Hemostatic Powder vs Standard Endoscopic Treatment for Gastrointestinal Tumor Bleeding: A Multicenter Randomized Trial.

BACKGROUND & AIMS: Current guidelines vary as to their recommendations addressing the role of hemostatic powders when managing patients with malignant gastrointestinal (GI) bleeding because these are based on very-low- to low-quality evidence, in large part due to a paucity of randomized trial data. METHODS: This was a patient- and outcome assessor-blinded, multicenter, randomized controlled trial. Patients presenting with active bleeding from an upper or lower GI lesion suspected to be malignant at index endoscopy between June 2019 and January 2022 were randomly allocated to receive either TC-325 alone or standard endoscopic treatment (SET). The primary outcome was 30-day rebleeding, and secondary objectives included immediate hemostasis and other clinically relevant endpoints. RESULTS: Overall, 106 patients made up the study population (55 TC-325 and 51 SET, after 1 exclusion in the TC-325 group and 5 in the SET group). Baseline characteristics and endoscopic findings did not differ between the groups. Thirty-day rebleeding was significantly lower in the TC-325 (2.1% TC-325 vs 21.3% SET; odds ratio, 0.09; 95% confidence interval [CI], 0.01-0.80; P = .003). Immediate hemostasis rates were 100% in the TC-325 group vs 68.6% in the SET group (odds ratio, 1.45; 95% CI, 0.93-2.29; P < .001). Other secondary outcomes did not differ between the 2 groups. Independent predictors of 6-month survival included the Charlson comorbidity index (hazard ratio, 1.17; 95% CI, 1.05-1.32; P = .007) and receiving an additional nonendoscopic hemostatic or oncologic treatment during 30 days after the index endoscopy (hazard ratio, 0.16; 95% CI, 0.06-0.43; P < .001) after adjustment for functional status, Glasgow-Blatchford score, and an upper GI source of bleeding. CONCLUSION: The TC-325 hemostatic powder results in greater immediate hemostasis rates followed by lower 30-day rebleeding rates when compared to contemporary SET. (ClinicalTrials.gov, Number: NCT03855904).

Perioperative bleeding control in total hip arthroplasty: hemostatic powder vs. tranexamic acid-a prospective randomized controlled trial.

BACKGROUND: Perioperative bleeding in total hip arthroplasty (THA) can lead to various problems, so effective management of blood loss is needed. This prospective, single-blind, randomized controlled trial aimed to compare the efficacy of topical administration of SURGICEL® (a hemostatic agent of oxidized regenerated cellulose) powder (SP) and tranexamic acid (TXA) in controlling perioperative bleeding during THA. MATERIALS AND METHODS: In total, 114 patients undergoing THA for osteoarthritis were randomized to either group S (THA with SP) or group T (THA with TXA). Data including patient demographics, laboratory data (C-reactive protein [CRP], hemoglobin, and hematocrit), operative time, and intraoperative blood loss were analyzed. Clinical outcomes were assessed using WOMAC, JOA, FJS scores, and visual analog scale (VAS) scores. Primary outcomes were estimated total and postoperative blood loss, while secondary outcomes included hematological test results and various clinical scores. RESULTS: 57 patients were allocated to each group, with 55 in group S and 56 in group T were finally included in the analysis. There was no significant difference (p = 0.141) in estimated total blood loss between group S (788.2 ± 350.1 ml) and group T (714.1 ± 318.4 ml). Hemoglobin and hematocrit levels and WOMAC, and FJS scores were not significantly different between the two groups at any time point. CRP levels were significantly different on postoperative days 4 and 7, and JOA score was significantly different on preoperative and postoperative period. However, the differences in CRP and JOA score values themselves were relatively small and not clinically different. CONCLUSIONS: Topical administration of SP is as effective as TXA in reducing perioperative bleeding in patients undergoing THA. Additionally, no significant difference was observed in early postoperative clinical outcomes between SP and TXA. LEVEL OF EVIDENCE: Therapeutic Level I. TRIAL REGISTRATION: The University Hospital Medical Information Network (UMIN) registration number UMIN000047607.

Comparison of a Polysaccharide Hemostatic Powder and Conventional Therapy for Peptic Ulcer Bleeding.

