Effect of a chitosan-based hemostatic dressing on blood loss and survival in a model of severe venous hemorrhage and hepatic injury in swine

The Combination of Chitosan-Based Biomaterial and Cellular Therapy for Successful Treatment of Diabetic Foot-Pilot Study

Diabetic foot ulceration is one of the most common complications in patients treated for diabetes mellitus. The presented pilot study describes the successful treatment of diabetic ulceration of the heel with ongoing osteomyelitis in a 39-year-old patient after using a combination of modified chitosan-based biomaterial in combination with autologous mesenchymal stem cells isolated from bone marrow and dermal fibroblasts. The isolated population of bone marrow mesenchymal stem cells fulfilled all of the attributes given by the International Society for Stem Cell Research, such as fibroblast-like morphology, the high expression of positive surface markers (CD29: 99.1 ± 0.4%; CD44: 99.8 ± 0.2% and CD90: 98.0 ± 0.6%) and the ability to undergo multilineage differentiation. Likewise, the population of dermal fibroblasts showed high positivity for the widely accepted markers collagen I, collagen III and vimentin, which was confirmed by immunocytochemical staining. Moreover, we were able to describe newly formed blood vessels shown by angio CT and almost complete closure of the skin defect after 8 months of the treatment.

Granular Hemostatic Composite of Alginate, Calcium, and Zinc for Rapid and Effective Management of Post-Traumatic Hemorrhage

Post-traumatic hemorrhage, which can result from accidents or battlefield injuries, is a significant global concern due to the high prehospital mortality rate. Substantial efforts have been made to develop hemostatic agents that can effectively reduce hemorrhage in the immediate aftermath of a traumatic event. The present study investigated the potential efficacy of Ca2+ and Zn2+ supplemented sodium alginate-based dry hemostatic particles (SA-CZ DHP) to manage excessive blood loss or post-traumatic hemorrhage. SA-CZ DHP were developed, followed by their physical and biochemical characterization, cytocompatibility and hemocompatibility testing, and critical evaluation of the hemostatic potential in vitro and in vivo. The safe SA-CZ DHP showed high absorption and accelerated blood clotting kinetics with reduced coagulation time (≈70%, p < 0.0001) in whole human blood, observed with insignificant hemolysis and uninterrupted RBC morphology. SA-CZ DHP significantly reduced the mean blood loss (≈90% in SD rats tail incision), and bleeding time (≈60% in BALB/c mice tail incision) was at par with commercially available Celox hemostatic granules. In conclusion, the biocompatible SA-CZ DHP exhibited rapid and effective management of excessive blood loss. It is also pertinent to note that the developed formulation could be a cost-effective alternative to its commercial counterparts.

Evaluation of the Feasibility of Using Commercial Wound Coatings as a Carrier Matrix for Bacteriophages

The aim of the investigation is to study the possibility of applying commercial wound coatings for treating infected wounds as a carrier matrix for bacteriophages.

Materials and Methods

Twelve varieties of commercial wound coverings based on biopolymers of natural and synthetic origin, a biological preparation Staphylophag produced by scientific-industrial association Microgen (Russia), registration certificate P N001973/01, and the S. aureus 3196 test strain (GenBank JARQZO000000000) isolated from a patient with a burn wound have been used in our work. The ability of commercial biological wound coatings to absorb solutions was examined by immersing them in a physiological solution (pH 7.0-7.2) followed by weighing. The lytic activity of three bacteriophage series against the test strain was studied using the Appelman method and a spot test. The lytic activity of the bacteriophage in the wound samples was studied within 7 days after its absorption by the wound coatings.

Results

The greatest volume of fluid was absorbed by the LycoSorb, NEOFIX FibroSorb Ag, Biatravm, and Chitocol-S wound coatings. All bacteriophage series have been found to have a high lytic activity against the test strain. It has also been shown that Chitocol-S, Collachit-FA, Algipran, and Aquacel Ag Extra possessed their own inherent antibacterial activity under in vitro conditions stable for 7 days; moreover, the lysis zones of the test strain increased after their saturation with bacteriophage. On day 0, a high level of bacteriophage lytic activity with the maximum size of the test strain lysis zones from 49 to 59 mm have been found to remain in all samples of the wound coverings. The bacteriophage activity persisted for 1 day in the samples of Hydrofilm, Polypran, and NEOFIX FibroCold Ag coatings, up to 4 days in Algipran, Nano-Aseptica, and Biatravm coatings; and for 7 days in the Chitocol-S, Collachit-FA, Opsite Post-Op Visible, NEOFIX FibroSorb Ag, Aquacel Ag Extra, and LycoSorb samples.

Conclusion

Modern commercial wound dressings based on chitosan-collagen complex (Chitocol-S, Collachit-FA), polyurethane (Opsite Post-Op Visible, LycoSorb, NEOFIX FibroSorb Ag), and Hydrofiber (Aquacel Ag Extra) have a sufficient level of bacteriophage solution absorption, provide a stable preservation of the bacteriophage lytic activity under in vitro conditions up to 7 days. Thus, the in vitro studies prove the possibility of their use as a carrier matrix for bacteriophages.

An architecturally rational hemostat for rapid stopping of massive bleeding on anticoagulation therapy

Hemostatic devices are critical for managing emergent severe bleeding. With the increased use of anticoagulant therapy, there is a need for next-generation hemostats. We rationalized that a hemostat with an architecture designed to increase contact with blood, and engineered from a material that activates a distinct and undrugged coagulation pathway can address the emerging need. Inspired by lung alveolar architecture, here, we describe the engineering of a next-generation single-phase chitosan hemostat with a tortuous spherical microporous design that enables rapid blood absorption and concentrated platelets and fibrin microthrombi in localized regions, a phenomenon less observed with other classical hemostats without structural optimization. The interaction between blood components and the porous hemostat was further amplified based on the charged surface of chitosan. Contrary to the dogma that chitosan does not directly affect physiological clotting mechanism, the hemostat induced coagulation via a direct activation of platelet Toll-like receptor 2. Our engineered porous hemostat effectively stopped the bleeding from murine liver wounds, swine liver and carotid artery injuries, and the human radial artery puncture site within a few minutes with significantly reduced blood loss, even under the anticoagulant treatment. The integration of engineering design principles with an understanding of the molecular mechanisms can lead to hemostats with improved functions to address emerging medical needs.

