Polysaccharide hemostatic system for hemostasis management in colorectal endoscopic mucosal resection

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.

Hemostatic powder for acute upper gastrointestinal bleeding: Recent research advances

Acute upper gastrointestinal bleeding (AUGIB) is a clinically common emergency condition. The common causes of AUGIB are peptic ulcer and esophagogastric variceal bleeding. Despite continuous improvements in endoscopic hemostasis techniques, endoscopic treatment is still unsuccessful in 5%-15% of patients. Hemostatic powder, a new drug for endoscopic hemostasis that is sprayed on the bleeding site with the assistance of an air pump, can absorb water to promote clotting substance aggregation and then adhere over the lesion, forming a mechanical barrier and then achieving hemostasis. It is convenient to spray hemostatic powder under endoscopy, where precise positioning is not warranted. The immediate hemostasis rate of hemostatic powder is often high, and it can be used as a remedy after the failure of conventional hemostasis. However, until now, there have been no recommendations in China regarding the use of hemostatic powder for the treatment of AUGIB. This article summarizes the mechanism, clinical applicability, and side effects of five major types of hemostatic powder by reviewing the existing evidence, with an aim to strengthen endoscopists' understanding of this drug.

A Comparative Study of the Resorption and Immune Response for Two Starch-Based Hemostat Powders

INTRODUCTION

Powder hemostats are valuable adjuncts to minimize intraoperative and postoperative complications. In addition to promotion of rapid coagulation, resorption, and biocompatibility are desirable attributes. Plant starch-based polysaccharide hemostat powders are effective and widely used hemostatic agents, however their source and/or processing can affect characteristics such as in vivo degradability. For example, Arista is a purified/hydrolyzed starch powder that is rapidly resorbed in vivo; whereas PerClot shows slow resorption and preservation of a crystalline form.

MATERIALS AND METHODS

In the present study, we compared the cellular response to the hemostatic agents PerClot and Arista both in vitro and in vivo, and used potato starch and urinary bladder extracellular matrix (UBM-ECM) as high crystallinity/slowly resorbable and prohealing controls, respectively.

RESULTS

All test articles and their degradation products were cytocompatible in vitro as measured by cell viability and metabolic activity of bone-marrow macrophages. PerClot induced a stronger proinflammatory, M1-like macrophage response in vitro (P < 0.001) than Arista, likely due to differences in source composition. Histologic examination of the in vivo surgical site showed the almost complete degradation of Arista after 12 h (day 0), whereas both PerClot and potato starch were still present at 28 d with crystals identifiable with polarized light microscopy and periodic acid Schiff (PAS) staining. Macrophage phenotype in vivo showed no differences between PerClot and Arista. Collagen deposition and mononuclear cell accumulation consistent with an early foreign body response were present around PerClot and potato starch crystals, whereas no such cell or connective tissue deposition was noted at the site of Arista or UBM-ECM placement.

Modification of the endoscopic hemostatic powder application technique

Video 1Modification of the endoscopic hemostatic powder application technique.

Prophylactic Clipping to Prevent Delayed Bleeding and Perforation After Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

To help prevent delayed adverse events after endoscopic surgery, endoscopists often place clips at the site. This meta-analysis aimed to assess the efficacy and safety of prophylactic clipping in the prevention of delayed bleeding and perforation after endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR).

METHODS

Multiple databases were searched from the inception dates to April 2021. And we included all relevant studies. Pooled odds ratio comparing the prophylactic clipped group versus nonprophylactic clipped group were calculated using the random effects model.

RESULTS

Twenty-seven articles fulfilled the inclusion criteria, with a total size of 8693 participants. There was statistically significant difference in prophylactic clipping versus no prophylactic clipping for delayed bleeding and perforation found in all studies (odds ratio: 0.35, 95% confidence interval: 0.25-0.49, P <0.01; odds ratio: 0.42, 95% confidence interval: 0.21-0.83, P <0.05; respectively). Besides, statistically significant difference was also found in subgroup analyses based on patients with lesions larger than 20 mm. Prophylactic clipping was more protective for duodenal delayed adverse events than colorectum. The use of clip closure was more protective to ESD-related delayed adverse events than EMR.

