Plasmapheresis combined with continuous venovenous hemofiltration in surgical patients with sepsis

Influence of therapeutic plasma exchange treatment on short-term mortality of critically ill adult patients with sepsis-induced organ dysfunction: a systematic review and meta-analysis

INTRODUCTION

The impact of therapeutic plasma exchange (TPE) on short-term mortality in adult patients with sepsis-induced organ dysfunction remains uncertain. The objective of the study is to assess the effect of adjunct TPE in this setting through a comprehensive literature review.

METHODS

The National Library of Medicine's Medline, Ovid (Embase), the Cochrane Library database and clinicaltrial.gov from January 01, 1966, until October 01, 2022, were searched for terms: therapeutic plasma exchange, plasmapheresis, sepsis, and septic shock. We reviewed, selected and extracted data from relevant randomized clinical trials (RCTs) and matched cohort studies (MCSs) comparing short-term mortality in critically ill adult septic patients treated with standard therapy versus those receiving adjunct TPE. Risk of bias was assessed in the RCTs using Cochrane Collaboration tool and in MCSs using ROBINS-I tool. Summary statistics, risk ratios (RRs), and confidence intervals (CIs) were calculated using random effects model.

RESULTS

This systematic review included 937 adult critically ill septic patients from five RCTs (n = 367) and fifteen MCSs (n = 570). Of these total, 543 received treatment with TPE in addition to standard care. The meta-analysis includes all five RCTs and only six MCSs (n = 627). The adjunct TPE treatment (n = 300) showed a significant reduction in short-term mortality (RR 0.59, 95% CI 0.47-0.74, I2 3%) compared to standard therapy alone (n = 327). The systematic review of all 20 trials revealed that adding TPE to the standard therapy of critically ill septic patients resulted in faster clinical and/or laboratory recovery.

CONCLUSIONS

Our comprehensive and up-to-date review demonstrates that adjunct TPE may provide potential survival benefits when compared to standard care for critically ill adult patients with sepsis-induced organ dysfunction. While results of this meta-analysis are encouraging, large well-designed randomized trials are required to identify the optimal patient population and TPE procedure characteristics prior to widespread adoption into practice.

Sequential Blood Purification for Pediatric Fatal Toxic Epidermal Necrolysis: A Case Series

BACKGROUND

Extracorporeal therapy that included therapeutic plasma exchange (TPE) or continuous hemofiltration (CHF) for toxic epidermal necrolysis (TEN) syndrome was used in small number of patients. We aimed to describe the sequential mode of combined application of CHF and TPE in 3 TEN patients with multiple organ dysfunction (MODS) in pediatric intensive care unit.

METHODS

Three patients with fatal TEN received sequential CHF and TPE due to unsatisfactorily conventional treatments. CHF was initiated and performed on a daily basis with 35-50 mL/kg.h replacement fluid at the rate of 3-5 mL/kg.min blood flow. CHF was temporarily interrupted for TPE, which was performed with exchange 1-1.5-fold of one body calculated plasma volume in each section.

RESULTS

All 3 fatal TEN (with >30% involvement of body surface and MODS) following unsuccessful treatment with corticosteroids and intravenous immunoglobulin. Antibiotics were suspected in the TEN-triggered drugs. The range number of TPE sessions was 3-5 and the duration of CHF was from 120 h to 202 h. After initiation of TPE and CHF, blistering with extensive epidermal necrosis halted and the skin re-epithelialized within 2 weeks. Serum C-reactive protein, procalcitonin, tumor necrosis factor-α , and interlukin-6 decreased and percentage of natural killer cells increased in surviving children. Two patients survived to discharge and one case died due to nosocomial infection with multidrug-resistant Acinetobacter baumannii.

CONCLUSION

After sequential TPE and CHF, skin lesions and inflammatory response improved in TEN. Our result indicates extracorporeal therapy could be used as an alternative modality for fatal pediatric TEN.

Efficacy of 4-hour rescue therapeutic plasma exchange in severe septic shock patients

BACKGROUND

Early intervention for septic shock is crucial to reduce mortality and improve outcome. There is still a great debate over the exact time of therapeutic plasma exchange (TPE) administration in septic shock patients. This study aims to investigate the effect of early initiation (within 4 hours) of TPE in severe septic shock on hemodynamics & outcome.