Application of Chitosan-Based Hydrogel in Promoting Wound Healing: A Review

Chitosan is a linear polyelectrolyte with active hydroxyl and amino groups that can be made into chitosan-based hydrogels by different cross-linking methods. Chitosan-based hydrogels also have a three-dimensional network of hydrogels, which can accommodate a large number of aqueous solvents and biofluids. CS, as an ideal drug-carrying material, can effectively encapsulate and protect drugs and has the advantages of being nontoxic, biocompatible, and biodegradable. These advantages make it an ideal material for the preparation of functional hydrogels that can act as wound dressings for skin injuries. This review reports the role of chitosan-based hydrogels in promoting skin repair in the context of the mechanisms involved in skin injury repair. Chitosan-based hydrogels were found to promote skin repair at different process stages. Various functional chitosan-based hydrogels are also discussed.

In vitro analysis of tantalum-containing mesoporous bioactive glass fibres for haemostasis

Haemorrhage is the leading cause of battlefield deaths and second most common cause for civilian mortality worldwide. Biomaterials-based haemostatic agents are used to aid in bleeding stoppage; mesoporous bioactive glasses (MBGs) are candidates for haemostasis. Previously made Tantalum-containing MBG (Ta-MBG) powders' compositions were fabricated as electrospun fibres for haemostatic applications in the present study. The fibres were fabricated to address the challenges associated with the powder form: difficult to compress without gauze, getting washed away in profuse bleeding, generating dust in the surgical environment, and forming thick callus-difficult to remove for surgeons and painful for patients. Ta-MBGs were based on (80-x)SiO2-15CaO-5P2O5-xTa2O5 mol% compositions with x = 0 (0Ta), 0.5 (0.5Ta), 1 (1Ta), and 5 (5Ta) mol%. The present study details the fibres' in vitro analyses, elucidating their cytotoxic effects, and haemostatic capabilities and relating these observations to fibre chemistry and previously fabricated powders of the same glasses. As expected, when Ta addition is increased at the expense of silica, a new FTIR peak (non-bridging oxygen-silicon, Si-NBO) develops and Si-O-Si peaks become wider. Compared to 0Ta and 1Ta fibres, 0.5Ta show Si-O peaks with reduced intensity. The fibres had a weaker intensity of Si-NBO peaks and release fewer ions than powders. A reduced ion profile provides fibres with a stable matrix for clot formation. The ion release profile for 1Ta and 5Ta fibres was significantly lower than 0Ta and 0.5Ta fibres. Ta-MBGs were not found to be cytotoxic to primary rat fibroblasts using a methyl thiazolyl tetrazolium (MTT) assay. Furthermore, a modified activated partial thromboplastin time assay analysing the fibrin absorbance showed that the absorption increases from physiological clotting < 0Ta < 0.5Ta < 5Ta < commercial haemostat, Surgical SNoWTM, Ethicon, USA < 1Ta. Higher absorption signifies a stronger clot. It is concluded that Ta-MBG fibres can provide stable matrix for clot formation and 1Ta can potentially enhance clotting best among other Ta-MBGs.

Characterization and Analysis of Chitosan-Gelatin Composite-Based Biomaterial Effectivity as Local Hemostatic Agent: A Systematic Review

Chitosan and gelatin were the most widely used natural materials in pharmaceutical and medical fields, especially as local hemostatic agents, independently or as a composite material with the addition of other active substances. Chitosan and gelatin have excellent properties in biocompatibility, biodegradability, non-toxicity and water absorption capacity. The objective of this review was to analyze the characteristics of chitosan-gelatin (CG) composite-based biomaterial and its effectivity as a local hemostatic agent. We used PRISMA guidelines and the PICO framework to compile this review. The findings demonstrated that the CG composite-based biomaterial had excellent physical, chemical, mechanical properties and local hemostatic agent activity by adding other active substances such as oxidized fibers (OF), silica nanoparticles (SiNPs), calcium (Ca) and biphasic calcium phosphate (BCP) or by setting the CG composite proportion ratio.

Advances in the development and optimization strategies of the hemostatic biomaterials

Most injuries are accompanied by acute bleeding. Hemostasis is necessary to relieve pain and reduce mortality in these accidents. In recent years, the traditional hemostatic materials, including inorganic, protein-based, polysaccharide-based and synthetic materials have been widely used in the clinic. The most prominent of these are biodegradable collagen sponges (Helistat^®, United States), gelatin sponges (Ethicon^®, SURGIFOAM^®, United States), chitosan (AllaQuixTM, ChitoSAMTM, United States), cellulose (Tabotamp^®, SURGICEL^®, United States), and the newly investigated extracellular matrix gels, etc. Although these materials have excellent hemostatic properties, they also have their advantages and disadvantages. In this review, the performance characteristics, hemostatic effects, applications and hemostatic mechanisms of various biomaterials mentioned above are presented, followed by several strategies to improve hemostasis, including modification of single materials, blending of multiple materials, design of self-assembled peptides and their hybrid materials. Finally, the exploration of more novel hemostatic biomaterials and relative coagulation mechanisms will be essential for future research on hemostatic methods.

Crustacean polysaccharides for the geotechnical enhancement of organic silt: A clean and green alternative

Biopolymer-based soil stabilization offers a clean alternative to conventional stabilizers like cement and lime. This study investigates the possibility of using shrimp-based chitin and chitosan for stabilizing low plastic silt with organic content by investigating their effect on pH, compaction, strength, hydraulic conductivity (HC) and consolidation characteristics. X-ray diffraction (XRD) spectrum shows that no new chemical compounds were formed in the soil on additive treatment; however, results of scanning electron microscope (SEM) analysis indicate the formation of biopolymer threads that bridge the voids in the soil matrix leading to a stiffer soil matrix, with increased strength and lower HC. Chitosan showed nearly 103 % strength enhancement after 28 d of curing with no degradation. However, chitin failed as a soil stabilizing additive as it showed degradation owing to fungal bloom after 14 d of curing. Chitosan can therefore be recommended as a non-polluting and sustainable soil additive.

The effectiveness of portable ultrasound-guided resuscitative endovascular balloon occlusion of the aorta for stopping iliac artery hemorrhage during first aid pre-hospital: a randomized control animal trial

PURPOSE

This study aimed at to comparing the effectiveness of portable ultrasound guided REBOA vs. traditional manual extracorporeal compression in stopping iliac artery hemostasis.