CONCLUSIONS

Prophylactic clipping after ESD and EMR was beneficial in preventing delayed bleeding and perforation.

Hemostatic powders for gastrointestinal bleeding: a review of old, new, and emerging agents in a rapidly advancing field

Background and study aims  Hemostatic powders are increasingly used to address limitations in conventional endoscopic techniques for gastrointestinal bleeding. Various agents exist with different compositions, characteristics, efficacy, and adverse events (AEs). We sought to review existing hemostatic powders, from preclinical to established agents. Methods  A literature review on hemostatic powders for gastrointestinal bleeding was undertaken through a MEDLINE search from 2000-2021 and hand searching of articles. Relevant literature was critically appraised and reviewed for mechanism of action, hemostasis and rebleeding rate, factors associated with hemostatic failure, and AEs. Results  The most established agents are TC-325 (Hemospray), EndoClot, and Ankaferd Blood Stopper (ABS). These agents have been successfully applied to a variety of upper and lower gastrointestinal bleeding etiologies, in the form of primary, combination, salvage, and bridging therapy. Few AEs have been reported, including visceral perforation, venous embolism, and self-limited abdominal pain. Newer agents include CEGP-003 and UI-EWD, which have shown results similar to those for the older agents in initial clinical studies. All aforementioned powders have high immediate hemostasis rates, particularly in scenarios not amenable to conventional endoscopic methods, but are limited by significant rates of rebleeding. Other treatments include TDM-621 (PuraStat) consisting of a liquid hemostatic agent newly applied to endoscopy and self-propelling thrombin powder (CounterFlow Powder), a preclinical but promising agent. Conclusions  Rapid development of hemostatic powders and growing clinical expertise has established these agents as a valuable strategy in gastrointestinal bleeding. Further research will continue to refine the efficacy and applicability of these agents.

Preventing Postendoscopic Mucosal Resection Bleeding of Large Nonpedunculated Colorectal Lesions

The most common major adverse event of endoscopic mucosal resection (EMR) is clinically significant post-EMR bleeding (CSPEB), with an incidence of 6%-7% in large lesions. Repeat colonoscopy, blood transfusions, or other interventions are often needed. The associated direct costs are much higher than those of an uncomplicated EMR. In this review, we discuss the aspects related to CSPEB of large nonpedunculated polyps, such as risk factors, predictive models, and prophylactic measures, and we highlight evidence for preventive treatment options and explore new methods for bleeding prophylaxis. We also provide recommendations for steps that can be taken before, during, and after EMR to minimize bleeding risk. Finally, this review proposes future directions to reduce CSPEB incidence.

A novel self-assembling peptide for hemostasis during endoscopic submucosal dissection: a randomized controlled trial

BACKGROUND

 Endoscopic submucosal dissection (ESD) is associated with a risk of bleeding. Bleeding is usually treated with diathermy, although this does carry a risk of mucosal thermal injury. Purastat is a topical hemostat that may be effective in controlling bleeding during ESD, thereby reducing the use of heat therapy. The aim of this study was to assess the reduction in heat therapy used in the interventional group (Purastat) compared with the control group. The secondary aims were to compare the procedure length, time for hemostasis, delayed bleeding rate, adverse events, and wound healing between the groups.

METHODS

 This was a single-center randomized controlled trial of 101 patients undergoing ESD. Participants were randomized to a control group where diathermy was used to control bleeding or an interventional group where Purastat could be used. Follow-up endoscopy was performed at 4 weeks to assess wound healing.

RESULTS

 There was a significant reduction in the use of heat therapy for intraprocedural hemostasis in the interventional group compared with controls (49.3 % vs. 99.6 %, P < 0.001). There were no significant differences in the procedure length, time for hemostasis, and delayed bleeding rate between the groups. Complete wound healing at 4 weeks was noted in 48.8 % of patients in the interventional group compared with 25.0 % of controls (P = 0.02).

CONCLUSIONS

 This study has demonstrated that Purastat is an effective hemostat that can reduce the need for heat therapy for bleeding during ESD. It may also have a role in improving post-resection wound healing.

