Polymyxin B hemoperfusion in endotoxemic septic shock patients without extreme endotoxemia: a post hoc analysis of the EUPHRATES trial

The haemodynamic effects of oXiris haemofilter in septic shock patients requiring renal support: A single-centre experience

Excessive pro-inflammatory and anti-inflammatory cytokines are mediators for haemodynamic alterations, metabolic acidosis, and multi-organ failure in sepsis. Recently, oXiris^® haemofilter (Baxter, IL, USA) has been introduced as a novel haemofilter to mitigate inflammatory response during sepsis-associated acute kidney injury requiring renal replacement therapy. In the present case series, the researchers retrospectively reviewed critically ill patients with septic shock with the use of at least one oXiris haemofilter during continuous renal replacement therapy between June 2015 and December 2017. The timing for oXiris initiation was at the nephrologists' discretion. The impact of oXiris haemofilter was evaluated on mean arterial pressure, vasopressor dosage, Sequential Organ Failure Assessment score, lactate and base excess during 72 h after treatment. Thirty-five patients were enrolled in the study. An improvement of haemodynamic status was found, shown by increased mean arterial pressure by 6.1% (p = 0.35), decreased norepinephrine dose by 45.9% (p = 0.02), inotropic score by 26.4% (p = 0.02) and vasopressor dependency index by 40.5% (p = 0.01). Cardiovascular Sequential Organ Failure Assessment scores significantly decreased over 72 h (p = 0.02). Blood lactate levels and base excess also showed statistically significant improvements. The median filter lifetime was 23 (interquartile range = 14-36) hours. The intensive care unit mortality was 82.9%. Treatment with oXiris was safe and well-tolerated with no device-related adverse events. In conclusion, continuous renal replacement therapy with oXiris haemofilter is safe and may improve haemodynamic parameters in septic patients with severe renal dysfunction. Nonetheless, these findings were drawn from a retrospective analysis without a control group, and therefore cannot be generalised. Randomised controlled trials are warranted to confirm these findings.

Clinical effects of polymyxin B-immobilized fiber column direct hemoperfusion for severe bacterial meningitis: A series of 10 cases

Our results suggest a possible role for Polymyxin B-immobilized fiber column direct hemoperfusion in combination with standard therapy in the rapid improvement of impaired consciousness in patients with severe bacterial meningitis.

Identifying Septic Shock Populations Benefitting From Polymyxin B Hemoperfusion: A Prospective Cohort Study Incorporating a Restricted Cubic Spline Regression Model

INTRODUCTION

Polymyxin B hemoperfusion (PMX-HP) is an adjuvant therapy for sepsis or septic shock that removes circulating endotoxin. However, PMX-HP has seldom achieved expectations in randomized trials targeting nonspecific overall sepsis patients. If used in an optimal population, PMX-HP may be beneficial. This study aimed to identify the optimal population for PMX-HP in patients with septic shock.

METHODS

We used a prospective nationwide cohort targeting consecutive adult patients with severe sepsis (Sepsis-2) in 59 intensive care units in Japan. Associations between PMX-HP therapy and in-hospital mortality were assessed using multivariable Cox proportional hazard regression models. To identify best targets for PMX-HP, we developed a non-linear restricted cubic spline model including two-way interaction term (treatment × Acute Physiology and Chronic Health Evaluation [APACHE] II score/Sequential Organ Failure Assessment [SOFA] score) and three-way interaction term (treatment × age × each score).

RESULTS

The final study cohort comprised 741 sepsis patients (92 received PMX-HP, 625 did not). Cox proportional hazards regression model adjusted for the covariates suggested no association between PMX-HP therapy and improved mortality overall. Effect modification of PMX-HP by APACHE II score was statistically significant (P for interaction = 0.189) but non-significant for SOFA score (P for interaction = 0.413). Three-way interaction analysis revealed suppressed risk hazard in the PMX-HP group versus control group only in septic shock patients with high age and in the most severe subset of both scores, whereas increased risk hazard was observed in those with high age but in the lower severity subset of both scores.

