[Plasma exchange in treatment refractory septic shock : Presentation of a therapeutic add-on strategy]

Therapeutic plasma exchange in patients with sepsis: Secondary analysis of a cluster-randomized controlled trial

INTRODUCTION

Sepsis is life-threatening organ dysfunction caused by infection-related inflammatory response. Therapeutic plasma exchange (TPE) can remove inflammatory mediators and benefit patients in different disease settings. However, no solid evidence showed the efficacy and safety of TPE in sepsis.

METHODS

This study was a secondary analysis of a randomized controlled trial. Critically ill patients with sepsis were divided into two groups according to whether treated with TPE. The primary outcome was the delta Sequential Organ Failure Assessment (SOFA) score from days 1 to 7. Secondary outcomes included new-onset organ failure, intensive care unit (ICU)-free and alive days to day 28, and 28-day mortality. Propensity score-matched (PSM) analysis was applied to control confounders. Analysis of covariance (ANCOVA) and logistic regression were used to assess the association between TPE and selected outcomes.

RESULTS

Among the 2772 critically ill patients enrolled in the trial, 742 patients with sepsis were selected and 22 patients received TPE were matched with 22 control patients. No significant difference was found in the delta SOFA score and 28-day mortality between TPE group and control group. The ICU-free and alive days in the TPE group were significantly shorter than the control group.

CONCLUSIONS

TPE may be not associated with improvement of organ failure and mortality in critically ill patients with sepsis and may be associated with a prolonged ICU stay.

Clinical and biochemical endpoints and predictors of response to plasma exchange in septic shock: results from a randomized controlled trial

Background

Recently, a randomized controlled trial (RCT) demonstrated rapid but individually variable hemodynamic improvement with therapeutic plasma exchange (TPE) in patients with septic shock. Prediction of clinical efficacy in specific sepsis treatments is fundamental for individualized sepsis therapy.

Methods

In the original RCT, patients with septic shock of < 24 h duration and norepinephrine (NE) requirement ≥ 0.4 μg/kg/min received standard of care (SOC) or SOC + one single TPE. Here, we report all clinical and biological endpoints of this study. Multivariate mixed-effects modeling of NE reduction was performed to investigate characteristics that could be associated with clinical response to TPE.

Results

A continuous effect of TPE on the reduction in NE doses over the initial 24 h was observed (SOC group: estimated NE dose reduction of 0.005 µg/kg/min per hour; TPE group: 0.018 µg/kg/min per hour, p = 0.004). Similarly, under TPE, serum lactate levels, continuously decreased over the initial 24 h in the TPE group, whereas lactate levels increased under SOC (p = 0.001). A reduction in biomarkers and disease mediators (such as PCT (p = 0.037), vWF:Ag (p < 0.001), Angpt-2 (p = 0.009), sTie-2 (p = 0.005)) along with a repletion of exhausted protective factors (such as AT-III (p = 0.026), Protein C (p = 0.012), ADAMTS-13 (p = 0.008)) could be observed in the TPE but not in the SOC group. In a multivariate mixed effects model, increasing baseline lactate levels led to greater NE dose reduction effects with TPE as opposed to SOC (p = 0.004).

Conclusions

Adjunctive TPE is associated with the removal of injurious mediators and repletion of consumed protective factors altogether leading to preserved hemodynamic stabilization in refractory septic shock. We identified that baseline lactate concentration as a potential response predictor might guide future designing of large RCTs that will further evaluate TPE with regard to hard endpoints.

Trial registration Retrospectively registered 18th January 2020 at clinicaltrials.gov (Identifier: NCT04231994).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04003-2.

Effect of therapeutic plasma exchange on endothelial activation and coagulation-related parameters in septic shock

Background

A dysbalanced coagulation system is part of the pathological host response to infection in sepsis. Activation of pro-coagulant pathways and attenuation of anti-coagulant activity ultimately lead to microvascular stasis and consequent organ failure. No treatment approaches specifically targeting this axis are available. We explored the effects of therapeutic plasma exchange (TPE) on microvascular coagulation dysbalance in septic shock.