Efficacy of a novel self-assembling peptide hemostatic gel as rescue therapy for refractory acute gastrointestinal bleeding

BACKGROUND

Acute gastrointestinal bleeding (AGIB) results in significant morbidity and mortality. Topical hemostatic products have been developed for endoscopic use to help in the management of difficult bleeding. Our aim was to demonstrate the ease of use, safety, and efficacy of PuraStat, a novel hemostat, to control AGIB.

METHODS

We describe 77 patients (41 men) who were treated for acute upper and lower AGIB in a 2-year period. In 50 patients, bleeding occurred as a complication of a previous endoscopic procedure, predominantly endoscopic mucosal resection (EMR) and endoscopic retrograde cholangiopancreatography (ERCP); however, in the other 27 patients, it derived from peptic ulcers, angiodysplasia, cancers, and surgical anastomoses. Bleeding was spurting in 13 of the 77 patients and oozing in 64. PuraStat was used after the failure of at least two conventional hemostatic methods.

RESULTS

A mean of 2.6 conventional hemostatic methods had been attempted prior to the application of PuraStat. PuraStat achieved successful hemostasis in 90.9 % of patients. In 41 patients, once hemostasis was obtained with PuraStat, endoscopists further stabilized hemostasis by using at least one additional method. Recurrence of bleeding was observed in eight patients (10.4 %). In 16 patients with intraprocedural bleeding, it was possible to complete the procedures (14 EMR, 2 ERCP) after PuraStat hemostasis. No adverse events related to PuraStat were recorded.

CONCLUSIONS

PuraStat is feasible, safe, and effective in controlling different types of gastrointestinal hemorrhage after failure of conventional hemostatic methods. Its application also does not hinder continuing endotherapy.

Novel hemostatic adhesive powder for nonvariceal upper gastrointestinal bleeding

Background and study aims  A new hemostatic adhesive powder (UI-EWD) was developed to reduce high rebleeding rates and technical challenges associated with application of currently available hemostatic powders. The aim of the current study was to assess performance of UI-EWD for nonvariceal upper gastrointestinal bleeding (NVUGIB). Patients and methods  A total of 56 consecutive patients that received UI-EWD monotherapy for endoscopic hemostasis due to NVUGIB were retrospectively reviewed. Main study outcomes were success rates with immediate hemostasis and rebleeding within 30 days. Outcomes were analyzed by reviewing patient medical records. Results  Etiologies of bleeding were: post-endoscopic therapy bleeding in 46 (82.1 %), peptic ulcer in 8 (14.3 %), tumor in 1 (1.8 %), and other in 1 (1.8 %). UI-EWD was successfully applied at bleeding site in all cases. The success rate of immediate hemostasis was 96.4 % (54/56), and the 30-day rebleeding rate among patients that achieved immediate hemostasis was 3.7 % (2/54). No adverse event related to use of UI-EWD occurred. Conclusion  UI-EWD was found to have a high immediate hemostasis success rate in NVUGIB when used as monotherapy and showed promising results in terms of preventing rebleeding.

Endoscopic Hemostasis for Non-Variceal Upper Gastrointestinal Bleeding: New Frontiers

Non-variceal upper gastrointestinal bleeding (NVUGIB) refers to blood loss from the gastrointestinal tract proximal to the ligament of Treitz due to lesions that are non-variceal in origin. The distinction of the bleeding source as non-variceal is important in numerous aspects, but none more so than endoscopic approaches for successful hemostasis. When a patient presents with acute overt blood loss, NVUGIB is a medical emergency, which requires immediate intervention. There have been major strides in pharmacologic and endoscopic interventions for successful induction and remission of hemostasis in the last two decades. Despite achieving tangible improvements, the burden of the disease and the consequent mortality remain high. To address endoscopic outcomes better, several new technologies have emerged and have been subsequently incorporated to the armamentarium of hemostatic tools. This study aims to provide a succinct review on novel technologies for endoscopic hemostasis.

Devices for endoscopic hemostasis of nonvariceal GI bleeding (with videos)

BACKGROUND

Endoscopic intervention is often the first line of therapy for GI nonvariceal bleeding. Although some of the devices and techniques used for this purpose have been well studied, others are relatively new, with few available outcomes data.

