Cytokine adsorption in severe, refractory septic shock

CVVHDF combined with cytokine adsorption column ameliorates severe catheter-related bloodstream infection in a hemodialysis patient

In extracorporeal circulation, inflammatory mediators are eliminated through inflammatory cytokine adsorption. By interacting with inflammatory cytokines and removing them from the bloodstream, the adsorber's adsorbent lowers levels of inflammatory mediators and the inflammatory response. We present the case of a 67-year-old Chinese man diagnosed with sepsis due to a bloodstream infection from a catheter. We promptly utilized a cytokine adsorption column in conjunction with continuous veno-venous hemodiafiltration (CVVHDF), resulting in a decrease in interleukin-6 levels and complete removal of bascteria from the bloodstream. A critical turning point in illness management is reached as the levels of inflammatory cytokines drop and the dosage of patients' vasoactive medications improves significantly. In hemodialysis patients with secondary septic shock in the context of catheter-associated bacteremia, the combination of CVVHDF with cytokine adsorption therapy in hemodialysis may be clinically useful and improve or accelerate the patient's improvement.

Current perspectives in the management of sepsis and septic shock

Within patients with sepsis, there exists significant heterogeneity, and while all patients should receive conventional therapy, there are subgroups of patients who may benefit from specific therapies, often referred to as rescue therapies. Therefore, the identification of these specific patient subgroups is crucial and lays the groundwork for the application of precision medicine based on the development of targeted interventions. Over the years, efforts have been made to categorize sepsis into different subtypes based on clinical characteristics, biomarkers, or underlying mechanisms. For example, sepsis can be stratified into different phenotypes based on the predominant dysregulated host response. These phenotypes can range from hyperinflammatory states to immunosuppressive states and even mixed phenotypes. Each phenotype may require different therapeutic approaches to improve patient outcomes. Rescue strategies for septic shock may encompass various interventions, such as immunomodulatory therapies, extracorporeal support (e.g., ECMO), or therapies targeted at specific molecular or cellular pathways involved in the pathophysiology of sepsis. In recent years, there has been growing interest in precision medicine approaches to sepsis and phenotype identification. Precision medicine aims to tailor treatments to each individual patient based on their unique characteristics and disease mechanisms.

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.

Towards personalized medicine: a scoping review of immunotherapy in sepsis

Despite significant progress in our understanding of the pathophysiology of sepsis and extensive clinical research, there are few proven therapies addressing the underlying immune dysregulation of this life-threatening condition. The aim of this scoping review is to describe the literature evaluating immunotherapy in adult patients with sepsis, emphasizing on methods providing a "personalized immunotherapy" approach, which was defined as the classification of patients into a distinct subgroup or subphenotype, in which a patient's immune profile is used to guide treatment. Subgroups are subsets of sepsis patients, based on any cut-off in a variable. Subphenotypes are subgroups that can be reliably discriminated from other subgroup based on data-driven assessments. Included studies were randomized controlled trials and cohort studies investigating immunomodulatory therapies in adults with sepsis. Studies were identified by searching PubMed, Embase, Cochrane CENTRAL and ClinicalTrials.gov, from the first paper available until January 29th, 2024. The search resulted in 15,853 studies. Title and abstract screening resulted in 1409 studies (9%), assessed for eligibility; 771 studies were included, of which 282 (37%) were observational and 489 (63%) interventional. Treatment groups included were treatments targeting the innate immune response, the complement system, coagulation and endothelial dysfunction, non-pharmalogical treatment, pleiotropic drugs, immunonutrition, concomitant treatments, Traditional Chinese Medicine, immunostimulatory cytokines and growth factors, intravenous immunoglobulins, mesenchymal stem cells and immune-checkpoint inhibitors. A personalized approach was incorporated in 70 studies (9%). Enrichment was applied using cut-offs in temperature, laboratory, biomarker or genetic variables. Trials often showed conflicting results, possibly due to the lack of patient stratification or the potential influence of severity and timing on immunomodulatory therapy results. When a personalized approach was applied, trends of clinical benefit for several interventions emerged, which hold promise for future clinical trials using personalized immunotherapy.

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.

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.

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.

