Safety of the long-term application of QuikClot Combat Gauze, ChitoGauze PRO and Celox Gauze in a femoral artery injury model in swine - a preliminary study

Rapid synthesis of degradable ester/thioether monomers and their incorporation into thermoset polyurethane foams for traumatic wound healing

Polyurethane (PUr) foam hemostatic dressings are highly effective at controlling bleeding in traumatic wounds, but their traditionally slow degradation rate requires dressing removal, which could result in wound rebleeding. Incorporating degradable linkages into the PUr network can provide a biodegradable dressing that could be left in place during healing, eliminating rebleeding upon removal and providing scaffolding for new tissue ingrowth with no remains of the applied dressing after healing. In this work, a library of degradable PUr foams was synthesized from degradable monomers based on hydrolytically labile esters and oxidatively labile thioethers using rapid click-chemistry reactions. In a twelve-week in vitro degradation study in 3% hydrogen peroxide and 0.1 M sodium hydroxide, incorporation of degradable monomers resulted in significantly increased PUr foam mass loss, offering biodegradable foam dressings that could better match the rate of traumatic wound healing. Changes to foam chemical, mechanical, thermal, and physical properties throughout degradation were also analyzed. Furthermore, the degradable PUr foams had increased platelet interactions, which could improve foam-induced clotting for a more effective hemostatic dressing. Overall, a biodegradable PUr foam hemostatic dressing could significantly improve healing outcomes in traumatic wounds. STATEMENT OF SIGNIFICANCE: A simple, solvent-free, rapid synthesis technique was developed to provide degradable polythiol monomers for use in polyurethane synthesis. The degradable monomers were incorporated into hemostatic polyurethane foams to provide materials with tunable degradation rates within clinically-relevant time frames. The resulting foams and their degradation byproducts were cytocompatible and hemocompatible, and foams made with the new degradable monomers had enhanced blood clotting, enabling their future use as hemostatic dressings.

Damage control packing: How long can it stay?

Damage control (DC) packing is used selectively in patients in shock with extensive abdominal, thoracic, perineal/genital/perirectal, neck/axillae/groin (junctional), and extremity injury to stop bleeding. In multiple casualty scenarios, DC packing may be used to facilitate an abbreviated surgery and thus "buy time". The packing is by guideline or military doctrine removed or exchanged 1-3 days later in a planned reoperation. In remote environments, however, where timely evacuation cannot occur and resources are limited, it may be necessary for packing to be left in place longer than 3 days. Also, in Large Scale Combat Operations, Multi-Domain Operations, and Distributed Maritime Operations, evacuation will be accomplished by nonsurgeons and may last several days. Prolonged retention of packing is associated with complications, but significant rebleeding may occur upon removal. This article reviews the benefits and hazards of DC packing removal to inform decision making by both surgeons and nonsurgeons. We conclude that except for Dismounted Complex Blast Injury most DC gauze packing does not mandatorily need to be removed or exchanged within a three-day window.

External Bleeding and Advanced Biomacromolecules for Hemostasis

Hemorrhage is a significant medical problem that has been an active area of research over the past few decades. The human body has a complex response to bleeding that leads to blood clot formation and hemostasis. Many biomaterials based on various biomacromolecules have been developed to either accelerate or improve the body's natural response to bleeding. This review examines the mechanisms of hemostasis, types of bleeding, and the in vitro or in vivo models and techniques used to study bleeding and hemostatic materials. It provides a detailed overview of the diverse hemostatic materials, including those that are highly absorbent, wet adhesives, and those that accelerate the biochemical cascade of blood clotting. These materials are currently marketed, under preclinical testing, or being researched. In exploring the latest advancements in hemostatic technologies, this paper highlights the potential of these materials to significantly improve bleeding control in clinical and emergency situations.

Potential novel role of the human amniotic membrane as a sustainable hemostat

OBJECTIVES

Acute hemorrhage can cause significant morbidity and mortality arising from trauma, bleeding disorders, surgical procedures, or obstetric complications. Surgical hemostasis methods may fail to stop acute bleeding due to the complex bleeding dynamics of each bleeding type. Therefore, developing safe and effective topical hemostatic agents remains crucial. The human amniotic membrane (hAM) has established clinical evidence of effectiveness in promoting wound healing and tissue regeneration. Despite its unique biological and immunologic properties and its structural composition of established hemostatic elements, the hemostatic role of hAM has not been yet explored. The present study aimed to investigate this potential role and to describe the development protocol and characterization of hAM-derived topical hemostat.

METHODS

Surface electron microscope (SEM) imaging and Fourier transform infrared (FTIR) spectroscopy were used for characterization, and mouse models with induced peritoneal and tail wound bleeding were employed to evaluate the hemostatic effectiveness using physiological studies, in comparison to a chitosan-based combat-scale hemostat.