METHODS

In this document, we review devices and techniques for endoscopic treatment of nonvariceal GI bleeding, the evidence regarding their efficacy and safety, and financial considerations for their use.

RESULTS

Devices used for endoscopic hemostasis in the GI tract can be classified into injection devices (needles), thermal devices (multipolar/bipolar probes, hemostatic forceps, heater probe, argon plasma coagulation, radiofrequency ablation, and cryotherapy), mechanical devices (clips, suturing devices, banding devices, stents), and topical devices (hemostatic sprays).

CONCLUSIONS

Endoscopic evaluation and treatment remains a cornerstone in the management of nonvariceal upper- and lower-GI bleeding. A variety of devices is available for hemostasis of bleeding lesions in the GI tract. Other than injection therapy, which should not be used as monotherapy, there are few compelling data that strongly favor any one device over another. For endoscopists, the choice of a hemostatic device should depend on the type and location of the bleeding lesion, the availability of equipment and expertise, and the cost of the device.

Haemostasis and prevention of bleeding related to ER: The role of a novel self-assembling peptide

Background

Endoscopic resection is now commonly used for removal of early gastrointestinal lesions. However, the risk of the procedure may be heightened by intraprocedural or delayed bleeding. A novel, self-assembling peptide (PuraStat®) was recently licensed for use as a haemostat.

Objective

The aim of this study was to assess the efficacy and safety of this haemostat when used to control intraprocedural bleeding or to prevent delayed bleeding in endoscopic resection.

Methods

PuraStat® was used on 100 patients undergoing endoscopic resection in a tertiary referral centre. The efficacy, safety, feasibility of use and delayed bleeding rates were measured.

Results

Forty-eight oesophageal, 31 colorectal, 11 gastric and 10 duodenal procedures were included. The mean lesion size was 3.7 cm and 30% of the patients were on antithrombotic therapy. Intraprocedural bleeding occurred in 64%. PuraStat® was an effective haemostat in 75% of these cases. Only a small amount was required for haemostasis (mean = 1.76 ml) and it took on average 69.5 seconds to stop a bleed. The delayed bleeding rate was 3%.

Conclusions

PuraStat® is an effective haemostat for use in controlling bleeds during endoscopic resection. It is safe, easy to use and did not interfere with the procedure.

What Is the Best Endoscopic Strategy in Acute Non-variceal Gastrointestinal Bleeding?

OPINION STATEMENT

PURPOSE OF REVIEW: Upper non-variceal gastrointestinal bleeding (UNVGIB) remains an important clinical challenge for endoscopists, requiring skill and expertise for correct management. In this paper, we suggest the best strategy for an effective treatment of this complex category of patients.

RECENT FINDINGS

Early endoscopic examination, the increasingly widespread use of endoscopic hemostasis methods, and the most powerful antisecretory agents that induce clot stabilization have radically modified the clinical scenario for treating this pathology. While hospitalization for digestive hemorrhage is decreasing, the incidence of bleeding seems to be increasing, especially in the elderly for whom a greater use of gastrolesive drugs and the presence of comorbidities are more common. A multidisciplinary approach for initial patient evaluation and hemodynamic resuscitation prior to endoscopic treatment is crucial for correct management, prevention of rebleeding, and reduction of morbidity and mortality rates and hospital stays. Appropriate operator technical expertise, together with the availability of a wide range of endoscopes and devices, is mandatory. Newer endoscopic techniques may improve patient outcomes for difficult-to-treat lesions. Today, endoscopic hemostasis can be achieved in over 95% of patients.

