Filtration of Fresh Frozen Plasma Used As Substitution Fluid in Plasma Exchange in Order to Remove Microaggregates

Abstract

Freshly melted fresh frozen plasma (FFP) contains a large number of particles smaller than 20 .mu.m in diameter. These particulate materials (microaggregates) consist of aggregated triglyceride-rich lipoproteins (LA) and precipitable aggregates closely resembling fibrin (FA). Both LA and FA injected into a rat''s tail vein were trapped in the lung and formed emboli in the pulmonary arterioles. To prevent the passage of these microaggregates into the systemic circulation, a new circuit was devised for plasma exchange containing a filter with a pore size of 0.2 .mu.m. In 17 patients with fulminant hepatitis who received plasma exchange transfusions and subsequently died and were autopsied, the incidence of pulmonary complications was significantly lower in the 12 patients who received filtered FFP. According to these results, the possibility of pulmonary complications due to microembolism developed by microaggregates in FFP should be taken into account when a large amount of FFP is repeatedly infused into critically ill patients.