METHODS

Twelve swine were included in this study (treatment group vs. control group, 6:6). A biopsy device was used to create an iliac artery rupture and hemorrhage in each swine. After 30 s of bleeding, the treatment group received REBOA under the guidance of ultrasound, whereas the control group received traditional manual extracorporeal compression. General physiological conditions were recorded at 0 s (baseline, T1), 30 s (initiation of therapies to stop bleeding, T2), 10 min (T3) and 30 min (T4) after bleeding. Intraperitoneal and retroperitoneal hemorrhage and specimens of iliac artery were collected after all swine were euthanized.

RESULTS

One swine was excluded because of accidental death not related to the experiment; thus, 11 swine were analyzed in this study. The general physiological characteristics of the two groups showed no difference at T1. Hemorrhagic shock occurred in both groups. After the hemostatic procedure was performed, systolic pressure, diastolic pressure and heart rate first increased significantly between T2 and T3, and then became stable between T3 and T4; these indicators in the control group deteriorated over time. The total blood loss in the treatment group (1245.23 ± 190.07 g) was much significantly less than that in the control group (2605.63 ± 291.67 g) with p < 0.001.

CONCLUSIONS

Performing REBOA under the guidance of portable ultrasound is an effective way to stop bleeding. It suggests a potential alternative method for iliac artery hemostasis in the pre-hospital setting.

Medical Adhesives and Their Role in Laparoscopic Surgery—A Review of Literature

Laparoscopic surgery is undergoing rapid development. Replacing the traditional method of joining cut tissues with sutures or staples could greatly simplify and speed up laparoscopic procedures. This alternative could undoubtedly be adhesives. For decades, scientists have been working on a material to bond tissues together to create the best possible conditions for tissue regeneration. The results of research on tissue adhesives achieved over the past years show comparable treatment effects to traditional methods. Tissue adhesives are a good alternative to surgical sutures in wound closure. This article is a review of the most important groups of tissue adhesives including their properties and possible applications. Recent reports on the development of biological adhesives are also discussed.

Development of a Hemostatic Urinary Catheter for Transurethral Prostatic Surgical Applications

OBJECTIVE

To investigate a novel transurethral hemostatic catheter device with an integrated chitosan endoluminal hemostatic dressing (CEHD). Development and implementation of this technology may help address bleeding following surgery such as transurethral resection of prostate (TURP). Bleeding remains the most common complication following TURP, leading to increased morbidity and hospitalization.

METHODS

Investigation of hemostasis, delivery, safety and efficacy of the CEHD device is conducted using Female Yorkshire swine (N = 23). Hemostatic efficacy of the CEHD (N = 12) is investigated against a control of gauze (N = 12) in a splenic injury model (3 swine). The delivery, safety, and efficacy of the CEHD device (N = 10) are investigated against Foley-catheter control (N = 10) for 7 days using a swine bladder-neck-injury model.

RESULTS

In the splenic injury study, 9/12 CEHD dressings successfully achieved hemostasis within 150 seconds (mean 83 seconds) vs success of 6/12 (mean 150 seconds) for gauze (P = .04). In the 7-day study, the CEHD was successfully deployed in 10/10 animals and all dressings were tolerated without histologic or clinical adverse effect. Hemostasis of the CEHD device was found to be noninferior to control catheters. Noninferiority is attributed to low bleeding rates in the swine bladder neck injury model.

CONCLUSION

This investigation successfully demonstrated the feasibility of transurethral deployment of the CEHD in vivo. Routine use of safe and slowly dissolvable CEHDs could reduce the rate of complications and hospitalizations associated with bleeding and blood loss in TURP procedures. Further investigation is warranted.

Porcine liver injury model to assess tantalum-containing bioactive glass powders for hemostasis

This study evaluates compositions of tantalum-containing mesoporous bioactive glass (Ta-MBG) powders using a porcine fatal liver injury model. The powders based on (80-x)SiO₂-15CaO-5P₂O₅-xTa₂O₅ compositions with x = 0 (0Ta/Ta-free), 1 (1Ta), and 5 (5Ta) mol% were made using a sol-gel process. A class IV hemorrhage condition was simulated on the animals; hemodynamic data and biochemical analysis confirmed the life-threatening condition. Ta-MBGs were able to stop the bleeding within 10 min of their application while the bleeds in the absence of any intervention or in the presence of a commercial agent, Arista^TM (Bard Davol Inc., Rhode Island, USA) continued for up to 45 min. Scanning electron microscopy (SEM) imaging of the blood clots showed that the presence of Ta-MBGs did not affect clot morphology. Rather, the connections seen between fibrin fibers of the blood clot and Ta-MBG powders point towards the powders' surfaces embracing fibrin. Histopathological analysis of the liver tissue showed 5Ta as the only composition reducing parenchymal hemorrhage and necrosis extent of the tissue after their application. Additionally, 5Ta was also able to form an adherent clot in worst-case scenario bleeding where no adherent clot was seen before the powder was applied. In vivo results from the present study agree with in vitro results of the previous study that 5Ta was the best Ta-MBG composition for hemostatic purposes. Graphical abstract.

A Bio-Inorganic Hybrid Hemostatic Gauze for Effective Control of Fatal Emergency Hemorrhage in "Platinum Ten Minutes"

Death from massive hemorrhage represents a global problem. It is a challenging task to design hemostatic materials with significant efficacy, good biocompatibility, reliable safety, and high stability. In this study, we demonstrate an effective bio-inorganic hybrid hemostat fabricated by stepwise procedures of on-site growth of zeolite gauze and immobilization of trypsin on the zeolite gauze. The as-synthesized hybrid hemostat catalyzes the transition of prothrombin-to-thrombin and exhibits excellent procoagulant performance in the both normal plasma and FX-deficient plasma. The hemostatic treatment of junctional femoral artery rupture in the porcine model confirms that this hybrid hemostat manifests itself with superior hemostatic performance over commercial hemostatic dressings, in terms of a reduced time to hemostasis and blood loss. The stability of the hybrid hemostat is validated through high temperature and violent shaking evaluation. This bio-inorganic hybrid hemostat displays high procoagulant activity, low cytotoxicity, and extended shelf life which may achieve the "Platinum Ten Minutes" rescue in battlefield and traffic accident medicine.