Role of hemostatic powders in the management of lower gastrointestinal bleeding: A review

Despite the recent advances in endoscopic hemostatic techniques, the management of lower gastrointestinal bleeding could be sometimes challenging. Hemostatic powders such as Hemospray, EndoClot, and Ankaferd Blood Stopper have found their way into digestive endoscopy and are licenced in many countries especially for use in upper gastrointestinal bleeding. We reviewed the literature on the use of these hemostatic powders in different situations in lower gastrointestinal bleeding and looked at the success rate and rebleeding rate. Most of the data are derived from case reports, retrospective and prospective case series with absence of any randomized controlled trials. Hemostatic powders were used as primary or salvage therapy to control bleeding from polypectomy site, colonic tumors, diverticula, arteriovenous malformations, radiation proctitis, ischemic colitis, and surgical intestinal anastomosis. The rate of immediate control of bleeding is in the range of 88-100% with a recurrence rate of 3-13% except for radiation proctitis bleeding where rebleeding rate can be as high as 77%. Although there are many advantages for the use of local hemostatic agents in lower gastrointestinal bleeding, future randomized controlled trials comparing them with conventional methods are needed.

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.

Hemostatic powder application for control of acute upper gastrointestinal bleeding in patients with gastric malignancy

BACKGROUND AND STUDY AIMS

Despite use of various endoscopic therapies in patients with tumor-related bleeding, various rates of successful immediate hemostasis and short-term rebleeding have been reported. We aimed to evaluate preliminary results of use of the EndoClot polysaccharide hemostatic system (PHS) in patients with acute upper gastrointestinal bleeding (UGIB) from a gastric malignancy.

PATIENTS AND METHODS

We retrospectively analyzed data from a prospectively collected database of 12 patients with acute UGIB from a gastric malignancy who had been treated with EndoClot PHS. The EndoClot air compressor was used to propel 2 g of absorbable modified polymer particles onto the bleeding site. We checked successful immediate hemostasis, rebleeding events and mortality within 30 days.

RESULTS

Twelve patients were enrolled in the study. The median patient age was 72.5 years (range, 57 - 89). The initial median hemoglobin level was 6.75 g/dL (range, 5.4 - 8.9). The median systolic blood pressure was 114 mmHg (range, 86 - 153). Eleven patients had advanced gastric cancer and one patient had a gastrointestinal stromal tumor. The lower body of the stomach was the most common tumor location (58.3 %), and the median tumor size was 40 mm (range, 15 - 100). Immediate hemostasis was achieved in all patients, and rebleeding developed in 2 of 12 patients (16 %), 3 and 5 days after treatment. There were no significant Endoclot PHS-related adverse events, and there was no all-cause mortality at 30 days after the intervention.

CONCLUSIONS

Endoclot PHS represents a new alternative, complementary, and promising therapy for patients with an acute UGIB from a gastric malignancy.

EndoClot Polysaccharide Hemostatic System in Nonvariceal Gastrointestinal Bleeding: Results of a Prospective Multicenter Observational Pilot Study

BACKGROUND AND STUDY AIMS

Hemostatic powders have been introduced to improve the management of gastrointestinal (GI) bleeding and to extend the variety of tools available for emergency endoscopy. The aim of the present pilot study was to evaluate the indication profiles and the short-term outcome of EndoClot.

PATIENTS, MATERIALS AND METHODS

In a prospective observational pilot study patients with acute nonvariceal GI bleeding were included. Primary or secondary application of EndoClot was assessed. Hemoglobin, prothrombine time and platelets were documented before and after hemostasis. The efficacy of EndoClot was assessed 72 hours and 1 week after application.

RESULTS

Seventy patients with acute GI bleeding were recruited into the study. Eighty-three percent (58/70) of the patients had upper and 17% (12/70) had lower GI bleeding. In the upper GI tract treatment success was achieved in 64% (30/47, 95% confidence interval, 50%-76%) after primary use and in all patients, when used after established techniques had failed (95% confidence interval, 70%-100%). In lower GI bleeding hemostasis was achieved in 83% of cases (10/12, 95% confidence interval 54%-97%). Rebleeding occurred in 11% (8/70), in 10% EndoClot served as a bridge to surgery (7/70).

CONCLUSIONS

EndoClot expanded the therapeutic options in the management of GI bleeding. It was applicable as a monotherapy or in combination with other techniques from oozing bleeding type or lower. It was most effective in diffuse or extensive bleeding activity or when access to the bleeding vessel was difficult. EndoClot can be applied as a bridge to surgery when classical methods of hemostasis have failed.