METHODS

We conducted a prospective, before-after case series study on 16 septic shock patients requiring high doses of vasopressors admitted in two ICUs from Cairo, Egypt. All of our patients received TPE within 4 hours of ICU admission. The fresh frozen plasma exchange volume = 1.5 × plasma volume.

RESULTS

In the 16 patients included in the study, mean arterial pressure was significantly improved after the initial TPE (p < 0.002) and norepinephrine dose which significantly reduced post TPE (p < 0.001). In addition, norepinephrine dose to mean arterial pressure significantly improved (p < 0.001). There was reduction of a net 6 hours fluid balances following the first TPE were observed in all the patients (p < 0.03) by a mean of 757 ml. Systemic vascular resistance index was markedly improved post-TPE along with statistically improved cardiac index (p < 0.01). Stroke volume variance was also significantly decreased after the TPE sessions (p < 0.01). C-reactive protein significantly improved after TPE (P < 0.01).

CONCLUSION

Early initiation of TPE in severe septic shock patients might improve hemodynamic measures.

Sepsis: mechanisms of bacterial injury to the patient

In bacteremia the majority of bacterial species are killed by oxidation on the surface of erythrocytes and digested by local phagocytes in the liver and the spleen. Sepsis-causing bacteria overcome this mechanism of human innate immunity by versatile respiration, production of antioxidant enzymes, hemolysins, exo- and endotoxins, exopolymers and other factors that suppress host defense and provide bacterial survival. Entering the bloodstream in different forms (planktonic, encapsulated, L-form, biofilm fragments), they cause different types of sepsis (fulminant, acute, subacute, chronic, etc.). Sepsis treatment includes antibacterial therapy, support of host vital functions and restore of homeostasis. A bacterium killing is only one of numerous aspects of antibacterial therapy. The latter should inhibit the production of bacterial antioxidant enzymes and hemolysins, neutralize bacterial toxins, modulate bacterial respiration, increase host tolerance to bacterial products, facilitate host bactericidal mechanism and disperse bacterial capsule and biofilm.

The Influence of HES on the Filtration Properties of Capillary Membrane Plasmaseparation

Plasmaseparation is a treatment under discussion for critically ill patients, especially in sepsis and multiorgan failure. These patients receive a variety of different fluid substitutes, including hydroxyethylstarch (HES). HES is known to influence rheological properties, but nothing is known about the possible interactions between HES and the plamaseparation procedure. We used an in vitro plasmaseparation circuit with heparinized porcine blood. Before priming the system, 2 liters of blood were supplemented by adding 100 ml of either NaCl 0.9% or HES (n=6 in each group). We monitored the transmembrane (TMP) and the filtration pressure (PF) and measured free plasma hemoglobin (free Hb) and platelet counts before and after the two hours plasmaseparation procedure. The final transmembrane pressure was significantly higher with HES substitution. In the HES group we found negative filtration pressures from the very beginning with a significant further decrease toward the end of the experiments. A significant increase in free Hb and decrease in platelet counts were noted only in the HES group. Volume substitution with HES leads to impaired filtration properties and deteriorated hemocompatibility in in vitro plasmaseparation. Further studies have yet to evaluate whether or not the effects described also occur under clinical conditions.

Sepsis and septic shock: Pathogenesis and treatment perspectives

The majority of bacteremias do not develop to sepsis: bacteria are cleared from the bloodstream. Oxygen released from erythrocytes and humoral immunity kill bacteria in the bloodstream. Sepsis develops if bacteria are resistant to oxidation and proliferate in erythrocytes. Bacteria provoke oxygen release from erythrocytes to arterial blood. Abundant release of oxygen to the plasma triggers a cascade of events that cause: 1. oxygen delivery failure to cells; 2. oxidation of plasma components that impairs humoral regulation and inactivates immune complexes; 3. disseminated intravascular coagulation and multiple organs' failure. Bacterial reservoir inside erythrocytes provides the long-term survival of bacteria and is the cause of ineffectiveness of antibiotics and host immune reactions. Treatment perspectives that include different aspects of sepsis development are discussed.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice-Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Seventh Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.

