Effects of Coupled Plasma Filtration Adsorption on Septic Patients with Multiple Organ Dysfunction Syndrome

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.

Proinflammatory cytokines levels in sepsis and healthy volunteers, and tumor necrosis factor-alpha associated sepsis mortality: A systematic review and meta-analysis

BACKGROUND

Sepsis is a global health challenge associated with significant morbidity and mortality. Detrimental sepsis effects are attributed to excessive inflammation or a "cytokine storm." However, anti-inflammation therapies have failed to lower sepsis mortality. We aim to characterize levels of key inflammatory cytokines in patients with sepsis and compare levels with those in healthy individuals and relate tumor necrosis factor (TNF) α levels to patient characteristics and outcomes.

METHODS

We performed a systematic review and meta-analysis. Medline, Embase, Cochrane Library, and Web of Science Core Collection databases were searched between 1985 and May 2020. Analysis was restricted to studies in English. We included randomized controlled trials (RCTs), controlled trials, cohort studies, case series, and cross-sectional studies that reported mean levels of cytokines in the circulation thought to be relevant for sepsis pathogenesis. We also evaluated concentrations of these cytokines in healthy individuals. The Quality in Prognosis Studies tool was used to assess the methodological quality of included studies. We extracted summary data from published reports. Data analyses were performed using a random-effects model to estimate pooled odds ratios (OR) with 95% confidence intervals for cytokine levels and mortality. This systematic review is registered in PROSPERO (CRD42020179800).

FINDINGS

We identified 3654 records, and 104 studies were included with a total of 3250 participants. The pooled estimated mean TNFα concentration in sepsis patients was 58.4 pg/ml (95% Confidence Interval or CI 39.8-85.8 pg/ml), and in healthy individuals was 5.5 pg/ml (95% CI 3.8-8.0 pg/ml). Pooled estimate means for IL-1β and IFN-γ in sepsis patients were 21.8 pg/ml and 63.3 pg/ml, respectively. Elevated TNFα concentrations associated with increased 28-day sepsis mortality (p = 0.001). In subgroup analyses, we did not detect an association between TNFα levels and sepsis source, sepsis severity, or sequential organ failure assessment (SOFA) score. A TNF-α cutoff level ≥14.7 pg/ml separated sepsis patients from healthy individuals with a sensitivity of 82.6%, a specificity of 91.7%, and a likelihood ratio of 9.9.

INTERPRETATION

Sepsis mean TNFα concentration is increased approximately 10-fold compared to mean concentration in healthy individuals, and TNFα associated with sepsis mortality but not sepsis severity. The concept that elevated cytokines cause sepsis should be revisited in the context of these data.

FUNDING

None.

High dose coupled plasma filtration and adsorption in septic shock patients. Results of the COMPACT-2: a multicentre, adaptive, randomised clinical trial

PURPOSE

This study aimed at evaluating the efficacy and safety of high-dose (> 0.2 L/kg of treated plasma per day) coupled plasma filtration-adsorption (CPFA) in treating patients with septic shock.

METHODS

Multicentre, randomised, adaptive trial, performed in 12 Italian intensive care units (ICUs). Patients aged 14 or more, admitted to the ICU with septic shock, or had developed it during the stay were eligible. The final outcome was mortality at discharge from the last hospital at which the patient received care.

RESULTS

Between May 2015, and October 2017, 115 patients were randomised. The first interim analysis revealed a number of early deaths, prompting an unplanned analysis. Last hospital mortality was non-significantly higher in the CPFA (55.6%) than in the control group (46.2%, p = 0.35). The 90-day survival curves diverged in favour of the controls early after randomisation and remained separated afterwards (p = 0.100). An unplanned analysis showed higher mortality in CPFA compared to controls among patients without severe renal failure (p = 0.025); a dose-response relationship was observed between treated plasma volume and mortality (p = 0.010).