Effects of enhanced adsorption haemofiltration versus haemoadsorption in severe, refractory septic shock with high levels of endotoxemia: the ENDoX bicentric, randomized, controlled trial

BACKGROUND

Endotoxin adsorption is a promising but controversial therapy in severe, refractory septic shock and conflicting results exist on the effective capacity of available devices to reduce circulating endotoxin and inflammatory cytokine levels.

METHODS

Multiarm, randomized, controlled trial in two Swiss intensive care units, with a 1:1:1 randomization of patients suffering severe, refractory septic shock with high levels of endotoxemia, defined as an endotoxin activity ≥ 0.6, a vasopressor dependency index ≥ 3, volume resuscitation of at least 30 ml/kg/24 h and at least single organ failure, to a haemoadsorption (Toraymyxin), an enhanced adsorption haemofiltration (oXiris) or a control intervention. Primary endpoint was the difference in endotoxin activity at 72-h post-intervention to baseline. In addition, inflammatory cytokine, vasopressor dependency index and SOFA-Score dynamics over the initial 72 h were assessed inter alia.

RESULTS

In the 30, out of 437 screened, randomized patients (10 Standard of care, 10 oXiris, 10 Toraymyxin), endotoxin reduction at 72-h post-intervention-start did not differ among interventions (Standard of Care: 12 [1-42]%, oXiris: 21 [10-51]%, Toraymyxin: 23 [10-36]%, p = 0.82). Furthermore, no difference between groups could be observed neither for reduction of inflammatory cytokine levels (p = 0.58), nor for vasopressor weaning (p = 0.95) or reversal of organ injury (p = 0.22).

CONCLUSIONS

In a highly endotoxemic, severe, refractory septic shock population neither the Toraymyxin adsorber nor the oXiris membrane could show a reduction in circulating endotoxin or cytokine levels over standard of care. Trial registration ClinicalTrials.gov. NCT01948778. Registered August 30, 2013. https://clinicaltrials.gov/study/NCT01948778.

Targeting the host response in sepsis: current approaches and future evidence

Sepsis, a dysregulated host response to infection characterized by organ failure, is one of the leading causes of death worldwide. Disbalances of the immune response play an important role in its pathophysiology. Patients may develop simultaneously or concomitantly states of systemic or local hyperinflammation and immunosuppression. Although a variety of effective immunomodulatory treatments are generally available, attempts to inhibit or stimulate the immune system in sepsis have failed so far to improve patients' outcome. The underlying reason is likely multifaceted including failure to identify responders to a specific immune intervention and the complex pathophysiology of organ dysfunction that is not exclusively caused by immunopathology but also includes dysfunction of the coagulation system, parenchymal organs, and the endothelium. Increasing evidence suggests that stratification of the heterogeneous population of septic patients with consideration of their host response might led to treatments that are more effective. The purpose of this review is to provide an overview of current studies aimed at optimizing the many facets of host response and to discuss future perspectives for precision medicine approaches in sepsis.

[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.

Substantial heterogeneity of inflammatory cytokine production and its inhibition by a triple cocktail of toll-like receptor blockers in early sepsis

Introduction

Early sepsis is a life-threatening immune dysregulation believed to feature a "cytokine storm" due to activation of pattern recognition receptors by pathogen and danger associated molecular patterns. However, treatments with single toll-like receptor (TLR) blockers have shown no clinical benefit. We speculated that sepsis patients at the time of diagnosis are heterogeneous in relation to their cytokine production and its potential inhibition by a triple cocktail of TLR blockers. Accordingly, we analyzed inflammatory cytokine production in whole blood assays from early sepsis patients and determined the effects of triple TLR-blockade.

Methods

Whole blood of 51 intensive care patients sampled within 24h of meeting Sepsis-3 criteria was incubated for 6h without or with specific TLR2, 4, and 7/8 stimuli or suspensions of heat-killed S. aureus or E. coli bacteria as pan-TLR challenges, and also with a combination of monoclonal antibodies against TLR2 and 4 and chloroquine (endosomal TLR inhibition), subsequent to dose optimization. Concentrations of tumor necrosis factor (TNF), Interleukin(IL)-6, IL-8, IL-10, IL-1α and IL-1β were measured (multiplex ELISA) before and after incubation. Samples from 11 sex and age-matched healthy volunteers served as controls and for dose-finding studies.