Use of Cellular and Plasma Apheresis in the Critically Ill Patient: Part II: Clinical Indications and Applications

Apheresis is the process of separating the blood and removing or manipulating a cellular or plasma component for therapeutic benefit. Such procedures may be indicated in the critical care setting as primary or adjunctive therapy for certain hematologic, neurologic, renal, and autoimmune/rheumatologic disorders. In part I of this series, the technical aspects of apheresis were described and the physiologic rationale and clinical considerations were discussed. This review highlights the pathophysiologic basis, specific clinical indications, and treatment parameters for disorders that more commonly require management in the intensive care unit. The choice of plasma or cellular apheresis in these cases is guided by wellaccepted, evidence-based clinical treatment guidelines. For some disorders, such as liver failure, severe sepsis, and multiple-organ dysfunction syndrome, apheresis treatment approaches remain experimental. Ongoing studies are investigating the potential utility of conventional plasma exchange, ex vivo plasma manipulation, and newer technologies for these and other disorders in severely ill patients.

Use of Cellular and Plasma Apheresis in the Critically Ill Patient: Part 1: Technical and Physiological Considerations

Apheresis is the process of separating the blood and removing or manipulating a cellular or plasma component for therapeutic benefit. An apheresis procedure, or series of procedures, may be indicated in the critical care setting as primary or adjunctive therapy for certain hematologic, neurologic, renal, and autoimmune/ rheumatologic disorders. Optimal management of severely ill patients undergoing apheresis requires a working knowledge of the technical, methodological, and therapeutic considerations. These considerations include instrument hardware and separation methods, vascular access requirements, hemodynamic and hemostatic effects of the procedures, exposure to anticoagulants and homologous blood products, physiological variables affecting blood/plasma processing efficiency, and therapeutic endpoints for specific indications. Part 1 of this review will discuss each of those technological considerations and the basic physiological principles that guide this form of therapy. Part 2 of this series will deal with the clinical indications and applications for specific disorders that are most likely to affect patients in the intensive care unit.

Obesity and Sepsis

Obesity has reached epidemic proportions over the last few decades. Obesity is associated with increased morbidity and mortality in hypertension, cardiovascular diseases, stroke, and cancer and is feared to decrease overall life expectancy over the next few decades. There is a growing body of evidence suggesting that obesity is a chronic inflammatory disease. Obesity is becoming a cause of concern in critically ill patients as well. Sepsis is the number one cause of morbidity and mortality in noncoronary artery disease critical care units all over the world and is associated with a high cost of care. An increase in morbidity in obese septic patients compared with lean people is a cause of growing concern. Laboratory evidence suggests that there is exaggeration in the inflammatory and prothrombogenic phenotype assumed by obese compared with lean septic animals. The exact mechanisms underlying this phenomenon are unknown. This article reviews some of the pathophysiological processes responsible for the underlying inflammation in obesity and sepsis and reviews the literature for the association of the two.

Therapeutic plasma exchange may improve hemodynamics and organ failure among children with sepsis-induced multiple organ dysfunction syndrome receiving extracorporeal life support

OBJECTIVE

To determine the effect of therapeutic plasma exchange on hemodynamics, organ failure, and survival in children with multiple organ dysfunction syndrome due to sepsis requiring extracorporeal life support.

DESIGN

A retrospective analysis.

SETTING

A PICU in an academic children's hospital.

PATIENTS

Fourteen consecutive children with sepsis and multiple organ dysfunction syndrome who received therapeutic plasma exchange while on extracorporeal life support from 2005 to 2013.

INTERVENTIONS

Median of three cycles of therapeutic plasma exchange with median of 1.0 times the estimated plasma volume per exchange.

MEASUREMENTS AND MAIN RESULTS

Organ Failure Index and Vasoactive-Inotropic Score were measured before and after therapeutic plasma exchange use. PICU survival in our cohort was 71.4%. Organ Failure Index decreased in patients following therapeutic plasma exchange (mean ± SD: pre, 4.1 ± 0.7 vs post, 2.9 ± 0.9; p = 0.0004). Patients showed improved Vasoactive-Inotropic Score following therapeutic plasma exchange (median [25th-75th]: pre, 24.5 [13.0-69.8] vs post, 5.0 [1.5-7.0]; p = 0.0002). Among all patients, the change in Organ Failure Index was greater for early therapeutic plasma exchange use than late use (early, -1.7 ± 1.2 vs late, -0.9 ± 0.6; p = 0.14), similar to the change in Vasoactive-Inotropic Score (early, -67.5 [28.0-171.2] vs late, -12.0 [7.2-18.5]; p = 0.02). Among survivors, the change in Organ Failure Index was greater among early therapeutic plasma exchange use than late use (early, -2.3 ± 1.0 vs late, -0.8 ± 0.8; p = 0.03), as was the change in Vasoactive-Inotropic Score (early, -42.0 [16.0-76.3] vs late, -12.0 [5.3-29.0]; p = 0.17). The mean duration of extracorporeal life support after therapeutic plasma exchange according to timing of therapeutic plasma exchange was not statistically different among all patients or among survivors.

