Advances in Hemostatic Wound Dressings: Clinical Implications and Insight

Alginate based hemostatic materials for bleeding management: A review

Severe bleeding has caused significant financial losses as well as a major risk to the lives and health of military and civilian populations. Under some situations, the natural coagulation mechanism of the body is unable to achieve fast hemostasis without the use of hemostatic drugs. Thus, the development of hemostatic materials and techniques is essential. Improving the quality of life and survival rate of patients and minimizing bodily damage requires fast, efficient hemostasis and prevention of bleeding. Alginate is regarded as an outstanding hemostatic polymer because of its non-immunogenicity, biodegradability, good biocompatibility, simple gelation, non-toxicity, and easy availability. This review summarizes the basics of hemostasis and emphasizes the recent developments regarding alginate-based hemostatic systems. Structural modifications and mixing with other materials have widely been used for the improvement of hemostatic characteristics of alginate and for making multifunctional medical devices that not only prevent uncontrolled bleeding but also have antibacterial characteristics, drug delivery abilities, and curing effects. This review is hoped to prepare critical insights into alginate modifications for better hemostatic properties.

Chitosan-based multifunctional hydrogel with bio-adhesion and antioxidant properties for efficient wound hemostasis

Benefiting from the biocompatibility, adhesiveness, and natural extracellular matrix-mimicking ability, hydrogels have received increasing research in recent years. In this study, a hydrogel system composed of dopamine, quaternized ammoniated chitosan (QCS), and polyvinylpyrrolidone was reported to exhibit fast hemostatic properties in Sprague-Dawley rat tail amputation and liver bleeding models. The results showed that this hydrogel had good hemostatic properties. The designed hydrogel showed high swelling ratios in H2O, PBS, and 0.9 % NaCl solution, indicating its capability to absorb tissue residual exudate and form a stable hydrogel. Compared with the control group, the blood loss in Sprague-Dawley rat tail amputation and liver bleeding were reduced by nearly 78 % and 76 %, respectively. Interestingly, dopamine endowed the hydrogel with antioxidant properties, thus holding a great application promise in inflammatory wounds. Furthermore, the designed hydrogel demonstrated good and reversible adhesion properties (12.23 ± 0.22 kPa-24.31 ± 0.55 kPa), ensuring its firm attachment to bleeding wounds of pig skin in wet environments. This research points out a novel path for designing chitosan-based hydrogels for biomedical applications.

The emerging progress on wound dressings and their application in clinic wound management

BACKGROUND

In addition to its barrier function, the skin plays a crucial role in maintaining the stability of the body's internal environment and normal physiological functions. When the skin is damaged, it is important to select proper dressings as temporary barriers to cover the wound, which can exert significant effects on defence against microbial infection, maintaining normal tissue/cell functions, and coordinating the process of wound repair and regeneration. It now forms an important approach in clinic practice to facilitate wound repair.

SEARCH STRATEGIES

We conducted a comprehensive literature search using online databases including PubMed, Web of Science, MEDLINE, ScienceDirect, Wiley Online Library, CNKI, and Wanfang Data. In addition, information was obtained from local and foreign books on biomaterials science and traumatology.

RESULTS

This review focuses on the efficacy and principles of functional dressings for anti-bacteria, anti-infection, anti-inflammation, anti-oxidation, hemostasis, and wound healing facilitation; and analyses the research progress of dressings carrying living cells such as fibroblasts, keratinocytes, skin appendage cells, and stem cells from different origins. We also summarize the recent advances in intelligent wound dressings with respect to real-time monitoring, automatic drug delivery, and precise adjustment according to the actual wound microenvironment. In addition, this review explores and compares the characteristics, advantages and disadvantages, mechanisms of actions, and application scopes of dressings made from different materials.

CONCLUSION

The real-time and dynamic acquisition and analysis of wound conditions are crucial for wound management and prognostic evaluation. Therefore, the development of modern dressings that integrate multiple functions, have high similarity to the skin, and are highly intelligent will be the focus of future research, which could drive efficient wound management and personalized medicine, and ultimately facilitate the translation of health monitoring into clinical practice.

