was suggested as an adjunctive treatment option for the removal of cytokines from the patients' blood to restore the physiological equilibrium of pro- and anti-inflammatory activity and thus mitigate hemodynamic instability and end-organ complications.

MATERIAL AND METHODS

 To better understand the cellular effects of cytokine adsorption in patients receiving extracorporeal cardiopulmonary resuscitation (ECPR) after in- and out-of-hospital cardiac arrest, we compared the activation status of neutrophils, monocytes, and platelets as well as the formation of platelet-leukocyte complexes in intravenous whole blood samples from an exploratory subgroup (n = 24) from the randomized CYTER study.

RESULT

 At 48 hours after initiation of ECPR, flow cytometry analyses did neither reveal significant differences in neutrophil (CD11b, CD66b, L-selectin, and PSGL-1) and monocyte (CD11b, L-selectin, and PSGL-1) surface molecule expression nor in circulating platelet-monocyte complexes between patients receiving cytokine adsorption and those without.

CONCLUSION

 Data did not show a relevant effect of cytokine adsorption on neutrophil and monocyte activation during the first 48 hours after initiation of ECPR.

Preliminary Experience of Extracorporeal Cytokine Hemoadsorption during Left Ventricular Assist Device Implantation in Cardiogenic Shock Patients

BACKGROUND

 Systemic inflammation due to cardiogenic shock is associated with vasoplegia leading to organ hypoperfusion, right heart failure, and poor clinical outcome. Extracorporeal cytokine hemoadsorption emerged to attenuate excessive levels of inflammatory cytokines, potentially improving patient outcomes. Nevertheless, its prognostic impact during high-risk left ventricular assist device (LVAD) implantation remains unknown.

METHODS

 In total, 40 consecutive patients with advanced heart failure underwent continuous-flow LVAD implantation at our institution between 2018 and 2020. Out of 25 high-risk patients in cardiogenic shock (Interagency Registry for Mechanically Assisted Circulatory Support profile 1 and 2), 9 patients (CytoSorb group) underwent LVAD implantation with and 16 patients (control group) without simultaneous cytokine hemoadsorption during cardiopulmonary bypass. Besides preoperative patient characteristics, postoperative lactate clearance, vasopressor administration and mean arterial pressure, perioperative complication, and 30-day mortality rates were retrospectively analyzed.

RESULTS

 Apart from an increased rate of reoperations within the CytoSorb group, baseline characteristics including the severity of ventricular dysfunction and consecutive signs of end-organ failure were similar in both groups. Preoperative short-term mechanical circulatory support bridging was comparable (66.7 vs. 75%; p = 0.66) prior to LVAD implantation. Procedural characteristics including intraoperative volume management and postoperative vasopressor administration were similar in both groups. There was no difference regarding postoperative lactate clearance, although postoperative mean arterial pressure was significantly higher in the control group (71.3 vs. 57.4 mm Hg; p < 0.01). Furthermore, the 30-day mortality rate was significantly higher in the CytoSorb group (33.3 vs. 0.0%; p = 0.01).

CONCLUSION

 Extracorporeal cytokine hemoadsorption during high-risk LVAD implantation was not associated with a decrease of postoperative vasopressor support, improved hemodynamics, or an accelerated lactate clearance.

Apheresis practice variation during the COVID-19 pandemic: Results of a survey

BACKGROUND

The COVID-19 pandemic affected healthcare delivery across all specialties including apheresis. To describe the changes in apheresis service practices that occurred during the pandemic, the American Society for Apheresis (ASFA) Apheresis Medicine Attending Physician Subcommittee conducted a survey study.

STUDY DESIGN AND METHODS

A 32-question survey was designed and distributed to 400 ASFA physician members on September 7, 2022. Attending physicians responded to questions about whether and how apheresis service practices changed during the COVID-19 pandemic compared with the time period prior to the pandemic in terms of: (1) procedure types and volumes, (2) patient consultation workflow, and (3) the use of telemedicine. Descriptive analyses were reported as number and frequency of responses.

RESULTS

The survey response rate was 13.8% (55/400). Of these respondents, 96.4% (53/55) were attending physicians. The majority of respondents (42/53, 79.2%) indicated that the types of procedures performed during COVID-19 compared to pre-pandemic did not change. Most frequently for apheresis procedure volume, respondents reported: no change in their monthly inpatient volume (21/47, 44.7%) and a decrease in their monthly outpatient volume (28/46, 60.9%). Prior to COVID-19, 75.0% (30/40) of respondents performed consultations at bedside for inpatients and 67.4% (29/43) performed consultations at bedside for outpatients. Bedside consultations decreased in both settings during the pandemic but were still most frequently performed by attending physicians. At the same time, the use of telemedicine increased for 15.4% of survey respondents during COVID-19.

CONCLUSION

Some, but not all, respondents observed or made changes to their apheresis service during the COVID-19 pandemic. A subset of changes, such as increased utilization of telemedicine, may persist.

Blood perfusion with polymyxin B immobilized columns in patients with COVID-19 requiring oxygen therapy

Extracorporeal blood purification with polymyxin B immobilized fiber column direct hemoperfusion (PMX-DHP), is reported to be effective in treating COVID-19 pneumonitis with oxygen demand. This multicenter prospective study evaluated the efficacy and safety of PMX-DHP in oxygen-requiring patients with COVID-19 admitted between September 28, 2020, and March 31, 2022. The primary endpoint was the percentage of clinical improvement 15 days after treatment. The secondary endpoint was the percentage of worsened disease status. Data from the COVID-19 patient registry were used for the synthetic control group. The improvement rate on Day 15 did not differ between PMX-treated patients and controls; however, the deterioration rate was 0.38 times lower in the PMX-treated group, and the death rates on Day 29 were 0 and 11.1% in the PMX-treated and control groups, respectively. The PMX group showed a 0.73 times higher likelihood for reduced intensive care demand, as 16.7% of PMX-treated patients and 22.8% of controls worsened. After treatment blood oxygenation improved, urinary β2-microglobulin and liver-type fatty acid-binding protein showed significant decreases, and IL-6 decreased once during treatment but did not persist. In this study, PMX treatment effectively prevented the worsening of COVID-19 pathology, accompanied by improved oxygenation. PMX treatment to remove activated cells may effectively improve patient outcomes.