CONCLUSIONS

The use of therapeutic plasma exchange in children on extracorporeal life support with sepsis-induced multiple organ dysfunction syndrome is associated with organ failure recovery and improved hemodynamic status. Initiating therapeutic plasma exchange early in the hospital course was associated with greater improvement in organ dysfunction and decreased requirement for vasoactive and/or inotropic agents.

The efficacy and safety of plasma exchange in patients with sepsis and septic shock: a systematic review and meta-analysis

Introduction

Sepsis and septic shock are leading causes of intensive care unit (ICU) mortality. They are characterized by excessive inflammation, upregulation of procoagulant proteins and depletion of natural anticoagulants. Plasma exchange has the potential to improve survival in sepsis by removing inflammatory cytokines and restoring deficient plasma proteins. The objective of this study is to evaluate the efficacy and safety of plasma exchange in patients with sepsis.

Methods

We searched MEDLINE, EMBASE, CENTRAL, Scopus, reference lists of relevant articles, and grey literature for relevant citations. We included randomized controlled trials comparing plasma exchange or plasma filtration with usual care in critically ill patients with sepsis or septic shock. Two reviewers independently identified trials, extracted trial-level data and performed risk of bias assessments using the Cochrane Risk of Bias tool. The primary outcome was all-cause mortality reported at longest follow-up. Meta-analysis was performed using a random-effects model.

Results

Of 1,957 records identified, we included four unique trials enrolling a total of 194 patients (one enrolling adults only, two enrolling children only, one enrolling adults and children). The mean age of adult patients ranged from 38 to 53 years (n = 128) and the mean age of children ranged from 0.9 to 18 years (n = 66). All trials were at unclear to high risk of bias. The use of plasma exchange was not associated with a significant reduction in all-cause mortality (risk ratio (RR) 0.83, 95% confidence interval (CI) 0.45 to 1.52, I² 60%). In adults, plasma exchange was associated with reduced mortality (RR 0.63, 95% CI 0.42 to 0.96; I² 0%), but was not in children (RR 0.96, 95% CI 0.28 to 3.38; I² 60%). None of the trials reported ICU or hospital lengths of stay. Only one trial reported adverse events associated with plasma exchange including six episodes of hypotension and one allergic reaction to fresh frozen plasma.

Conclusions

Insufficient evidence exists to recommend plasma exchange as an adjunctive therapy for patients with sepsis or septic shock. Rigorous randomized controlled trials evaluating clinically relevant patient-centered outcomes are required to evaluate the impact of plasma exchange in this condition.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0699-2) contains supplementary material, which is available to authorized users.

Evaluation of plasma exchange and continuous veno-venous hemofiltration for the treatment of severe avian influenza A (H7N9): a cohort study

Avian influenza A (H7N9) is a severe disease with high mortality. Hypercytokinemia is thought to play an important role in the pathogenesis. This study was to investigate the efficiency of plasma exchange (PE) + continuous veno-venous hemofiltration (CVVH) on the removal of inflammatory mediators and their benefits in the management of fluid overload and metabolic disturbance. In total, 40 H7N9-infected patients were admitted to our hospital. Sixteen critically ill H7N9-infected patients received combination of PE and CVVH. Data from these 16 patients were collected and analyzed. The effects of PE + CVVH on plasma cytokine/chemokine levels and clinical outcomes were examined. H7N9-infected patients had increased plasma levels compared to healthy controls. After 3 h of PE + CVVH treatment, the cytokine/chemokine levels descended remarkably to lower levels and were maintained thereafter. PE + CVVH also benefited the management of fluid, cardiovascular dysfunction and metabolic disturbance. Of the 16 critically ill patients who received PE + CVVH, 10 patients survived. PE + CVVH decreased the plasma cytokine/chemokine levels significantly. PE + CVVH were also beneficial to the management of severe avian influenza A (H7N9).

Therapeutic plasma exchange as rescue therapy in severe sepsis and septic shock: retrospective observational single-centre study of 23 patients

BACKGROUND

Several case series and small randomized controlled trials suggest that therapeutic plasma exchange (TPE) improves coagulation, hemodynamics and possibly survival in severe sepsis. However, the exact role of TPE in modern sepsis therapy remains unclear.