Results

Only a fraction of sepsis patient samples revealed ongoing cytokine production ex vivo despite sampling within 24 h of first meeting Sepsis-3 criteria. In dose finding studies, inhibition of TLR2, 4 and endosomal TLRs reliably suppressed cytokine production to specific TLR agonists and added bacteria. However, inflammatory cytokine production ex vivo was only suppressed in the high cytokine producing samples but not in the majority. The suppressive response to TLR-blockade correlated both with intraassay inflammatory cytokine production (r=0.29-0.68; p<0.0001-0.04) and cytokine baseline concentrations (r=0.55; p<0.0001).

Discussion

Upon meeting Sepsis-3 criteria for less than 24 h, a mere quarter of patient samples exhibits a strong inflammatory phenotype, as characterized by increased baseline inflammatory cytokine concentrations and a stark TLR-dependent increase upon further ex vivo incubation. Thus, early sepsis patient cohorts as defined by Sepsis-3 criteria are very heterogeneous in regard to inflammation. Accordingly, proper ex vivo assays may be useful in septic individuals before embarking on immunomodulatory treatments.

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.

Haemoadsorption Combined with Continuous Renal Replacement Therapy in Abdominal Sepsis: Case Report Series

In recent decades, multiple efforts have been made to identify targets and therapeutic measures in the host response to infection. Haemoadsorption, under the attractive theoretical premise of inflammatory response modulation through the adsorption of soluble inflammatory mediators, could have a place as an adjuvant therapy in septic patients. The development of new devices and the recent COVID-19 pandemic has renewed interest in this therapy. The aim of this report is to describe our experience in patients with abdominal sepsis for whom haemoadsorption with a neutral microporous resin column was added to conventional treatment and to describe its performance through patient cases in the absence of large randomised trials with this device. We present five patients with abdominal sepsis admitted to a Spanish intensive care unit in which haemoadsorption was used as adjuvant treatment. The key practical aspects of the treatment protocol have been used as a guide for conducting a multicentric study. Based on the experience gathered in these five cases, the potential benefit of haemoadsorption as adjuvant therapy in patients with abdominal sepsis with multiple organ failure after control of the source of infection and adequate treatment should be investigated. Likewise, it must be defined which patients can benefit from the therapy, the most appropriate biomarkers to guide the therapy, the ideal time of initiation and discontinuation, its potential side effects, and the interaction with other therapies, especially how such treatment affects the antibiotics levels.

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.

Research priorities for therapeutic plasma exchange in critically ill patients

Therapeutic plasma exchange (TPE) is a therapeutic intervention that separates plasma from blood cells to remove pathological factors or to replenish deficient factors. The use of TPE is increasing over the last decades. However, despite a good theoretical rationale and biological plausibility for TPE as a therapy for numerous diseases or syndromes associated with critical illness, TPE in the intensive care unit (ICU) setting has not been studied extensively. A group of eighteen experts around the globe from different clinical backgrounds used a modified Delphi method to phrase key research questions related to "TPE in the critically ill patient". These questions focused on: (1) the pathophysiological role of the removal and replacement process, (2) optimal timing of treatment, (3) dosing and treatment regimes, (4) risk-benefit assumptions and (5) novel indications in need of exploration. For all five topics, the current understanding as well as gaps in knowledge and future directions were assessed. The content should stimulate future research in the field and novel clinical applications.

Extracorporeal blood purification strategies in sepsis and septic shock: An insight into recent advancements

BACKGROUND

Despite various therapies to treat sepsis, it is one of the leading causes of mortality in the intensive care unit patients globally. Knowledge about the pathophysiology of sepsis has sparked interest in extracorporeal therapies (ECT) which are intended to balance the dysregulation of the immune system by removing excessive levels of inflammatory mediators.

AIM

To review recent data on the use of ECT in sepsis and to assess their effects on various inflammatory and clinical outcomes.

METHODS

In this review, an extensive English literature search was conducted from the last two decades to identify the use of ECT in sepsis. A total of 68 articles from peer-reviewed and indexed journals were selected excluding publications with only abstracts.

RESULTS

Results showed that ECT techniques such as high-volume hemofiltration, coupled plasma adsorption/filtration, resin or polymer adsorbers, and CytoSorb^® are emerging as adjunct therapies to improve hemodynamic stability in sepsis. CytoSorb^® has the most published data in regard to the use in the field of septic shock with reports on improved survival rates and lowered sequential organ failure assessment scores, lactate levels, total leucocyte count, platelet count, interleukin- IL-6, IL-10, and TNF levels.

