Plasma Filtration Adsorption Dialysis (PFAD): A New Technology for Blood Purification

Nomenclature of Extracorporeal Blood Purification Therapies for Acute Indications: The Nomenclature Standardization Conference

The development of new extracorporeal blood purification (EBP) techniques has led to increased application in clinical practice but also inconsistencies in nomenclature and misunderstanding. In November 2022, an international consensus conference was held to establish consensus on the terminology of EBP therapies. It was agreed to define EBP therapies as techniques that use an extracorporeal circuit to remove and/or modulate circulating substances to achieve physiological homeostasis, including support of the function of specific organs and/or detoxification. Specific acute EBP techniques include renal replacement therapy, isolated ultrafiltration, hemoadsorption, and plasma therapies, all of which can be applied in isolation and combination. This paper summarizes the proposed nomenclature of EBP therapies and serves as a framework for clinical practice and future research.

Complement Inhibition Therapy and Dialytic Strategies in Paroxysmal Nocturnal Hemoglobinuria: The Nephrologist's Opinion

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal disease that presents an estimated incidence of 1.3 cases per million per year, with a prevalence of 15.9 cases per million. It is characterized by hemolysis, bone marrow dysfunction with peripheral blood cytopenia, hypercoagulability, thrombosis, renal impairment and arterial and pulmonary hypertension. Hemolysis and subsequent hemosiderin accumulation in tubular epithelium cells induce tubular atrophy and interstitial fibrosis. The origin of PNH is the somatic mutation in the X-linked phosphatidylinositol glycan class A (PIG-A) gene located on Xp22: this condition leads to the production of clonal blood cells with a deficiency in those surface proteins that protect against the lytic action of the activated complement system. Despite the increased knowledge of this syndrome, therapies for PNH were still only experimental and symptomatic, until the introduction of the C5 complement blockade agent Eculizumab. A second generation of anti-complement agents is currently under investigation, representing future promising therapeutic strategies for patients affected by PNH. In the case of chronic hemolysis and renal iron deposition, a multidisciplinary approach should be considered to avoid or treat acute tubular injury or acute kidney injury (AKI). New promising perspectives derive from complement inhibitors and iron chelators, as well as more invasive treatments such as immunoadsorption or the use of dedicated hemodialysis filters in the presence of AKI.

Treatment of AECHB and Severe Hepatitis (Liver Failure)

This chapter describes the general treatment and immune principles and internal management for AECHB and HBV ACLF, including ICU monitoring, general supportive medications/nutrition/nursing, immune therapy, artificial liver supportive systems, hepatocyte/stem cell, and liver transplant, management for special populations, frequently clinical complications and the utilization of Chinese traditional medicines.

Early clinical indicators of severe hepatitis B include acratia, gastrointestinal symptoms, a daily increase in serum bilirubin >1 mg/dL, toxic intestinal paralysis, bleeding tendency and mild mind anomaly or character change, and the presence of other diseases inducing severe hepatitis. Laboratory indicators include T-Bil, PTA, cholinesterase, pre-albumin and albumin. The roles of immune indicators (such as IL-6, TNF-α, and fgl2), gene polymorphisms, HBV genotypes, and gene mutations as early clinical indicators.

Intensive Care Unit monitor patients with severe hepatitis include intracranial pressure, infection, blood dynamics, respiratory function, renal function, blood coagulation function, nutritional status and blood purification process. Nursing care should not only include routine care, but psychological and special care (complications).

Nutrition support and nursing care should be maintained throughout treatment for severe hepatitis. Common methods of evaluating nutritional status include direct human body measurement, creatinine height index (CHI) and subject global assessment of nutrition (SGA). Malnourished patients should receive enteral or parenteral nutrition support.

Immune therapies for severe hepatitis include promoting hepatocyte regeneration (e.g. with glucagon, hepatocyte growth factor and prostaglandin E1), glucocorticoid suppressive therapy, and targeting molecular blocking. Corticosteroid treatment should be early and sufficient, and adverse drug reactions monitored. Treatments currently being investigated are those targeting Toll-like receptors, NK cell/NK cell receptors, macrophage/immune coagulation system, CTLA-4/PD-1 and stem cell transplantation.

In addition to conventional drugs and radioiodine, corticosteroids and artificial liver treatment can also be considered for severe hepatitis patients with hyperthyreosis. Patients with gestational severe hepatitis require preventive therapy for fetal growth restriction, and it is necessary to choose the timing and method of fetal delivery. For patients with both diabetes and severe hepatitis, insulin is preferred to oral antidiabetic agents to control blood glucose concentration. Liver toxicity of corticosteroids and immune suppressors should be monitored during treatment for severe hepatitis in patients with connective tissue diseases including SLE, RA and sicca syndrome. Patient with connective tissue diseases should preferably be started after the antiviral treatment with nucleos(t)ide analogues.

An artificial liver can improve patients’ liver function; remove endotoxins, blood ammonia and other toxins; correct amino acid metabolism and coagulation disorders; and reverse internal environment imbalances. Non-bioartificial livers are suitable for patients with early and middle stage severe hepatitis; for late-stage patients waiting for liver transplantation; and for transplanted patients with rejection reaction or transplant failure. The type of artificial liver should be determined by each patient’s condition and previous treatment purpose, and patients should be closely monitored for adverse reactions and complications. Bio- and hybrid artificial livers are still under development.

MELD score is the international standard for choosing liver transplantation. Surgical methods mainly include the in situ classic type and the piggyback type; transplantation includes no liver prophase, no liver phase or new liver phase. Preoperative preparation, management of intraoperative and postoperative complications and postoperative long-term treatment are keys to success.