METHODS

We performed a retrospective observational single-centre study on the use of TPE as rescue therapy in 23 consecutive patients with severe sepsis or septic shock from 2005 to 2012. Main surrogate markers of multiple organ failure (MOF) before, during and after TPE as well as survival rates are reported.

RESULTS

At baseline, mean SOFA score was 13 (standard deviation [SD] 4) and median number of failed organ-systems was 5 (interquartile range [IQR] 4-5). TPEs were performed 3 days (IQR 2-10) after symptom onset and 1 day (IQR 0-8) after ICU admission. The median total exchange volume was 3750 ml (IQR 2500-6000), which corresponded to a mean of 1.5 times (SD 0.9) the individual plasma volume. Fresh frozen plasma was used in all but one treatments as replacement fluid. Net fluid balance decreased significantly within 12 hrs following the first TPE procedure by a median of 720 mL (p = 0.002), irrespective of outcome. Reductions of norepinephrine dose and improvement in cardiac index were observed in individual survivors, but this was not significant for the overall cohort (p = 0.574). Platelet counts decreased irrespective of outcome between days 0 and 2 (p < 0.003), and increased thereafter in many survivors. There was a non-significant trend towards younger age and higher procalcitonin levels among survivors. Nine out of 23 TPE treated patients (39%) survived until ICU discharge (among them 3 patients with baseline SOFA scores of 15, 17, and 20).

CONCLUSIONS

Our data suggest that some patients with severe sepsis and septic shock may experience hemodynamic stabilisation by early TPE therapy.

Therapeutic plasma exchange in an intensive care unit (ICU): a 10-year, single-center experience

Therapeutic plasma exchange (TPE) is a blood purification method that effectively allows for the removal of waste substances by separating out plasma from other components of blood and the removed plasma is replaced with solutions such as albumin and/or plasma, or crystalloid/colloid solutions. Plasma exchange therapies are becoming increasingly essential, being used in daily practice in critical care settings for various indications, either as a first-line therapeutic intervention or as an adjunct to conventional therapies. This retrospective clinical study analyzes 10-year therapeutic plasma exchange activity experience in an 18-bed ICU at a tertiary care university hospital with a large, critically-ill patient population. Medical records of 1188 plasma exchange procedures on 329 patients with different diagnoses admitted from January 2000 to July 2010 were evaluated. The aim of the study was to determine the TPE indications and outcomes of the patients who underwent TPE in the ICU with conventional therapy. The secondary endpoints were to determine the differences between different patient groups (septic vs. non-septic indications) in terms of adverse events and procedural differences.

Guidelines on the use of therapeutic apheresis in clinical practice--evidence-based approach from the Apheresis Applications Committee of the American Society for Apheresis

The American Society for Apheresis (ASFA) Apheresis Applications Committee is charged with a review and categorization of indications for therapeutic apheresis. Beginning with the 2007 ASFA Special Issue (fourth edition), the subcommittee has incorporated systematic review and evidence-based approach in the grading and categorization of indications. This Fifth ASFA Special Issue has further improved the process of using evidence-based medicine in the recommendations by refining the category definitions and by adding a grade of recommendation based on widely accepted GRADE system. The concept of a fact sheet was introduced in the Fourth edition and is only slightly modified in this current edition. The fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis. The article consists of 59 fact sheets devoted to each disease entity currently categorized by the ASFA as category I through III. Category IV indications are also listed.

Effect of plasmapheresis on the immune system in endotoxin-induced sepsis

BACKGROUND

It has been proposed that plasmapheresis is most effective when applied early in Gram-negative sepsis. We therefore studied the effect of early plasmapheresis on immunity in experimental Escherichia coli endotoxin-induced sepsis.

METHODS

20 pigs received 30 microg/kg of E. coli endotoxin. 40 min later, half of the pigs were treated with plasmapheresis which lasted 4 h. The adhesion molecules, the oxidative burst, the number of neutrophils in blood and lungs, and cytokines were measured.

RESULTS

Infusion of endotoxin was associated with activation of adhesion molecules increased oxidative burst, increased concentration of cytokine, and accumulation of granulocytes in lung tissue. Plasmapheresis reduced the oxidative burst, and there was a tendency towards a reduced accumulation of granulocytes in the lung.

CONCLUSION

Though plasmapheresis was initiated early after the endotoxin infusion, it only temporarily attenuated a part of the activated cell-mediated immunity.

