Cryofiltration is the on—line technique of plasma treatment consisting of plasma cooling followed by membrane filtration. By cooling the plasma, cryogel is deposited on the membrane during the Filtration process. The cryogel has been shown to contain concentrated quantities of the marker solutes. Response to therapy in the majority of patients with rheumatoid arthritis has been from good to excellent. In treatments, decreases in marker solutes have been noted coupled with improvement in clinical sympto—mology.
Membrane technology appears very promising in the separation and treatment of plasma on—line. Chronic treatment therapies appear safe and well tolerated by the patients.
New words
centrifugal technique – центрифужные технологии
plasma exchange – плазмообмен
therapeutic – терапевтический
metabolic – метаболический
multiple – множественный
extracorporeal – экстракорпоральный
56. Artificial oxygen carries
Artificial oxygen (O 2) carries aim at improving O 2 delivery. Artificial 0 2 carries thus may be used as alternative to allogeneic blood transfusions or to improve tissue oxy—genation and function of organs with marginal O >2 supply. Artificial O >2 carries can be grouped into modified hemoglobin (Hb) solutions and perfluorocarbon (PFC) emulsions. The native human Hg molecule needs to be modified in order to decrease O >2 affinity and to prevent rapid dissociation of the native tetramer into dimers. The O >2 transport characteristics of modified Hb solutions and PFC emulsions are fundamentally different. The Hb solutions exhibit a sigmoidal O >2 dissociation curve similar to blood. In contrast, the PFC emulsions are characterised by a linear relationship between O >2 partial pressure and O >2 content. Hb solutions thus provide O >2 transport and unloading capacity similar to blood. This means that already at a relatively low arterial O >2 partial pressure substantial amounts of O >2 are being transported. In contrast, relatively high arterial O >2 partial pressures are necessary to maximize the O >2 transport capacity of PFC emulsions.
Modified Hb solutions are very promising in improving O >2 transport and tissure oxygenation to a physiologically relevant degree. Because cross—matching is unnecessary, these solutions hold great promise as alternative to allogeneic blood transfusions and as O >2 therapeutics, which might be of great value also in the prehospital resuscitation of trauma victims or in specific situations in intensive care medicine. In patients with a reduced cardiac contractility and normal or elevated mean arterial pressure Hb infusion may increase systemic and pulmonary vascular resistances with consequent reduction in cardiac output. In contrast, in a previously healthy trauma victim, suffering from severe hypovolaemia due to massive haemorrhage, the combined effects of volume replacement, added O