A novel modified thaw‐siphon method for extracting cryoprecipitate: The Bokutoh‐siphon method

Abstract

Background Cryoprecipitate (CRYO) is neither produced nor supplied by the Japanese Red Cross Society. A novel CRYO extraction method established in‐house by modifying a thaw‐siphon technique was demonstrated in this study. Study Design and Methods A pack of fresh frozen plasma was thawed and equally divided into two bags for CRYO extraction by different methods. CRYO was extracted from the blood plasma using a standard centrifugation method and our modified thaw‐siphon method (Bokutoh‐siphon method; B method). The two different CRYOs extracted were analyzed to compare the differences in the amount of fibrinogen recovered, clotting factors extracted, and clotting activity. Results The amount of fibrinogen in the CRYO extracted using the B‐siphon method was similar to that obtained using the standard method (recovery of fibrinogen: B‐siphon method: 71.2% vs. standard method: 61.0%). The amount of clotting XIII factor extracted using the B‐siphon method was significantly lower than those extracted using the standard method. On the other hand, clotting II, V factors, and C1q esterase inhibitor not concentrated in CRYO content from the B‐siphon method were significantly higher than that from the standard method. Conclusion A new in‐house CRYO preparation method was established by modifying a previously used thaw‐siphon method. A coagulation factor‐rich CRYO was extracted from plasma frozen at −40°C along with the first fraction of thawed plasma, without using a large‐capacity refrigerated centrifuge for blood bags.