RESULTS

The hAM hemostat showed a distinctive composition by SEM and FTIR. Applying equal masses of the hAM hemostat, the commercial hemostat, or a combination reduced peritoneal wound bleeding time to averages of 108.4, 86.2, and 76.8 s, respectively, compared to the control group (300 s). Tail wound bleeding times were similarly reduced with no significant difference between the hAM and the commercial hemostat (P values = 0.29, 0.34 in peritoneal and tail wounds, respectively). Neither hemostat affected coagulation time.

CONCLUSION

This study describes a simple cost-effective preparation protocol for a hAM-based hemostatic agent. The long-recognized safety, sustainability, and immunotolerance advantages of hAM can establish superiority over commercial hemostats with reported safety concerns. Robust research validation in larger-scale bleeding models is required for wider applications and severe bleeding types.

The use of a kaolin-based hemostatic dressing to attenuate bleeding in dogs: A series of 4 cases

OBJECTIVE

To describe the use of a synthetic hemostatic dressing, QuikClot Combat Gauze (QCG), in dogs with bleeding wounds.

CASE SERIES SUMMARY

Two dogs presented with bleeding traumatic wounds, and QCG was used to achieve hemostasis during stabilization of these dogs. In the other 2 dogs, QCG was used to help attenuate bleeding associated with a surgical procedure.

NEW OR UNIQUE INFORMATION PROVIDED

While hemostatic dressings have been widely studied and used in human medicine, there is minimal information on the use and efficacy of these hemostatic dressings in veterinary medicine. This case series describes the use of QCG in dogs with hemorrhaging wounds. QCG could be a valuable resource in veterinary emergency and critical care settings.

Evaluation of hemostatic devices in a randomized porcine model of junctional hemorrhage and 72-hour prolonged field care

BACKGROUND

Hemorrhage control in prolonged field care (PFC) presents unique challenges that drive the need for enhanced point of injury treatment capabilities to maintain patient stability beyond the Golden Hour. To address this, two hemostatic agents, Combat Gauze (CG) and XSTAT, were evaluated in a porcine model of uncontrolled junctional hemorrhage for speed of deployment and hemostatic efficacy over 72 hours.

METHODS

The left subclavian artery and subscapular vein were isolated in anesthetized male Yorkshire swine (70-85 kg) and injured via 50% transection, followed by 30 seconds of hemorrhage. Combat Gauze (n = 6) or XSTAT (n = 6) was administered until bleeding stopped and remained within subjects for observation over 72 hours. Physiologic monitoring, hemostatic efficacy, and hematological parameters were measured throughout the protocol. Gross necropsy and histology were performed following humane euthanasia.

RESULTS

Both CG and XSTAT maintained hemostasis throughout the full duration of the protocol. There were no significant differences between groups in hemorrhage volume (CG: 1021.0 ± 183.7 mL vs. XSTAT: 968.2 ± 243.3 mL), total blood loss (CG: 20.8 ± 2.7% vs. XSTAT: 20.1 ± 5.1%), or devices used (CG: 3.8 ± 1.2 vs. XSTAT: 5.3 ± 1.4). XSTAT absorbed significantly more blood than CG (CG: 199.5 ± 50.3 mL vs. XSTAT: 327.6 ± 71.4 mL) and was significantly faster to administer (CG: 3.4 ± 1.6 minutes vs. XSTAT: 1.4 ± 0.5 minutes). There were no significant changes in activated clot time, prothrombin time, or international normalized ratio between groups or compared with baseline throughout the 72-hour protocol. Histopathology revealed no evidence of microthromboemboli or disseminated coagulopathies across evaluated tissues in either group.

CONCLUSION

Combat Gauze and XSTAT demonstrated equivalent hemostatic ability through 72 hours, with no overt evidence of coagulopathies from prolonged indwelling. In addition, XSTAT offered significantly faster administration and the ability to absorb more blood. Taken together, XSTAT offers logistical and efficiency advantages over CG for immediate control of junctional noncompressible hemorrhage, particularly in a tactical environment. In addition, extension of indicated timelines to 72 hours allows translation to PFC.

