Polysaccharide hemostatic powder to prevent bleeding after endoscopic submucosal dissection in high risk patients: a randomized controlled trial

A self-hygroscopic, rapidly self-gelling polysaccharide-based sponge with robust wet adhesion for non-compressible hemorrhage control and infected wounds healing

Uncontrollable non-compressible hemorrhage and traumatic infection have been major causes of mortality and disability in both civilian and military populations. A dressing designed for point-of-care control of non-compressible hemorrhage and prevention of traumatic infections represents an urgent medical need. Here, a novel self-gelling sponge OHN@ε-pL is developed, integrating N-succinimidyl ester oxidized hyaluronic acid (OHN) and ε-poly-L-lysine (ε-pL). Upon application to the wound site, the sponge can rapidly absorb interfacial fluids and undergo a phase transition from sponge to gel. The transformed gel facilitates robust tissue adhesion and achieves synergistic hemostasis by enriching coagulation factors within the sponge phase and providing a barrier effect in the gel phase. The in vitro and in vivo studies revealed that the optimized OHN@ε-pL3 sponge possesses self-gelling capability, tissue adhesion, enhanced coagulation ability, and exhibits excellent biocompatibility and antibacterial efficacy. In hemostasis, OHN@ε-pL3 sponges exhibited reduced blood loss and decreased hemostatic time compared to commercial hemostatic agents, as demonstrated in rat liver, femoral vein, and tail truncation bleeding models. Furthermore, the OHN@ε-pL3 sponge exhibited superior performance in accelerating wound closure and healing of S. aureus-infected wounds. Collectively, OHN@ε-pL sponges represent a promising candidate for medical dressings, specifically for managing uncontrollable non-compressible hemorrhage and traumatic infections.

Evaluating the efficacy of a novel hemostatic powder compared with traditional treatments in nonvariceal upper GI bleeding: a multicenter, randomized, noninferiority study

BACKGROUND AND AIMS

Hemostatic powders have been rapidly developed and used to treat GI bleeding. We aimed to investigate the noninferiority of the newly developed hemostatic powder (CEGP-003; CGBio, Seongnam, South Korea) compared with conventional endoscopic treatments for nonvariceal upper GI bleeding (NVUGIB).

METHODS

This prospective, multicenter, randomized, open-label, controlled trial was conducted at 4 referral institutions. We enrolled consecutive patients who underwent emergency endoscopy for NVUGIB. The patients were randomly assigned to either the CEGP-003 group or the conventional treatment group. In the CEGP-003 group, the hemostatic powder was applied as a spray. Conventional endoscopic treatments included electrical coagulation and use of hemostatic clips.

RESULTS

Between November 2019 and June 2022, 218 patients were enrolled (CEGP-003 group, 108; conventional group, 110). Initial hemostasis was achieved in 104 of 108 patients (96.3%) in the CEGP-003 group and 101 of 110 patients (91.8%) in the conventional treatment group. The CEGP-003 group exhibited a significantly higher recurrent bleeding rate than the conventional treatment group. Multivariate analysis showed that age, duodenum and middle one-third of the stomach, and CEGP-003 use as the initial hemostatic treatment were independent risk factors for recurrent bleeding. No adverse events were associated with CEGP-003.

CONCLUSIONS

CEGP-003 demonstrates promise as an initial endoscopic therapy for NVUGIB. However, close monitoring is warranted because of the risk of recurrent bleeding. (Clinical trial registration number: KCT0004655.).

Efficacy of hemostatic powder monotherapy versus conventional endoscopic treatment for nonvariceal GI bleeding: a meta-analysis and trial sequential analysis

BACKGROUND AND AIMS

Hemostatic powder (HP) is a novel hemostasis modality for nonvariceal GI bleeding. This meta-analysis was performed to evaluate the efficacy of HP monotherapy versus conventional endoscopic treatment (CET) for nonvariceal GI bleeding.

METHODS

PubMed, EMBASE, and Cochrane Library databases were systematically searched from inception to October 16, 2023. The primary outcomes were the initial hemostatic rate and the 30-day recurrent bleeding rate. After the meta-analysis, a trial sequential analysis (TSA) was also conducted to decrease the risk of random errors and validate the result.