Severe hepatitis belongs to the categories of “acute jaundice”, “scourge jaundice”, and “hot liver” in traditional Chinese medicine. Treatment methods include Chinese traditional medicines, acupuncture and acupoint injection, external application of drugs, umbilical compress therapy, drip, blow nose therapy, earpins, and clysis. Dietary care is also an important part of traditional Chinese medicine treatment.

Antimicrobial peptides: the LPS connection

An expanding body of evidence is rendering manifest that many cationic antimicrobial peptides are endowed with different properties and activities, well beyond their direct action on microbes. One of the most interesting and potentially important research avenue on the alternative use of antimicrobial peptides grounds on their affinity toward lipopolysaccharide (LPS), the endotoxin, responsible for the systemic inflammatory response syndrome (SIRS) and related, often fatal, disorders that can follow Gram-negative infections. Indeed, not only do several antimicrobial peptides, such as cathelicidins, display an ability to strongly bind LPS and break its aggregates, but they have also been demonstrated to suppress LPS-induced pro-inflammatory responses in vitro and to protect from sepsis in animal models. Although many aspects still need to be carefully evaluated - some of which are highlighted here - a mix of antimicrobial, LPS-sequestering/neutralization, and immunomodulatory features make cationic peptides, and especially synthetic or semi-synthetic amphiphilic compounds built on their scheme, attractive candidates for novel drugs to be administered in antisepsis therapies. These therapies will probably hinge either on compounds able to intervene at multiple points in the sepsis cascade or on the combination of two or more immunomodulators.

Impact of continuous venovenous hemofiltration on organ failure during the early phase of severe sepsis: a randomized controlled trial

OBJECTIVE

The impact of continuous venovenous hemofiltration on sepsis-induced multiple organ failure severity is controversial. We sought to assess the effect of early application of hemofiltration on the degree of organ dysfunction and plasma cytokine levels in patients with severe sepsis or septic shock.

DESIGN

Prospective, randomized, open, multicenter study setting, 12 French intensive care units.

PATIENTS

A total of 80 patients were enrolled within 24 hours of development of the first organ failure related to a new septic insult.

INTERVENTIONS

Patients were randomized to group 1 (HF), who received hemofiltration (25 mL/kg/hr) for a 96-hour period, or group 2 (C) who were managed conventionally.

MEASUREMENTS AND MAIN RESULTS

The primary end point was the number, severity, and duration of organ failures during 14 days, as evaluated by the Sepsis-Related Organ Failure Assessment score, on an intention-to-treat analysis. Strict guidelines were provided to perform continuous hemofiltration under the same conditions and bearing the same objectives in all centers. Because of inclusion stagnation, the trial was discontinued after an interim analysis by which time 76 patients had been randomized. The number and severity of organ failures were significantly higher in the HF group (p < 0.05). No modifications in plasma cytokine levels could be detected.

CONCLUSION

These data suggest that early application of standard continuous venovenous hemofiltration is deleterious in severe sepsis and septic shock. This study does not rule out an effect of high-volume hemofiltration (>35 mL/kg/hr) on the course of sepsis.

Renal replacement therapy in the treatment of acute renal failure-intermittent and continuous

Renal replacement therapy (RRT) is increasingly used in intensive care as acute renal failure (ARF) is a common and constantly increasing complication in this setting. Different forms of RRT such as intermittent hemodialysis, continuous hemofiltration, or hybrid forms, which combine advantages of both, are available and will be discussed in this article. As a general survival benefit for neither method has been demonstrated, it is the task of the nephrologist or intensivist to choose the RRT strategy that is most advantageous for each individual patient. The choice of RRT might depend not only on the underlying disease, the time course of the disease, the etiology of ARF, the actual clinical status of the patient but also on the resources available and the cost of therapy. An adequate dose of RRT seems to result in improved survival in patients with ARF. However, clear guidelines on the dose of RRT and the timing of initiation are still lacking. Moreover, it will be discussed whether patients with sepsis and septic shock benefit from early RRT initiation, the use of increased RRT doses, and increased removal of inflammatory mediators by RRT.

Interaction of antimicrobial peptide temporin L with lipopolysaccharide in vitro and in experimental rat models of septic shock caused by gram-negative bacteria

Sepsis remains a major cause of morbidity and mortality in hospitalized patients, despite intense efforts to improve survival. The primary lead for septic shock results from activation of host effector cells by endotoxin, the lipopolysaccharide (LPS) associated with cell membranes of gram-negative bacteria. For these reasons, the quest for compounds with antiendotoxin properties is actively pursued. We investigated the efficacy of the amphibian skin antimicrobial peptide temporin L in binding Escherichia coli LPS in vitro and counteracting its effects in vivo. Temporin L strongly bound to purified E. coli LPS and lipid A in vitro, as proven by fluorescent displacement assay, and readily penetrated into E. coli LPS monolayers. Furthermore, the killing activity of temporin L against E. coli was progressively inhibited by increasing concentrations of LPS added to the medium, further confirming the peptide's affinity for endotoxin. Antimicrobial assays showed that temporin L interacted synergistically with the clinically used beta-lactam antibiotics piperacillin and imipenem. Therefore, we characterized the activity of temporin L when combined with imipenem and piperacillin in the prevention of lethality in two rat models of septic shock, measuring bacterial growth in blood and intra-abdominal fluid, endotoxin and tumor necrosis factor alpha (TNF-alpha) concentrations in plasma, and lethality. With respect to controls and single-drug treatments, the simultaneous administration of temporin L and beta-lactams produced the highest antimicrobial activities and the strongest reduction in plasma endotoxin and TNF-alpha levels, resulting in the highest survival rates.