Chitosan-Based Biomaterials for Hemostatic Applications: A Review of Recent Advances

Hemorrhage is a detrimental event present in traumatic injury, surgery, and disorders of bleeding that can become life-threatening if not properly managed. Moreover, uncontrolled bleeding can complicate surgical interventions, altering the outcome of surgical procedures. Therefore, to reduce the risk of complications and decrease the risk of morbidity and mortality associated with hemorrhage, it is necessary to use an effective hemostatic agent that ensures the immediate control of bleeding. In recent years, there have been increasingly rapid advances in developing a novel generation of biomaterials with hemostatic properties. Nowadays, a wide array of topical hemostatic agents is available, including chitosan-based biomaterials that have shown outstanding properties such as antibacterial, antifungal, hemostatic, and analgesic activity in addition to their biocompatibility, biodegradability, and wound-healing effects. This review provides an analysis of chitosan-based hemostatic biomaterials and discusses the progress made in their performance, mechanism of action, efficacy, cost, and safety in recent years.

Structures, Properties, and Bioengineering Applications of Alginates and Hyaluronic Acid

In recent years, polymeric materials have been used in a wide range of applications in a variety of fields. In particular, in the field of bioengineering, the use of natural biomaterials offers a possible new avenue for the development of products with better biocompatibility, biodegradability, and non-toxicity. This paper reviews the structural and physicochemical properties of alginate and hyaluronic acid, as well as the applications of the modified cross-linked derivatives in tissue engineering and drug delivery. This paper summarizes the application of alginate and hyaluronic acid in bone tissue engineering, wound dressings, and drug carriers. We provide some ideas on how to replace or combine alginate-based composites with hyaluronic-acid-based composites in tissue engineering and drug delivery to achieve better eco-economic value.

Potential Hemostatic and Wound Healing Effects of Thermoresponsive Wound Dressing Gel Loaded with Lignosus rhinocerotis and Punica granatum Extracts

Biologically active compounds in Lignosus rhinocerotis and Punica granatum are found to facilitate wound healing and exhibit hemostatic activity, making them a good combination as bioactives for wound dressings. This study, therefore, aimed to evaluate the potential of thermoresponsive gels loaded with L. rhinocerotis (HLRE) and P. granatum (PPE) extracts as dressings for wound treatment. The gels were prepared using Pluronic PF127 polymer and mixed with PEG 400 and/or starch prior to incorporation with both extracts (0.06 to 1 mg/mL). The gelation temperature (Tgel) at the skin temperature was achieved when Pluronic PF127 was mixed with 22% w/v PEG 400 and reduced to 25.7 ± 0.3-26.7 ± 1.2 °C after adding HLRE and PPE. The gels exhibited satisfactory hardness (2.02 ± 0.19-6.45 ± 0.53 N), cohesiveness (0.9 ± 0.07-2.28 ± 0.4 mJ), adhesiveness (5.07 ± 2.41-19.6 ± 1.1 mJ), and viscosity (0.15 ± 0.04-0.95 ± 0.03 Pa.s), suitable for wound dressings. The optimized gels displayed high thrombin activity and cell migration rate (wound closure of 74% ± 12-89% ± 2 within 24 h), demonstrating hemostatic and healing effects. The thermoresponsive gels demonstrated advantages to be used as dressings for treating acute and open wounds.

Preparation of a Bioadhesive Poly(Acrylic Acid)/Polyvinylpyrrolidone Complex Gel and Its Clinical Effect on Dental Hemostasis

Poly(acrylic acid) (PAA) is a water-soluble synthetic polymer that exhibits bioadhesive properties and has been applied in various novel medical devices, such as drug-delivery carriers and hemostatic agents. PAA forms a water-insoluble complex when mixed with polyvinylpyrrolidone (PVP). If PAA and PVP are mixed in water, they form an aggregated precipitate, which neither swells nor adheres to tissues. The formation of the hydrophobic complex was caused by hydrophobic interactions between the main chains of both polymers aligned the same as a zipper. To hinder the zipper-like alignment of the polymer main chains, hyaluronic acid (HA), a macromolecular viscous polysaccharide, was added to the PVP solution prior to complex formation. When the initial concentration of PAA was lower than 0.05%, HA effectively prevented the aggregation of PAA/PVP complexes and resulted in a slightly clouded suspension. Freeze-drying of the mixture yielded a soft white sponge, which could immediately swell in water to form a highly bioadhesive hydrogel. The PAA/PVP complex prepared with HA exhibited high hemostatic efficiency in clinical studies, even in patients on antithrombotic drugs.