Silk Fibroin-Based Biomaterials for Hemostatic Applications

Hemostasis plays an essential role in all surgical procedures. Uncontrolled hemorrhage is the primary cause of death during surgeries, and effective blood loss control can significantly reduce mortality. For modern surgeons to select the right agent at the right time, they must understand the mechanisms of action, the effectiveness, and the possible adverse effects of each agent. Over the past decade, various hemostatic agents have grown intensely. These agents vary from absorbable topical hemostats, including collagen, gelatins, microfibrillar, and regenerated oxidized cellulose, to biologically active topical hemostats such as thrombin, biological adhesives, and other combined agents. Commercially available products have since expanded to include topical hemostats, surgical sealants, and adhesives. Silk is a natural protein consisting of fibroin and sericin. Silk fibroin (SF), derived from silkworm Bombyx mori, is a fibrous protein that has been used mostly in fashion textiles and surgical sutures. Additionally, SF has been widely applied as a potential biomaterial in several biomedical and biotechnological fields. Furthermore, SF has been employed as a hemostatic agent in several studies. In this review, we summarize the several morphologic forms of SF and the latest technological advances on the use of SF-based hemostatic agents.

Chitosan: A review of molecular structure, bioactivities and interactions with the human body and micro-organisms

Chitosan has many desirable attributes e.g. antimicrobial properties and promoting wound healing, and is used in various applications. This article first discusses how degree of deacetylation (DD) and molecular weight (MW) impacts on what level of bioactivities chitosan manifests, then introduces the "molecular chain configuration" model to explain various possible mechanisms of antimicrobial interactions between chitosan with different MW and different types of bacteria. Similarly, the possible pathways of how chitosan reacts with cancer and the body's immune system to demonstrate immune and antitumor effects are also discussed by using this model. Moreover, the possible mechanisms of how chitosan enhances coagulation and wound healing are also discussed. With these beneficial bioactivities in mind, the application of chitosan in surgery, tissue engineering and oncology is outlined. This review concludes that as chitosan demonstrates many beneficial bioactivities via multiple mechanisms, it is an important polymer with a promising future in medicine.

Efficacy and Safety of Novel Beta-Chitin Patches as Haemostat in Rat Vascular and Neurosurgical Model

Background

Intraoperative hemorrhage is a major cause of poor post-operative outcome. Beta-chitin patch has previously been found to be an effective haemostat, but whether modifying the patch can improve its efficacy and safety, remains unknown. In this study, beta-chitin patches were modified using polyethylene oxide, Pluronic-F127 (Chi/F127), calcium (Chi/20%Ca), increased thickness (Chi/Thick) or polyphosphate (Chi/PP).

Objective

Using rat (Wistar Albino; 8–10 weeks old) vascular and neurosurgical models, this project investigated and compared the efficacy and safety of beta-chitin patches with gauze, Surgicel and FloSeal.

Methods

Ninety rats underwent a standardized femoral artery injury and were randomized to receive either beta-chitin patches, gauze, Surgicel or FloSeal. The bleeding time and total blood loss was measured. For the neurosurgical model, forty-four rats underwent a standardized cortical injury and randomization to a treatment group. Following a 48 h recovery period, their brains were collected for histopathological examination.

Results

The mean bleeding time with Chitin (120.8 s) and Chi/PP (117.3 s) was ~60 s lower than Chi/F127, Chi/20%Ca and Chi/Thick (p &lt; 0.05). Chitin and Chi/PP had a significantly lower bleeding time than FloSeal (174.2 s) (p &lt; 0.05), but not Surgicel (172.7 s). Gauze (400 s) had a significantly higher bleeding time compared to all other groups (p &lt; 0.05). There were no significant differences in the total blood loss between the groups. Histopathological examination of brains found no adverse inflammatory reaction to any of the haemostatic compounds.

Conclusion

Chi/PP had superior haemostatic efficacy compared to Surgicel and FloSeal, but not compared to non-modified beta-chitin patch. All of the haemostats were equally safe.

Advanced bioactive nanomaterials for biomedical applications

Bioactive materials are a kind of materials with unique bioactivities, which can change the cellular behaviors and elicit biological responses from living tissues. Bioactive materials came into the spotlight in the late 1960s when the researchers found that the materials such as bioglass could react with surrounding bone tissue for bone regeneration. In the following decades, advances in nanotechnology brought the new development opportunities to bioactive nanomaterials. Bioactive nanomaterials are not a simple miniaturization of macroscopic materials. They exhibit unique bioactivities due to their nanoscale size effect, high specific surface area, and precise nanostructure, which can significantly influence the interactions with biological systems. Nowadays, bioactive nanomaterials have represented an important and exciting area of research. Current and future applications ensure that bioactive nanomaterials have a high academic and clinical importance. This review summaries the recent advances in the field of bioactive nanomaterials, and evaluate the influence factors of bioactivities. Then, a range of bioactive nanomaterials and their potential biomedical applications are discussed. Furthermore, the limitations, challenges, and future opportunities of bioactive nanomaterials are also discussed.

Harnessing Multifaceted Next-Generation Technologies for Improved Skin Wound Healing

Dysregulation of sequential and synchronized events of skin regeneration often results in the impairment of chronic wounds. Conventional wound dressings fail to trigger the normal healing mechanism owing to the pathophysiological conditions. Tissue engineering approaches that deal with the fabrication of dressings using various biomaterials, growth factors, and stem cells have shown accelerated healing outcomes. However, most of these technologies are associated with difficulties in scalability and cost-effectiveness of the products. In this review, we survey the latest developments in wound healing strategies that have recently emerged through the multidisciplinary approaches of bioengineering, nanotechnology, 3D bioprinting, and similar cutting-edge technologies to overcome the limitations of conventional therapies. We also focus on the potential of wearable technology that supports complete monitoring of the changes occurring in the wound microenvironment. In addition, we review the role of advanced devices that can precisely enable the delivery of nanotherapeutics, oligonucleotides, and external stimuli in a controlled manner. These technological advancements offer the opportunity to actively influence the regeneration process to benefit the treatment regime further. Finally, the clinical relevance, trajectory, and prospects of this field have been discussed in brief that highlights their potential in providing a beneficial wound care solution at an affordable cost.