CONCLUSION

The COMPACT-2 trial was stopped due to the possible harmful effect of CPFA in patients with septic shock. The harmful effect, if present, was particularly marked in the early phase of septic shock. Patients not requiring renal replacement therapy seemed most exposed to the possible harm, with evidence of a dose-response effect. Until the mechanisms behind these results are fully understood, the use of CPFA for the treatment of patients with septic shock is not recommended.

Renal Replacement Techniques in Septic Shock

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to an infection; it carries a risk for mortality, considerably exceeding that of a mere infection. Sepsis is the leading cause for acute kidney injury (AKI) and the requirement for renal replacement therapy (RRT) in intensive care unit (ICU) patients. Almost every second critically ill patient with sepsis will develop AKI. In septic shock, the dysregulated host response to infectious pathogens leads to a cytokine storm with uncontrolled production and release of humoral proinflammatory mediators that evoke cellular toxicity and promote the development of organ dysfunction and increased mortality. In addition to treating AKI, RRT techniques can be employed for extracorporeal adsorption of inflammatory mediators using specifically developed adsorption membranes, hemoperfusion sorbent cartridges or columns; these techniques are intended to decrease the level and early deleterious effects of circulating proinflammatory cytokines and endotoxins during the first hours and days of septic shock treatment, in order to improve patient outcomes. Several methods and devices, such as high cut-off membranes, the Oxiris®-AN69 membrane, CytoSorb® and HA380 cytokine hemoadsorption, polymyxin B endotoxin adsorption, and plasmapheresis have been examined in small study series or are under evaluation as ways of improving patient outcomes in septic shock. However, to date, the data on actual outcome benefits have remained controversial, as discussed in this review.

Vasopressor-Sparing Strategies in Patients with Shock: A Scoping-Review and an Evidence-Based Strategy Proposition

Despite the abundant literature on vasopressor therapy, few studies have focused on vasopressor-sparing strategies in patients with shock. We performed a scoping-review of the published studies evaluating vasopressor-sparing strategies by analyzing the results from randomized controlled trials conducted in patients with shock, with a focus on vasopressor doses and/or duration reduction. We analyzed 143 studies, mainly performed in septic shock. Our analysis demonstrated that several pharmacological and non-pharmacological strategies are associated with a decrease in the duration of vasopressor therapy. These strategies are as follows: implementing a weaning strategy, vasopressin use, systemic glucocorticoid administration, beta-blockers, and normothermia. On the contrary, early goal directed therapies, including fluid therapy, oral vasopressors, vitamin C, and renal replacement therapy, are not associated with an increase in vasopressor-free days. Based on these results, we proposed an evidence-based vasopressor management strategy.

An update on membranes and cartridges for extracorporeal blood purification in sepsis and septic shock

PURPOSE OF REVIEW

This review aims to summarize the most recent advances on different membranes and cartridges used for extracorporeal blood purification in critically ill patients with sepsis or septic shock.

RECENT FINDINGS

Despite positive signals from experimental, cases and small clinical studies, blood purification showed no distinct morbidity and mortality benefit in large clinical trials.

SUMMARY

None of the discussed specific membranes or cartridges can currently be recommended as sole adjunctive treatment in sepsis and septic shock. Any available technique should be timely initiated and adapted to the patient's status. Sickest patients seem to benefit more from blood purification. Patient selection is thus of crucial importance and may be optimized by focusing on disease severity and degree of organ failure. Measurement of endotoxin activity and plasma procalcitonin levels can support the selection process but ideal cutoff values need to be defined. Well-designed prospective randomized clinical trials assessing or comparing the various available membranes and cartridges are eagerly awaited.

Effect of High-Volume Hemofiltration in Critically Ill Patients: A Systematic Review and Meta-Analysis

Background

Studies have been carried out to assess the efficacy of high-volume hemofiltration (HVHF) among critically ill patients. However, it is currently unclear whether HVHF is really valuable in critically ill patients.

Material/Methods

Randomized controlled trials evaluating HVHF for critically ill adult patients were included in this analysis. Three databases were searched up to July 27, 2018. The relative risk (RR), mean difference (MD), and 95% confidence intervals (CI) were determined.

