Plasma Filtration on Mediators of Thrombotic Microangiopathy: An in Vitro Study

Renal Replacement Therapy

During the last few years, due to medical and surgical evolution, patients with increasingly severe diseases causing multiorgan dysfunction are frequently admitted to intensive care units. Therapeutic options, when organ failure occurs, are frequently nonspecific and mostly directed towards supporting vital function. In these scenarios, the kidneys are almost always involved and, therefore, renal replacement therapies have become a common routine practice in critically ill patients with acute kidney injury. Recent technological improvement has led to the production of safe, versatile and efficient dialysis machines. In addition, emerging evidence may allow better individualization of treatment with tailored prescription depending on the patients' clinical picture (e.g. sepsis, fluid overload, pediatric). The aim of the present review is to give a general overview of current practice in renal replacement therapies for critically ill patients. The main clinical aspects, including dose prescription, modality of dialysis delivery, anticoagulation strategies and timing will be addressed. In addition, some technical issues on physical principles governing blood purification, filters characteristics, and vascular access, will be covered. Finally, a section on current standard nomenclature of renal replacement therapy is devoted to clarify the "Tower of Babel" of critical care nephrology.

Plasma exchange therapy for thrombotic microangiopathies

Thrombotic microangiopathies (TMAs) are syndromes associated with thrombocytopenia and multiple organ failure. Plasma exchange is a proven therapy for primary TMA such as thrombotic thrombocytopenic purpura (TTP). There is growing evidence that plasma exchange therapy might also facilitate resolution of organ dysfunction and improve outcomes for secondary TMAs such as disseminated intravascular coagulation (DIC) and systemic inflammation-induced TTP. In this review, we survey the current available evidence and practice of plasma exchange therapy for TMAs.

Multiple organ system extracorporeal support in critically ill children

Multiple organ system extracorporeal support effectively supports brain, heart, lung, liver, kidney, coagulation, red blood cell, and immune cell function in the sickest infants and children who have multiple organ system failure. These therapies have optimum benefit if: (1) the underlying disease is reversible; (2) the therapies are performed expertly and are monitored to prevent and minimize systemic hemolysis; and (3) the therapies are provided in a goal-directed manner. These therapies represent a significant advance in pediatric critical care medicine. This article provides a framework for this multidisciplinary team approach for implementing these therapies.

Potential interventions in sepsis-related acute kidney injury

Sepsis is an important cause of morbidity and mortality. Acute kidney injury often complicates sepsis, leading to greater complexity, cost of care, and worsening prognosis. In recent years, a consensus definition of acute kidney injury has been developed, facilitating research into the pathophysiology and epidemiology of this disorder. New and emerging biomarkers to recognize kidney injury before functional abnormalities are manifest may allow early recognition and facilitate prevention or treatment. Furthermore, advances in the clinical management of sepsis may have secondary benefits with respect to renal outcomes. Existing and hybrid extracorporeal therapies are being investigated not only as means to replace lost kidney function but also to modulate the immune response to sepsis. For those who have more advanced forms of kidney injury, strategies to promote renal recovery are being sought to minimize the long-term consequences of impaired kidney function. This review provides an update on the current state of the science and a glimpse toward the future of intervention in sepsis-related acute kidney injury.

Extracorporeal blood purification in sepsis and sepsis-related acute kidney injury

Sepsis-related acute kidney injury (AKI) is an important complicating feature of sepsis, and is associated with greater complexity of care and higher mortality. Until recently, AKI lacked a standard, widely accepted definition, rendering it difficult to compare previously published strategies to prevent, recognize and treat this entity. Recently, the RIFLE classification of AKI has been developed, and confirmed in observational studies to be associated with subsequent morbidity and mortality. The management of sepsis-related AKI is evolving with new basic discoveries and ongoing translational clinical research, and will likely include nephroprotective strategies to protect kidneys in patients at risk, early recognition and amelioration of renal damage and pharmacological interventions to minimize injury and promote recovery. Furthermore, extracorporeal blood purification (EBP) has an important role to play, not only in the replacement of certain aspects of renal organ function such as acid-base/electrolyte homeostasis and extracellular fluid volume, but also in an immunomodulatory fashion. As a therapy that has the potential to influence the course of disease in sepsis, EBP in sepsis and sepsis-related AKI is the subject of this review.