BACKGROUND & AIMS: Hemostatic powders have been clinically used in the treatment of gastrointestinal bleeding. We investigated the non-inferiority of a polysaccharide hemostatic powder (PHP), compared with conventional endoscopic treatments, for peptic ulcer bleeding (PUB). METHODS: This study was a prospective multi-center, randomized, open-label, controlled trial at 4 referral institutions. We consecutively enrolled patients who had undergone emergency endoscopy for PUB. The patients were randomly assigned to either a PHP or conventional treatment group. In the PHP group, diluted epinephrine was injected, and the powder was applied as a spray. Conventional endoscopic treatment included the use of electrical coagulation or hemoclipping after injection of diluted epinephrine. RESULTS: Between July 2017 and May 2021, 216 patients were enrolled in this study (PHP group, 105; control group, 111). Initial hemostasis was achieved in 92 of 105 patients (87.6%) in the PHP group and 96 of 111 patients (86.5%) in the conventional treatment group. Re-bleeding did not differ between the 2 groups. In subgroup analysis, the initial hemostasis failure rate in the conventional treatment group was 13.6% for Forrest IIa cases; however, there was no initial hemostasis failure in the PHP group (P = .023). Large ulcer size (≥15 mm) and chronic kidney disease with dialysis were independent risk factors for re-bleeding at 30 days. No adverse events were associated with PHP use. CONCLUSIONS: PHP is not inferior to conventional treatments and could be useful in initial endoscopic treatment for PUB. Further studies are needed to confirm the re-bleeding rate of PHP. CLINICALTRIALS: gov, Number: NCT02717416).

Hemostasis Techniques for Non-variceal Upper GI Hemorrhage: Beyond Injection and Cautery.

B. Nulsen D. M. Jensen.

AGA Clinical Practice Update on Endoscopic Therapies for Non-Variceal Upper Gastrointestinal Bleeding: Expert Review.

DESCRIPTION: The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update is to review the available evidence and best practice advice statements regarding the use of endoscopic therapies in treating patients with non-variceal upper gastrointestinal bleeding. METHODS: This expert review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Gastroenterology. This review is framed around the 10 best practice advice points agreed upon by the authors, which reflect landmark and recent published articles in this field. This expert review also reflects the experiences of the authors who are gastroenterologists with extensive experience in managing and teaching others to treat patients with non-variceal upper gastrointestinal bleeding (NVUGIB). BEST PRACTICE ADVICE 1: Endoscopic therapy should achieve hemostasis in the majority of patients with NVUGIB. BEST PRACTICE ADVICE 2: Initial management of the patient with NVUGIB should focus on resuscitation, triage, and preparation for upper endoscopy. After stabilization, patients with NVUGIB should undergo endoscopy with endoscopic treatment of sites with active bleeding or high-risk stigmata for rebleeding. BEST PRACTICE ADVICE 3: Endoscopists should be familiar with the indications, efficacy, and limitations of currently available tools and techniques for endoscopic hemostasis, and be comfortable applying conventional thermal therapy and placing hemoclips. BEST PRACTICE ADVICE 4: Monopolar hemostatic forceps with low-voltage coagulation can be an effective alternative to other mechanical and thermal treatments for NVUGIB, particularly for ulcers in difficult locations or those with a rigid and fibrotic base. BEST PRACTICE ADVICE 5: Hemostasis using an over-the-scope clip should be considered in select patients with NVUGIB, in whom conventional electrosurgical coagulation and hemostatic clips are unsuccessful or predicted to be ineffective. BEST PRACTICE ADVICE 6: Hemostatic powders are a noncontact endoscopic option that may be considered in cases of massive bleeding with poor visualization, for salvage therapy, and for diffuse bleeding from malignancy. BEST PRACTICE ADVICE 7: Hemostatic powder should be preferentially used as a rescue therapy and not for primary hemostasis, except in cases of malignant bleeding or massive bleeding with inability to perform thermal therapy or hemoclip placement. BEST PRACTICE ADVICE 8: Endoscopists should understand the risk of bleeding from therapeutic endoscopic interventions (eg, endoluminal resection and endoscopic sphincterotomy) and be familiar with the endoscopic tools and techniques to treat intraprocedural bleeding and minimize the risk of delayed bleeding. BEST PRACTICE ADVICE 9: In patients with endoscopically refractory NVUGIB, the etiology of bleeding (peptic ulcer disease, unknown source, post surgical); patient factors (hemodynamic instability, coagulopathy, multi-organ failure, surgical history); risk of rebleeding; and potential adverse events should be taken into consideration when deciding on a case-by-case basis between transcatheter arterial embolization and surgery. BEST PRACTICE ADVICE 10: Prophylactic transcatheter arterial embolization of high-risk ulcers after successful endoscopic therapy is not encouraged.