RESULTS

The meta-analysis included 8 studies, incorporating 653 patients in total. Given significant heterogeneity, all analyses were segregated into malignancy-related and nonmalignancy-related GI bleeding lesions. For the former, HP monotherapy significantly improved the initial hemostasis rate and 30-day recurrent bleeding rate compared with CET (relative risk [RR], 1.50; 95% confidence interval [CI], 1.28-1.75; P < .001; RR, .32; 95% CI, .12-.86; P = .02, respectively), and TSA supported the results. For nonmalignancy-related GI bleeding, HP monotherapy and CET have similar initial hemostasis and 30-day recurrent bleeding rates (RR, 1.08; 95% CI, .98-1.19; P = .11; RR, 1.15; 95% CI, .46-2.90; P = .76, respectively), but the TSA failed to confirm the results.

CONCLUSIONS

HP monotherapy surpassed CET in terms of the initial hemostasis rate and 30-day recurrent bleeding rate for patients with malignancy-related GI bleeding. However, their relative efficacy for nonmalignancy-related GI bleeding remains unresolved.

Tumor Microenvironment Targeted by Polysaccharides in Cancer Prevention: Expanding Roles of Gut Microbiota and Metabolites

Since the development of immune checkpoint inhibitors (ICIs), immunotherapy has been widely used as a novel cancer treatment. However, the efficacy of tumor immunotherapy is largely dependent on the tumor microenvironment (TME). The high degree of heterogeneity within TME remains a major obstacle to acquire satisfactory therapeutic. Emerging studies suggest that gut microbiota is becoming an important regulator of TME. Polysaccharides as tumor immunotherapeutic agents or immune adjuvants not only exhibit antitumor activity by targeting gut microbiota, but also expand their role in the tumor immunotherapy by remodeling TME. To date, the mechanism by which polysaccharides targeting TME for tumor prevention via gut microbiota has not been deeply investigated. In this review, recent advances in the regulation of TME by polysaccharides through gut microbiota were systematically outlined, and the challenges and possible solutions in the clinical application of TME-targeted polysaccharides were discussed. Exploring the relationship between polysaccharides and TME from the perspective of gut microbiota may provide new ideas for the application of polysaccharides in tumor immunotherapy. This is a new area with major challenges that deserve further exploration.

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.

Updates on the Prevention and Management of Post-Polypectomy Bleeding in the Colon

Post-polypectomy bleeding (PPB) remains a significant procedure-related complication, with multiple risk factors determining the risk including patient demographics, polyp characteristics, endoscopist expertise, and techniques of polypectomy. Immediate PPB is usually treated promptly, but management of delayed PPB can be challenging. Cold snare polypectomy is the optimal technique for small sessile polyps with hot snare polypectomy for pedunculated and large sessile polyps. Topical hemostatic powders and gels are being investigated for the prevention and management of PPB. Further studies are needed to compare these topical agents with conventional therapy.

Potential of Direct Oral Anticoagulant in Bleeding After Gastric Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

An increasing number of patients are undergoing gastric endoscopic submucosal dissection (ESD) with active prescriptions of direct oral anticoagulants (DOACs). Only a few reports have described the effects of DOAC intake on postoperative bleeding. We aimed to investigate the bleeding risk associated with DOACs after gastric ESD.

METHODS

Clinical studies published up to April 2022 showing bleeding rates after gastric ESD in patients taking DOACs were identified using electronic searches. The primary outcome was the rate of bleeding after gastric ESD in patients receiving DOACs compared to those not receiving antithrombotic therapy. In this meta-analysis, odds ratios (ORs) were calculated and pooled using a random effects model. The secondary outcome was the difference in the bleeding rate between patients treated with DOACs and those treated with warfarin and antiplatelet drugs.