Results

Twenty-one randomized controlled trials were included in this analysis. Overall, HVHF was associated with lower mortality compared with control measures (RR=0.88, 95% CI=0.81 to 0.96, P=0.004) in critically ill patients. Sub-analysis revealed HVHF reduced mortality in sepsis and acute respiratory distress syndrome patients, but no similar effect in other diseases. HVHF decreased levels of plasma tumor necrosis factor and interleukin 6. The heart rate of the HVHF group after treatment was slower than the control group, while we found higher mean arterial pressure in the HVHF group, but oxygenation index was not significantly different between the two groups. HVHF had no remarkable influence on acute physiological and chronic health evaluation score (APACHE II score) compared with the control group.

Conclusions

HVHF might be superior to conventional therapy in critically ill patients.

Efficacy of Coupled Plasma Filtration Adsorption in Treating Patients with Severe Intra-Abdominal Infection: A Retrospective Study

Background: Coupled plasma filtration adsorption (CPFA) is an extracorporeal treatment based on plasma filtration associated with an adsorbent cartridge and hemofiltration. CPFA is able to remove inflammatory mediators and it has been used to treat severe sepsis and multiple organ dysfunction. Limited experience exists on the use of CPFA in treating intra-abdominal infection (IAI). Methods: In this study, the efficacy of CPFA in treating patients with severe IAI and liver failure was evaluated in a retrospective analysis of 76 cases. Results: The survival rate of patients treated with CPFA was 82.6%, with effective removal of endotoxin and inflammatory mediators. Conclusion: Our data suggest that CPFA can be safely and effectively used to lower morbidity and mortality rates of patients with severe IAI and liver failure.

A double blind randomized experimental study on the use of IgM-enriched polyclonal immunoglobulins in an animal model of pneumonia developing shock

BACKGROUND

Patients with severe pneumonia often develop septic shock. IgM-enriched immunoglobulins have been proposed as a potential adjuvant therapy for septic shock. While in vitro data are available on the possible mechanisms of action of IgM-enriched immunoglobulins, the results of the in vivo experimental studies are non-univocal and, overall, unconvincing. We designed this double blinded randomized controlled study to test whether IgM-enriched immunoglobulins administered as rescue treatment in a pneumonia model developing shock, could either limit lung damage and/or contain systemic inflammatory response.

METHODS

Thirty-eight Sprague Dawley rats were ventilated with injurious ventilation for 30min to prime the lung. The rats were subsequently randomized to received intratracheal instillation of either lipopolysaccharide (LPS) (12mg/kg) or placebo followed by 3.5h of protective mechanical ventilation. IgM-enriched immunoglobulins at 25mg/h (0.5mL/h) or saline were intravenously administered in the last hour of mechanical ventilation. During the experiment, gas exchange and hemodynamic measurements were recorded. Thereafter, the animals were sacrificed, and blood and organs were stored for cytokines measurements.

RESULTS

Despite similar lung and hemodynamic findings, the administration of IgM-enriched immunoglobulins compared to placebo significantly modulates the inflammatory response by increasing IL-10 levels in the bloodstream and by decreasing TNF-α in bronchoalveolar lavage (BAL) fluid. Furthermore, in vitro data suggest that IgM-enriched immunoglobulins induce monocytes production of IL-10 after LPS stimulation.

CONCLUSIONS

In an in vivo model of pneumonia developing shock, IgM-enriched immunoglobulins administered as rescue treatment enhance the anti-inflammatory response by increasing blood levels of IL-10 and reducing TNF-α in BAL fluid.

Plasmapheresis and other extracorporeal filtration techniques in critical patients

Plasmapheresis is an extracorporeal technique that eliminates macromolecules involved in pathological processes from plasma. A review is made of the technical aspects, main indications in critical care and potential complications of plasmapheresis, as well as of other extracorporeal filtration techniques such as endotoxin-removal columns and other devices designed to eliminate cytokines or modulate the inflammatory immune response in critical patients.