Efficacy of a novel hemostatic adhesive powder in patients with upper gastrointestinal tumor bleeding.

BACKGROUND: Gastrointestinal tumor bleeding remains a clinical challenge because it is difficult to treat with conventional endoscopic hemostatic options. Recently, an endoscopic hemostatic powder (UI-EWD) was developed and reported to provide effective control of upper gastrointestinal bleeding. The aim of current study was to evaluate the feasibility and efficacy of this novel hemostatic powder in tumor bleeding. METHODS: A total of 41 consecutive patients with upper gastrointestinal tumor bleeding were included. UI-EWD was applied in all patients as an auxiliary hemostatic method as a salvage therapy or monotherapy during endoscopic treatment. Hemostasis success rates, adverse event related to UI-EWD, and rates of re-bleeding were evaluated. RESULTS: In all cases, UI-EWD application was successful at tumor bleeding sites. Immediate hemostasis occurred in 40/41 (97.5%) patients, and re-bleeding within 28 days occurred in 10 of 40 (22.5%) patients that achieved initial hemostasis. The success rate of immediate hemostasis for UI-EWD monotherapy was 100% (23/23). The re-bleeding rate at 28 days after UI-EWD monotherapy was 26.1% (6/23). No adverse events associated with UI-EWD application were encountered. CONCLUSIONS: The success rate of UI-EWD for immediate hemostasis in cases of GI tumor bleeding was excellent and UI-EWD produced promising results with respect to the prevention of re-bleeding. Based on these results, we suggest that UI-EWD be considered an effective salvage therapy or even monotherapy for GI tumor bleeding.

New Developments in Managing Variceal Bleeding.

Liver cirrhosis is the end stage of chronic liver disease, independent of etiology, and is characterized by accumulation of fibrotic tissue and conversion of the normal liver parenchyma into abnormal regenerative nodules. Complications include portal hypertension (PH) with gastroesophageal varices, ascites, hepatorenal syndrome, hepatic encephalopathy, bacteremia, and hypersplenism. The most life-threatening complication of liver cirrhosis is acute variceal bleeding (AVB) which is associated with increased mortality that, despite recent progress in management, is still around 20% at 6 weeks. Combined treatment with vasoactive drugs, prophylactic antibiotics, and endoscopic techniques is the recommended standard of care for patients with acute variceal bleeding. There are many promising new modalities including the combination of coil and glue injection for management of bleeding or non-bleeding gastric varices and hemostatic powder application, that requires minimal expertise, when performed early after admission of a cirrhotic patient with AVB and overt hematemesis acting as a bridge therapy till definitive endoscopic therapy can be performed in hemodynamically stable conditions and without acute bleeding.

Treatment of gastrointestinal bleeding with hemostatic powder (TC-325): a multicenter study.

INTRODUCTION: Hemostatic powder (TC-325) is a new tool for treatment of gastrointestinal bleeding that allows the treatment of large surfaces with active bleeding. The aim was to describe the initial success of TC-325 for the control of GI bleeding. MATERIALS AND METHODS: We did a multicenter cohort study with patients admitted to the endoscopy service for GI bleeding. A format was generated to standardize the information obtained in each center. It was determined whether this treatment had been used as a single therapy or as a combination therapy. Descriptive statistics with medians and ranges, or averages with SD according to distribution. RESULTS: Eighty-one patients with 104 endoscopic procedures were included. The median number of endoscopic procedures was 1 (1-3). In the first procedure, the initial success rate was 98.8% (n = 80), failure rate was 1.2% (n = 1), and rebleeding rate was 20% (n = 16). The majority of rebleeding cases occurred within the first 3 days (12/16, 75%). There was no association between rebleeding and etiology (malignant or benign; P = 0.6). In first procedure, 44 (54%) cases had monotherapy with TC-325 and 37 (46%) cases had a combined endoscopic therapy. There were no differences in initial success or rebleeding rates when TC-325 was used as monotherapy versus combined therapy (P = 0.7). The mortality rate was 4% (3/81). CONCLUSION: TC-325 is effective for achieving initial control of bleeding in patients with different GI etiologies. The rate of bleeding recurrence is considerable in both patients with benign and malignant etiology.