New Endoscopic Technologies and Procedural Advances for Endoscopic Hemostasis

Endoscopic interventions are first-line therapy for upper and lower gastrointestinal bleeding. Injection therapy in combination with a second endoscopic modality has reduced re-bleeding, need for surgery and mortality in non-variceal bleeding. For variceal bleeding endoscopic banding or cyanoacrylate injection techniques are recommended interventions. However, despite ease of application and general acceptance of these techniques, there is an ongoing re-bleeding rate associated with significant in-hospital mortality. We discuss current literature on new advances in endoscopic technologies and procedural techniques that have emerged to improve patient outcomes.

ACG Clinical Guideline: Management of Patients With Acute Lower Gastrointestinal Bleeding

This guideline provides recommendations for the management of patients with acute overt lower gastrointestinal bleeding. Hemodynamic status should be initially assessed with intravascular volume resuscitation started as needed. Risk stratification based on clinical parameters should be performed to help distinguish patients at high- and low-risk of adverse outcomes. Hematochezia associated with hemodynamic instability may be indicative of an upper gastrointestinal (GI) bleeding source and thus warrants an upper endoscopy. In the majority of patients, colonoscopy should be the initial diagnostic procedure and should be performed within 24 h of patient presentation after adequate colon preparation. Endoscopic hemostasis therapy should be provided to patients with high-risk endoscopic stigmata of bleeding including active bleeding, non-bleeding visible vessel, or adherent clot. The endoscopic hemostasis modality used (mechanical, thermal, injection, or combination) is most often guided by the etiology of bleeding, access to the bleeding site, and endoscopist experience with the various hemostasis modalities. Repeat colonoscopy, with endoscopic hemostasis performed if indicated, should be considered for patients with evidence of recurrent bleeding. Radiographic interventions (tagged red blood cell scintigraphy, computed tomographic angiography, and angiography) should be considered in high-risk patients with ongoing bleeding who do not respond adequately to resuscitation and who are unlikely to tolerate bowel preparation and colonoscopy. Strategies to prevent recurrent bleeding should be considered. Nonsteroidal anti-inflammatory drug use should be avoided in patients with a history of acute lower GI bleeding, particularly if secondary to diverticulosis or angioectasia. Patients with established high-risk cardiovascular disease should not stop aspirin therapy (secondary prophylaxis) in the setting of lower GI bleeding. [corrected]. The exact timing depends on the severity of bleeding, perceived adequacy of hemostasis, and the risk of a thromboembolic event. Surgery for the prevention of recurrent lower gastrointestinal bleeding should be individualized, and the source of bleeding should be carefully localized before resection.

[Endoscopic management of lower gastrointestinal bleeding]

Endoscopic hemostasis is the daily challenge that must be mastered by gastroenterologists. An emergency colonoscopy is the procedure of choice for lower gastrointestinal bleeding because of the diagnostic and therapeutic potential. Colonoscopy should be performed after oral preparation with 4-6 l polyethylene glycol solution within 12 h. In the case of massive hematochezia, colonoscopy without oral preparation employinga mechanical pump is possible and is not associated with a higher rate of complications. Many different endoscopic techniques are available (injection therapy, hemoclips, thermal coagulation, topical hemostatic substances). The suitable and most effective method must be chosen depending on the source of bleeding.

Improved Techniques for Endoscopic Mucosal Resection (EMR) in Colorectal Adenoma

Background

Endoscopic therapy of colorectal adenomas and early cancers is a standard method. Besides oncological criteria, the method is limited by polyp location, size, and texture.

Method

Based on the current literature, technical modifications and developments in endoscopic mucosal resection are described.

Results

Numerous approaches exist to improve the conditions of resection, including optimisation of mucosal elevation and modification of techniques, tools, and devices.

Conclusion

Endoscopic therapy of sessile and flat colorectal polyps remains a challenge. Some of the presented modifications can help to address this challenge.

Hemostatic Powders in Gastrointestinal Bleeding: A Systematic Review

Topical hemostatic agents and powders are an emerging modality in the endoscopic management of upper and lower gastrointestinal bleeding. This systematic review demonstrates the effectiveness and safety of these agents with special emphasis on TC-325 and Ankaferd Blood Stopper. The unique noncontact/nontraumatic application, ability to cover large areas of bleed, and ease of use make these hemostatic agents an attractive option in certain clinical situations, such as massive bleeding with poor visualization, salvage therapy, and diffuse bleeding from luminal malignancies.