Cytokine adsorption in patients with acute-on-chronic liver failure (CYTOHEP)-A single center, open-label, three-arm, randomized, controlled intervention pilot trial

BACKGROUND

To investigate the efficacy of bilirubin reduction by hemoadsorption with CytoSorb® in patients with acute-on-chronic liver failure (ACLF) receiving continuous renal replacement therapy (CRRT).

METHODS

A prospective, randomized, single-center, open-label, controlled pilot trial. Patients with ACLF, acute kidney injury, and serum bilirubin ≥5 mg/dL were assigned 1:1:1 to one of three study groups (CRRT with or without hemoadsorption, no CRRT). In the hemoadsorption group, the CytoSorb adsorber was incorporated into the CRRT system, replaced after 12, 24, and 48 h, and removed after 72 h. The primary endpoint was the serum bilirubin level after 72 h.

RESULTS

CYTOHEP was terminated early due to difficulties in recruiting patients and ethical concerns. Three of 9 patients (33%) were treated in each group. Comparing the three groups, mean bilirubin levels after 72 h were lower by -8.0 mg/dL in the "CRRT with hemoadsorption" group compared to "CRRT without hemoadsorption" (95% CI, -21.3 to 5.3 mg/dL; p = 0.17). The corresponding mean difference between "CRRT without hemoadsorption" and "no CRRT" was -1.4 mg/dL (95% CI, -14.2 to 11.5 mg/dL; p = 0.78). Comparing "CRRT with hemoadsorption" and "no CRRT," it was -9.4 mg/dL (95% CI, -20.8 to 2.1 mg/dL; p = 0.0854). Only 1/9 patients (11%, "no CRRT" group) survived day 30 after study inclusion but died on day 89. IL-6, liver function parameters, and clinical scores were similar between the study groups.

CONCLUSIONS

CYTOHEP failed to demonstrate that extracorporeal hemoadsorption combined with CRRT can reduce serum bilirubin in ACLF patients with acute kidney failure.

Ineffectiveness of hemoadsorption in large animals with abdominal sepsis: a randomized controlled porcine study

OBJECTIVES

The use of hemoadsorption (HA) has become popular in the treatment of vasoplegic states associated with massive cytokine release, including septic shock. However, this approach does not seem to be based on robust evidence, and it does not follow international guidelines. To understand the pathophysiological rationale and timing of HA, we conducted a large animal septic shock experiment.

DESIGN

Prospective randomized large-animal peritoneal septic shock experiment.

SETTING

Laboratory investigation.

SUBJECTS

Twenty-six anesthetized, mechanically ventilated, and instrumented pigs randomly assigned into (1) sham-operated group with HA (SHAM, n = 5); (2) sepsis animals without HA (SEPSIS, n = 5); (3) sepsis group with HA at norepinephrine initiation (EARLY, n = 8); and (4) sepsis group with HA initiated at norepinephrine rate reaching 0.5 μg/kg/min (LATE, n = 8).

INTERVENTIONS

Peritoneal sepsis was induced by cultivated autologous feces inoculation. A CytoSorb cartridge (200 g) with a blood flow rate of 200 mL/min and heparin anticoagulation was used to perform HA. The animals received sedation and intensive organ support up to 48 h or until they experienced cardiovascular collapse.

MEASUREMENTS AND MAIN RESULTS

Systemic hemodynamics, multiple-organ functions, and immune-inflammatory response were measured at predefined periods. The HA treatment was not associated with any measurable benefit in terms of systemic hemodynamics and organ support. The systemic inflammatory markers were unaffected by any of the treatment timings. In contrast, the HA resulted in higher vasopressor load and decreased 36-h survival (5 animals in SHAM (100%), 4 (80%) in SEPSIS, 4 (57%) in EARLY, and 2 (25%) in LATE; p = 0.041). The HA exposure in healthy animals was associated with hemodynamic deterioration, systemic inflammatory response, and cytopenia.

CONCLUSIONS

In this large-animal-controlled fulminant sepsis study, the HA was unable to counteract the disease progression in the early or advanced septic shock phase. However, findings from the HA-exposed sham animals suggest potential safety concerns.

The addition of Cytosorb in patients on VA-ECMO improves urinary output and ICU survival

INTRODUCTION

The aim of this study was to analyze the efficiency of CytoSorb adsorber in patients presenting with cardiogenic shock and treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO).

METHODS

Sixteen patients put on VA ECMO due to cardiogenic shock were included, stratified according to the use of Cytosorb adsorber in the first 24 h and compared across different clinical outcomes.

RESULTS

Significantly lower vasopressor doses were required among patients treated with Cytosorb at the initiation and before weaning from ECMO. Furthermore, these patients showed significantly higher urine output before weaning and lower lactate levels during the extracorporeal support. Finally, the mortality rate was lower among the Cytosorb therapy group (22.2% vs 57.1%).

CONCLUSION

While a decrease in vasopressor doses was already associated with CytoSorb use, this is the first study showing an increase in urinary output and a trend towards better survival among patients on VA ECMO treated with CytoSorb.

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.

Current clinical practice in using adjunctive extracorporeal blood purification in sepsis and septic shock: results from the ESICM "EXPLORATION" survey

BACKGROUND

Despite a lack of clear evidence extracorporeal blood purification (EBP) is increasingly used as an adjunctive treatment in septic shock based on its biological plausibility. However, current state of praxis and believes in both efficacy and level of evidence are very heterogeneous.

METHODS

The "EXPLORATION" (Current Clinical Practice in using adjunctive extracorporeal blood purification in septic shock), a web-based survey endorsed by the European Society of Intensive Care Medicine (ESICM), questioned both the current local clinical practices as well as future perspectives of EBP in sepsis and septic shock.

