Skin graft fixation using fibrin sealant has been widely performed since the late 2000s (Gibran et al. 2007; Mittermayr et al. 2006; Buckley et al. 1999; Currie et al. 2001; Llanos et al. 2006). Via hemostasis and adhesion, fibrin glue fixes the graft and creates an ultrafine fibrin sealant matrix structure to diffuse nutrients and cytokines, promote neovascularization, and facilitate growth of fibroblasts and capillary endothelial cells by serving as a scaffold. This structure then promotes phagocytosis and blocks the source of infection (Gibran et al. 2007; Mittermayr et al. 2006; Currie et al. 2001; Foster et al. 2008; Jabs et al. 1992).
Although skin graft fixation using fibrin sealant has proved useful for graft take, fibrin sealant is not widely used compared with sutures or skin staples, primarily due to difficulty in obtaining sealant containing low-concentration thrombin. Fibrin sealant contains thrombin and fibrinogen as active components; when these 2 ingredients are mixed, fibrin clots are formed (Sierra et al. 2000). When thrombin concentration is high, fibrin clots are formed quickly, whereas, when thrombin concentration is low, they are formed slowly. According to previous studies, low-concentration fibrin sealant containing approximately 4 IU/mL thrombin is recommended because fibrin clots are formed slowly, permitting graft placement. In addition, because such sealant is easy to manipulate, the graft take rate can be enhanced (Mittermayr et al. 2006; Grabosch et al. 1994). When undiluted fibrin sealant which contains a thrombin concentration of 400 IU/mL is applied to the human body, clots are formed quickly; thus, such sealant is used clinically as a hemostatic agent. Some fibrin sealants containing 4 IU/mL thrombin are restrictedly available in Europe. As an alternative, autologous blood can be collected to prepare the sealant, but the preparation process is complicated and time-consuming.
To overcome these problems, in this study, undiluted fibrin sealant was applied directly to the wound, and skin grafting was performed directly. Not only is the surgical method simplified, but the total time needed is shortened. The disadvantage of fast-clotting fibrin sealant is the formation of clots before the graft adheres to the wound bed, preventing their use as glue. When fast-clotting fibrin sealant was used in this study, clots were formed before graft application, and weaker adhesion was noted compared with low-concentration sealant. Nevertheless, little graft dislocation was observed at the time of first dressing change at 5 days postoperatively, and little graft necrosis was observed 30 days postoperatively.
Although small differences were found in graft take rate and graft necrosis between group I and group II, the numbers were statistically insignificant. It is common that many surgeons believe using staples and/or sutures are mandatory in graft fixation while using fibrin glue only makes them feel uncomfortable and insufficient. However, this study has demonstrated that using fibrin glue only in graft fixation is as effective as conventional methods. Furthermore, the results have even surpassed conventional methods particularly in joints and extremities.
For skin graft take, it is important to prevent hematoma/seroma development and the resulting inhibition of blood vessel ingrowth in the graft, which plays a critical role in graft failure. This study revealed that adhesion tension of the split-thickness skin graft during surgery was irrelevant to successful grafting. Fast-clotting fibrin sealant was proven to be effective for clinical use by avoiding hematoma formation.
In addition, the study has revealed that graft necrosis is proportional to area of skin graft both in groups. However, group I showed the less correlation coefficient compared to group II, it can be assumed that fibrin sealant (group I) could be more effective in large area grafting.
Sealant application thickness is also important for successful graft take. When the fibrin sealant layer is excessively thick, nutrition supply and neovascularization for the host and graft may be inhibited. This problem can occur with both fast- and slow-clotting fibrin sealants (Mittermayr et al. 2006). This problem can be solved by applying the sealant with a spray. A thin application with a thickness of 0.05–0.06 mL/cm2 has been reported to enhance the graft take rate (Mittermayr et al. 2006; Spies et al. 2001).
Use of fibrin sealant would be advantageous for patients if it could be obtained easily. Because fibrin sealant biodegrades within 2 weeks, foreign bodies, such as sutures and staples, are not left in the wound, especially in the granulation bed. In addition, patients often report severe pain when staples are removed, and occasionally, an anesthetic procedure is required (O’Grady et al. 2000; Batra et al. 2016; Himel et al. 1994; Best et al. 1995; Ghosh et al. 2015). Because fibrin sealant adheres to the entire surface, hematoma/seroma formation is significantly reduced compared with point-fixation sutures or staples (Cha et al. 2012; Gibran et al. 2007; Llanos et al. 2006; Myer et al. 2015; Mabrouk et al. 2013). According to previous studies, fibrin sealant is effective for graft take, particularly in joint and extremity areas that experience difficulty in postoperative immobilization. In addition, suture and staple marks are not formed, and the frequency of hypertrophic scar development caused by ischemic mechanical fixation is reduced (Mittermayr et al. 2006). Moreover, the enhanced graft take rate can result in decreased hospital stay as well as scar management costs, leading to overall cost savings even though fibrin sealant is more expensive and this cost could influence the total cost (Mittermayr et al. 2006). However, commercially available fibrin sealants contain bovine aprotinin and thrombin, which can theoretically result in transmission of Creutzfeldt-Jakob disease or other viral diseases (Currie et al. 2001).
As described previously, use of fibrin sealant can overcome the disadvantages associated with sutures and staples. Fibrin sealant has been used for skin graft fixation since 2000, and comparative studies on the thickness of the sealant layer have been reported (Mittermayr et al. 2006; Spies et al. 2001). However, few studies on the effect of thrombin concentration have been published. A limitation of this study is lack of comparison between low- and high-thrombin concentration groups. And randomized trials will need to be performed in order to verify our result.