Coupled plasma filtration adsorption improves hemodynamics in septic shock

PURPOSE

Septic shock involves a dysregulation of the immune response to an infection. This may lead to hemodynamic dysfunction and multiple-organ failure. The main aim of this study was to evaluate the effect of coupled plasma filtration adsorption (CPFA) on the hemodynamic profile in patients with septic shock.

MATERIALS AND METHODS

We retrospectively analyzed data from 21 adult patients admitted to the intensive care unit with a diagnosis of septic shock, comparing data between pre-CPFA and post-CPFA treatment. They received a maximum of 5 cycles of treatment.

RESULTS

Coupled plasma filtration adsorption treatment was associated with a significant increase of mean arterial pressure (P < .001), reduction of the vasoactive/inotropic requirement (P = .007), and renal improvement. In patients with leukocytosis or leucopenia, the leukocyte count was restored to a reference range of values.

CONCLUSION

Treatment with CPFA improves hemodynamic parameters in septic shock patients, ameliorating organ failure.

Coupled plasma haemofiltration filtration in severe sepsis: systematic review and meta-analysis

INTRODUCTION

Coupled plasma filtration and adsorption (CPFA) has been used in the treatment of severe sepsis with the intention of removing the proinflammatory and anti-inflammatory mediators from the systemic circulation. It is believed that this interrupts and moderates the septic cascade, but there is uncertainty about the benefits of this therapy.

METHODS

A systematic review and meta-analysis were performed to estimate the effects of CPFA on mortality in severe sepsis. The Cochrane CENTRAL Register of Controlled Trials, CINAHL, EMBASE, MEDLINE-EBSCO-Host, MEDLINE and ProQuest, were searched from 1997 to 2013. Randomised controlled trials, prospective cohort studies and retrospective cohort studies were included using the Centre for Reviews and Dissemination (CRD) framework. Data were abstracted using standard pro forma, and studies independently reviewed by two authors to confirm inclusion criteria. Quality of studies and risk of bias were assessed using the Grading of Recommendations, Assessment, Development and Evaluation Working Group (GRADE) and Critical Appraisal Skills (CASP) criteria, respectively. Meta-analysis was performed using Review Manager (RevMan V.5.1) software. The primary outcome was 28-day mortality. Secondary outcomes were mediator adsorption (picograms/mL), mean arterial BP (mm Hg) and oxygenation ratio.

RESULTS

17 studies met the inclusion criteria (n=441 patients, 242 CPFA). 14 studies reported the primary outcome of 28-day mortality. There were 88 deaths in CPFA patients versus 118 in those receiving haemofiltration: OR 0.34 (95% CI 0.24 to 0.13). Point estimates of effect on the secondary outcomes of mean arterial pressure and oxygen ratio favoured CPFA. Studies were small and heterogenous.

CONCLUSIONS

Evidence for CPFA in severe sepsis is sparse, of poor quality and further research is required, however, this meta-analysis noted improvements in survival rates of those patients treated with CPFA.

A pilot study of selective lipopolysaccharide adsorption and coupled plasma filtration and adsorption in adult patients with severe sepsis

AIM

To evaluate the safety and effectiveness of combined extracorporeal therapy in patients with severe sepsis after cardiac surgery.

MATERIALS AND METHODS

Twenty patients received combined extracorporeal therapy (LPS-adsorption with Toraymyxin columns + CPFA). The inclusion criteria were clinical signs of severe sepsis, EAA = 0.6, and PCT >2 ng/ml. 20 comparable patients in the control group received only standard therapy.

RESULTS

Each patient in the study group received 2 daily treatments of combined extracorporeal therapy. In contrast to controls, we noted an increase in the values of MAP from 73 to 82 mm Hg, (p < 0.001) and the mean oxygenation index (from 180 to 246, p < 0.001), decrease of EAA from 0.77 to 0.55, p < 0.001, and PCT (from 6.23 to 2.83 ng/ml, p < 0.001). The 28-day survival rate was 65 and 35% in the study and control groups respectively, p = 0.11.