RESULTS

One hundred and two people participated in the survey. The majority of three quarters of participants (74.5%) use adjunctive EBP in their clinical routine with a varying frequency of description. Unselective cytokine adsorption (CA) (37.5%) and therapeutic plasma exchange (TPE) (34.1%) were by far the most commonly used modalities. While the overall theoretical rational was found to be moderate to high by the majority of the participants (74%), the effectively existing clinical evidence was acknowledged to be rather low (66%). Although CA was used most frequently in clinical practice, both the best existing clinical evidence endorsing its current use (45%) as well the highest potential to be explored in future clinical trials (51.5%) was attributed to TPE.

CONCLUSIONS

Although the majority of participants use EBP techniques in their clinical practice and acknowledge a subjective good theoretical rationale behind it, the clinical evidence is assessed to be limited. While both CA and TPE are by far the most common used technique, both clinical evidence as well as future potential for further exploration in clinical trials was assessed to be the highest for TPE.

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.

Impact of the matching algorithm on the treatment effect estimate: A neutral comparison study

Propensity score matching is increasingly being used in the medical literature. Choice of matching algorithms, reporting quality, and estimands are oftentimes not discussed. We evaluated the impact of propensity score matching algorithms, based on a recent clinical dataset, with three commonly used outcomes. The resulting estimands for different strengths of treatment effects were compared in a neutral comparison study and based on a thoroughly designed simulation study. Different algorithms yielded different levels of balance after matching. Along with full matching and genetic matching with replacement, good balance was achieved with nearest neighbor matching with caliper but thereby more than one fifth of the treated units were discarded. Average marginal treatment effect estimates were least biased with genetic or nearest neighbor matching, both with replacement and full matching. Double adjustment yielded conditional treatment effects that were closer to the true values, throughout. The choice of the matching algorithm had an impact on covariate balance after matching as well as treatment effect estimates. In comparison, genetic matching with replacement yielded better covariate balance than all other matching algorithms. A literature review in the British Medical Journal including its subjournals revealed frequent use of propensity score matching; however, the use of different matching algorithms before treatment effect estimation was only reported in one out of 21 studies. Propensity score matching is a methodology for causal treatment effect estimation from observational data; however, the methodological difficulties and low reporting quality in applied medical research need to be addressed.

[Pathophysiology of Acute Respiratory Distress Syndrome]

Acute respiratory distress syndrome (ARDS) is a common condition in intensive care medicine. Various intra- and extrapulmonal causes may trigger an epithelial and endothelial permeability increase, which leads to impaired gas exchange due to fluid overload of the alveoli and transmigration of leukocytes. This results in hypoxemia and hypercapnia, as well as deleterious consequences for the macro- and microcirculation with the risk of multi-organ failure and high mortality. This review summarizes ARDS pathophysiology and clinical consequences.

The Effect of CytoSorb on Inflammatory Markers in Critically Ill Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVES

The effectiveness of CytoSorb at removing inflammatory mediators in critically ill patients is controversial.

DATA SOURCES

Electronic databases were searched from inception to May 2023.

STUDY SELECTION

Randomized controlled trials reporting the effects of CytoSorb therapy on inflammatory parameters in critically ill patients with hyperinflammatory conditions were included.

DATA EXTRACTION

Two authors screened articles for eligibility, extracted data, and assessed the risk of bias, conflicts of interest, and certainty of evidence (CoE). The primary outcome was interleukin (IL)-6 at 1 day after initiation of the therapy. Secondary outcomes included various inflammatory markers at 1, 2, 3, and 5 days and mortality. Data were pooled if at least three trials reported the outcome of interest. We conducted meta-analyses of the data using a random-effects model.

DATA SYNTHESIS

Seventeen trials ( n = 855) were included. Fourteen trials were judged to have notable concern about conflicts of interest. Seven trials were performed in medical ICU patients with hyperinflammatory conditions and 10 in complex cardiovascular surgery under cardiopulmonary bypass. Hemoadsorption with CytoSorb was not associated with lower IL-6 at 1 day (mean difference -5.98 [95% CI, -30.44 to 18.48] pg/mL), 2 days, 3 days, or 5 days after initiation of the treatment, as well as the concentration of procalcitionin. The levels of C-reactive protein were not lower with CytoSorb at 1, 2, and 3 days. The use of CytoSorb was associated with higher mortality at latest follow-up (relative risk = 1.22 [95% CI, 1.02-1.45]) and at 30 days. CoE ranged from low to very low.

CONCLUSIONS

The use of CytoSorb hemoadsorption in a mixed population of critically ill patients with hyperinflammatory conditions does not exhibit a consistent decrease in IL-6 and other inflammatory parameters within the first 5 days of treatment. The significant uncertainty surrounding these findings highlights the need for further investigations.

Blood Purification for Adult Patients With Severe Infection or Sepsis/Septic Shock: A Network Meta-Analysis of Randomized Controlled Trials

OBJECTIVES

This study aimed to conduct a comprehensive and updated systematic review with network meta-analysis (NMA) to assess the outcome benefits of various blood purification modalities for adult patients with severe infection or sepsis.

DATA SOURCES

We conducted a search of PubMed, MEDLINE, clinical trial registries, Cochrane Library, and Embase databases with no language restrictions.

STUDY SELECTION

Only randomized controlled trials (RCTs) were selected.

DATA EXTRACTION

The primary outcome was overall mortality. The secondary outcomes were the length of mechanical ventilation (MV) days and ICU stay, incidence of acute kidney injury (AKI), and kidney replacement therapy requirement.

DATA SYNTHESIS

We included a total of 60 RCTs with 4,595 participants, comparing 16 blood purification modalities with 17 interventions. Polymyxin-B hemoperfusion (relative risk [RR]: 0.70; 95% CI, 0.57-0.86) and plasma exchange (RR: 0.61; 95% CI, 0.42-0.91) were associated with low mortality (very low and low certainty of evidence, respectively). Because of the presence of high clinical heterogeneity and intransitivity, the potential benefit of polymyxin-B hemoperfusion remained inconclusive. The analysis of secondary outcomes was limited by the scarcity of available studies. HA330 with high-volume continuous venovenous hemofiltration (CVVH), HA330, and standard-volume CVVH were associated with shorter ICU stay. HA330 with high-volume CVVH, HA330, and standard-volume CVVH were beneficial in reducing MV days. None of the interventions showed a significant reduction in the incidence of AKI or the need for kidney replacement therapy.