Guidelines on the use of therapeutic apheresis in clinical practice—Evidence-based approach from the apheresis applications committee of the American society for apheresis

The American Society for Apheresis (ASFA) Apheresis Applications Committee is charged with a review and categorization of indications for therapeutic apheresis. This elaborate process had been undertaken every 7 years resulting in three prior publications in 1986, 1993, and 2000 of "The ASFA Special Issues." This article is the integral part of the Fourth ASFA Special Issue. The Fourth ASFA Special Issue is significantly modified in comparison to the previous editions. A new concept of a fact sheet has been introduced. The fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis. A detailed description of the fact sheet is provided. The article consists of 53 fact sheets devoted to each disease entity currently categorized by the ASFA. Categories I, II, and III are defined as previously in the Third Special Issue. However, a few new therapeutic apheresis modalities, not yet approved in the United States or are currently in clinical trials, have been assigned category P (pending) by the ASFA Clinical Categories Subcommittee. The diseases assigned to category IV are discussed in a separate article in this issue.

Extracorporeal Therapies in the Treatment of Sepsis: Experience and Promise

Desire to restore the balance of body elements has enamored physicians since the ancient practice of bloodletting. More recently, extracorporeal techniques have been employed in both adults and children in treating sepsis. Extracorporeal therapies include continuous renal replacement (CRRT), plasma-based removal techniques, and extracorporeal membrane oxygenation (ECMO). These treatments could theoretically 1) provide immunohomeostasis of pro- and anti-inflammatory cytokines and other sepsis mediators, 2) decrease organ microthrombosis through removal of pro-coagulant factors and modulating the impaired septic coagulation response in sepsis, and 3) provide mechanical support of organ perfusion during the acute septic episode to allow time for response to traditional sepsis therapies and antimicrobials. CRRT is beneficial in managing fluid overload and acute renal failure in sepsis. Removal of sepsis mediators through the technique is variable, and the outcome impact of CRRT on sepsis has not been definitively determined. High-flow CRRT has demonstrated benefit in septic adults. Intriguing early results suggest that plasma exchange could improve outcomes in both adults and children. Based on experience, ECMO is recommended for refractory septic shock in neonates and should be considered for use in children. Ongoing trials may help determine whether the promise of extracorporeal therapies translates into outcome improvement in septic children.

Quo vadis haemapheresis. Current developments in haemapheresis

The techniques of haemapheresis originated in the development of centrifugal devices separating cells from plasma and later on plasma from cells. Subsequently membrane filtration was developed allowing for plasma-cell separation. The unspecificity of therapeutic plasma exchange led to the development of secondary plasma separation technologies being specific, semi-selective or selective such as adsorption, filtration or precipitation. In contrast on-line differential separation of cells is still under development. Whereas erythrocytapheresis, granulocytapheresis, lymphocytapheresis and stem cell apheresis are technically advanced, monocytapheresis may need further improvement. Also, indications such as erythrocytapheresis for the treatment of polycythaemia vera or photopheresis though being clinically effective and of considerable importance for an appropriate disease control are to some extent under debate as being either too costly or without sufficient understanding of the mechanism. Other forms of cell therapy are under development. Rheohaemapheresis as the most advanced technology of extracorporeal haemorheotherapy is a rapidly developing approach contributing to the treatment of microcirculatory diseases and tissue repair. Whereas the control of a considerable number of (auto-) antibody mediated diseases is beyond discussion, the indication of apheresis therapy for immune complex mediated diseases is quite often still under debate. Detoxification for artificial liver support advanced considerably during the last years, whereas conclusions on the efficacy of septicaemia treatment are debatable indeed. LDL-apheresis initiated in 1981 as immune apheresis is well established since 24 years, other semi-selective or unspecific procedures, allowing for the elimination of LDL-cholesterol among other plasma components are also being used. Correspondingly Lp(a) apheresis is available as a specific, highly efficient elimination procedure superior to techniques which also eliminate Lp(a). Quality control systems, more economical technologies as for instance by increasing automation, influencing the over-interpretation of evidence based medicine especially in patients with rare diseases without treatment alternative, more insight into the need of controlled clinical trials or alternatively improved diagnostic procedures are among others tools ways to expand the application of haemapheresis so far applied in cardiology, dermatology, haematology, immunology, nephrology, neurology, ophthalmology, otology, paediatrics, rheumatology, surgery and transfusion medicine.