Application techniques of a novel hemostat in cardiac operations: HEMOBLAST.

BACKGROUND: Postoperative bleeding complications are associated with less favorable outcomes in cardiac surgery and contribute to excessive overall healthcare costs. HEMOBLAST (Biom'up, Lyon, France) (HB) is a novel ready-to-use hemostatic powder that consists of porcine collagen, bovine chondroitin sulfate, and human pooled plasma thrombin that may help reduce surgical bleeding. AIMS: The aim of this study was to describe the techniques of application for this new combination powder-based hemostat, HB, and demonstrate its use employing photographs of application methods during cardiac procedures. MATERIALS AND METHODS: The initial 24 procedures in which HB was used at our institution included: left ventricular assist device (LVAD) insertions, lung transplants, heart transplants, aortic valve replacements, coronary artery bypass grafting, and mitral valve repair. RESULTS: Hemostasis was achieved in all cases and there were no instances of mediastinitis, sternal infections, allergic reactions, or 30-day mortality. DISCUSSION: This report describes the best methods of application of HB including use for treatment of mediastinal bleeding in a re-operative procedure in a patient on antiplatelet agents and sternal bleeding during an LVAD insertion. Proper application can facilitate excellent hemostasis using this powder. CONCLUSION: HB is a novel powder-based multiple component hemostatic agent that promotes focal or large area hemostasis. We have presented the techniques of use that are important to the successful application of HB to facilitate hemostasis.

Evaluation of the safety and efficacy of a new hemostatic powder using a quantitative surface bleeding severity scale.

AIMS OF THE STUDY: The safety and efficacy of a hemostatic powder (HP) versus a control agent, absorbable gelatin sponge and thrombin (G + T), were assessed, using a validated, quantitative bleeding severity scale. METHODS: Subjects were randomized to receive HP (256 subjects) or G + T (132 subjects) for treatment of minimal, mild, or moderate bleeding at 20 investigational sites. The primary efficacy endpoint was non-inferiority of HP relative to G + T for success at achieving hemostasis within 6 minutes. Secondary endpoints in rank order included: superiority of HP relative to G + T in mean preparation time; non-inferiority of HP relative to G + T for achieving hemostasis within 3 min; superiority of HP relative to G + T for achieving hemostasis within 6 min; and superiority of HP relative to G + T for success for achieving hemostasis within 3 min. RESULTS: A total of 388 subjects were included in the primary efficacy analysis. At 6 min, hemostasis was achieved in 93.0% (238/256) of the HP group compared to 77.3% (102/132) of the G + T group (non-inferiority P < 0.0001, superiority P < 0.0001). All secondary endpoints were met. Complications were comparable between treatment groups. CONCLUSIONS: HP had superior rates of hemostasis, shorter preparation time, and a similar safety profile compared to G + T in this prospective, randomized trial using quantitative bleeding severity criteria.

Effectiveness of the polysaccharide hemostatic powder in non-variceal upper gastrointestinal bleeding: Using propensity score matching.

BACKGROUND AND AIM: Recently, the application of hemostatic powder to the bleeding site has been used to treat active upper gastrointestinal bleeding (UGIB). We aimed to assess the effectiveness of the polysaccharide hemostatic powder (PHP) in patients with non-variceal UGIB. METHODS: We reviewed prospectively collected 40 patients with UGIB treated with PHP therapy between April 2016 and January 2017 (PHP group) and 303 patients with UGIB treated with conventional therapy between April 2012 and October 2014 (conventional therapy group). We compared the rate of successful hemostasis and the rebleeding between the two groups after as well as before propensity score matching using the Glasgow-Blatchford score and Forrest classification. RESULTS: Thirty patients treated with the PHP and 60 patients treated with conventional therapy were included in the matched groups. Baseline patient characteristics including comorbidities, vital signs, and bleeding scores were similar in the matched groups. The rate of immediate hemostasis and 7-day and 30-day rebleeding were also similar in the two groups before and after matching. In the subgroup analysis, no significant differences in immediate hemostasis or rebleeding rate were noted between PHP in monotherapy and PHP combined with a conventional hemostatic method. At 30 days after the therapy, there were no significant PHP-related complications or mortality. CONCLUSIONS: Given its safety, the PHP proved feasible for endoscopic treatment of UGIB, having similar effectiveness as that of conventional therapy. The PHP may become a promising hemostatic method for non-variceal UGIB.