CONCLUSIONS

Our NMA suggests that plasma exchange and polymyxin-B hemoperfusion may provide potential benefits for adult patients with severe infection or sepsis/septic shock when compared with standard care alone, but most comparisons were based on low or very low certainty evidence. The therapeutic effect of polymyxin-B hemoperfusion remains uncertain. Further RCTs are required to identify the specific patient population that may benefit from extracorporeal blood purification.

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.

[Hemoperfusion in anesthesia and intensive care medicine: benefits, risks, and evidence for different systems]

BACKGROUND

Hemoperfusion is a technique for the extracorporeal elimination of endogenous and exogenous toxins and harmful mediators by adsorption. It can be used as a stand-alone device, as part of a heart-lung machine or extracorporeal membrane oxygenation (ECMO) or, as is currently the case, integrated into a kidney replacement procedure. In the meantime, various suppliers offer devices with different technologies.

OBJECTIVE

The aim of this work was to evaluate the benefits, risks and evidence of the different systems, how they work and for which indications they are approved in Germany.

METHOD

To achieve this goal, a narrative assessment of the existing literature and guidelines for different indications was performed. The focus was on in vivo studies.

RESULTS

In principle, a distinction must be made in adsorption techniques between pure adsorption and the combination as adsorption and kidney replacement therapy. The adsorbers available in Germany include Cytosorb®, HA-330, Seraph®-100 and Toraymyxin. Combined procedures (adsorption and kidney replacement) are offered with coupled plasma filtration and adsorption (CPFA) and oXiris®. Most adsorbers have been developed for cytokine and endotoxin removal in patients with sepsis; however, to date, no randomized controlled trial (RCT) has demonstrated a survival benefit when using hemoperfusion. Therefore, the S3 guidelines for treatment of sepsis and the surviving sepsis campaign guidelines advise against its routine use. When the corona pandemic began, hemoperfusion was considered as a promising therapeutic approach. Cytosorb®, Seraph®-100, and oXiris® received emergency approval by the FDA to be used in critically ill patients with COVID-19, so questions arose about the appropriateness and importance of its use; however, the data generated did not show positive results, so its use cannot be recommended routinely either. In addition, they are not mentioned as a treatment option in the current guidelines. The use of adsorption procedures in patients with liver failure and rhabdomyolysis has only been rudimentarily studied, so any evidence is currently lacking. The only adsorber that has CE approval in Germany for both applications is Cytosorb®. In the next few years, studies will have to follow that investigate the efficacy and thus either justify or refute the use in clinical routine. Hemoperfusion procedures are used in the heart-lung machine as part of cardiac surgery for either cytokine or anticoagulant adsorption. No congruent data are available to support the use for the elimination of cytokines. If emergency cardiac surgery is required in a patient with pre-existing anticoagulation, hemoperfusion procedures can be used to prevent bleeding complications. Cytosorb® has CE approval for this indication. All available techniques are nonselective adsorption processes, so that adsorption of known and unknown substances can occur. Unintentional adsorption of drugs, such as various anti-infective agents is a relevant risk, especially when used in patients with sepsis.

DISCUSSION

Various adsorption systems can eliminate different known and unknown substances. Currently, there is a lack of evidence for all indications and systems to justify their routine use except in clinical trials. Future clinical trials should evaluate the potential benefits but also dangers, so that in the meantime the routine use can be justified or a recommendation against the use can be given.

Development of dual-mode ELISA based on ALP-catalyzed APP hydrolysis for IL-6 detection

Sensitive and accurate detection of interleukin 6 (IL-6) is crucial for the early diagnosis of cerebral infarction to improve patient survival rates. However, the low-abundance of IL-6 in cerebral infarction presents a significant challenge in developing effective diagnosis method. Herein, we studied and analyzed the strong fluorescence property of 4-aminophenol phosphate (APP) and developed an enzyme-linked immunosorbent assay (ELISA) for IL-6 detection. The detection was based on the integration of optical signal change induced by alkaline phosphatase (ALP)-catalyzed APP hydrolysis and ALP-mediated ELISA. The generated colorimetric signal of 4-aminophenol, APP hydrolysis product, was used for ELISA of IL-6 with a detection limit of 0.1 ng/mL, and the visual detection of IL-6 was achieved. The changes in APP fluorescence have a good linear relationship with the logarithm of IL-6 concentration in the range of 0.005 ng/mL to 5.0 ng/mL, with a detection limit of 0.001 ng/mL, which was 100 times lower than that of conventional pNPP-based ELISA. Furthermore, the constructed ELISA effectively distinguished between samples from patients with cerebral infarction and volunteers with non-cerebral infarction, and the severity of symptoms was well distinguished based on IL-6 measurement. The dual-mode ELISA demonstrated high feasibility of low-abundance biomarker detection and displayed good potential for accurate in vitro diagnosis.

Hemoadsorption as Adjuvant Therapy in Acute Respiratory Distress Syndrome (ARDS): A Systematic Review and Meta-Analysis

BACKGROUND

Acute respiratory distress syndrome (ARDS) is often a consequence of a dysregulated immune response; therefore, immunomodulation by extracorporeal cytokine removal has been increasingly used as an adjuvant therapy, but convincing data are still missing. The aim of this study was to investigate the effects of adjunctive hemoadsorption (HA) on clinical and laboratory outcomes in patients with ARDS.

METHODS

We performed a systematic literature search in PubMed, Embase, CENTRAL, Scopus, and Web of Science (PROSPERO: CRD42022292176). The population was patients receiving HA therapy for ARDS. The primary outcome was the change in PaO2/FiO2 before and after HA therapy. Secondary outcomes included the before and after values for C-reactive protein (CRP), lactate, interleukin-6 (IL-6), and norepinephrine (NE) doses.

RESULTS

We included 26 publications, with 243 patients (198 undergoing HA therapy and 45 controls). There was a significant improvement in PaO2/FiO2 ratio following HA therapy (MD = 68.93 [95%-CI: 28.79 to 109.06] mmHg, p = 0.005) and a reduction in CRP levels (MD = -45.02 [95%-CI: -82.64; -7.39] mg/dL, p = 0.026) and NE dose (MD = -0.24 [95%-CI: -0.44 to -0.04] μg/kg/min, p = 0.028).

