Preparation of fibrin glue: The effects of calcium chloride and sodium chloride

Concentrated fibrinogen is prepared from whole blood by cryoprecipitation and is then combined with a thrombin solution to make fibrin glue. Fibrin glue has been widely employed in many phases of surgery to control bleeding and to seal tissue defects. The purpose of this research was to study the effect of ionic strength of thrombin solutions on the properties of fibrin glue. Fresh bovine plasma was frozen at -15 degrees C for 24 h to prepare concentrated fibrinogen. The thrombin solution was prepared by reconstituting topical bovine thrombin with calcium chloride solutions to give a final concentration of 10, 20, 40, or 80 mM calcium chloride, with or without 0.9% w/v sodium chloride solution. The clotting time was measured by using a fibrometer and the bonding strength of fibrin glue was determined by measuring the force required to shear apart two collagen films joined by fibrin glue. The results showed that faster gelation was obtained when 20-40 mM calcium chloride was used. In contrast, the addition of physiologic saline (0.9% w/v sodium chloride), slowed down the gelation of all samples. It is concluded that high bonding strength and rapid formation of fibrin glue can be obtained using 10 units ml(-1) thrombin reconstituted with 20 mM calcium chloride solution, in the absence of sodium chloride.