Efficacy of hemostatic powder in preventing bleeding after gastric endoscopic submucosal dissection in high-risk patients.

BACKGROUND AND AIM: The prevention of post-endoscopic submucosal dissection (ESD) bleeding in high-risk patients is an important problem. This study evaluated the efficacy of polysaccharide hemostatic powder in preventing post-ESD bleeding in high-risk patients. METHODS: Patients at high risk for post-ESD bleeding were prospectively enrolled between December 2015 and July 2016. A high risk of post-ESD bleeding was considered if the patients were taking antithrombotic agents or had undergone a large resection (specimen size ≥ 40 mm). The endpoints were Forrest classification of the post-ESD ulcer on second-look endoscopy 2 days after the procedure and bleeding rates within 48 h and at 4 weeks. RESULTS: Forty-four patients underwent gastric ESD and treatment with hemostatic powder. Among them, 33 patients (70.5%) underwent large resection (≥ 40 mm) without antithrombotic therapy, and 13 patients (29.5%) received antithrombotic therapy. The mean resected specimen size was 55.3 ± 13.9 mm. The proportion of high-risk delayed bleeding lesions (Forrest IIa) at second-look endoscopy was 4.5% (2/44). The overall bleeding rate was 9.1% (4/44). There was no early bleeding event. The median (interquartile range) timing of bleeding after the procedure was 12.5 (interquartile range 10.3-15.5) days. The bleeding rate in the large resection (≥ 40 mm) group without antithrombotic therapy and the antithrombotic therapy group was 3.2% (1/33) and 23.1% (3/13), respectively. CONCLUSIONS: Hemostatic powder may be a promising new simple and effective method to prevent early post-ESD bleeding in high-risk patients, especially for those with larger resection. (Clinical trial registration number: NCT02625792).

Coagulating blood into adhesive gel by hybrid powder based on oppositely charged polysaccharide/tannic acid-modified mesoporous bioactive glass.

Hemostatic powder is widely utilized in emergency situations to control bleeding due to its ability to work well on wounds with irregular shapes, ease of application, and long-term stability. However, traditional powder often suffers from limited tissue adhesion and insufficient support for blood clot formation, leaving it susceptible to displacement by the flow of blood. This study introduces a hemostatic powder composed of tannic modified mesoporous bioactive glass (TMBG), cationic quaternized chitosan (QCS), and anionic hyaluronic acid modified with catechol group (HADA). The resulting TMBG/QCS/HADA based hemostatic powder (TMQH) rapidly absorbs plasma, concentrating blood coagulation factors. Simultaneously, the water-soluble QCS and HADA interact to form a 3D network structure, which can be strengthened by crosslinking with TMBG. This network effectively captures clustered blood coagulation factors, leading to a strong and adhesive thrombus that resists disruption from blood flow. TMQH exhibits superior efficacy in promoting hemostasis compared to Celox™ both in rat arterial injuries and non-compressible liver puncture wounds. TMQH demonstrates excellent antibacterial activity, cytocompatibility, and blood compatibility. These outstanding superiorities in blood clotting capability, wet tissue adhesion, antibacterial activity, safety for living organisms, ease of application, and long-term stability, make TMQH highly suitable for emergency hemostasis.

Current status and clinical outcome of endoscopic hemostatic powder in gastrointestinal bleeding: a retrospective multicenter study.