CONCLUSIONS

Our results suggested that although PMX-HP did not reduce in-hospital mortality among overall septic shock patients, it may benefit a limited population with high age and higher disease severity.

Multiscale Biofluidic and Nanobiotechnology Approaches for Treating Sepsis in Extracorporeal Circuits

Infectious diseases and their pandemics periodically attract public interests due to difficulty in treating the patients and the consequent high mortality. Sepsis caused by an imbalanced systemic inflammatory response to infection often leads to organ failure and death. The current therapeutic intervention mainly includes “the sepsis bundles,” antibiotics (antibacterial, antiviral, and antifungal), intravenous fluids for resuscitation, and surgery, which have significantly improved the clinical outcomes in past decades; however, the patients with fulminant sepsis are still in desperate need of alternative therapeutic approaches. One of the potential supportive therapies, extracorporeal blood treatment, has emerged and been developed for improving the current therapeutic efficacy. Here, I overview how the treatment of infectious diseases has been assisted with the extracorporeal adjuvant therapy and the potential utility of various nanobiotechnology and microfluidic approaches for developing new auxiliary therapeutic methods.

Prescription of CRRT: a pathway to optimize therapy

Severe acute kidney injury (AKI), especially when caused or accompanied by sepsis, is associated with prolonged hospitalization, progression to chronic kidney disease (CKD), financial burden, and high mortality rate. Continuous renal replacement therapy (CRRT) is a predominant form of renal replacement therapy (RRT) in the intensive care unit (ICU) due to its accurate volume control, steady acid-base and electrolyte correction, and achievement of hemodynamic stability. This manuscript reviews the different aspects of CRRT prescription in critically ill patients with severe AKI, sepsis, and multiorgan failure in ICU. These include the choice of CRRT versus Intermittent and extended hemodialysis (HD), life of the filter/dialyzer including assessment of filtration fraction, anticoagulation including regional citrate anticoagulation (RCA), prescribed versus delivered CRRT dose, vascular access management, timing of initiation and termination of CRRT, and prescription in AKI/sepsis including adsorptive methods of removing endotoxins and cytokines.

Importance of Endotoxin Clearance in Endotoxemic Septic Shock: An Analysis From the Evaluating Use of PolymyxinB Hemoperfusion in a Randomized Controlled Trial of Adults Treated for Endotoxemic Septic Shock (EUPHRATES) Trial

To investigate the relationship between survival and treatment-related reduction in endotoxin activity for patients in the Evaluating Use of PolymyxinB Hemoperfusion in a Randomized controlled trial of Adults Treated for Endotoxemia and Septic shock trial with baseline endotoxin activity assay greater than or equal to 0.60 to less than 0.90 units.

Design

Post hoc analysis of a multicenter randomized controlled clinical trial.

Setting

Fifty-five tertiary hospitals in North America.

Patients

Patients with septic shock and endotoxin activity assay level greater than or equal to 0.60 to less than 0.90 and multiple organ dysfunction syndrome greater than 9.

Interventions

Two polymyxin B hemoperfusion treatments or Sham.

Measurements and Main Results

One-hundred ninety-four patients were included (88 polymyxin B and 106 Sham). We evaluated the impact of changes in endotoxin activity assay based on comparison to the median reduction from baseline to day 3 and a second method where a target post-treatment endotoxin activity assay level (day 3) was established. The population median reduction in endotoxin activity assay level was 10.4%. In patients with a greater than median reduction, there was trend toward lower mortality with polymyxin B (17.1% vs 33.3%; p = 0.07) and a significant increase in mechanical ventilation-free days (20 vs 13.5; p = 0.04). The pressure adjusted heart rate showed a significant improvement in the polymyxin B group (p = 0.02). For patients who achieved an endotoxin activity assay of less than 0.65 at day 3, the polymyxin B treated group had a trend toward a mortality reduction compared to Sham (16% vs 33%;p = 0.06) and a significant increase in ventilation-free day (20 vs 16; p = 0.05). Kaplan-Meier analysis showed a 17% reduction in mortality with polymyxin B (p = 0.04).