RESULTS

Seven studies were included in this meta-analysis. The pooled analysis showed that DOACs had a higher bleeding rate than non-thrombotic therapy (17.0% vs. 3.4%; OR 5.72; 95% confidence interval [CI], 4.33-7.54; I2 = 0%). The bleeding risk associated with DOAC administration was similar to that associated with warfarin (17.0% vs. 20.0%; OR 0.83; 95% CI 0.59-1.18; I2 = 0%), whereas it was higher than that associated with antiplatelet administration (16.9% vs. 11.0%; OR 1.63; 95% CI 1.14-2.34; I2 = 8%).

CONCLUSIONS

This meta-analysis reveals that the bleeding risk of DOACs is higher than that of non-antithrombotics and antiplatelets, whereas it is comparable to that of warfarin. Gastric ESD in patients on anticoagulants requires careful postoperative management.

Risk of delayed bleeding after colorectal endoscopic submucosal dissection: the Limoges Bleeding Score

BACKGROUND

Clinically significant delayed bleeding (CSDB) is a frequent, and sometimes severe, adverse event after colorectal endoscopic submucosal dissection (ESD). We evaluated risk factors of CSDB after colorectal ESD.

METHODS

We analyzed a prospective registry of 940 colorectal ESDs performed from 2013 to 2022. The incidence of bleeding was evaluated up to 30 days. Risk factors for delayed bleeding were evaluated by multivariate logistic regression. A Korean scoring model was tested, and a new risk-scoring model was developed and internally validated.

RESULTS

CSDB occurred in 75 patients (8.0%). The Korean score performed poorly in our cohort, with a receiver operating characteristic (ROC) curve of 0.567. In the multivariate analysis, risk factors were age ≥75 years (odds ratio [OR] 1.63; 95%CI 0.97-2.73; 1 point), use of antithrombotics (OR 1.72; 95%CI 1.01-2.94; 1 point), rectal location (OR 1.51; 95%CI 0.92-2.48; 1 point), size >50 mm (OR 3.67; 95%CI 2.02-7.14; 3 points), and American Society of Anesthesiologists (ASA) score of III or IV (OR 2.26; 95%CI 1.32-3.92; 2 points). The model showed fair calibration and good discrimination, with an area under the ROC curve of 0.751 (95%CI 0.690-0.812). The score was used to define two groups of patients, those with low-medium risk (0 to 4 points) and high risk (5 to 8 points) for CSDB (respective bleeding rates 4.1% and 17.5%).

CONCLUSION

A score based on five simple and meaningful variables was predictive of CSDB.

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).

Hemostatic Effect and Mechanism of Epidermal Growth Factor-Hemostatic Powder after Endoscopic Submucosal Dissection in a Porcine Model

BACKGROUND/AIMS

Among several methods used to prevent endoscopic submucosal dissection (ESD) bleeding, the recently developed hemostatic powder (HP) has few technical limitations and is relatively easy-to-use. This study aimed to analyze the hemostatic effects and mechanisms of two HPs using a porcine upper gastrointestinal hemorrhage model.

METHODS

We evaluated HPs (Endospray and epidermal growth factor [EGF]-endospray) for adhesion, waterproofing ability, permeability, and absorption in vitro. ESD was performed to induce bleeding ulcers in the porcine stomachs. In a total of three pigs, three bleeding ulcers per animal were generated. Hemostasis and rebleeding were evaluated endoscopically. After 72 hours, the animals were sacrificed, and histologically analyzed.

RESULTS

The water absorption of HPs was over 20 times the initial value within 30 minutes. The gelated HPs completely blocked water penetration into the applied site within 5 minutes and strongly adhered to the Petri-dish surface for up to 6 hours. The initial hemostasis rates within 5 minutes were 33.3%, 100.0%, and 66.7%, and the rebleeding rates at 6 to 72 hours after HP application were 33.3%, 16.7%, and 33.3% (control, Endospray, and EGF-endospray groups, respectively). Histological analysis revealed the thickness of the regenerated mucosa (522.1, 514.5, and 680.3 μm) and the submucosal layer (1,510.3, 2,848.2, and 3,062.3 μm) and the number of newly formed blood vessels (15.3, 17.9, and 20.5) in the control, Endospray, and EGF-endospray groups, respectively.