Multi-Scale Photoacoustic Assessment of Wound Healing Using Chitosan-Graphene Oxide Hemostatic Sponge

Hemostasis is vital to save lives, reducing risks of organ failure and hemorrhagic shock. Exploring novel hemostatic materials and precise monitoring of the hemostatic status is of great importance for efficient hemostasis. We present the development of chitosan-graphene oxide-based hemostatic composite and multi-scale photoacoustic evaluation of the hemostatic performance. The hemostatic sponge can quickly and efficiently absorb the blood with its porous cavity and specific surficial property. We inspect the hemostatic performance via an in vitro blood absorption test and in vivo mouse bleeding injury experiments. Results show that the synthesized hemostatic sponge can not only absorb plasma in blood fast with its interior porous structure but also stimulate the interfacial reaction with erythrocytes and platelets. The superiority of multi-scale photoacoustic imaging for guiding, monitoring, and evaluating the hemostatic stages of sponges is demonstrated with high spatial resolution and great sensitivity at depths. Photoacoustic evaluation of a chitosan-graphene oxide-based hemostatic sponge has the potential to be transferred toward the clinical assessment of wound healing.

Robust hemostatic bandages based on nanoclay electrospun membranes

Death from acute hemorrhage is a major problem in military conflicts, traffic accidents, and surgical procedures, et al. Achieving rapid effective hemostasis for pre-hospital care is essential to save lives in massive bleeding. An ideal hemostasis material should have those features such as safe, efficient, convenient, economical, which remains challenging and most of them cannot be achieved at the same time. In this work, we report a rapid effective nanoclay-based hemostatic membranes with nanoclay particles incorporate into polyvinylpyrrolidone (PVP) electrospun fibers. The nanoclay electrospun membrane (NEM) with 60 wt% kaolinite (KEM1.5) shows better and faster hemostatic performance in vitro and in vivo with good biocompatibility compared with most other NEMs and clay-based hemostats, benefiting from its enriched hemostatic functional sites, robust fluffy framework, and hydrophilic surface. The robust hemostatic bandages based on nanoclay electrospun membrane is an effective candidate hemostat in practical application.

Rapid, easy and effective haemostasis is needed to reduce the loss of life from traumatic haemorrhage. Here, the authors report on the creation of polymer-nanoclay electrospun membranes and demonstrate haemostatic effects showing superior effects to other clay based haemostats.

Chitosan-microencapsulated rhEGF in promoting wound healing

AIMS

Chitosan and epidermal growth factor (EGF) have been shown to improve wound healing. This study investigates the healing effects of a spray solution (NewEpi, JoyCom Bio-Chem Co. Ltd., Taiwan) containing recombinant human EGF (rhEGF) delivered via a newly patented technology-chitosan microencapsulated nanoparticles.

METHODS

On Wistar rats, two full-thickness wounds on the dorsum bilateral of the spine were created. The rats were randomised to the following treatment groups: hydrogel, wet dressing, foam, rhEGF spray and rhEGF spray+foam. Sterile dressings were applied and changed daily. A total of 2μg of rhEGF was administered in two sprays during each dressing change. All animals were euthanised on day 14. Tissue samples were taken from the wound bed, including an area of 2cm surrounding the wound margin for histological evaluations.

RESULTS

Wounds treated with the rhEGF spray achieved the greatest size reduction by day 14 compared with other types of conventional dressings. An overall significant difference in levels of collagen synthesis existed between groups (p<0.01). Pair-wise comparisons showed that the rhEGF spray treatment significantly promoted higher levels of mature Type I collagen than any other conventional dressings (p<0.01), whereas non-rhEGF treatments resulted in higher levels of Type III collagen. The regenerated tissue in rhEGF spray treatment groups was also in alignment with that of normal skin. Epidermis, dermis and hair follicles were easily observed in wounds treated with the rhEGF spray.

CONCLUSION

The major challenge of topical application of rhEGF was overcome by using a new drug delivery technology: chitosan-rhEGF nanoparticles. The positive healing effects observed in this study suggest the therapeutic potentials of this novel rhEGF topical spray solution.

Effect of platelet-rich fibrin versus chitosan-based Axiostat hemostatic agent following dental extraction in cardiac patients on antiplatelet therapy: A comparative study

Background:

Platelet-rich fibrin (PRF) is a biomaterial that promotes wound healing. It has a fibrinous matrix wherein platelets, pro-inflammatory cytokines, and various growth factors along with few cells are entrapped while Chitosan is a naturally occurring cationic biopolymeric material that is derived from an animal product, chitin. It has demonstrated biological properties which include acceleration in wound healing, hemostasis, enhancement of immunological response, mucosal adhesion by eliciting biological responses, and anti-microbial action.

Aim:

The aim of this study was to evaluate the effect of PRF and Axiostat (A chitosan-based product) on hemostasis after tooth extraction among cardiac patients on antiplatelet medication.

Materials and Methods:

This prospective study was carried out on 300 patients undergoing tooth extraction. Participants were divided into two categories (n = 150, respectively) as Group I (PRF dressing) and Group II (Axiostat dressing). Time to achieve hemostasis was observed using a stopwatch. Average pain score calculation was performed using visual analog on the 7-day postoperative period. Descriptive statistics were done, and data analysis was performed using the Mann–Whitney U-test. P < 0.5 and < 0.001 were considered statistically significant and extremely significant, respectively.

Results:

Average pain score was 1.86 ± 0.06 in Group I and 1.05 ± 0.87 in Group II. Thus, lower postoperative pain was seen with Axiostat dressing. Hemostasis was achieved in Group II participants in 1.25 ± 0.06 min and in 1.89 ± 0.54 min in Group I. P < 0.01 was obtained, although no statistically significant difference in postoperative pain scores (P = 0.8) was seen.

Conclusion:

Chitosan is a superior wound dressing material in achieving hemostasis in cardiac patients on antiplatelet medication after tooth extraction.

Hemostatic performance of chitosan-based hydrogel and its study on biodistribution and biodegradability in rats

Hemostasis is of great significance regardless of the smooth operation or postoperative recovery. Therefore, it is urgent to develop a hemostatic material with excellent biodegradability and biocompatibility. It is well known that both carboxymethyl chitosan and hyaluronic acid with biodegradability and biocompatibility have wound healing promoting property. Here, a degradable chitosan-based hydrogel was prepared based on carboxymethyl chitosan and cross-linked by oxidized hyaluronic acid. The hemostatic performance of the hydrogel in rat liver resection injury was evaluated which results showed that the hydrogel exhibited comparable hemostatic properties compared with Fibrin Sealant. In addition, the hydrogel proved to be rapidly absorbed by the body without significant accumulation in vivo, demonstrating good biodegradability and biocompatibility. The overall results suggested the hydrogel will be a promising hemostatic hydrogel for controlling bleeding.