CONCLUSIONS

Based on our findings, HA resulted in a significant improvement in oxygenation and a reduction in NE dose and CRP levels in patients treated with ARDS. Properly designed RCTs are still needed.

Efficacy of the Cytokine Adsorption Therapy in Patients with Severe COVID-19-Associated Pneumonia: Lesson Learned from a Prospective Observational Study

INTRODUCTION

Severe COVID-19 pneumonia can activate a cytokine storm. Hemoperfusion can reduce pro-inflammatory cytokines in sepsis but is still debated in the COVID-19 setting. Thus, we sought to investigate the benefits of HA-330 cytokine adsorption through clinical and laboratory outcomes.

METHODS

We conducted a single-center prospective observational study in adults with severe COVID-19 pneumonia admitted to the intensive care unit at Chiang Mai University Hospital (Chiang Mai, Thailand). Those with cytokine storms indicated by organ injury, including acute respiratory distress syndrome (ARDS), and high inflammatory markers were included. Patients treated with the HA-330 device were classified as a hemoperfusion group, while those without cytokine adsorption were classified as a control group. We compared the outcomes on day 7 after treatment and evaluated the factors associated with 60-day mortality.

RESULTS

A total of 112 patients were enrolled. Thirty-eight patients received hemoperfusion, while 74 patients did not. Baseline cytokine storm parameters were comparable. In univariate analysis, there was an improvement in clinical and laboratory effects from hemoperfusion therapy. In multivariate analysis, APACHE II score, SOFA score, PaO2/FiO2, the number of hemoperfusion sessions, the amount of blood purified, high-sensitivity C-reactive protein, and IL-6 were associated with mortality. Using at least 3 sessions of hemoperfusion could mitigate, the 60-day mortality (adjusted odds ratio 0.25, 95% confidence interval: 0.03-0.33, p = 0.001). By categorizing the amount of blood treated into 3 groups of <1 L/kg, 1-2 L/kg, and ≥2 L/kg, there was a linear dose-response association with survival, which was better in the higher volume purified (mortality 60% vs. 33.3% vs. 0%, respectively, p = 0.015).

CONCLUSIONS

The early initiation of HA-330 hemoperfusion could improve the severity score and laboratory outcomes of COVID-19 ARDS. The optimal dose of at least three sessions or the amount of blood purified greater than 1 L/kg was associated with a reduction in 60-day mortality.

Proceedings of the 2022 UAB CRRT Academy: Non-Invasive Hemodynamic Monitoring to Guide Fluid Removal with CRRT and Proliferation of Extracorporeal Blood Purification Devices

In 2022, we celebrated the 15th anniversary of the University of Alabama at Birmingham (UAB) Continuous Renal Replacement Therapy (CRRT) Academy, a 2-day conference attended yearly by an international audience of over 100 nephrology, critical care, and multidisciplinary trainees and practitioners. This year, we introduce the proceedings of the UAB CRRT Academy, a yearly review of select emerging topics in the field of critical care nephrology that feature prominently in the conference. First, we review the rapidly evolving field of non-invasive hemodynamic monitoring and its potential to guide fluid removal by renal replacement therapy (RRT). We begin by summarizing the accumulating data associating fluid overload with harm in critical illness and the potential for harm from end-organ hypoperfusion caused by excessive fluid removal with RRT, underscoring the importance of accurate, dynamic assessment of volume status. We describe four applications of point-of-care ultrasound used to identify patients in need of urgent fluid removal or likely to tolerate fluid removal: lung ultrasound, inferior vena cava ultrasound, venous excess ultrasonography, and Doppler of the left ventricular outflow track to estimate stroke volume. We briefly introduce other minimally invasive hemodynamic monitoring technologies before concluding that additional prospective data are urgently needed to adapt these technologies to the specific task of fluid removal by RRT and to learn how best to integrate them into practical fluid-management strategies. Second, we focus on the growth of novel extracorporeal blood purification devices, starting with brief reviews of the inflammatory underpinnings of multiorgan dysfunction and the specific applications of pathogen, endotoxin, and/or cytokine removal and immunomodulation. Finally, we review a series of specific adsorptive technologies, several of which have seen substantial clinical use during the COVID-19 pandemic, describing their mechanisms of target removal, the limited existing data supporting their efficacy, ongoing and future studies, and the need for additional prospective trials.

Impact of CytoSorb and CKRT on hemodynamics in pediatric patients with septic shock: the PedCyto study

Background

There is a lack of data to support the use of hemoadsorption in pediatric septic shock. The aim of our study was to assess the effectiveness and safety of CytoSorb therapy in this setting.

Methods

Phase II interventional single arm pilot study in which 17 consecutive children admitted with septic shock who required continuous kidney replacement therapy (CKRT) and weighed ≥10 kg were included. A CytoSorb (CytoSorbents Inc, New Jersey, USA) hemoadsorption cartridge was added to the CKRT every 24 h for a maximum of 96 h. A control group of 13 children with septic shock treated with CKRT but not hemoadsorption at Children's Hospital Bambino Gesù and enrolled in the EuroAKId register was selected as an historical cohort. The primary outcome of the study was a reduction in vasopressor or inotrope dose of >50% from baseline by the end of CytoSorb therapy. Secondary outcomes included hemodynamic and biological changes, changes in severity scores, and 28-day mortality.

Results

There were significant decreases in the Vasoactive Inotropic Score (VIS) and the Pediatric Logistic Organ Dysfunction 2 (PELOD-2) score at 72 and 96 h from the start of the CytoSorb therapy compared to baseline; the reductions were larger in the hemoadsorption group than in the control group (historical cohort). 28-day mortality was lower, although not significantly, in the hemoadsorption group when compared to the control group (5/17 [29%] vs. 8/13 [61%] OR 0.26 [95% CI: 0.05-1.2]; p = 0.08).