CONCLUSIONS

The endoscopic HPs demonstrated the ability to elicit effective initial hemostasis and the histological ulcer-healing effect of EGF in an animal model of hemorrhagic gastric ulcers.

Efficacy of local hemostatic agents after endoscopic submucosal dissection: a meta-analysis

INTRODUCTION

Topical hemostatic agents have been used to reduce bleeding rates after endoscopic submucosal dissection (ESD) for gastric cancer. However, to date, no review has summarized evidence on their efficacy.

MATERIAL AND METHODS

PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar were searched for studies comparing bleeding rates after ESD with and without local hemostatic agents.

RESULTS

Eleven studies were included. The studies used polyglycolic acid (PGA) sheets and fibrin glue, fibrin glue, oxidized regenerated cellulose, polysaccharide hemostatic powder, or polyethylene oxide adhesive. Meta-analysis revealed a statistically significant reduction in the risk of delayed bleeding with the use of PGA sheets & fibrin glue (six studies; RR: 0.35 95% CI: 0.20, 0.63 p = 0.0005). However, meta-analysis of two studies showed no difference in the risk of bleeding based on the use of fibrin glue (RR: 0.44 95% CI: 0.03, 7.17 p = 0.56). Scarce data were available for the remaining hemostatic agents.

CONCLUSION

A large number of different hemostatic agents have been used to reduce the risk of bleeding after ESD for gastric cancer. Observational studies indicate that the use of PGA with fibrin glue could reduce the risk of bleeding after ESD. However, evidence for other agents was too scarce to derive conclusions.

Endoscopic Delivery of Polymers Reduces Delayed Bleeding after Gastric Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis

New endoscopic approaches for the prevention of delayed bleeding (DB) after gastric endoscopic submucosal dissection (ESD) have been reported in recent years, and endoscopic delivery of biodegradable polymers for iatrogenic ulcer hemostasis and coverage has emerged as one of the most promising techniques for post-ESD management. However, the comparative efficacy of these techniques remains uncertain. We performed a systematic search of multiple databases up to May 2022 to identify studies reporting DB rates as outcomes in patients undergoing gastric ESD who were treated with subsequent endoscopic management, including endoscopic closure (clip-based methods and suturing), PGA sheet tissue shielding, and hemostatic powder/gel spray (including polymeric sealants and other adhesives). The risk ratios (RRs) of delayed bleeding in treatment groups and control groups were pooled, and the Bayesian framework was used to perform a network meta-analysis (NMA). Among these studies, 16 head-to-head comparisons that covered 2742 lesions were included in the NMA. Tissue shielding using PGA sheets significantly reduced the risk of DB by nearly two thirds in high-risk patients, while hemostatic spray systems, primarily polymer-based, reduced DB in low-risk patients nine-fold. Researchers should recognize the essential role of polymers in the management of ESD-induced ulcers, and develop and validate clinical application strategies for promising materials.

The future of endoscopic resection for early gastric cancer

Endoscopic resection for early gastric cancer is recommended when the risk of lymph node metastasis is negligible and should be performed through submucosal dissection due to well-established short- and long-term results. To overcome technical difficulties and decrease adverse events some techniques have been studied. This review outlines current strategies for improving patient selection and highlights innovative techniques that help minimize adverse events. Moreover, we discuss how to improve management after curative and noncurative resections.

Propensity score matching analysis to evaluate efficacy of polyethylene oxide adhesive on preventing delayed bleeding after gastric endoscopic submucosal dissection