Intermolecular interactions of chitosan: Degree of acetylation and molecular weight

The degree of acetylation (DA), which determines as the molar proportion of N-acetyl-D-glucosamine units on chitosan, characterizes the physical, chemical, and biological properties of chitosan. Thus, DA can be a critical factor in the utilization of chitosan. Nevertheless, quantitative studies on the molecular interactions of chitosan as a function of DA are lacking. Here, we directly measured the molecular interaction (adhesion and cohesion) of molecularly thin chitosan films, dependent on the molecular weight and DA, using a surface forces apparatus. Using low molecular weight (LMW, ∼5 kDa) and high molecular weight (HMW, ∼135 kDa) chitosan, we obtained several DA ranges through a reacetylation method. The interactions of LMW chitosan were greatly influenced by the intrinsic charge of the chitosan units, whereas for HMW chitosan, chain flexibility was found to be the major factor affecting molecular interaction Taken together, our comprehensive data provides a holistic understanding of the interaction mechanism of chitosan.

Vasoconstrictor and coagulation activator entrapped chitosan based composite hydrogel for rapid bleeding control

Chitosan (Cs) as a hemostatic agent has been in use to control hemorrage. Composite hydrogel formed by entrapment of vasoconstrictor-potassium aluminium sulfate (0.25 %PA) and coagulation activator-calcium chloride (0.25 %Ca) into Cs (2 %) hydrogel would enhance the hemostatic property of Cs. In this work, the prepared composite hydrogel was injectable, shear thinning, cyto and hemocompatible. The 2 %Cs-0.25 %PA-0.25 %Ca composite hydrogel caused rapid blood clotting by accelerating RBC/platelet aggregation and activation of the coagulation cascade. Further, in vivo studies on rat liver and femoral artery hemorrage model showed the efficiency of 2 %Cs-0.25 %PA-0.25 %Ca composite hydrogel to achieve hemostasis in a shorter time (20 ± 10 s, 105 ± 31 s) than commercial hemostatic agents-Fibrin sealant (77 ± 26 s, 204 ± 58 s) and Floseal (76 ± 15 s, 218 ± 46 s). In in vivo toxicological study, composite hydrogel showed material retention even after 8 weeks post-surgery, therefore excess hydrogel should be irrigated from site of application. This prepared composite hydrogel based hemostatic agent has potential application in low pressure bleeding sites.

A Review: Uses of Chitosan in Pharmaceutical Forms

Chitosan is a natural polysaccharide widespread in nature. It has many unique and attractive properties for the pharmaceutical field: it is biodegradable, safe, hypoallergenic, biocompatible with the body, free of toxicity, with proven anticholesterolemic, antibacterial, and antimycotic action. In this review we highlighted the physical, chemical, mechanical, mucoadhesive, etc. properties of chitosan to be taken into account when obtaining various pharmaceutical forms. The methods by which the pharmaceutical forms based on chitosan are obtained are very extensive, and in this study only the most common ones were presented.

A glimpse on the function of chitosan as a dental hemostatic agent

Managing a bleeding patient can be a challenge during dental surgery. Profuse hemorrhage due to platelet defects, coagulation disorders, vascular anomalies, medication-induced patients, as well as inherited bleeding ailments result in soft tissue hematoma, septic shock, compromised airway, and in some severe cases, death could occur. A vast array of surgical hemostatic agents are available to stop bleeding, including chitosan-based hemostatic agents. Chitosan has an advantage over other topical hemostatic materials for its ability to promote shorter bleeding times and assist in healing. Massive behind-the-scene research and development efforts are ongoing to increase the performance of chitosan as a hemostatic agent. Numerous studies on chitosan use in dental hemostasis have registered it as being safe, biodegradable, biocompatible, promoting healing, antimicrobial and bioactive. This article reviews the application of chitosan in managing hemostasis in dental patients.

Efficacy of alginate-and chitosan-based scaffolds on the healing of diabetic skin wounds in animal experimental models and cell studies: A systematic review

This systematic literature review was aimed to investigate the use of cell culture and animal models to evaluate the efficacy of alginate-and chitosan-based scaffolds on diabetic wound healing. We electronically searched the articles published until July 2019. The databases included five English databases such as PubMed, Web of Science, Embase, the Cochrane Library, CINAHL, and three Chinese databases like CNKI, WanFang Data, and VIP. The related articles were manually searched to identify studies that were not searched by electronic database searches. Twenty-nine studies met the inclusion criteria. We divided the results into three groups: chitosan, alginate, and a combination of chitosan and alginate. Chitosan-, alginate-, and a combination of chitosan and alginate-based scaffolds showed good intervention effects on wound healing. Chitosan-based scaffolds were effective in diabetic skin wound healing. The effects of alginate and the combination of chitosan-and alginate-based scaffolds on diabetic skin wounds still need more research. However, due to the heterogeneity of animal and cell preclinical trials and the validity of the statistical analysis used in these studies, it is necessary to conduct a thorough study using well-designed experiments to confirm these results. In addition, properly designed chitosan-and/or alginate-based scaffolds with thorough preclinical evaluations are required prior to clinical applications.

Alginate-based composite microspheres coated by berberine simultaneously improve hemostatic and antibacterial efficacy

It is important to develop effective, biocompatible, easily stored and affordable hemostats for controlling bleeding and preventing infection in prehospital trauma. In this study, we synthesized a series of alginate-based composite microspheres coated by different amounts of berberine (SCC-1B, SCC-5B and SCC-10B), which were further characterized using scanning electron microscopy (SEM), viscometer, particle analyzer and Fourier transform infrared (FT-IR) spectroscopy. The in vitro and vivo results demonstrated that compared to control group (SCC, Composite polysaccharide microspheres without berberine, and CMPHP, Commercial hemostatic agent), SCC-10B with proper content berberine (7%), not only exhibited inherent excellent antibacterial activity, but also enhanced hemostatic effect by increasing adhesion and aggregation of blood cells, which could be considered as synergistic effects. More importantly, through inserting berberine into the cross-linked network, biodegradability and biocompatibility of SCC-10B were also improved. Taken together, SCC-10B could be a candidate for emergency hemostatic and antibacterial treatment in prehospital trauma.