Endoscopic application of polysaccharide powder for hemostasis in anticoagulated pigs (with video)

BACKGROUND

Acute GI bleeding remains a clinical problem of daily importance. Increasing numbers of patients with compromised coagulation challenge the established methods of endoscopic hemostasis. Therefore, new powders for the treatment of GI bleeding have been developed.

OBJECTIVE

To clarify the efficacy of a newly available anticoagulant powder in stopping hemorrhage.

DESIGN

A randomized prospective comparative study regarding the potential of an endoscopically applicable polysaccharide powder in pigs receiving antithrombotic medication.

SETTING

A professional veterinary animal laboratory.

PATIENTS

Twenty-two pigs were anticoagulated with heparin (n = 8), aspirin (n = 8), or no antithrombotic medication (n = 6), in a randomized order.

INTERVENTIONS

A bleeding ulcer with continuous bleeding (Forrest I b) was established in the stomach. Endoscopic hemostasis was performed using the powder.

MAIN OUTCOME MEASUREMENTS

Time to hemostasis and the amount of powder used were recorded. Follow-up occurred for 3 days, final hemoglobin measurement, followed by autopsy with control for post-interventional bleeding.

RESULTS

Endoscopic hemostasis was successful in all cases. Post-interventional bleeding was not recorded.

LIMITATIONS

Animal study, artificial superficial bleeding source.

CONCLUSION

Polysaccharide powder is able to stop active bleeding from Forrest I b lesions in pigs receiving antithrombotic therapy.

New and emerging endoscopic haemostasis techniques

Endoscopic treatment has been accepted as first-line treatment of upper gastrointestinal bleeding, both for variceal as well as for non-variceal haemorrhage. Dual modality treatment including injection therapy with mechanical or thermal haemostatic techniques has shown superior outcome compared with injection monotherapy in non-variceal bleeding. During recent years, new endoscopic devices have been developed and existing endoscopic techniques have been adapted to facilitate primary control of bleeding or achieve haemostasis in refractory haemorrhage. For mechanical haemostasis, larger, rotatable and repositionable clips have been developed; multiple-preloaded clips are also available now. Over the scope clips allow to ligate larger vessels and can close ulcer defects up to 20 mm. Topical, easily applied substances withdraw fluid from the blood and thereby initiate blood clotting. This can be helpful in diffuse oozing bleeding, for example, from tumour or hypertensive gastropathy and has also shown promising results in variceal and arterial bleeding as bridging before definitive treatment is available. Radiofrequency ablation and multiband ligation have emerged as new tools in the endoscopic management of gastric antral vascular ectasia. In acute refractory variceal bleeding, a covered and removable oesophagus stent can provide tamponade and gain time for transport to an interventional endoscopic centre or for radiological intervention such as TIPS.

Developments in flexible endoscopic surgery: a review

Flexible endoscopy is increasingly developing into a therapeutic instead of a purely diagnostic discipline. Improved visualization makes early lesions easily detectable and allows us to decide ad hoc on the required treatment. Deep enteroscopy allows the exploration of even the small bowel - for long a "white spot" for gastrointestinal endoscopy - and to perform direct treatment. Endoscopic submucosal dissection is a considerable step forward in oncologically correct endoscopic treatment of (early) malignant lesions. Though still technically challenging, it is increasingly facilitated by new manipulation techniques and tools that are being steadily optimized. Closure of wall defects and hemostasis could be improved significantly. Even the anatomy beyond the gastrointestinal wall is being explored by the therapeutic use of endoluminal ultrasound. Endosonographic-guided surgery is not only a suitable fallback solution if conventional endoscopic retrograde cholangiopancreatography fails, but even makes necrosectomy procedures, abscess drainage, and neurolysis feasible for the endoscopist. Newly developed endoscopic approaches aim at formerly distinctive surgical domains like gastroesophageal reflux disease, appendicitis, and cholecystitis. Combined endoscopic/laparoscopic interventional techniques could become the harbingers of natural orifice transluminal endoscopic surgery, whereas pure natural orifice transluminal endoscopic surgery is currently still in its beginnings.