Plasma exchange as rescue therapy in multiple organ failure including acute renal failure

OBJECTIVE

To describe the outcome of using a rescue therapy including plasma exchange given to patients with a progressive acute disseminated intravascular coagulation and multiple organ dysfunction syndrome.

STUDY DESIGN

Retrospective study.

SETTING

University and county hospital.

PATIENTS

Included were 76 consecutive patients (41 men and 35 women) treated with plasma exchange as rescue therapy besides optimal conventional therapy during a progressive course of disseminated intravascular coagulation and multiple organ dysfunction syndrome, including acute renal failure. Of the 76 patients, 66% needed dialysis. The distribution was hemodialysis in 76%, continuous arteriovenous hemofiltration in 36%, continuous venovenous hemodialysis in 12%, and peritoneal dialysis in 24%. The median organ-failure score was 5 (range, 1-6). Seventy-two percent required mechanical ventilation; septic shock was present in 88%. The median septic shock score was 4 (range, 2-4). Nine patients had another reason than sepsis for the multiple organ dysfunction syndrome.

INTERVENTION

Plasma exchange (centrifugation technique) was performed until disseminated intravascular coagulation was reversed (median, two times; range, 1-14). Besides antibiotics and fluid administration, most patients received heparin or low molecular weight heparin (77%), steroids (87%), and inotropes (88%). More than one vasoactive drug was used in 57% of the patients.

MEASUREMENTS AND MAIN RESULTS

Eighty-two percent of the patients survived and could leave the hospital. The previously observed survival rates by others for this category of patients would be <20%, and thus, the outcome in this study is significantly better.

CONCLUSION

Plasma exchange using plasma as replacement may, in addition to conventional intensive care, help to reverse severe progressive disseminated intravascular coagulation and multiple organ dysfunction syndrome and improve survival.

Tratamiento del shock séptico con plasmafiltración y hemodiafiltración continuas simultáneas

Despite recent therapeutic advances, mortality due to septic shock remains high. The most important causes of mortality are refractory shock, uncontrollable alterations of coagulation, and multiorgan failure. Some authors have proposed the early use of plasmafiltration and high flow hemodiafiltration for refractory septic shock. Most authors initiate treatment with a short session of plasmafiltration followed by continuous hemodiafiltration. A 13-year-old girl presented refractory meningococcal septic shock, disseminated intravascular coagulation, and acute renal failure unresponsive to volume expansion and high doses of adrenalin and noradrenaline. She received simultaneous treatment with plasmafiltration and continuous venovenous hemodiafiltration for 30 hours. Two pumps of extrarenal purification placed in parallel through the same double line catheter were used. Fast hemodynamic stabilization and control of the coagulopathy were achieved. The patient survived with progressive recovery of renal function but required amputation of the inferior left limb. Continuous plasmafiltration and venovenous hemodiafiltration can be used simultaneously for the treatment of older children with septic shock, severe coagulopathy, and hypervolemia.

The use of extracorporeal techniques to remove humoral factors in sepsis

OBJECTIVE

To determine whether there is sufficient evidence of a benefit of hemofiltration or plasma filtration in sepsis.

DATA SOURCES

Medline search, search of references in articles found in Medline search, literature known to local experts.

STUDY SELECTION

Trials and reports where clinical outcome measures were included.

DATA EXTRACTION

Clinically relevant information was presented.

DATA SYNTHESIS

Studies were grouped according to hemofiltration or plasma filtration and within each of these groups into animal or human studies; then they were graded from case report, through case series, nonrandomized trials, and randomized trials.

CONCLUSION

There is a lack of randomized trials. The available studies show an absence of benefit for hemofiltration. Further studies are needed in plasma filtration.

Clinical review: extracorporeal blood purification in severe sepsis

Sepsis and septic shock are the leading causes of acute renal failure, multiple organ system dysfunction, and death in the intensive care unit. The pathogenesis of sepsis is complex and comprises a mosaic of interconnected pathways. Several attempts to improve patient outcomes by targeting specific components of this network have been unsuccessful. For these reasons, the ideal immunomodulating strategy would be one that restores immunologic stability rather than blindly inhibiting or stimulating one or another component of this complex network. Hence, the recent focus of immunomodulatory therapy in sepsis has shifted to nonspecific methods of influencing the entire inflammatory response without suppressing it. Here, we discuss the various modalities of extracorporeal blood purification, the existing evidence, and future prospects.