CONCLUSION

The combined use of LPS-adsorption and CPFA in a single circuit with standard therapy is a safe and possibly effective adjunctive method for treating severe sepsis.

Alteco endotoxin hemoadsorption in Gram-negative septic shock patients

Background and Aims:

Severe sepsis and septic shock are common causes of mortality and morbidity in an intensive care unit setting. Endotoxin, derived from the outer membranes of Gram-negative bacteria, is considered a major factor in the pathogenesis of sepsis. This study investigated the effect of Alteco endotoxin hemoadsorption device on Gram-negative septic shock patients.

Materials and Methods:

An open, controlled, prospective, randomized, single-center trial was conducted between February 2010 and June 2012. Patients with septic shock due to intra-abdominal sepsis were randomized to either conventional therapy (n = 8) or conventional therapy plus two 2-hourly sessions of Alteco endotoxin hemoadsorption (n = 7). Primary endpoint was the Sequential Organ Failure Assessment (SOFA) score changes from 0 to 72 h. Secondary end points included vasopressor requirement, PaO₂/FiO₂ ratio (PFR), length of stay (LOS), and 28-day mortality.

Results:

This study was terminated early as interim analysis showed a low probability of significant findings. No significant difference was noted between the two groups with respect to change in SOFA score, vasopressor score, PFR, LOS, and 28-day mortality. Side-effect was minimal.

Conclusions:

We could not identify any clinical benefit on the addition of Alteco endotoxin hemoadsorption to conventional therapy in patients who suffered from intra-abdominal sepsis with shock. The side effect profile of this novel device was acceptable.

HMGB1 in health and disease

Complex genetic and physiological variations as well as environmental factors that drive emergence of chromosomal instability, development of unscheduled cell death, skewed differentiation, and altered metabolism are central to the pathogenesis of human diseases and disorders. Understanding the molecular bases for these processes is important for the development of new diagnostic biomarkers, and for identifying new therapeutic targets. In 1973, a group of non-histone nuclear proteins with high electrophoretic mobility was discovered and termed high-mobility group (HMG) proteins. The HMG proteins include three superfamilies termed HMGB, HMGN, and HMGA. High-mobility group box 1 (HMGB1), the most abundant and well-studied HMG protein, senses and coordinates the cellular stress response and plays a critical role not only inside of the cell as a DNA chaperone, chromosome guardian, autophagy sustainer, and protector from apoptotic cell death, but also outside the cell as the prototypic damage associated molecular pattern molecule (DAMP). This DAMP, in conjunction with other factors, thus has cytokine, chemokine, and growth factor activity, orchestrating the inflammatory and immune response. All of these characteristics make HMGB1 a critical molecular target in multiple human diseases including infectious diseases, ischemia, immune disorders, neurodegenerative diseases, metabolic disorders, and cancer. Indeed, a number of emergent strategies have been used to inhibit HMGB1 expression, release, and activity in vitro and in vivo. These include antibodies, peptide inhibitors, RNAi, anti-coagulants, endogenous hormones, various chemical compounds, HMGB1-receptor and signaling pathway inhibition, artificial DNAs, physical strategies including vagus nerve stimulation and other surgical approaches. Future work further investigating the details of HMGB1 localization, structure, post-translational modification, and identification of additional partners will undoubtedly uncover additional secrets regarding HMGB1's multiple functions.

Coupled Plasma Filtration and Adsorption (CPFA): A Single Center Experience

Background

Coupled plasma filtration adsorption (CPFA) is a novel extracorporeal blood purification therapy for sepsis which adsorbs both proinflammatory and anti-inflammatory mediators from filtered plasma, thereby achieving early haemodynamic stability and a reduction in inotropic support requirement.

Objectives

The main objective was to review our centers' experience with CPFA in septic patients.