Conclusions

These findings suggest that reducing endotoxin activity assay levels with polymyxin B as measured by comparison to a median reduction or when a treatment target is established, may result in improvements in mortality and organ function outcomes. This article is the first to report endotoxin activity assay measurements in response to polymyxin B use versus Sham in patients with septic shock and elevated endotoxin activity assay. These findings are considered to be hypothesis generating and will need to be prospectively validated.

Prognostic and predictive enrichment in sepsis

Sepsis is a heterogeneous disease state that is both common and consequential in critically ill patients. Unfortunately, the heterogeneity of sepsis at the individual patient level has hindered advances in the field beyond the current therapeutic standards, which consist of supportive care and antibiotics. This complexity has prompted attempts to develop a precision medicine approach, with research aimed towards stratifying patients into more homogeneous cohorts with shared biological features, potentially facilitating the identification of new therapies. Several investigators have successfully utilized leukocyte-derived mRNA and discovery-based approaches to subgroup patients on the basis of biological similarities defined by transcriptomic signatures. A critical next step is to develop a consensus sepsis subclassification system, which includes transcriptomic signatures as well as other biological and clinical data. This goal will require collaboration among various investigative groups, and validation in both existing data sets and prospective studies. Such studies are required to bring precision medicine to the bedside of critically ill patients with sepsis.

The golden hour of polymyxin B hemoperfusion in endotoxic shock: The basis for sequential extracorporeal therapy in sepsis

Endotoxin is recognized as a major trigger of the immune response leading to pro- and anti-inflammatory cytokine release, activation of the coagulation cascade, vasoplegic shock, and multiple organ dysfunction syndrome. A beneficial effect could be achieved through extracorporeal adsorption of circulating endotoxins in the blood as adjunctive treatment for unresponsive endotoxic shock. However, the precise clinical indication for its initiation is widely debated in the literature. Similar to the source control, microbiological cultures and antibiotics administration, endotoxin activity assay evaluation at regular intervals, and the targeted use of PMX-B hemoperfusion could be lifesaving and adequate within the golden hour for the diagnosis and treatment of endotoxic shock.

"Impact of timing of polymyxin B-immobilized fiber column direct hemoperfusion on outcome in patients with septic shock: a single-center observational study"

Aim

The effect of polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) is controversial. The present study investigates whether outcome in septic shock patients is affected by the time until PMX-DHP initiation and the location of the infection site (intra- or extra-abdominal infection (IAI/EAI)].

Methods

This retrospective observational study included patients receiving PMX-DHP for septic shock but excluded those treated after cardiac surgery or cardiac arrest. Based on the median and/or quartile time from catecholamine treatment to PMX-DHP initiation, the patient cohort was divided into four groups and the IAI and EAI groups into two subgroups.

Results

Among the 49 eligible patients, overall 90-day mortality in group 1 (PMX-DHP within 6 h) at 8.3% was significantly lower than in groups 2 (6-9 h; 46.1%), 3 (9-29 h; 58.3%) and 4 (>29 h; 75.0%) (P = 0.021). Multivariate logistic regression analysis showed that the duration from catecholamine treatment to PMX-DHP initiation correlated with 90-day mortality (odds ratio 1.060; 95% confidence interval, 1.004-1.117; P = 0.028). Among the 29 IAI patients, 90-day mortality was significantly lower in the early (within 9 h) than the late group (>9 h) (13.3% versus 64.2%; P = 0.003), but no significant intergroup difference was noted among the 20 EAI patients.

Conclusion

Our results suggest that early PMX-DHP initiation (within 9 h after catecholamine treatment) reduces mortality from septic shock, especially in IAI patients.