Conclusions

CytoSorb therapy may have some benefits in pediatric patients with septic shock. Future larger randomized trials are needed in this setting.

Clinical Trial Registration

https://clinicaltrials.gov/ct2/show/NCT05658588, identifier (Clinicaltrials.gov NCT05658588).

Extracorporeal Blood Purification with CytoSorb in 359 Critically Ill Patients

INTRODUCTION

Critically ill patients with inflammatory dysregulation and organ disfunction may benefit from blood purification, although the use of this technique has not been described in large case series. We evaluated clinical outcomes and survival in high-risk intensive care unit (ICU) patients who underwent extracorporeal blood purification.

METHODS

359 consecutive ICU patients treated with CytoSorb were included.

RESULTS

Main admission diagnoses were 120 (34%) refractory cardiac arrest under mechanical chest compression; 101 (28%) profound cardiogenic shock; 81 (23%) post-cardiotomy cardiogenic shock; and 37 (10%) respiratory failure. Fifteen patients (4%) were positive for SARS-CoV-2 infection. We observed 49% 30-day mortality, 57% ICU mortality, and 62% hospital mortality, all lower than the 71% mortality predicted by SAPS II and 68% predicted by SOFA score. Parameters of shock and organ failure, above all vasoactive inotropic score, reduced during CytoSorb treatment. Multivariable analysis identified SAPS II, lactate dehydrogenase, ICU stay duration, vasoactive inotropic score, lactates, intra-aortic counterpulsation on top of VA-ECMO, and total bilirubin as predictors of mortality. No CytoSorb-related complications occurred.

CONCLUSION

CytoSorb treatment was effective in reducing laboratory parameters of shock and vasoactive inotropic score with possible survival implications in a large population of critically ill patients.

Extracorporeal blood purification therapies for sepsis-associated acute kidney injury in critically ill patients: expert opinion from the SIAARTI-SIN joint commission

Sepsis-Associated Acute Kidney Injury is a life-threatening condition leading to high morbidity and mortality in critically ill patients admitted to the intensive care unit. Over the past decades, several extracorporeal blood purification therapies have been developed for both sepsis and sepsis-associated acute kidney injury management. Despite the widespread use of extracorporeal blood purification therapies in clinical practice, it is still unclear when to start this kind of treatment and how to define its efficacy. Indeed, several questions on sepsis-associated acute kidney injury and extracorporeal blood purification therapy still remain unresolved, including the indications and timing of renal replacement therapy in patients with septic vs. non-septic acute kidney injury, the optimal dialysis dose for renal replacement therapy modalities in sepsis-associated acute kidney injury patients, and the rationale for using extracorporeal blood purification therapies in septic patients without acute kidney injury. Moreover, the development of novel extracorporeal blood purification therapies, including those based on the use of adsorption devices, raised the attention of the scientific community both on the clearance of specific mediators released by microorganisms and by injured cells and potentially involved in the pathogenic mechanisms of organ dysfunction including sepsis-associated acute kidney injury, and on antibiotic removal. Based on these considerations, the joint commission of the Italian Society of Anesthesiology and Critical Care (SIAARTI) and the Italian Society of Nephrology (SIN) herein addressed some of these issues, proposed some recommendations for clinical practice and developed a common framework for future clinical research in this field.

Venovenous extracorporeal membrane oxygenation for coronavirus disease 2019 patients: A systematic review and meta-analysis

OBJECTIVE

Although the application of venovenous extracorporeal membrane oxygenation (VV-ECMO) in coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome (ARDS) is accumulating, the feasibility and safety of this therapy remain controversial. We aimed to evaluate the effect of VV-ECMO in the treatment of these patients.

METHODS

A comprehensive literature search was performed using PubMed, Embase, the Cochrane Library, and International Clinical Trials Registry Platform databases through November 2021. According to the inclusion and exclusion criteria, the included studies were screened, and meta-analysis was performed by R software (version 4.0.2).

RESULTS

Forty-two studies including 2037 COVID-19 patients supported with VV-ECMO due to ARDS were identified. The pooled analysis revealed that 30-, 60-, and 90-day mortality among patients were respectively 46% (95% CI 37%-57%, I2 = 66%), 46% (95% CI 30%-70%, I2 = 93%), and 49% (95% CI 43%-58%, I2 = 52%), and the pooled incidence rate of in-hospital mortality, major bleeding, hemorrhagic stroke, thrombosis, pulmonary embolism, deep venous thrombosis, and renal replacement therapy were respectively 35%, 39%, 11%, 40%, 15%, 21%, and 44%.

CONCLUSION

Although COVID-19 patients may have a higher risk of bleeding, hemorrhagic stroke, and acute kidney injury during ECMO therapy, the survival rate was more than half of the cases. Our data may support the application of VV-ECMO in COVID-19 patients.

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.

A matched case-control study on the effectiveness of extracorporeal cytokine adsorption in critically ill patients

Extracorporeal cytokine adsorption aims to reduce cytokine levels in critically ill patients. However, little convincing data exist to support its widespread use. This retrospective study compared interleukin-6 (IL-6) levels in patients treated with or without cytokine adsorber (CytoSorb®). Intensive care patients between Jan 2017 and Dec 2021 who had at least two IL-6 measurements were included. They were divided into an adsorber group and a standard of care group. We screened 3865 patients and included 52 patients in the adsorber group and 94 patients in the standard of care group. Matching was performed and the groups were compared regarding IL-6, lactate, CRP, procalcitonin, vasopressor requirement, and mortality rate. After matching, there were 21 patients in each group. Patients had similar age, ECMO and renal replacement therapy use, baseline noradrenaline requirement, serum lactate, pH, CRP, and IL-6 levels. There were no significant differences in the time course of IL-6, lactate, CRP, procalcitonin and noradrenaline requirement between groups. Two-day and ICU mortality and Kaplan-Meier estimated survival were also comparable. In this matched case-control study no difference in IL-6, inflammatory parameters, noradrenaline requirement or mortality was observed between patients treated with adsorber or standard of care.

