Endotoxin adsorption using polymyxin B immobilized fiber cartridges in severe sepsis patients following cardiac surgery

Selective Polymyxin Hemoperfusion in Complex Therapy of Sepsis in Children after Cardiac Surgery

BACKGROUND

To date, sepsis remains one of the main challenges of intensive care in pediatrics. Newborns with low birth weight and infants with chronic diseases and congenital disorders are particularly at risk. The incidence of infectious complications in pediatric cardiac surgery is known to be approximately 15-30%. The main etiological factor of sepsis is endotoxin.

AIM

To evaluate the efficiency and safety of polymyxin (PMX) B-immobilized column-direct hemoperfusion in complex intensive therapy of sepsis in children after cardiac surgery with cardiopulmonary bypass.

DESIGN

Prospective cohort study.

METHODS

This study enrolled 15 children, aged 9-96 months, with congenital heart diseases and with body weights of 6.2-22.5 kg. The criteria for admission were body weight >6 kg and clinical and laboratory signs of sepsis (microbiological analysis, procalcitonin [PCT] >2 ng/mL, and endotoxin activity assay [ЕАА] >0.6). Intensive care included inotropic and vasopressor support, mechanical ventilation, broad-spectrum antibiotic therapy, and PMX hemoperfusion procedures. Extracorporeal therapy was initiated within 24 h following the sepsis diagnosis. Every patient underwent 2 hemoperfusion sessions with the use of a PMX B-immobilized column; the session duration was 180 min.

RESULTS

We noted improvements in hemodynamic parameters, oxygenation index, and laboratory signs of sepsis, with decreases in the endotoxin concentration according to the EAA, PCT, and presepsin levels. The 28-day survival of the patients in this severely affected group was 80%. Main Conclusion: The inclusion of extracorporeal methods of blood purification, aimed at the selective elimination of circulating endotoxin, in the treatment of sepsis increases the survival rates of children after open heart surgery. Second Conclusion: The obtained results of sepsis therapy with PMX hemoperfusion in children after cardiac surgery enable us to suggest the sufficient safety and efficiency of the procedures in this category of severely affected patients.

Impact of hemoperfusion with polymyxin B added to hemofiltration in patients with endotoxic shock: a case-control study

Background

Septic shock is a leading cause of death in critical patients. In patients with gram-negative septic shock, hemoperfusion with polymyxin B aims to remove endotoxins from plasma. We analyzed the clinical and biological response to hemoperfusion in patients with septic shock and acute kidney injury.

Methods

This prospective case–control study in the medical–surgical intensive care unit of a university hospital included consecutive adults patients with septic shock and suspected gram-negative bacteria infection with elevated plasma endotoxin activity (EAA > 0.6 EU/ml) and acute kidney injury requiring continuous renal replacement therapy (CRRT). At onset of septic shock, half underwent CRRT plus hemoperfusion with polymyxin B for two hours a day during two consecutive days (hemoperfusion group) and half received only CRRT (control group). We measured clinical, physiological, and biological parameters (EAA, C-reactive protein, procalcitonin, and cytokines) daily during the first 5 days.

Results

We included 18 patients (male, 33%; mean age, 67.5; mean SOFA score, 11.3). Abdominal infections predominated (50% had peritonitis). At the beginning of CRRT, RIFLE classification was “failure” for 72% and “injury” for 28%. Baseline characteristics did not differ between groups. Patients in the hemoperfusion group required longer mechanical ventilation (12.4 vs. 9.4 days, p = 0.03) and CRRT (8.5 vs. 6 days, p = 0.01) than in the control group. Noradrenaline doses, lactate, procalcitonin, and C-reactive protein decreased in both groups. At day 5, EAA was significantly lower in the hemoperfusion group (0.58 EU/ml vs. 0.73 EU/ml in controls, p = 0.03). There were no significant differences between groups in other biomarkers or ICU mortality (33.3% in the treatment group vs. 44.4% in the control group, p = 0.5). No adverse effects of hemoperfusion were observed.

Conclusions

Hemoperfusion with polymyxin B added to CRRT resulted in faster decrease in endotoxin levels, but we observed no improvements in clinical, physiological, or biological parameters.

Electronic supplementary material

The online version of this article (10.1186/s13613-018-0465-8) contains supplementary material, which is available to authorized users.

