Engineering safety study of a circuit conducting simultaneous hemodialysis and plasma exchange

Abstract

Clinical reports have stated that hemodialysis and experimental plasma exchange must be carried out at the same time. In reality, these medical treatments are performed separately, which increases the course of the patient's treatment. To shorten the duration of treatment and improve patients' quality of life, we developed a circuit for simultaneous hemodialysis and experimental plasma exchange. The aim of the current study was investigate the engineering safety of this hemodialysis and plasma exchange circuit. The circuit (DFPP- 21-HD), a hemodialyzer (DBB-72), plasma exchange equipment (Pulasort iQ21), a dialyzer (PS-1.6N), a plasma separator (Plasmacure PE08), and a second filter (Evafiux 2A-F) were used in the study. Double-filtration plasmapheresis (DFFP) was selected for the experimental plasmapheresis mode. Priming volume and pressure were measured using the circuit aqueous solution's coefficient of viscosity, and the damage to blood cells in the extended circuit was evaluated using cattle blood (5 liters at 40% hematocrit). The priming volume for the DFPP-21-HD circuit was 182 ml. The circuit pressure was measured by changing the flow, mirroring values at 40% hematocrit, which was prepared by adjusting the viscosity of the aqueous solution. Blood cell damage was investigated at a blood flow of 100 ml/min and a separator flow of 30 ml/min. Arterial blood samples were obtained at 15-min intervals for seven cycles. There were minimal changes in the serum potassium level and the hematocrit. This study demonstrates minimal blood cell damage due to priming volume and circuit pressure variations, indicating little danger to the patient. Circuit DFPP-21-HD is a safe technical design that can be applied for clinical hemodialysis and plasmapheresis. © 2013 Springer-Verlag.