Diffuse alveolar hemorrhage in systemic lupus erythematosus: a single center retrospective study in Taiwan

This study is to describe our clinical experience of diffuse alveolar hemorrhage (DAH) in patients with systemic lupus erythematosus (SLE) in Taiwan. From July 1994 to June 2001, eight patients of DAH among 1541 different SLE patients (0.52%) admitted to the Chang Gung Memorial Hospital were included for chart review. Dyspnea (100%) and fever (87.5%) were the most common symptoms instead of hemoptysis (62.5%). The most common extrapulmonary presentation was renal involvement (100%), which included clinical nephritis, nephrotic syndrome or acute renal failure. The overall mortality rate was 50%. Two pregnant patients were successfully treated with combined plasmapheresis and continuous venovenous hemofiltration in addition to high dose corticosteroid. Analysis of the prognostic factors showed that the higher APACHE II (Acute physiology, Age and Chronic Health Evaluation) and organ system failure (OSF) scores, but not the SLE activity index (SLEDAI), were associated with the greater mortality. The higher serum creatinine level or the need of hemodialysis did not adversely affect the survival. In conclusion, DAH in SLE patients are often accompanied with multiple organ failure, aggressive immunosuppressive therapy and multiple modalities of extracorporeal organ support should be started early for a favorable outcome.

Extracorporeal treatment for septic patients: new adsorption technologies and their clinical application

Many kinds of blood purifying technologies have been applied to the treatment of critically ill patients since 1979 when plasma exchange with hollow fiber membranes was developed. These technologies have been applied not only to the removal of toxic substances, but also to the treatment of objective diseases and the removal of the factors relating to the associated inflammation. This article briefly summarizes these methods and their efficacies for critically ill patients, especially those with severe sepsis. Attempts have been made to remove endotoxin, the main cause of sepsis from the circulation, using polymyxin B-immobilized fiber, charcoal hemoperfusion, and plasma or whole blood exchange. Attempts have also been made to remove proinflammatory cytokines, eicosanoids, and coagulative factors from the circulation in the human body. Continuous hemofiltration or hemodiafiltration is representative technology. The efficacy of these methods has been established, but several issues remain unresolved. All methods of the treatment of severe sepsis are discussed with reference to treatment indications, efficacy, and outcome parameters. In particular, the clinical results of endotoxin removal with polymyxin B-immobilized fiber are summarized in this article.

Autonomic dysfunction in the ICU patient

The sympathetic-parasympathetic balance may be altered in critically ill patients. Assessment of autonomic function provides information concerning prognosis, pathogenesis, and treatment strategies in ICU-relevant disorders. Proven tools are heart rate variability, baroreflex sensitivity, and, with limitations, cardiac chemoreflex sensitivity. New nonlinear methods are being evaluated that may predict risk more precisely in critically ill patients. This article summarizes application of these tools in the ICU. In addition, a model is introduced for investigating the impaired autonomic function in multiple organ dysfunction syndrome and sepsis, integrating extrinsic mechanisms and factors that are intrinsic to the cardiac tissue. By this combined approach, the authors hope to gain insight into the pathogenesis of multiple organ dysfunction syndrome. New pathophysiologic concepts are needed for the development of treatment strategies for this life-threatening disease.

Current topics on cytokine removal technologies

It has been widely accepted that cytokines play important roles in the development of organ failure in various pathophysiological conditions of critically ill patients. Various new technologies, including continuous renal replacement therapy, have been developed for the removal of causative humoral mediators in sepsis or other critical conditions. Nonselective blood purification technologies, such as hemofiltration and plasma exchange, are applied in cytokine removal technology. However, the more selective blood purification technologies, such as adsorption, and the combination of those technologies, should be considered in future applications. Only through a prospective randomized controlled study can it be elucidated whether or not these technologies have efficacy in the treatment of sepsis and critically ill patients with hypercytokinemia. We should join and discuss the design of future clinical trials with a standardized strategy for the evaluation of the technologies.

Septic shock

Infection is problematic because it affects many patients (adults and children), is a major cause of death in intensive care units (ICU) worldwide, and uses a large amount of hospital resources. The mortality rate among patients with septic shock varies but approximates 40% in infected patients admitted to ICUs. Because of the large number of adults dying of sepsis, many resources are expended. Children are physiologically different from adults, but nonetheless, many similarities exist with respect to the response to septic shock.