Injectable zein gel with in situ self-assembly as hemostatic material

Zein is a biocompatible and biodegradable corn protein with promising properties for biomedical applications. It is hydrophobic with the ability to self-assemble in an aqueous medium. It can also form a gel in hydroalcoholic solvents at higher concentrations. Few studies have investigated the biomedical significance of zein gels. Herein, we exploited the injectability and water-responsive increase in stiffness of zein gel to achieve hemostasis by physical blockage of the wound and clot formation. The release of components from the gel further aided blood clotting and gave a higher clot strength than a natural clot, which can prevent rebleeding. Rabbit aortic injury and swine femoral artery injury models were used to evaluate the hemostatic efficacy of the zein gel. Zein gel was effective in both hemostatic models without applying external compression due to an in situ increase in stiffness, while the control (Celox™ Gauze) required external compression at the wound site. The zein gel was easily removed after hemostasis due to hydrophobic self-assembly. Overall, zein gel is proposed as an effective hemostatic product for any wound shape owing to its good shape adaptability and rapid in situ blood-responsive stiffness increase.

A calcium and zinc composite alginate hydrogel for pre-hospital hemostasis and wound care

We developed, characterized, and examined the hemostatic potential of sodium alginate-based Ca²⁺ and Zn²⁺ composite hydrogel (SA-CZ). SA-CZ hydrogel showed substantial in-vitro efficacy, as observed by the significant reduction in coagulation time with better blood coagulation index (BCI) and no evident hemolysis in human blood. SA-CZ significantly reduced bleeding time (≈60 %) and mean blood loss (≈65 %) in the tail bleeding and liver incision in the mice hemorrhage model (p ≤ 0.001). SA-CZ also showed enhanced cellular migration (1.58-fold) in-vitro and improved wound closure (≈70 %) as compared with betadine (≈38 %) and saline (≈34 %) at the 7th-day post-wound creation in-vivo (p < 0.005). Subcutaneous implantation and intra-venous gamma-scintigraphy of hydrogel revealed ample body clearance and non-considerable accumulation in any vital organ, proving its non-thromboembolic nature. Overall, SA-CZ showed good biocompatibility along with efficient hemostasis and wound healing qualities, making it suitable as a safe and effective aid for bleeding wounds.

Shape Memory Polymer Foams With Phenolic Acid-Based Antioxidant and Antimicrobial Properties for Traumatic Wound Healing

The leading cause of trauma-related death before arrival at a hospital is uncontrolled blood loss. Upon arrival at the hospital, microbial infections in traumatic wounds become an additional factor that increases mortality. The development of hemostatic materials with antimicrobial and antioxidant properties could improve morbidity and mortality in these wounds. To that end, phenolic acids (PAs) were successfully incorporated into the network of shape memory polymer (SMP) polyurethane foams by reacting them with isocyanates. Resulting PA-containing SMP foam shape memory properties, antimicrobial and antioxidant activity, and blood and cell interactions were characterized. Results showed that p-coumaric, vanillic, and ferulic acids were successfully incorporated into the SMP foams. The PA-containing SMP foams retained the antimicrobial and antioxidant properties of the incorporated PAs, with ∼20% H₂O₂ scavenging and excellent antimicrobial properties again E. coli (∼5X reduction in CFUs vs. control foams), S. aureus (∼4.5X reduction in CFUs vs. control foams, with comparable CFU counts to clinical control), and S. epidermidis (∼25–120X reduction in CFUs vs. control foams, with comparable CFU counts to clinical control). Additionally, appropriate thermal and shape memory properties of PA foams could enable stable storage in low-profile secondary geometries at temperatures up to ∼55°C and rapid expand within ∼2 min after exposure to water in body temperature blood. PA foams had high cytocompatibility (>80%), non-hemolytic properties, and platelet attachment and activation, with improved cytocompatibility and hemocompatibility in comparison with clinical, silver-based controls. The incorporation of PAs provides a natural non-antibiotic approach to antimicrobial SMP foams with antioxidant properties. This system could improve outcomes in traumatic wounds to potentially reduce bleeding-related deaths and subsequent infections.

Pharmacological comparison of four biopolymeric natural gums as hemostatic agents for management of bleeding wounds: preliminary in vitro and in vivo results

Background

Uncontrolled bleeding is one of the primary reasons for preventable death in both civilian trauma and military battle field. This study evaluates in vitro and in vivo hemostatic potential of four biopolymeric natural gums, namely, gum tragacanth, guar gum, xanthan gum, and gum acacia. In vitro evaluation of whole blood clotting time and erythrocyte agglutination assay were carried out. In vitro cytotoxicity studies with respect to each gum were done in human lymphocytes to ascertain percent cell viability. In vivo hemostatic potential of each gum (as sponge dressing and powder form) was evaluated in Sprague Dawley rats using tail bleeding assay and compared with commercially available hemostatic sponge. Other important parameters like (a) time taken for complete hemostasis, (b) amount of blood absorbed, (c) adherence strength of developed hemostatic dressing(s), (d) incidence of re-bleeding, and (e) survival of animals were also studied.