Regardless of technical advancements, delayed bleeding is still a common adverse event after gastric endoscopic submucosal dissection (ESD), often occurring in the early postoperative phase. This study aimed to evaluate the efficacy of a newly designed polyethylene oxide (PEO) adhesive for preventing delayed gastric bleeding. Patients who underwent gastric ESD between December 2017 and December 2020 at three Chinese institutions were retrospectively reviewed. Patients receiving PEO application on gastric post-ESD ulcers were included in the PEO group, and patients without this procedure were included in the control group. To minimize potential bias, propensity score matching was performed, and sex, age, lesion size, lesion morphology, ulceration, localization, procedure time, frequency of major intraoperative bleeding, resected specimen size, lesion histopathology, submucosal invasion and the taking of antithrombotic drugs were included as matching factors. The incidence of delayed bleeding and time to bleeding were compared between both groups. After propensity score matching, 270 patients (135 per group) were included in the analysis. The delayed bleeding rate in the PEO group was significantly lower than that in the control group (1.5%, 2/135 vs. 8.9%, 12/135, P = 0.006). The median time (range) to bleeding was 4.5 (4–5) days in the PEO group and 2 (1–15) days in the control group, with no significant difference (P = 0. 198). PEO demonstrated a significant effect in reducing the rate of delayed bleeding. Further study is warranted to confirm the efficacy of PEO for bleeding that occurs in the early phase after gastric ESD.

Carbazochrome sodium sulfonate is not effective for prevention of post-gastric endoscopic submucosal dissection bleeding: A retrospective study

Background

Carbazochrome sodium sulfonate (CSS) is conventionally administered to prevent post-endoscopic submucosal dissection (ESD) bleeding in many institutions, but research on its preventive efficacy is lacking. Therefore, we investigated the risk of post-ESD bleeding and the preventive efficacy of CSS administration.

Methods

We retrospectively reviewed 304 lesions in 259 patients with gastric neoplasms who underwent ESD at Asahikawa Medical University Hospital from 2014 to 2021. In the CSS group, CSS 100 mg/day was intravenously infused with maintenance fluid replacement on postoperative days 0–2. The risk factors of post-ESD bleeding, including CSS administration, were investigated.

Results

The overall rate of post-ESD bleeding was 4.6% (14/304). The univariate analysis showed that atrial fibrillation (Af), warfarin intake, heparin replacement, and tumor location in the lower third were significant risk factors for increasing the likelihood of postoperative bleeding. In the multivariate analysis, Af (odds ratio [OR] 3.83, 95% CI 1.02–14.30; p < 0.05), heparin replacement (OR 4.60, 95% CI 1.02–20.70; p < 0.05), and tumor location in the lower third of the stomach (OR 6.67, 95% CI 1.43–31.00; p < 0.05) were independent factors for post-ESD bleeding. Post-ESD bleeding was observed in 5.2% (9/174) of the CSS group and 3.8% (5/130) of the non-CSS group, with no significant difference between the two groups (p = 0.783). Additionally, CSS was not shown to have preventive effects in groups with higher-risk factors, such as Af diagnosis, warfarin use, heparin replacement, and tumor location in the lower third of the stomach.

Conclusion

CSS administration was not effective for the prevention of the post-ESD bleeding in the overall patient population as well as in higher-risk patients. This suggests that the administration of CSS for post-ESD bleeding prevention may need to be reconsidered.

Strategies that Reduce Post-endoscopic Submucosal Dissection Bleeding

Bleeding after endoscopic submucosal dissection (ESD), one of the most common postprocedural adverse events, is the main cause of increased readmission rates and hospital costs. Generally, the incidence of post-ESD bleeding is estimated to be about 5%. However, the incidence of bleeding is particularly increased in high-risk patients. In particular, it has an incidence of over 50% in patients that use antithrombotic agents. The well-known risk factors for post-ESD bleeding include antithrombotic therapy, lesions in the proximal stomach, specimen size >4 cm, and concomitant renal disease. Currently, the number of patients at a high risk of post-ESD bleeding has been increasing. This may be due to the aging society and the increase in the usage of antithrombotic agents. Therefore, several strategies have been employed to prevent post-ESD bleeding. These strategies include acid inhibition therapy, preventive hemostasis using Doppler endoscopic ultrasound and artery-selective clipping, second look endoscopy, the closings method, and the shield methods. However, these methods are technically demanding, which hinders their wide usage in clinical practice. Recently, several hemostatic powders have been developed and clinically used in the treatment of gastrointestinal bleeding. In this article, we review the risk factors for post-ESD bleeding and the recently introduced prevention methods. Moreover, we aimed to explore realistic and appropriate strategies for the prevention of post-ESD bleeding.