Methods

We conducted a prospective single-center study enrolling 31 patients with early septic shock (onset < 12 h) requiring high doses of norepinephrine (NE > 0.4 μg/kg/min). Clinical and biochemical data, including measurement of protein C; a disintegrin and metalloprotease with a thrombospondin type 1 motif, member 13 (ADAMTS13); and von Willebrand factor antigen (vWF:Ag), were obtained before and after TPE against fresh frozen plasma.

Results

Antithrombotic acting proteins such as antithrombin-III (ATIII) and protein C were markedly reduced in septic patients, but their activity increased after TPE (ATIII, 51% (41–61) vs. 63% (48–70), p = 0.029; protein C, 47% (38–60) vs. 62% (54–69), p = 0.029). Median ADAMTS13 activity was increased by TPE from 27 (21–42) % before to 47 (38–62) % after TPE (p < 0.001). In contrast, vWF:Ag was elevated and could be reduced by TPE (353 (206–492) IU/dL vs. 170 (117–232) IU/dL, p < 0.001). Regression analysis yielded a correlation between ADAMTS13 activity and platelet count (p = 0.001, R² = 0.316).

Conclusions

Septic shock was associated with activation of pro-coagulant pathways and simultaneous depletion of anti-coagulant factors. TPE partially attenuated this dysbalance by removing pro- and by replacing anti-coagulant factors.

Trial registration

ClinicalTrials.gov, NCT03065751. Retrospectively registered on 28 February 2017.

Early therapeutic plasma exchange in septic shock: a prospective open-label nonrandomized pilot study focusing on safety, hemodynamics, vascular barrier function, and biologic markers

Background

Given the pathophysiological key role of the host response to an infection rather than the infection per se, an ideal therapeutic strategy would also target this response. This study was designed to demonstrate safety and feasibility of early therapeutic plasma exchange (TPE) in severely ill individuals with septic shock.

Methods

This was a prospective single center, open-label, nonrandomized pilot study enrolling 20 patients with early septic shock (onset < 12 h) requiring high doses of norepinephrine (NE; > 0.4 μg/kg/min) out of 231 screened septic patients. Clinical and biochemical data were obtained before and after TPE. Plasma samples were taken for ex-vivo stimulation of human umbilical vein endothelial cells (HUVECs) to analyze barrier function (immunocytochemistry and transendothelial electrical resistance (TER)). Cytokines were measured by cytometric bead array (CBA) and enzyme-linked immunosorbent assays (ELISAs). An immediate response was defined as > 20% NE reduction from baseline to the end of TPE.

Results

TPE was well tolerated without the occurrence of any adverse events and was associated with a rapid reduction in NE (0.82 (0.61–1.17) vs. 0.56 (0.41–0.78) μg/kg/min, p = 0.002) to maintain mean arterial pressure (MAP) above 65 mmHg. The observed 28-day mortality was 65%. Key proinflammatory cytokines and permeability factors (e.g., interleukin (IL)-6, IL-1b, and angiopoietin-2) were significantly reduced after TPE, while the protective antipermeability factor angiopoietin-1 was not changed. Ex-vivo stimulation of HUVECs with plasma obtained before TPE induced substantial cellular hyperpermeability, which was completely abolished with plasma obtained after TPE.

Conclusions

Inclusion of early septic shock patients with high doses of vasopressors was feasible and TPE was safe. Rapid hemodynamic improvement and favorable changes in the cytokine profile in patients with septic shock were observed. It has yet to be determined whether early TPE also improves outcomes in this patient cohort. An appropriately powered multicenter randomized controlled trial is desirable.

Trial registration

Clinicaltrials.gov, NCT03065751. Retrospectively registered on 28 February 2017.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2220-9) contains supplementary material, which is available to authorized users.