Membrane plasma separation: complications and monitoring.

During the last 3 years, 306 membrane plasma separations (MPS) were performed on 40 patients. Activated partial thromboplastin time (APTT), oncotic pressure (OP), blood count, free hemoglobin, prothrombin time, fibrinogen, and factors II, V, VII, VIII, IX, X, XI, and XIII were determined. The complication rate was evaluated. Mild complications were observed in 4.2% of the cases (extracorporeal coagulation 1.5%, hypotensive episodes 2%, allergic reactions 0.7%). Severe complications were not observed. A flexible heparinization schedule dependent on the APTT values is necessary. In general, 4,500-7,000 IU/MPS is required. The serum OP is maintained within the normal range using a 3-6% human albumin solution to prevent circulatory complications. A marked loss of fibrinogen occurs with short intervals between successive treatments. The remaining coagulation factors are reduced by an average of 32% and the prothrombin time by 28%. Control of the heparinization and OP is essential for monitoring plasma exchange therapy.