Targeting cytokine storm as the potential anti-viral therapy: Implications in regulating SARS-CoV-2 pathogenicity

The latest global pandemic corona virus disease - 2019 (COVID-19) caused by the virus SARS-CoV-2 is still a matter of worrying concern both for the scientific communities and health care organizations. COVID-19 disease is proved to be a highly contagious disease transmitted through respiratory droplets and even close contact with affected individuals. COVID-19 disease is also understood to exhibit diverse symptoms of ranging severities i.e., from mild fatigue to death. Affected individuals' susceptibility to induce immunologic dysregulation phenomena termed 'cytokine storm' seems to be playing the damaging role of escalating the disease manifestation from mild to severe. Cytokine storm in patients with severe symptoms is understood to be characterized by enhanced serum levels of many cytokines including interleukin-1β, interleukin-6, IL-10, TNF, interferon-γ, MIP-1α, MIP-1β and VEGF. Since cytokine production in general is the most important antiviral defense response, understanding the COVID-19 associated cytokine storm in particular and differentiating it from the regular cytokine production response becomes crucial in developing an effective therapeutic strategy.This review focuses on the potential targeting of COVID-19 associated cytokine storm and its challenges.

Inflammatory Biomarkers Affecting Survival Prognosis in Patients Receiving Veno-Venous ECMO for Severe COVID-19 Pneumonia

Severe COVID-19 pneumonia in which mechanical ventilation is unable to achieve adequate gas exchange can be treated with veno-venous ECMO, eliminating the need for aggressive mechanical ventilation which might promote ventilator-induced lung injury and increase mortality. In this retrospective observational study, 18 critically ill COVID-19 patients who were treated using V-V ECMO during an 11-month period in a tertiary COVID-19 hospital were analyzed. Biomarkers of inflammation and clinical features were compared between survivors and non-survivors. Survival rates were compared between patients receiving ECMO and propensity matched mechanically ventilated controls. There were 7 survivors and 11 non-survivors. The survivors were significantly younger, with a higher proportion of females, higher serum procalcitonin at ICU admission, and before initiation of ECMO they had significantly lower Murray scores, PaCO₂, WBC counts, serum ferritin levels, and higher glomerular filtration rates. No significant difference in mortality was found between patients treated with ECMO compared to patients treated using conventional lung protective ventilation. Hypercapnia, leukocytosis, reduced glomerular filtration rate, and increased serum ferritin levels prior to initiation of V-V ECMO in patients with severe COVID-19 pneumonia may be early warning signs of reduced chance of survival. Further multicentric studies are needed to confirm 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.

Hemoadsorption in Heart Failure Requiring Mechanical Circulatory Support-A Systematic Review and Meta-Analysis

Background

Left ventricular assist devices (LVAD) and extracorporeal membrane oxygenation (ECMO) are well established therapies in heart failure (HF) management. Their use is generally associated with a sudden increase in inflammatory mediators, which are often already elevated in patients with HF prior to device implantation. An exaggerated release of proinflammatory cytokines is associated with organ dysfunction and increased mortality. Hemoadsorption has been shown to reduce inflammatory mediators during cardiopulmonary bypass.

Objective

To investigate the role of hemoadsorption during the management of acute or chronic heart failure with mechanical circulatory support and its impact on survival.

Methods

We systematically searched MEDLINE selecting all studies comparing the use of hemoadsorption during LVAD implantation or veno-arterial (v.a.) ECMO therapy. Records were screened by two different investigators. Reports without a control group and duplicates were excluded.

Results

Our search delivered six studies. One was randomized and five were retrospective studies, of which three were risk-adjusted. During LVAD implantation, one study showed no difference in mortality but higher incidence of respiratory insufficiency in the hemoadsorption group (54% vs 30%, p = 0.024) and the other study found higher mortality in the hemoadsorption group (33% vs 0%, p = 0.01). During ECMO therapy, three of four studies including the randomized one found no difference in survival or major adverse cardiac events between the hemoadsorption and the control groups. Only one study found lower mortality in the hemoadsorption group (20% vs 60%. p = 0.02).

Conclusions

The results of this literature review suggest that the use of hemoadsorption in patients undergoing LVAD implantation might be associated with higher morbidity and mortality. The majority of studies on the use of hemoadsorption during v.a. ECMO therapy showed no effect on mortality or organ dysfunction, while only one small study showed that hemoadsorption was able to reduce mortality. The results are limited by the retrospective nature and the small sample sizes of the majority of the studies included.

Hemadsorption in patients requiring V-A ECMO support: Comparison of Cytosorb versus Jafron HA330

BACKGROUND

ECMO support is associated with the development of a systemic hyper-inflammatory response, which may become quite significant and extreme in some cases. We hypothesize that Cytosorb or Jafron therapy may benefit patients on V-A ECMO in terms of levels of inflammatory markers such as IL-6, complications, and overall outcomes.

METHODS

We conducted a retrospective study of prospectively collected data in a single tertiary care center between January 2021 and April 2022. At the time of the analysis of this article, 20 patients on V-A ECMO had cytokine adsorption while on ECMO support: Cytosorb group (n = 10), Jafron group (n = 10). In 10 ECMO-supported patients cytokine adsorption was not used, this group served as a control group, which may be quite significant in some cases. Evaluation of the level of inflammatory markers (IL-1, 6, 8; CRP, Leukocyte, Lactate, PCT, NT-proBNP, TNF-α) was performed.

RESULTS

There was statistically significant longer CPB time, aortic cross-clamp time and ICU stay in cytokine adsorption groups than in the control group, but there were no differences between subgroups with different types of haemoadsorption used. Moreover, in the control group mortality rate was higher than in the cytokine adsorption groups (60% vs. 20%, p = 0.02). All patients had an elevation of inflammatory markers in the perioperative and immediate postoperative periods. After 72 h of intensive care, blood inflammation markers had a tendency to decline.

CONCLUSION

At the time of writing, hemadsorption in patients requiring V-A ECMO support represents a good therapeutic effect. This effect is permanent for the whole period of extracorporeal cytokine hemadsorption application for both CytoSorb and Jafron HA330 devices.