Comparative Evaluation of Endotoxin Activity Level and Various Biomarkers for Infection and Outcome of ICU-Admitted Patients

Here, we concurrently measured the endotoxin activity (EA) level and levels of multiple biomarkers in patient blood obtained within 24 h after being admitted into the intensive care unit (ICU) and analyzed whether there were links between these markers and their associations with patient conditions and outcomes. The EA levels highly correlated with disease severity and patient survival, and showed a significant positive association with levels of lactate, procalcitonin, presepsin, and interleukin-6. Notably, the EA level was the marker that most highly correlated with the results of blood culture, and the presepsin level was the marker most highly correlated with the survival outcome at 28 days. Thus, the optimal biomarker should be selected based on whether it will be used to discriminate the presence of an infection or to predict survival.

Acute kidney injury from sepsis: current concepts, epidemiology, pathophysiology, prevention and treatment

Sepsis-associated acute kidney injury (S-AKI) is a frequent complication of the critically ill patient and is associated with unacceptable morbidity and mortality. Prevention of S-AKI is difficult because by the time patients seek medical attention, most have already developed acute kidney injury. Thus, early recognition is crucial to provide supportive treatment and limit further insults. Current diagnostic criteria for acute kidney injury has limited early detection; however, novel biomarkers of kidney stress and damage have been recently validated for risk prediction and early diagnosis of acute kidney injury in the setting of sepsis. Recent evidence shows that microvascular dysfunction, inflammation, and metabolic reprogramming are 3 fundamental mechanisms that may play a role in the development of S-AKI. However, more mechanistic studies are needed to better understand the convoluted pathophysiology of S-AKI and to translate these findings into potential treatment strategies and add to the promising pharmacologic approaches being developed and tested in clinical trials.

The wind changed direction and the big river still flows: from EUPHRATES to TIGRIS

The overall result of the randomized controlled double-blinded trial for polymyxin B-immobilized fiber column on septic shock (EUPHRATES trial) was disappointing. However, post hoc analysis showed benefits for patients with certain Endotoxin Activity Assay (EAA) levels. Thus, the study will be repeated, and the data will be added to the former trial. Using a precision medicine approach, eligibility criteria have been modified in TIGRIS to include patients with MODS score > 9 and EAA levels between 0.60 and 0.89. We are currently feeling the change in the wind as the rivers continue to flow towards PMX therapy for endotoxemic septic shock.

The effect of direct hemoperfusion with polymyxin B immobilized cartridge on meropenem in critically ill patients requiring renal support

PURPOSE

To evaluate the effect of direct hemoperfusion with polymyxin B immobilized cartridge (DHP-PMX) on meropenem pharmacokinetics in critically ill patients with sepsis requiring continuous venovenous hemofiltration (CVVH).

MATERIAL AND METHODS

After intravenous infusion of 1 g meropenem over 3 h repeated every 8 h for at least 3 doses, 2 serial blood and ultrafiltration fluid samples were collected: one over a dose interval of meropenem with DHP-PMX therapy; and the other on the following day over a dose interval of meropenem with no DHP-PMX therapy. Meropenem concentrations were measured by high performance liquid chromatography. Pharmacokinetic parameters of meropenem and extraction ratio of DHP-PMX were calculated.

RESULTS

Mean AUC_0-8 of meropenem on DHP-PMX day was comparable to that of the DHP-PMX free day (285.2 ± 138.2 vs 297.8 ± 130.2 mg ∗ h/L; paired t-test, p = .618). No statistical significance of peak and trough concentrations, volume of distribution, sieving coefficient, or half-life were found. Extraction ratio of DHP-PMX on meropenem was 0 [0-0.03] and clearance by DHP-PMX was 0.04 [0-0.2] L/h which was not considered clinically significant.

CONCLUSIONS

No significant effect of DHP-PMX on meropenem pharmacokinetics was observed among severe sepsis/septic shock patients during CVVH treatment.

TRIAL REGISTRATION

Clinical Trial Registry detail: NCT registry: 02413541 (First registered March 3, 2015, last update October 16, 2017).