In vitro comparison of the adsorption of inflammatory mediators by blood purification devices

Background

Septic shock, a leading cause of acute kidney injury, induces release of pro-/anti-inflammatory mediators, leading to increased mortality and poor renal recovery. This is the first in vitro study directly comparing three single-use blood purification devices in terms of removing sepsis-associated mediators and endotoxins.

Methods

In vitro hemoperfusion was performed using oXiris^®, CytoSorb^®, and Toraymyxin^®. Heparinized human plasma from healthy volunteers was pre-incubated with pathologic quantities of inflammatory mediators and filtered in a closed-loop circulation model for 2 h. For each device, the removal of 27 inflammatory mediators was measured over time. Endotoxin removal mediated by oXiris and Toraymyxin was assessed using hemoperfusion over 6 h.

Results

Endotoxin (lipopolysaccharide) removal was most rapid with Toraymyxin; mean adsorptive clearance over the first 30 min was ~ 20 ml/min vs ~ 8 ml/min with oXiris (p < 0.05). There was minimal endotoxin removal with CytoSorb (1 ml/min). At 120 min, there was no significant difference between the endotoxin removal rates using oXiris (mean ± standard deviation, 68.0 ± 4.4%) and Toraymyxin (83.4 ± 3.8%); both were significantly higher vs CytoSorb (− 6.3 ± 4.9%; p < 0.05). Total removal with oXiris was 6.9 μg vs 9.7 μg for Toraymyxin, where the total lipopolysaccharide quantity introduced was approximately 15.8 μg. Removal rates of pro-/anti-inflammatory cytokines and other inflammatory mediators were similar between oXiris and CytoSorb and were higher with CytoSorb and oXiris vs Toraymyxin. Granulocyte colony-stimulating factor was only effectively adsorbed by CytoSorb (99.4%). Differences were detected between the adsorption mechanism of the devices; binding to oXiris was mainly ionic, while CytoSorb was hydrophobic. No specific protein adsorption was found qualitatively with Toraymyxin.

Conclusions

Adsorption rate kinetics varied for individual inflammatory mediators using the three blood purification devices. Mechanisms of adsorption differed between the devices. oXiris was the only device tested that showed both endotoxin and cytokine removal. oXiris showed similar endotoxin adsorption to Toraymyxin and similar adsorption to CytoSorb for the removal of other inflammatory mediators. Differences in device removal capacities could enable treatment to be more tailored to patients.

Electronic supplementary material

The online version of this article (10.1186/s40635-018-0177-2) contains supplementary material, which is available to authorized users.

Mechanisms of endothelial activation in sepsis and cell culture models to study the heterogeneous host response

Sepsis is currently viewed as a fundamental disintegration of control functions from intracellular signalling to immunoregulatory and neuroendocrine mechanisms. The immediate threat in sepsis is invasive infection, and the need to activate immune defense mechanisms to clear the pathogen before irreparable damage occurs. In the process of pathogen elimination, however, the systemic host response to infection may cause collateral damage to the endothelium and may lead to the destruction of host tissues.A number of experimental models have been developed to monitor endothelial activation and to study endothelial dysfunction under septic conditions. Here, we review the application of these models to assess the highly variable host response in sepsis and to investigate the efficacy of adsorbent-based extracorporeal therapies. We also highlight the need for efficient diagnostic tools, which are indispensable to select patients who are likely to benefit from distinct adjunctive therapies.

[Methods of Molecular Transfusion in Intensive Care of Critical States in Pediatric Postoperative Cardiac Surgery Patients]

Molecular techniques in transfusion medicine have become popular in the clinical practice of pediatric intensive care units when the patient needs blood purification, more recently, in children in critical condition. Considering the anatomical and physiological characteristics of the child’s body, pronounced severity, and rapid progression of multiple organ disorders, the key problems defining the treatment results are instrument reading, choice and timely initiation of extracorporeal therapy. Today, along with the methods of renal replacement therapy in children albumin dialysis therapy and high-volume plasmapheresis are successfully applied in the treatment of acute liver dysfunction; extracorporeal membrane oxygenation — in the treatment of biventricular cardiac and/or respiratory failure. Selective endotoxin sorption methods (LPS-adsorption) are implemented in the treatment of severe gram-negative sepsis.

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.