Mortality rates of severe COVID-19-related respiratory failure with and without extracorporeal membrane oxygenation in the Middle Ruhr Region of Germany

The use of extracorporeal membrane oxygenation (ECMO) is discussed to improve patients' outcome in severe COVID-19 with respiratory failure, but data on ECMO remains controversial. The aim of the study was to determine the characteristics of patients under invasive mechanical ventilation (IMV) with or without veno-venous ECMO support and to evaluate outcome parameters. Ventilated patients with COVID-19 with and without additional ECMO support were analyzed in a retrospective multicenter study regarding clinical characteristics, respiratory and laboratory parameters in day-to-day follow-up. Recruitment of patients was conducted during the first three COVID-19 waves at four German university hospitals of the Ruhr University Bochum, located in the Middle Ruhr Region. From March 1, 2020 to August 31, 2021, the charts of 149 patients who were ventilated for COVID-19 infection, were included (63.8% male, median age 67 years). Fifty patients (33.6%) received additional ECMO support. On average, ECMO therapy was initiated 15.6 ± 9.4 days after symptom onset, 10.6 ± 7.1 days after hospital admission, and 4.8 ± 6.4 days after the start of IMV. Male sex and higher SOFA and RESP scores were observed significantly more often in the high-volume ECMO center. Pre-medication with antidepressants was more often detected in survivors (22.0% vs. 6.5%; p = 0.006). ECMO patients were 14 years younger and presented a lower rate of concomitant cardiovascular diseases (18.0% vs. 47.5%; p = 0.0004). Additionally, cytokine-adsorption (46.0% vs. 13.1%; p < 0.0001) and renal replacement therapy (76.0% vs. 43.4%; p = 0.0001) were carried out more frequently; in ECMO patients thrombocytes were transfused 12-fold more often related to more than fourfold higher bleeding complications. Undulating C-reactive protein (CRP) and massive increase in bilirubin levels (at terminal stage) could be observed in deceased ECMO patients. In-hospital mortality was high (Overall: 72.5%, ECMO: 80.0%, ns). Regardless of ECMO therapy half of the study population deceased within 30 days after hospital admission. Despite being younger and with less comorbidities ECMO therapy did not improve survival in severely ill COVID-19 patients. Undulating CRP levels, a massive increase of bilirubin level and a high use of cytokine-adsorption were associated with worse outcomes. In conclusion, ECMO support might be helpful in selected severe cases of COVID-19.

Survival of Patients Treated With Extracorporeal Hemoadsorption and Extracorporeal Membrane Oxygenation: Results From a Nation-Wide Registry

Extracorporeal hemoadsorption with the CytoSorb adsorber is increasingly being used during the past years. The use in combination with extracorporeal membrane oxygenation (ECMO) is feasible, but frequency of its use and outcomes have not been assessed in larger cohorts. We analyzed all patients treated with veno-venous (VV) ECMO either with or without CytoSorb in Germany from 2017 to 2019. Data were retrieved from a nationwide claim dataset collected by the Research Data Center of the Federal Bureau of Statistics. During this three-year episode, 7,699 patients were treated with VV ECMO. Among these, the number of CytoSorb-treated patients constantly increased from 156 (6.6%) in 2017 to 299 (11.8%) in 2019. In this large cohort hemoadsorption with the CytoSorb adsorber was associated with higher mortality and increased treatment costs. Due to limited information in the dataset about the severity of disease comparison of outcomes of patients treated with and without CytoSorb has to be interpreted with caution. Further studies have to examine if this finding is due to a negative effect of hemoadsorption with the CytoSorb device or is rather to be attributed to disease severity.

Targeting circulating high mobility group box-1 and histones by extracorporeal blood purification as an immunomodulation strategy against critical illnesses

Both high mobility group box-1 (HMGB1) and histones are major damage-associated molecular patterns (DAPMs) that mediate lethal systemic inflammation, activation of the complement and coagulation system, endothelial injury and multiple organ dysfunction syndrome in critical illnesses. Although accumulating evidence collectively shows that targeting HMGB1 or histones by their specific antibodies or inhibitors could significantly mitigate aberrant immune responses in multiple critically ill animal models, routine clinical use of such agents is still not recommended by any guideline. In contrast, extracorporeal blood purification, which has been widely used to replace dysfunctional organs and remove exogenous or endogenous toxins in intensive care units, may also exert an immunomodulatory effect by eliminating inflammatory mediators such as cytokines, endotoxin, HMGB1 and histones in patients with critical illnesses. In this review, we summarize the multiple immunopathological roles of HMGB1 and histones in mediating inflammation, immune thrombosis and organ dysfunction and discuss the rationale for the removal of these DAMPs using various hemofilters. The latest preclinical and clinical evidence for the use of extracorporeal blood purification to improve the clinical outcome of critically ill patients by targeting circulating HMGB1 and histones is also gathered.

Rationale for sequential extracorporeal therapy (SET) in sepsis

Sepsis and septic shock remain drivers for morbidity and mortality in critical illness. The clinical picture of patients presenting with these syndromes evolves rapidly and may be characterised by: (a) microbial host invasion, (b) establishment of an infection focus, (c) opsonisation of bacterial products (e.g. lipopolysaccharide), (d) recognition of pathogens resulting in an immune response, (e) cellular and humoral effects of circulating pathogen and pathogen products, (f) immunodysregulation and endocrine effects of cytokines, (g) endothelial and organ damage, and (h) organ crosstalk and multiple organ dysfunction. Each step may be a potential target for a specific therapeutic approach. At various stages, extracorporeal therapies may target circulating molecules for removal. In sequence, we could consider: (a) pathogen removal from the circulation with affinity binders and cartridges (specific), (b) circulating endotoxin removal by haemoperfusion with polymyxin B adsorbers (specific), (c) cytokine removal by haemoperfusion with sorbent cartridges or adsorbing membranes (non-specific), (d) extracorporeal organ support with different techniques for respiratory and cardiac support (CO₂ removal or extracorporeal membrane oxygenation), and renal support (haemofiltration, haemodialysis, or ultrafiltration). The sequence of events and the use of different techniques at different points for specific targets will likely require trials with endpoints other than mortality. Instead, the primary objectives should be to achieve the desired action by using extracorporeal therapy at a specific point.

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.