Results

Of the four test gums studied, xanthan gum (@3mg/ml of blood) and gum tragacanth (@35mg/ml of blood) were able to clot blood in least time (58.75±6.408 s and 59.00±2.082 s, respectively) and exhibited very good hemostatic potential in vitro. Except for xanthan gum, all other test gums did not exhibit any significant cytotoxicity at different time points till 24 h. In rat tail bleeding experiments, gum tragacanth sponge dressing and powder achieved hemostasis in least time (156.2±12.86 s and 76±12.55 s, respectively) and much earlier than commercially available product (333.3±38.84 s; p˂0.01).

Conclusion

Results indicate potential of gum tragacanth to be developed into a suitable hemostatic product.

Mechanism, Functions, and Diagnostic Relevance of FXII Activation by Foreign Surfaces

Factor XII (FXII) is a serine protease zymogen produced by hepatocytes and secreted into plasma. The highly glycosylated coagulation protein consists of six domains and a proline-rich region that regulate activation and function. Activation of FXII results from a conformational change induced by binding ("contact") with negatively charged surfaces. The activated serine protease FXIIa drives both the proinflammatory kallikrein-kinin pathway and the procoagulant intrinsic coagulation cascade, respectively. Deficiency in FXII is associated with a prolonged activated partial thromboplastin time (aPTT) but not with an increased bleeding tendency. However, genetic or pharmacological deficiency impairs both arterial and venous thrombosis in experimental models. This review summarizes current knowledge of FXII structure, mechanisms of FXII contact activation, and the importance of FXII for diagnostic coagulation testing and thrombosis.

Hemostatic materials in wound care

Blood plays an essential role in the human body. Hemorrhage is a critical cause of both military and civilian casualties. The human body has its own hemostatic mechanism that involves complex processes and has limited capacity. However, in emergency situations such as battlefields and hospitals, when the hemostatic mechanism of the human body itself cannot stop bleeding effectively, hemostatic materials are needed for saving lives. In this review, the hemostatic mechanisms and performance of the most commonly used hemostatic materials, (including fibrin, collagen, zeolite, gelatin, alginate, chitosan, cellulose and cyanoacrylate) and the commercial wound dressings based on these materials, will be discussed. These materials may have limitations, such as poor tissue adhesion, risk of infection and exothermic reactions, that may lessen their hemostatic efficacy and cause secondary injuries. High-performance hemostatic materials, therefore, have been designed and developed to improve hemostatic efficiency in clinical use. In this review, hemostatic materials with advanced performances, such as antibacterial capacity, superhydrophobicity/superhydrophilicity, superelasticity, high porosity and/or biomimicry, will be introduced. Future prospects of hemostatic materials will also be discussed in this review.

CaCO3-Chitosan Composites Granules for Instant Hemostasis and Wound Healing

Excessive bleeding induces a high risk of death and is a leading cause of deaths that result from traffic accidents and military conflict. In this paper, we developed a novel porous chitosan-CaCO3 (CS-CaCO3) composite material and investigated its hemostatic properties and wound healing performance. The CS-CaCO3 composites material was prepared via a wet-granulation method. Granulation increases the infiltrating ability of the CS-CaCO3 composites material. The improved water absorption ability was enhanced to 460% for the CS-CaCO3 composites material compared to the CaCO3 or chitosan with only one single component. The coagulation studies in vivo illustrated that the blood clotting time was greatly reduced from 31 s for CaCO3 to 16 s for the CS-CaCO3 composite material. According to the results of the wound healing experiments in rats, it was found that the CS-CaCO3 composite material can promote wound healing. The CS-CaCO3 composite material could accelerate wound healing to a rate of 9 days, compared with 12 days for the CaCO3. The hemostatic activity, biocompatibility, and low cost of CS-CaCO3 composite material make it a potential agent for effective hemostatic and wound healing materials.

Hemostatic agents for prehospital hemorrhage control: a narrative review

Hemorrhage is the leading cause of preventable death in combat trauma and the secondary cause of death in civilian trauma. A significant number of deaths due to hemorrhage occur before and in the first hour after hospital arrival. A literature search was performed through PubMed, Scopus, and Institute of Scientific Information databases for English language articles using terms relating to hemostatic agents, prehospital, battlefield or combat dressings, and prehospital hemostatic resuscitation, followed by cross-reference searching. Abstracts were screened to determine relevance and whether appropriate further review of the original articles was warranted. Based on these findings, this paper provides a review of a variety of hemostatic agents ranging from clinically approved products for human use to newly developed concepts with great potential for use in prehospital settings. These hemostatic agents can be administered either systemically or locally to stop bleeding through different mechanisms of action. Comparisons of current hemostatic products and further directions for prehospital hemorrhage control are also discussed.