Gellable silk fibroin-polyethylene sponge for hemostasis

Traditional haemostatic materials generally have slow hemostasis rate and poor biocompatibility. This paper reports on the haemostatic properties and mechanism of silk fibroin (SF). SF-PEG sponge that could be solubilised and changed to gel form by blood was fabricated through mixing SF and polyethylene glycol (PEG, 1500 Da) followed by lyophilisation of the mixed solution. SF-PEG sponge, together with control samples of SF sponge (no PEG) and a commercially available haemostatic material, gelatine sponge, were subjected to the hemostasis tests using a liver trauma model of rabbit. The results showed that SF was superior to gelatine sponge in hemostasis time (136.17 ± 62.27 s and 249.83 ± 29.18 s) and blood loss (2.16 ± 1.27 g vs. 4.97 ± 1.44 g). Furthermore, in vitro experiments indicated SF-PEG sol-gel transition promoted platelet adhesion and aggregation, as well as platelet-fibrinogen interaction. Therefore, except for the physical blocking of bleeding port due to PEG-induced SF fast gelation, SF might also have an impact on blood coagulation process, a phenomenon that has not been reported before. In conclusion, SF is a new type of haemostatic material that might be able to meet the requirements of speed, efficiency and biosafety in a variety of clinical applications.

The Antimicrobial Effectiveness and Cytotoxicity of the Antibiotic-Loaded Chitosan: ECM Scaffolds

Background: The development of multifunctional wound dressings with the ability to control hemostasis, limit infection and promote rapid wound healing and constructive tissue remodeling has been a challenge for many years. In view of these challenges, a hybrid scaffold platform was developed that combined two different extracellular matrices (ECM): ECM from decellularized mammalian tissue and ECM (chitosan) from crustaceans. Both types of ECM have well established clinical benefits that support and promote wound healing and control hemostasis. This scaffold platform could also be augmented with antibiotics to provide bactericidal activity directly to the wound site. Methods: Four different scaffold formulations were developed containing chitosan supplemented with either 20% or 50% urinary bladder matrix (UBM) hydrogel or 1% (w/v) or 10% (w/v) UBM–ECM particulates. 100% chitosan scaffolds were used as controls. The scaffolds were augmented with either minocycline or rifampicin. Escherichia Coli and Staphylococcus Aureus were used to assesses antimicrobial efficacy and duration of activity, while neutral red uptake assays were performed to establish direct and indirect cytotoxicity. Results: Results showed that scaffold handling properties, scaffold integrity over time and the efficacy and release rate of loaded antibiotics could be modified by altering scaffold composition. Moreover, antibiotics were easily released from the scaffold and could remain effective for up to 24 h by modifying the scaffold composition. Variable results with cytotoxicity testing show that further work is required to optimize the scaffold formulations but these proof of principle experiments suggest that these scaffolds have potential as bioactive wound dressings.

Recent Advances in Hemostasis at the Nanoscale

Rapid and effective hemostatic materials have received wide attention not only in the battlefield but also in hospitals and clinics. Traditional hemostasis relies on materials with little designability which has many limitations. Nanohemostasis has been proposed since the use of peptides in hemostasis. Nanomaterials exhibit excellent adhesion, versatility, and designability compared to traditional materials, laying a good foundation for future hemostatic materials. This review first summarizes current hemostatic methods and materials, and then introduces several cutting-edge designs and applications of nanohemostatic materials such as polypeptide assembly, electrospinning of cyanoacrylate, and nanochitosan. Particularly, their advantages and working mechanisms are introduced. Finally, the challenges and prospects of nanohemostasis are discussed.

A review of the application of cellulose hemostatic agent on trauma injuries

Introduction

Planning for management of bleeding in trauma injuries is very important. The initial purpose in emergency situations should be immediate establishment of an efficient hemostasis, principally in its topical application. In this study, we aimed to review the major relevant articles in the case of application of cellulose hemostatic agent on trauma injuries.

Methods

We searched the online databases such as PubMed, MEDLINE, Wiley, EMBASE, ISI Web of Knowledge, and Scopus. Two reviewers independently searched and assessed the titles and abstracts of all articles.

Results

Upon screening the titles and abstracts, 24 studies were identified for full-text review. The oxidized cellulose had the best clotting times, while it demonstrated low absorption ability. Surgical and thermosensitive chitosan hemostatic could be valuable for managing hemorrhage from liver injuries in trauma patients.

Conclusion

Recently, the application of cellulose hemostatic agents has been one of the main improvements obtained for controlling bleeding in trauma injuries. However, generally according to the literature review, the decision about using each agent should be made on a case-by-case basis. However, it can be mentioned that the perfect hemostatic agent has not been still identified.

The Effects of Various Hemostatic Agents on Shear-bond Strength in Primary Teeth: An In Vitro Study

Aims and objectives:

The aim of this study was to determine the effects of chitosan, Ankaferd Blood Stopper® (ABS, Ankaferd Health Products Ltd, Turkey), and ferric sulfate (FS) on the shear-bond strength of the self-etch adhesive to primary tooth dentin.

Materials and methods:

The occlusal surfaces of 80 extracted human primary teeth (stored in a 0.5% chloramine-T solution at 4oC) were ground flat, exposing the dentin. The teeth were divided into 4 groups: chitosan, ABS, FS, and control. Hemostatic agents were applied to the teeth, and then they were rinsed with distilled water and air dried. In the control group, the teeth were only rinsed with distilled water and slightly air dried. A self-etch adhesive was applied, and the composite cylinder was created on all the samples. Shear-bond strength was tested with a universal testing machine. Failure mode analysis was performed using scanning electron microscopy.

Results:

The study revealed no statistically significant difference between the hemostatic agent and control groups in terms of bond strength ( P >.05). The highest bond strength was observed in the chitosan group. In this group, a statistically significant difference between chitosan and ABS was observed ( P <.05). The adhesive failure was the predominant failure mode in all the groups.

Conclusions:

These findings suggest that chitosan, ABS, and FS have no adverse effects on the bonding of the self-etch adhesive to primary teeth dentin.

Systematic review of prehospital haemostatic dressings

Introduction

Haemorrhage is one of the leading causes of battlefield and prehospital death. Haemostatic dressings are an effective method of limiting the extent of bleeding and are used by military forces extensively. A systematic review was conducted with the aim of collating the evidence on current haemostatic products and to assess whether one product was more effective than others.

Methods

A systematic search and assessment of the literature was conducted using 13 health research databases including MEDLINE and CINAHL, and a grey literature search. Two assessors independently screened the studies for eligibility and quality. English language studies using current-generation haemostatic dressings were included. Surgical studies, studies that did not include survival, initial haemostasis or rebleeding and those investigating products without prehospital potential were excluded.

