After bleeding is controlled with hemostats during surgery, the residual material should be resorbed without adverse effects such as inflammation, infection or scar formation. To evaluate the biocompatibility of hemostats, three kinds of commercially available collagen hemostats, cotton type (Integran^®), microfibrillar type (Avitene^®), and sheet type (TachoComb^®), were examined. A rabbit ear chamber (REC), a system for viewing materials in vivo, was applied to the auricle of male Japanese white rabbits. The REC was designed to leave a 50-μm-thick and 6.4mm-diameter chamber, and 0.5mg of each specimen (Integran; n=8, Avitene; n=6, TachoComb; n=6) was placed in the chamber. Macroscopic and microscopic observations were performed every week up to 5 weeks without anesthetizing or stressing the animal. In the Integran group, capillaries infiltrated between the collagen fibers, and the vasculature in the REC field was complete in 6 out of 8 animals at 5 weeks. Cotton type collagen fibers of Integran became thinner every week without effusion. In the TachoComb group, capillaries were directed toward the effusion at 2 weeks, while in the Avitene group, a similar phenomenon was not observed. The vasculature was incomplete, with either effusion or infection at 5 weeks in the Avitene and TachoComb groups. Material was recognized up to 4 weeks in the TachoComb group, whereas the space occupied by material remained vacant without vasculature in the Avitene group. Our results suggest that cotton type configuration is excellent as a collagen hemostat, with smooth capillary infiltration, rapid resorption of material and promotion of the healing process.

When local hemostatic agents are used in surgery, rapid dissolution followed by prompt absorption without adverse effect after successful hemostasis are essential qualities. Residual hemostatic materials greatly influence host cells during the wound healing process. Biocompatibility of material is also essential. Furthermore, hemostatic agents also should be free of cytotoxicity that may block mitosis and migration of host cells, so that wound healing can proceed smoothly. For the evaluation of biocompatibility and cytotoxicity, 4 commercially available hemostatic agents; oxidized regenerated cellulose (Surgicel^®), gelatin sponge (Spongel^®), microfibrillar collagen (Avitene^®) and cotton type collagen (Integran^®) were tested in vitro and in vivo. The hydrogen ion concentration (pH) of culture medium containing hemostatic agents was measured. Fibroblasts were cultured with the hemostatic agents in petri dishes for 5 days. A rabbit ear chamber (REC) model was used to evaluate tissue compatibility and the healing process. Each hemostatic agent was placed in the REC and evaluated macroscopically once a week up to 5 weeks. At 72h, the pH of the culture medium containing Surgicel was low at 7.2, while they stayed between 7.7-7.8 with the other agents. In the fibroblast culture containing Surgicel, cell detachment occurred and the cell numbers decreased, while no particular changes occurred with other hemostatic agents. In the REC model, after 5 weeks Surgicel was dissolved and remained in the effusion, and the healing process was disturbed by inflammation. Spongel was dissolved and absorbed, with normal vasculature. Avitene was dissolved and remained in the effusion, but did not induce strong inflammation. With Integran, the healing process was prompt but the material was still recognizable at 5 weeks. The 4 hemostatic materials tested showed differences in biocompatibility and cytotoxicity. The ability of hemostasis is important; however, after hemostasis is achieved, unused hemostatic material should be eliminated, leaving as little hemostatic agent as possible to avoid postoperative complications.

Objective : In 2011, the Ishikawa Prefectural Joint Committee of Blood Transfusion Therapy was organized in Ishikawa Prefecture. Since 2012, pharmacists have promoted educational activities regarding the appropriate use of albumin products for different occupations based on a survey involving all medical institutions in Ishikawa Prefecture. We examined the effects of these activities with respect to the usage of albumin products. Methods : A questionnaire survey regarding blood transfusion therapy, including the total usage of albumin products, departments responsible for the management of albumin products, and health care professionals’ awareness of issues on the appropriate use of albumin products, was conducted from 2011 until 2014 involving all medical institutions where blood transfusion preparations were used in Ishikawa Prefecture. Results : The questionnaire collection rate was ≥70%. The results showed that, in middle- or small-scale medical institutions, departments/physicians other than the Department of Pharmacy were responsible for the management of albumin products. Furthermore, some health care professionals did not recognize/understand problems regarding the appropriate use of albumin products. Pharmacists newly increased educational activities by study meetings for various occupations or panel discussions involving participants. The participants’ occupations varied, and the number of institutions to which they belonged was 20 to 24. The total usage of albumin products in Ishikawa Prefecture decreased by approximately 20% between 2011, when these attempts were started, and 2014. Discussion : This study suggests that the educational activities by pharmacists and other health care professionals at the prefectural level reduced the total usage of albumin products.