CONCLUSION

Clinical acceptance of ECT in sepsis and septic shock is currently still limited due to a lack of large random clinical trials. In addition to patient-tailored therapies, future research developments with therapies targeting the cellular level of the immune response are expected.

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.

The Techniques of Blood Purification in the Treatment of Sepsis and Other Hyperinflammatory Conditions

Even in the absence of strong indications deriving from clinical studies, the removal of mediators is increasingly used in septic shock and in other clinical conditions characterized by a hyperinflammatory response. Despite the different underlying mechanisms of action, they are collectively indicated as blood purification techniques. Their main categories include blood- and plasma processing procedures, which can run in a stand-alone mode or, more commonly, in association with a renal replacement treatment. The different techniques and principles of function, the clinical evidence derived from multiple clinical investigations, and the possible side effects are reviewed and discussed along with the persisting uncertainties about their precise role in the therapeutic armamentarium of these syndromes.

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.

Application of oXiris-continuous hemofiltration adsorption in patients with sepsis and septic shock: A single-centre experience in China

oXiris is a new, high-adsorption membrane filter in continuous hemofiltration adsorption to reduce the inflammatory response in sepsis. The investigators retrospectively reviewed patients with sepsis/septic shock who underwent at least one oXiris-treatment from November 2020 to March 2022. The demographic data, baseline levels before treatment, clinical datas, prognosis, and the occurrence of adverse events during treatment were recorded. 90 patients were enrolled in this study. The hemodynamic indices, sequential organ failure assessment score, lactate, inflammatory biomarkers levels were significantly improved at 12 h and 24 h after treatment. Procalcitonin and interleukin-6 reduction post-treatment of oXiris were most pronounced in infection from skin and soft tissue, urinary and abdominal cavity. Logistic regression analysis showed that pre-treatment sequential organ failure assessment score (p = 0.034), percentage decrease in sequential organ failure assessment score (p = 0.004), and age (p = 0.011) were independent risk factors for intensive care unit mortality. In conclusion, oXiris-continuous hemofiltration adsorption may improve hemodynamic indicators, reduce the use of vasoactive drugs, reduce lactate level and infection indicators. Of note, oXiris improve organ function in sepsis, which may result to higher survival rate.

Extracorporeal immune cell therapy of sepsis: ex vivo results

BACKGROUND

Immune cell dysfunction plays a central role in sepsis-associated immune paralysis. The transfusion of healthy donor immune cells, i.e., granulocyte concentrates (GC) potentially induces tissue damage via local effects of neutrophils. Initial clinical trials using standard donor GC in a strictly extracorporeal bioreactor system for treatment of septic shock patients already provided evidence for beneficial effects with fewer side effects, by separating patient and donor immune cells using plasma filters. In this ex vivo study, we demonstrate the functional characteristics of a simplified extracorporeal therapy system using purified granulocyte preparations.

METHODS

Purified GC were used in an immune cell perfusion model prefilled with human donor plasma simulating a 6-h treatment. The extracorporeal circuit consisted of a blood circuit and a plasma circuit with 3 plasma filters (PF). PF1 is separating the plasma from the patient's blood. Plasma is then perfused through PF2 containing donor immune cells and used in a dead-end mode. The filtrated plasma is finally retransfused to the blood circuit. PF3 is included in the plasma backflow as a redundant safety measure. The donor immune cells are retained in the extracorporeal system and discarded after treatment. Phagocytosis activity, oxidative burst and cell viability as well as cytokine release and metabolic parameters of purified GCs were assessed.

RESULTS

Cells were viable throughout the study period and exhibited well-preserved functionality and efficient metabolic activity. Course of lactate dehydrogenase and free hemoglobin concentration yielded no indication of cell impairment. The capability of the cells to secret various cytokines was preserved. Of particular interest is equivalence in performance of the cells on day 1 and day 3, demonstrating the sustained shelf life and performance of the immune cells in the purified GCs.

CONCLUSION

Results demonstrate the suitability of a simplified extracorporeal system. Furthermore, granulocytes remain viable and highly active during a 6-h treatment even after storage for 3 days supporting the treatment of septic patients with this system in advanced clinical trials.

