MON-099 Particulates mixed in dialysate

Abstract

When foreign bodies that cannot be metabolized enter the systemic circulation, they remain in the body and are often difficult to remove. Therefore, each country’s pharmacopoeia measures insoluble particulates that are unintentionally mixed into injections and manages quality control by the predetermined permissible range of insoluble particulates. However, the present Standard of Fluids for Hemodialysis and Related Therapies only stipulates the water quality standard for biological and chemical contaminants, but there is no standard for insoluble particulates in dialysate. We measured insoluble particulates in online prepared substitution fluid prepared from dialysate and substitution fluid for hemofiltration and evaluated the insoluble particulates using scanning electron microscopy/energy dispersive spectroscopy. We measured insoluble particulates in online prepared substitution fluid prepared by filtering dialysate using an endotoxin retentive filter installed in the central dialysis fluid delivery system and commercially-available substitution fluid for hemofiltration. We used the Light Obscuration Particle Count Test for measurement, as stipulated by Japanese pharmacopoeia. We evaluated the constituent elements of insoluble particulates using scanning electron microscopy/energy dispersive spectroscopy. We also measured silicon contained in reverse osmosis water used to prepare dialysate in the central dialysis fluid delivery system and substitution fluid for hemofiltration. The mean number of particles of ≥ 10 μm contained in the online prepared substitution fluid was 0.1–1 /mL and 0–0.1 /mL for particles of ≥ 25 μm. Insoluble particulate elements included carbon, oxygen, calcium, magnesium, and silicon. The silicon content of reverse osmosis water was 0.5 mg/L. The mean number of particles of ≥ 10 μm contained in substitution fluid for hemofiltration was 0.5 /mL, with no particles ≥ 25 μm. These insoluble particulates were composed of carbon and oxygen. The silicon content was 0.1 mg/L. Japanese pharmacopoeia stipulates that the number of insoluble particulates in 1 mL of injection fluid must be 25 or fewer for particles of ≥ 10 μm and 3 or fewer for particles of ≥ 25 μm. The numbers of insoluble particles in online prepared substitution fluid and substitution fluid for hemofiltration were within permissible ranges, as stipulated by Japanese pharmacopoeia. We presume that insoluble particulates in online prepared substitution fluid were calcium and magnesium precipitated from dialysate and silicon precipitated from reverse osmosis water. The insoluble particulates in the substitution fluid for hemofiltration were carbon and oxygen, which were presumed to be components of glucose based on the composition of hemofiltration substitution fluid.