Use Of Plasma Exchange Research Articles

Plasma exchange therapy in progressive systemic sclerosis

Eight patients with severe progressive systemic sclerosis were treated with plasma exchange accompanied by cyclophosphamide and/or captopril, a converting enzyme inhibitor. All patients presented with visceral involvement of heart, lung, or kidney, and/or extensive skin lesions with tissue necrosis. Raynaud's syndrome improved in all patients after plasma exchange, and all patients showed an objective improvement in their most prominent clinical features, resulting in reduction of heart failure, improvement in lung function tests, decrease in creatinemia, and healing of ulcers. These results suggest the use of plasma exchange either with short courses of intensive exchanges for vasculitis or acute kidney or heart involvement, or with longer courses of regular exchanges for pulmonary fibrosis. Four deaths were observed, but follow-up (up to 62 months) showed the possibility of a long term stability under captopril therapy in patients with poor prognosis.

Blood Detoxification by Membrane Plasma Filtration

The recognition of macromolecule abnormalities in various metabolic or immunologic related disease states has led to the use of plasma exchange for therapeutics. Limitations of plasma exchange, however, exist. Membrane plasma filtration provides a practical alternative. Solute removal can be made selective by the choice of operating conditions as temperature and the selection of the membrane/module design. The optimal temperature range is a function of the plasma type, solute concentrations and membrane system. Operation at below physiologic temperature (cryofiltration) is particularly suited for the removal of cold aggregative solutes, while operation at near or above physiologic temperature is more suited for the separation of solutes having large size differences at normal physiologic temperature. Membrane filtration is simple and safe to perform, is more selective than plasma exchange, does not require plasma product infusion and is more versatile than selective sorption in its applications.

Plasma exchange in neurologic diseases.

Plasma exchange has become increasingly popular as a mode of therapy in putative immunopathologic diseases of man, including several disorders of interest to neurologists. Among these are myasthenia gravis (MG), demyelinative neuropathies (acute, relapsing, and chronic progressive), inflammatory myopathies, Eaton-Lambert syndrome (ELS), multiple sclerosis (MS), and amyotrophic lateral sclerosis (ALS). Despite, or perhaps because of, the intense interest in and enthusiasm for this form of therapy, firm evidence of therapeutic efficacy in neurologic diseases is limited to MG. In this article, I will review the use and rationale for plasma exchange in these neurologic disorders and outline my personal view of the current role and use of plasma exchange in these diseases. MG Myasthenia gravis can be considered a prototype antibody-mediated autoimmune disease in which the pathogenesis of neuromuscular weakness can be attributed to a decrease in available nicotinic receptors for acetylcholine at the muscle end-plate. 1-4 This decrease is

Elimination kinetics of plasma exchange.

Interest in the therapeutic use of plasma exchange for various diseases is growing. The two different effects of plasma exchange are elimination and activation. The kinetics are linear for elimination by plasma exchange, but not for activation. Plasma exchange is performed intermittently and can be described by intermittent kinetics. According to intermittent kinetics, plasma exchange removes 50% to 75% of a substance in plasma within 1-2 h, corresponding to an elimination half-life of 30-40 min. Hybrid kinetics, a mixture of actually intermittent but theoretically continuous elimination by plasma exchange, can however also be applied. Hybrid kinetics are more convenient and more reliable than intermittent kinetics. This is because hybrid kinetics are based solely on the concentrations before each plasma exchange; hybrid kinetics also reflect removal from the entire body and not just from the plasma compartment. According to hybrid kinetics, the amount of a substance in the body removed within 3-4 days is 50% of the difference between the initial and the final plasma concentration, depending on the intensity of plasma exchange. The intensity may well contribute at least in part to the beneficial effect of plasma exchange in various diseases.

Plasma exchange therapy in patients failing to resuscitate from burn shock.

Irreversible burn shock results from failure of fluid resuscitation and is almost invariably fatal. Because of the implied role of circulating serum factors in the generation of burn shock, the use of plasma exchange was evaluated retrospectively in patients with major thermal injuries who had failed to respond to conventional therapy. Twenty-two patients with a mean burn size of 47.9% total body surface area and a mean age of 22.7 years underwent plasma exchange for ongoing burn shock after standard fluid resuscitation failed. A therapeutic response was documented in 95.4% of the patients, characterized by a sharp decrease in fluid requirements from a mean of 260% above the predicted hourly volume to within calculated requirements by 2.3 hours following plasma exchange. Markedly improved urine output and resolution of lactic acidosis were also demonstrated. No major complications occurred. We conclude that plasma exchange facilitates resuscitation from burn shock in a select group of patients who do not respond to conventional volume therapy.

Caution about the use of plasma exchange in the treatment of myasthenia gravis

Caution about the use of plasma exchange in the treatment of myasthenia gravis

Clinical Research: The Use of Plasma Exchange in Thermally Injured Patients Not Responding to Conventional Burn Management

Clinical Research: The Use of Plasma Exchange in Thermally Injured Patients Not Responding to Conventional Burn Management

Plasma-exchange ten years later.

In the past ten years plasma-exchange has been widely used to treat a large number of diseases, but clinical indications of the procedure are still a matter of debate since adequate clinical trials have yet to be completed. For the future, a more judicious use of plasma-exchange seems warranted. A national register of the procedure has been recently implemented also in Italy, kept by theCentro Trasfusionale of theOspedale Policlinico, Milano.

Postpartum Hemolytic Uremic Syndrome

To the Editor.— My compliments to Spencer et al for an excellent clinical outcome by the use of plasma exchange in a female patient thought to have postpartum hemolytic uremic syndrome (HUS) (1982;247:2808). Unfortunately, the authors have fallen into the clinical trap of describing the trees but missing the forest. The condition present in their patient is a variant of severe preeclampsia comprised of microangiopathic hemolytic anemia, which caused the hemolysis (H), elevated levels of liver enzymes (EL), and thrombocytopenia (LP indicates low platelet count). 1 The term HELLP syndrome has been given to this compilation of symptoms that may occur ante partum or post partum. The treatment described of plasma exchange has been used at the University of Arizona, Tucson, as well as by other investigators. 2 The various forms of preeclampsia are often misdiagnosed, resulting in excessive perinatal and maternal morbidity and mortality. 3 The clinician who is

Combined use of Plasma Exchange and Whole-Body Counting to Study Non-Steady-State Turnover of 131I-Low Density Lipoprotein

Combined use of Plasma Exchange and Whole-Body Counting to Study Non-Steady-State Turnover of 131I-Low Density Lipoprotein