Hemostatic wound dressings: Predicting their effects by in vitro tests

Cryopreserved nanostructured fibrin-agarose hydrogels are efficient and safe hemostatic agents

Uncontrolled bleeding during surgery is associated with high mortality and prolonged hospital stay, necessitating the use of hemostatic agents. Fibrin sealant patches offer an efficient solution to achieve hemostasis and improve patient outcomes in liver resection surgery. We have previously demonstrated the efficacy of a nanostructured fibrin-agarose hydrogel (NFAH). However, for the widespread distribution and commercialization of the product, it is necessary to develop an optimal preservation method that allows for prolonged stability and facilitates storage and distribution. We investigated cryopreservation as a potential method for preserving NFAH using trehalose. Structural changes in cryopreserved NFAH (Cryo-NFAH) were investigated and comparative in vitro and in vivo efficacy and safety studies were performed with freshly prepared NFAH. We also examined the long-term safety of Cryo-NFAH versus TachoSil in a rat partial hepatectomy model, including time to hemostasis, intra-abdominal adhesion, hepatic hematoma, inflammatory factors, histopathological variables, temperature and body weight, hemocompatibility and cytotoxicity. Structural analyses demonstrated that Cryo-NFAH retained most of its macro- and microscopic properties after cryopreservation. Likewise, hemostatic efficacy assays showed no significant differences with fresh NFAH. Safety evaluations indicated that Cryo-NFAH had a similar overall profile to TachoSil up to 40 days post-surgery in rats. In addition, Cryo-NFAH demonstrated superior hemostatic efficacy compared with TachoSil while also demonstrating lower levels of erythrolysis and cytotoxicity than both TachoSil and other commercially available hemostatic agents. These results indicate that Cryo-NFAH is highly effective hemostatic patch with a favorable safety and tolerability profile, supporting its potential for clinical use.

Development of Composite Sponge Scaffolds Based on Carrageenan (CRG) and Cerium Oxide Nanoparticles (CeO2 NPs) for Hemostatic Applications

In this study, a novel absorbable hemostatic agent was developed using carrageenan (CRG) as a natural polymer and cerium oxide nanoparticles (CeO2 NPs). CRG-CeO2-0.5 and CRG-CeO2-1 composites were prepared by compositing CeO2 to CRG + CeO2 at a weight ratio of 0.5:100 and 1:100, respectively. The physicochemical and structural properties of these compounds were studied and compared with pristine CRG. Upon incorporation of CeO2 nanoparticles into the CRG matrix, significant reductions in hydrogel degradation were observed. In addition, it was noted that CRG-CeO2 exhibited better antibacterial and hemostatic properties than CRG hydrogel without CeO2 NPs. The biocompatibility of the materials was tested using the NIH 3T3 cell line, and all samples were found to be nontoxic. Particularly, CRG-CeO2-1 demonstrated superior hemostatic effects, biocompatibility, and a lower degradation rate since more CeO2 NPs were present in the CRG matrix. Therefore, CRG-CeO2-1 has the potential to be used as a hemostatic agent and wound dressing.

In vivo Hemostatic Activity of Jatropha mollissima: A Triple-Blinded, Randomized, Controlled Trial in an Animal Model

Objective The objective of this study was to evaluate the hemostatic activity of the sap from Jatropha mollissima (Pohl) Baill. in rats.

Materials and Methods Twenty-four Wistar rats were randomized into four groups ( n = 6): the JM25 and JM40 groups were treated with ethanolic extract from the sap of J. mollissima , in a concentration of 25 and 40 mg·mL ¹ , respectively; the MO group was treated with Monsel’s solution and the control group SC with a 0.9% sodium chloride solution.

Statistical Analysis Data were submitted to the Kurskal–Wallis’ test, followed by Dunn’s post hoc ( p < 0.05).

Results There was a significant reduction in the bleeding time of the group from the JM25 extract ( p = 0.001) when compared with MO and SC. There were no statistically significant differences between groups JM25 and JM40 ( p > 0.05). The JM25 group did not present rebleeding, a result significantly different from the MO group ( p = 0.001). Monsel’s solution showed significant bleeding, six times greater than the control group SC.

Conclusion The J. mollissima extract, in the concentration of 25 mg·mL ¹ , showed the highest hemostatic efficiency and was found to be a promising biomaterial for the elaboration of a hemostatic product.

A novel hemostat and antibacterial nanofibrous scaffold based on poly(vinyl alcohol)/poly(lactic acid)

Today, an advanced wound dressing with the ability of blood clotting and antibacterial activity is the main subject of many studies to consider their necessity in modern society. In this study, it was aimed to present a novel scaffold with both abilities simultaneously. Poly(vinyl alcohol)/poly(lactic acid) nanofibrous scaffolds containing ceftriaxone antimicrobial agent (PVA-CTX/PLA) and tranexamic acid coagulant (PVA-CTX-TXA/PLA) were fabricated by electrospinning method. Morphology, antimicrobial activity, blood coagulation and bioavailability indexes, and swelling ability (gel formation) of produced samples were determined. Morphological results showed that the hybrid nanofibers were form successfully. The antibacterial efficiency of them against Gram-negative ( Escherichia coli) and Gram-positive ( Staphylococcus aureus) bacteria was more than 90% for PVA-CTX/PLA and it reached 100% for PVA-CTX-TXA/PLA. Both PVA-CTX-TXA/PLA and PVA-TXA/PLA scaffolds showed acceptable blood coagulation ability with an average absorption of 0.043 and 0.036 nm, respectively. PVA-CTX-TXA/PLA scaffolds had a gel formation ability of about 45 min. All scaffolds were successful in cell proliferation (L929 fibroblast cell) after 48 h.