Extrakorporale Behandlungsstrategien der Sepsis

Hintergrund Die Mortalität der Sepsis bleibt auch im 21. Jahrhundert sehr hoch. Verschiedene adjuvante Strategien zur extrakorporalen Zytokinelimination wurden als zusätzliche therapeutische Maßnahmen bei Sepsis und septischem Schock untersucht.

Ziele Zusammenfassung einer Auswahl extrakorporaler Blutreinigungstechniken und der aktuellen Erkenntnisse in der klinischen Anwendung mit besonderem Schwerpunkt auf dem therapeutischen Plasmaaustausch.

Methoden Nicht systematische Literaturrecherche.

Ergebnisse Verschiedene extrakorporale Blutreinigungstechniken mit unterschiedlichen Evidenzniveaus hinsichtlich Zytokinelimination, Verbesserung der Hämodynamik und Verringerung der Mortalität werden derzeit klinisch eingesetzt. Die am ausführlichsten untersuchten Modalitäten umfassen die hochvolumige Hämofiltration/Dialyse mit und ohne High-Cut-off-Filter sowie Hämoadsorptionstechniken (einschließlich CytoSorb- und Polymyxin-B-Filter). Trotz teilweise ermutigender Beobachtungen bezüglich der Entfernung proinflammatorischer Zytokine und verbesserten Hämodynamik zeigten randomisierte Outcome-Studien bislang keinen positiven Einfluss auf das Überleben. Aufgrund der Verwendung von Spenderplasma als Substitutionsflüssigkeit stellt der therapeutische Plasmaaustausch das einzige Verfahren dar, das neben einer reinen Elimination zusätzlich verbrauchte protektive Faktoren ersetzen kann.

Schlussfolgerungen Die Anwendung extrakorporaler Blutreinigungsmethoden kann für Sepsispatienten außerhalb klinischer Studien bisher nicht empfohlen werden, da derzeit keine Beweise für ihre Wirksamkeit vorliegen. Zukünftige Untersuchungen sollten darauf abzielen, das Patientenkollektiv hinsichtlich des klinischen Schweregrads, des Zeitpunkts der Intervention und verschiedener inflammatorischer (Sub-)Phänotypen zu homogenisieren.

The Effects of Hemoadsorption on the Kinetics of Antibacterial and Antifungal Agents

The extracorporeal elimination of a pathogen or damage-associated molecular pattern via blood purification techniques is increasingly being used in patients with septic shock and other clinical conditions characterized by a life-threatening inflammatory response. The removal of these substances can be accomoplished by means of ultrafiltration or hemoadsorption. Independently from the blood putification technique used, they could also affect the clearance of antibacterial and antifungal agents with a potentially significant clinical impact. In our review, we describe the basic principles of ultrafiltration and hemoadsorption, the available devices for this latter and the existing experimental and clinical studies; the final paragraph is dedicated to practical considerations that can help clinicians to consider the clearance of antibiotics and antifungals attributable to these techniques to minimize the risk of a iatrogenic underdosage.

Effects of the timing and intensity of treatment on septic shock patients treated with CytoSorb®: Clinical experience

INTRODUCTION

A group of adult septic shock patients treated with hemoperfusion (HA) with the Cytosorb^® associated with CVVHD were studied to determine (a) the effects of this technique on different clinical variables; and (b) the impact of the pre CytoSorb^® interval and its intensity on the outcome.

METHODS

The catecholamine index (CI) and the pressure-catecholamine Index (PCAI) were used to assess the amount of catecholamine administered at baseline and during the procedure, respectively. The pre-treatment time was calculated since the onset of the septic-shock related hypotension and the initiation of the first session and the intensity was assessed considering either the total volume of blood processed and the duration of the HA.

RESULTS

Overall, 51 patients with septic shock (30 m, 21 f), age 68 years (IQR 59-76) were retrospectively enrolled in the study; 26 were discharged alive form the ICU (S) and 25 died in ICU (NS); in the S group either CI and PCAI decreased significantly but in NS the CI increased and the PCAI remained stable in NS. In S, the time elapsing from the onset of symptoms and the start of Cytosorb^® was shorter than in NS; the duration of the treatment and the volume of blood processed were significantly higher in S than in NS.

CONCLUSIONS

In this group of septic shock patients, the earlier initiation of Cytosorb^®, its longer duration and the higher volume of blood processed were associated with a better survival.