Background/Aims: Few multicenter studies have investigated the efficacy of hemostatic powders in gastrointestinal (GI) bleeding. We aimed to investigate the clinical outcomes of hemostatic powder therapy and the independent factors affecting rebleeding rates. Methods: We retrospectively recruited patients who underwent a new hemostatic adhesive powder (UI-EWD; Next-Biomedical) treatment for upper and lower GI bleeding between January 1, 2020 and March 1, 2023. We collected patients' medical records and bleeding lesions. The primary outcomes were clinical and technical success rates, and the secondary outcomes were early, delayed, and refractory bleeding, mortality, and factors affecting early rebleeding rates. Results: This study enrolled 135 patients (age: 67.7±13.6 years, male: 74.1%) from five hospitals. Indications for UI-EWD were peptic ulcers (51.1%), post-procedure-related bleeding (23.0%), and tumor bleeding (19.3%). The clinical and technical success rates were both 97%. The early, delayed, and refractory rebleeding rates were 19.3%, 11.1%, and 12.8%, respectively. Initially elevated blood urea nitrogen (BUN) levels (p=0.014) and Forrest classification IA or IB compared with IIA or IIB (p=0.036) were factors affecting early rebleeding. Conclusions: UI-EWD showed high clinical and technical success rates; however, rebleeding after UI-EWD therapy in patients with initially high BUN levels and active bleeding, according to the Forrest classification, should be considered.

Hydro-Sensitive, In Situ Ultrafast Physical Self-Gelatinizing, and Red Blood Cells Strengthened Hemostatic Adhesive Powder with Antibiosis and Immunoregulation for Wound Repair.

Immediate and effective hemostatic treatments for complex bleeding wounds are an urgent clinical demand. Hemostatic materials with characteristics of adhesion, sealing, anti-infection, and concrescence promotion have drawn growing concerns. However, pure natural multifunctional hemostatic materials with in situ ultrafast self-gelation are rarely reported. In this study, a hydro-sensitive collagen/tannic acid (ColTA) natural hemostatic powder is developed that can in situ self-gel to form adhesive by the non-covalent crosslinking between tannic acid (TA) and collagen (Col) in liquids. The physical interactions endow ColTA adhesive with the characteristics of instantaneous formation and high adhesion at various substrate surfaces. Crucially, ColTA powder adhesive shows an enhanced adhesion performance in the presence of blood due to the electrostatic interactions between ColTA adhesive and red blood cells, conducive to effective in situ sealing and rapid hemostasis. The biocompatible and hemocompatible ColTA adhesive can effectively control bleeding and seal the wounds of the caudal vein, liver, heart, and femoral arteries in rats. Furthermore, the low-cost and ready-to-use ColTA adhesive powder also possesses good antibacterial and inhibiting biofilm formation ability, and can efficiently regulate immune response by the NF-κB pathway to promote wound repair, making it a highly promising hemostatic material with great potential for biomedical applications.

Gluing blood into adhesive gel by oppositely charged polysaccharide dry powder inspired by fibrin fibers coagulation mediator.

Hemostatic powders that adapt to irregularly shaped wounds, allowing for easy application and stable storage, have gained popularity for first-aid hemorrhage control. However, traditional powders often provide weak thrombus support and exhibit limited tissue adhesion, making them susceptible to dislodgment by the bloodstream. Inspired by fibrin fibers coagulation mediator, we have developed a bi-component hemostatic powder composed of positively charged quaternized chitosan (QCS) and negatively charged catechol-modified alginate (Cat-SA). Upon application to the wound, the bi-component powders (QCS/Cat-SA) rapidly absorb plasma and dissolve into chains. These chains interact with each other to form a network, which can effectively bind and entraps clustered red blood cells and platelets, ultimately leading to the creation of a durable and robust thrombus. Significantly, these interconnected polymers adhere to the injury site, offering protection against thrombus disruption caused by the bloodstream. Benefiting from these synthetic properties, QCS/Cat-SA demonstrates superior hemostatic performance compared to commercial hemostatic powders like Celox™ in both arterial injuries and non-compressible liver puncture wounds. Importantly, QCS/Cat-SA exhibits excellent antibacterial activity, cytocompatibility, and hemocompatibility. These advantages of QCS/Cat-SA, including strong blood clotting, wet tissue adherence, antibacterial activity, biosafety, ease of use, and stable storage, make it a promising hemostatic agent for emergency situations.

A Self-Assembly Pro-Coagulant Powder Capable of Rapid Gelling Transformation and Wet Adhesion for the Efficient Control of Non-Compressible Hemorrhage.