Endoscopic haemostasis: an overview of procedures and clinical scenarios

Acute gastrointestinal bleeding is among the most urgent situations in daily gastroenterological practise. Endoscopy plays a key role in the diagnosis and treatment of such cases. Endoscopic haemostasis is probably the most important technical challenge that must be mastered by gastroenterologists. It is essential for both the management of acute gastrointestinal haemorrhage and the prevention of bleeding during high-risk endoscopic procedures. During the last decade, endoscopic haemostasis techniques and tools have grown in parallel with the number of devices available for endotherapy. Haemostatic powders, over-the-scope clips, haemostatic forceps, and other emerging technologies have changed daily practise and complement the standard available armamentarium (injectable, thermal, and mechanical therapy). Although there is a lack of strong evidence-based information on these procedures because of the difficulty in designing statistically powerful trials on this topic, physicians must be aware of all available devices to be able to choose the best haemostatic tool for the most effective procedure. We herein present an overview of procedures and clinical scenarios to optimise the management of gastrointestinal bleeding in daily practise.

New and emerging endoscopic therapies for gastrointestinal bleeding

PURPOSE OF REVIEW

To highlight the most recent findings and results of new hemostatic agents for acute bleeding of the gastrointestinal tract of common and less common cause published in the past 12 months.

RECENT FINDINGS

New hemostatic agents have been tested and emerged as promising therapies for acute upper and lower gastrointestinal bleeding. These are hemostatic sprays, stents for variceal tamponade and devices for mechanical closure of the gut wall.

SUMMARY

Some of these devices are capable to definitively stop a bleeding, others are used as adjuvant to other techniques as bridge to other definitive treatments. All these devices have been tested recently; therefore, more trials are needed to better establish their efficacy and safety.

Role of hemostatic powders in the endoscopic management of gastrointestinal bleeding

Acute gastrointestinal bleeding (AGIB) is a prevalent condition with significant influence on healthcare costs. Endoscopy is essential for the management of AGIB with a pivotal role in diagnosis, risk stratification and management. Recently, hemostatic powders have been added to our endoscopic armamentarium to treat gastrointestinal (GI) bleeding. These substances are intended to control active bleeding by delivering a powdered product over the bleeding site that forms a solid matrix with a tamponade function. Local activation of platelet aggregation and coagulation cascade may be also boosted. There are currently three powders commercially available: hemostatic agent TC-325 (Hemospray^®), EndoClot™ polysaccharide hemostatic system, and Ankaferd Bloodstopper^®. Although the available evidence is based on short series of cases and there is no randomized controlled trial yet, these powders seem to be effective in controlling GI bleeding from a variety of origins with a very favorable side effects profile. They can be used either as a primary therapy or a second-line treatment, and they seem to be especially indicated in cases of cancer-related bleeding and lesions with difficult access. In this review, we will comment on the mechanism of action, efficacy, safety and technical challenges of the use of powders in several clinical scenarios and we will try to define the main current indications of use and propose new lines of research in this area.

Highlights of international digestive endoscopy network 2013

Rapid advances in the technology of gastrointestinal endoscopy as well as the evolution of science have made it necessary for us to continue update in either various endoscopic techniques or state of art lectures relevant to endoscopy. International Digestive Endoscopy Network (IDEN) 2013 was held in conjunction with Korea-Japan Joint Symposium on Gastrointestinal Endoscopy (KJSGE) during June 8 to 9, 2013 at Seoul, Korea. Two days of impressive scientific program dealt with a wide variety of basic concerns from upper gastrointestine (GI), lower GI, pancreaticobiliary endoscopy to advanced knowledge including endoscopic submucosal dissection forum. IDEN seems to be an excellent opportunity to exchange advanced information of the latest issues on endoscopy with experts from around the world. In this special issue of Clinical Endoscopy, we prepared state of art review articles from contributing authors and the current highlights will skillfully deal with very hot spots of each KJSGE, upper GI, lower GI, and pancreaticobiliary sessions by associated editors of Clinical Endoscopy.