Results

232 studies were initially found and, after applying exclusion criteria, 42 were included in the review. These studies included 31 animal studies and 11 clinical studies. The outcomes assessed were subject survival, initial haemostasis and rebleeding. A number of products were shown to be effective in stopping haemorrhage, with Celox, QuikClot Combat Gauze and HemCon being the most commonly used, and with no demonstrable difference in effectiveness.

Conclusions

There was a lack of high-quality clinical evidence with the majority of studies being conducted using a swine haemorrhage model. Iterations of three haemostatic dressings, Celox, HemCon and QuikClot, dominated the studies, probably because of their use by international military forces and all were shown to be effective in the arrest of haemorrhage.

Prospective Randomized Controlled Study of Hemostatic Efficacy with Kaolin-Impregnated Dressings in Diabetic Foot Ulcers Taking Anticoagulants Undergoing Debridement in an Outpatient Clinic

BACKGROUND

The effective hemostasis after minor debridement in an outpatient clinic is important and essential. This study is aimed at evaluating the hemostatic efficacy and safety of the kaolin-impregnated dressing for diabetic foot ulcer patient who take an anticoagulant.

METHODS

A prospective, randomized, clinical trial study was performed in twenty-six patients with diabetic foot ulcers who take an anticoagulant requiring minor debridement in an outpatient clinic. Minor debridement and removal of break down skin were performed by one orthopedic surgeon. Hemostasis on wound bed was achieved using kaolin-impregnated gauze (study group) and standard sterilized dry gauze (control group). Two randomized groups were compared for hemostatic efficacy and side effect.

RESULTS

For the purpose of this study, the presence or absence of hemostasis was assessed at 5 and 10 minutes after the application of dressing material. Treatment was evaluated as successful if bleeding was ceased adequately, and no extra hemostatic measures were required within 10 minutes. At 5 minutes, 80% of patients using the kaolin-impregnated gauze successfully achieved complete hemostasis versus 40% in the control group that controlled bleeding partially. With kaolin-impregnated gauze, 100% of patients show complete hemostasis at 10 minutes versus 58.3% in the standard gauze (P < .001). An adverse effect was not noted in all patients.

CONCLUSIONS

The use of kaolin-impregnated gauze appears to be a safe and feasible option in managing bleeding after debridement of diabetic foot ulcers, and merits to patient who had a bleeding tendency is high. This trial is registered with CRIS registration number KCT0003894.

Nanotechnology-enabled materials for hemostatic and anti-infection treatments in orthopedic surgery

The hemostatic and anti-infection treatments in the field of orthopedics are always the pivotal yet challenging topics. In the first part of this review, synthesized or naturally derived nanoscale agents and materials for hemostatic treatment in orthopedic surgery are introduced. The hemostatic mechanisms and the safety concerns of these nanotechnology-enabled materials are discussed. Beside the materials to meet hemostatic needs in orthopedic surgery, the need for antimicrobial or anti-infection strategy in orthopedic surgery also becomes urgent. Nanosilver and its derivatives have the most consistent anti-infective effect and thus high translational potential for clinical applications. In the second part, the factors affecting the antimicrobial effect of nanosilver and its application status are summarized. Finally, the status and translational potential of various nanotechnology-enabled materials and agents for hemostatic and anti-infective treatments in orthopedic surgery are discussed.

Safety and Efficacy of Topical Chitogel- Deferiprone-Gallium Protoporphyrin in Sheep Model

Objectives: Increasing antimicrobial resistance has presented new challenges to the treatment of recalcitrant chronic rhinosinusitis fuelling a continuous search for novel antibiofilm agents. This study aimed to assess the safety and efficacy of Chitogel (Chitogel®, Wellington New Zealand) combined with novel antibiofilm agents Deferiprone and Gallium Protoporphyrin (CG-DG) as a topical treatment against S. aureus biofilms in vivo.

Methods: To assess safety, 8 sheep were divided into two groups of 7 day treatments (n = 8 sinuses per treatment); (1) Chitogel (CG) with twice daily saline flush, and (2) CG-DG gel with twice daily saline flush. Tissue morphology was analyzed using histology and scanning electron microscopy (SEM). To assess efficacy we used a S. aureus sheep sinusitis model. Fifteen sheep were divided into three groups of 7 day treatments (n = 10 sinuses per treatment); (1) twice daily saline flush (NT), (2) Chitogel (CG) with twice daily saline flush, and (3) CG-DG gel with twice daily saline flush. Biofilm biomass across all groups was compared using LIVE/DEAD BacLight stain and confocal scanning laser microscopy.

Results: Safety study showed no cilia denudation on scanning electron microscopy and no change in sinus mucosa histopathology when comparing CG-DG to CG treated sheep. COMSTAT2 assessment of biofilm biomass showed a significant reduction in CG-DG treated sheep compared to NT controls.

Conclusion: Results indicate that CG-DG is safe and effective against S. aureus biofilms in a sheep sinusitis model and could represent a viable treatment option in the clinical setting.

[Hemostyptics for treatment of junctional vascular injuries : Management of traumatic vascular injuries at the transition from trunk to extremities]

BACKGROUND

Uncontrolled post-traumatic bleeding is still the leading cause of death among trauma patients. In situations of mass casualty incidents (MASCAL) and military conflicts the treatment of uncontrolled critical bleeding is a challenge and associated with a worse outcome due to the austere environment; however, even under optimal treatment circumstances in situations of individual medicine the severity of vascular trauma is underestimated. As a consequence, this leads to a poorer prognosis for patients with (vascular) injuries. From this perspective it was reasonable to intensify the training of physicians, paramedics (Advanced Trauma Life Support^©) and first responders (Hartford consensus) for handling of critical bleeding in traumatized patients. Furthermore, the main emphasis of the revised S3 clinical guidelines on polytrauma/severely injured treatment from 2016 of the German Society for Trauma Surgery is on the preclinical treatment. Despite a renaissance and increasing use of tourniquets, the treatment of bleeding in the transition from the trunk to the extremities (junctional vascular injuries), which are inaccessible to placing a tourniquet, remains a problem.

CONCLUSION

It was the military that in addition to the development of special tourniquets, intensified research programs and the implementation of hemostatic devices and dressings in this anatomical region. This article deals with junctional vascular injuries at the transition between the trunk and the extremities. In addition to the anatomical situation, this article gives the reader an overview of the currently available hemostyptics and their mode of action.