Rapid and effective control of non-compressible massive hemorrhage poses a great challenge in first-aid and clinical settings. Herein, a biopolymer-based powder is developed for the control of non-compressible hemorrhage. The powder is designed to facilitate rapid hemostasis by its excellent hydrophilicity, great specific surface area, and adaptability to the shape of wound, enabling it to rapidly absorb fluid from the wound. Specifically, the powder can undergo sequential cross-linking based on "click" chemistry and Schiff base reaction upon contact with the blood, leading to rapid self-gelling. It also exhibits robust tissue adhesion through covalent/non-covalent interactions with the tissues (adhesive strength: 89.57 ± 6.62 KPa, which is 3.75 times that of fibrin glue). Collectively, this material leverages the fortes of powder and hydrogel. Experiments with animal models for severe bleeding have shown that it can reduce the blood loss by 48.9%. Studies on the hemostatic mechanism also revealed that, apart from its physical sealing effect, the powder can enhance blood cell adhesion, capture fibrinogen, and synergistically induce the formation of fibrin networks. Taken together, this hemostatic powder has the advantages for convenient preparation, sprayable use, and reliable hemostatic effect, conferring it with a great potential for the control of non-compressible hemorrhage.

Cohering Plasma into Adhesive Gel by Natural Biopolymer-Nanoparticle Hybrid Powder for Efficient Hemostasis and Wound Healing.

Hemostatic powder is commonly used in emergency bleeding control due to its suitability for irregularly shaped wounds, ease of use, and stable storage. However, traditional powder often has limited tissue adhesion and weak thrombus support, which makes it vulnerable to displacement by blood flow. Herein, we have developed a tricomponent hemostatic powder (MQS) composed of mesoporous bioactive glass nanoparticle (MBG), positively charged quaternized chitosan (QCS), and negatively charged catechol-modified alginate (SADA). Upon application to the wound, MBG with its high specific surface area quickly absorbs plasma, concentrating the blood coagulation factor. Simultaneously, the water-soluble QCS and SADA interact with each other and form a net, which can be further cross-linked by MBG. This network efficiently binds and entraps clustered blood coagulation factors, ultimately resulting in the formation of a durable and robust thrombus. Furthermore, the formed net adheres to the injury site, offering protection against thrombus disruption caused by the bloodstream. Benefiting from the synergistic effect of these three components, MQS demonstrates superior hemostatic performance compared to commercial hemostatic powders like Celox in both arterial injuries and noncompressible liver puncture wounds. Furthermore, MQS can effectively accelerate wound healing. In addition, MQS exhibits excellent antibacterial activity, cytocompatibility, and hemocompatibility. These advantages of MQS, including strong blood clotting, wet tissue adherence, antibacterial activity, wound healing ability, biosafety, ease of use, and stable storage, make it a promising hemostatic agent for emergency situations.

Hydrogel-Transformable Antioxidant Poly-γ-Glutamic Acid/Polyethyleneimine Hemostatic Powder for Efficient Wound Hemostasis.

Hemostatic powder, which can absorb large amounts of water and tends to produce repeated hydration with tissue, has been clinically proven as an ideal engineering material for treating wounds and tissues. We herein designed a polypeptide-based hemostatic powder. A water-soluble polypeptide, γ-polyglutamic acid (γ-PGA), was mixed with the polyethyleneimine (PEI), N-hydroxysuccinimide, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide. The solution of these polymers was lyophilized to harvest the γ-PGA/PEI powder (PP hemostatic powder). When deposited on a bleeding wound, the PP hemostatic powder can quickly absorb a large amount of blood and interstitial fluid, concentrate coagulation factors, coagulate blood cells, and eventually form a stable mechanical hydrogel. The wound bleeding time of the PP hemostatic powder group was 1.8 ± 0.4 min, significantly lower than that of the commercial chitosan hemostatic powder group (2.8 ± 0.4 min). The PP hemostatic powder was endowed with antioxidant capacity by introducing protocatechuic aldehyde, which can effectively inhibit inflammation and promote wound healing. Therefore, via preparation through a facile lyophilization method, the PP hemostatic powder is expected to find a wide application prospect as a qualified hemostatic powder.