Patients and Methods

A retrospective chart review of all septic patients who received CPFA was performed. All patients were initially treated according to the ‘surviving sepsis care bundle’ with fluid resuscitation, antibiotics, and inotropes as required. CPFA was started as soon as possible after a nephrologists’ assessment.

Results

Twenty five patients with sepsis received CPFA (15 M, 10 F, mean age 49.60 ± 18.97 years). Comorbidities included hypertension (n = 10, 40%), diabetes mellitus (n = 6, 24%), ischemic heart disease (n = 6, 24%), and an immunosuppressed state (n = 10, 40%). All patients received one cycle of CPFA with median duration of 5 (1-10) hours. CPFA was well tolerated but we encountered technical problems, especially filter clotting as CPFA was performed heparin free. 14 (56%) patients died within 28 days of treatment. CRP correlated with PCT (P = 0.040) and had an inverse trend with albumin (P = 0.066). Serum albumin was a strong predictor of mortality.

Conclusions

The high prevalence of fungaemia and mortality could be attributed to many patients on chronic immunosuppressive therapy. Nonetheless, CPFA albeit expensive, does add to our armamentarium of extracorporeal treatment for severe sepsis. Regional citrate anticoagulation with CPFA may overcome problems with filter clotting.

The selective therapeutic apheresis procedures

Selective apheresis procedures have been developed to target specific molecules, antibodies, or cellular elements in a variety of diseases. The advantage of the selective apheresis procedures over conventional therapeutic plasmapheresis is preservation of other essential plasma components such as albumin, immunoglobulins, and clotting factors. These procedures are more commonly employed in Europe and Japan, and few are available in the USA. Apheresis procedures discussed in this review include the various technologies available for low-density lipoprotein (LDL) apheresis, double filtration plasmapheresis (DFPP), cryofiltration, immunoadsorption procedures, adsorption resins that process plasma, extracorporeal photopheresis, and leukocyte apheresis.

Newly designed CRRT membranes for sepsis and SIRS--a pragmatic approach for bedside intensivists summarizing the more recent advances: a systematic structured review

In recent years, after all the attention has been focused on the dose for continuous renal replacement therapy (CRRT) in sepsis and systemic inflammation response syndrome (SIRS), the relatively negative results of all those studies did urge our expectations on new approaches regarding CRRT in sepsis and SIRS. So far, after the failure of the major randomized studies on dose, attention is now drawn to new membranes that could better eliminate massive amounts of unbound mediators in wider spectrum and also in greater magnitude Nevertheless, for septic acute kidney injury, the recommended dose will remain 35 ml/kg/h until the IVOIRE (hIgh VOlume in Intensive Care) study will be published. In this new armamentarium, we have distinguished the first tools that can still be called membranes ranging from AN69 Surface Treated (ST), SEPTEX, polymethylmetacrylate, to Oxiris that can still run with a CRRT device. Polymyxin B is still a kind of membrane although it has a larger surface, but it can run in a hemoperfusion system and is also much more selective. Adsorptive columns and sorbents are not anymore membranes but are seen as cartridges as the surface is extremely huge when compared with that of membranes (more than 500 m). They can still run in a hemoperfusion device. At the very end, we do have apheresis or selective plasma exchange (also very close to sorbents and columns) but we have very few data up to now regarding sepsis. Regarding spectrum, CytoSorb seems to be very promising although it is not able to capture endotoxin and IL-10. Oxiris is also promising as it can capture endotoxin and cytokines. AN69 ST is very powerful to capture numerous cytokines and especially high-mobility group box 1 protein (a very upstream cytokine). Polymethylmetacrylate has also the power to capture endotoxin and numerous other cytokines probably with a larger magnitude than Oxiris although this is not proven. Lastly, high-porosity membranes (Septex) may play a role especially when used in continuous venovenous hemodialysis mode. At the end, if we look for a more enlarged spectrum and a higher magnitude, CytoSorb might be seen as the most promising although not having the ability to fix endotoxin. Future studies will tell us which membrane or sorbent will be most useful in the adjunctive treatment for sepsis.