Endoscopic Interpretation and Therapy of Severe Lower Gastrointestinal Bleeding. Lower gastrointestinal bleeding is common, resulting in approximately 25 hospitalizations per 100,000 adults annually and accounting for an estimated 30% of all major gastrointestinal bleeding. It is more common in the elderly, and its presentation can range from trivial bleeding to massive life-threatening hemorrhage with a reported 5% mortality rate. Acute severe lower gastrointestinal bleeding is defined as bleeding that is of recent duration, is associated with clinical instability as measured by vital signs, anemia, and blood transfusion requirements, and emanates from a source between the ligament of trites and the anus. Various factors, including the suspected etiology, location, and rapidity of bleeding, time of admission, and center experience impact the choices for radiologic, surgical, or endoscopic diagnosis and treatment approaches. Historically, technetium scans have been used in many centers to confirm active bleeding and to localize the bleeding site in order to direct further angiographic or surgical intervention. Literature dating since 1990, however, suggests that technetium scans are not particularly useful. In positive scans, a bleeding site is confirmed in 1 half to 3 quarters of patients and correctly localized in less than half of the cases when compared to angiography or surgery. Furthermore, of the patients with a positive bleeding scan, less than half of the patients actually then underwent angiography, and fewer than half of the patients had positive angiographic findings. Angiography techniques have been modified over time to use smaller 5 to 7 French catheters for coiling or gel foam embolization. Using this optimal embolization technique, 12 published small studies have shown high rates of successful primary hemostasis in patients with active bleeding. Short term, less than one week, re-bleeding rates were, however, high, found to be about 25%. And data on long term re-bleeding rates is lacking. Ischemia was notably reported in close to 20% of patients, despite the use of smaller catheters and more directed therapy. Most ischemia was minor. However, major ischemia requiring further intervention was non-trivially present in about 7% of these series. Other complications related to angiography include contrast reactions, contrast nephropathy, and catheter-related arterial thrombosis or laceration. This is often due to the multiple injections that are required. For example, multiple arterial injections of the celiac, superior mesenteric, inferior mesenteric, and iliac arteries were performed in this patient with severe lower gastrointestinal bleeding. A blush in the superior rectal artery of the internal iliac was finally identified. The distal location made angiographic intervention challenging. Endoscopic evaluation was performed, and a rectal dolophoid lesion was band ligated. Whenever possible, it is preferable to perform surgery on an elective basis rather than emergently. Operative mortality is 10%, even with accurate localization, and up to 57% with blind subtotal colectomy. The role of urgent colonoscopy remains unclear in patients with lower gastrointestinal bleeding. Similar to upper gastrointestinal bleeding, approximately 80% of cases of lower GI bleed cease spontaneously. In addition, patients with lower GI bleeding present less frequently with shock and have lower transfusion requirements. Furthermore, there has been reluctance to perform colonoscopy urgently due to poor visibility, potential for complications, and theoretical concern about the adverse effects of purging the colon in the setting of active GI bleeding. Studies of urgent colonoscopy in the diagnosis and management of lower gastrointestinal bleeding are limited, using older technologies and techniques. Nevertheless, in the few small, mainly retrospective published series, urgent colonoscopy in patients who have acute lower GI bleeding has been shown to be safe and have a high diagnostic yield. The bleeding site was identified in close to 90% of cases. And endoscopic therapy was run in about 13%, with reported low complication rates. Overall, the length of hospital stay was shortened. More prospective studies are encouraged. The purpose of this educational DVD is to focus on the art and science of the endoscopic management of patients with acute severe lower gastrointestinal bleeding. Based on the literature and our experience, we will present the endoscopic diagnosis and treatment of lower gastrointestinal bleeding. We will first provide a comprehensive, illustrative differential diagnosis, and then show the components of successful endoscopic therapy, beginning with patient stratification and preparation, proper endoscope and equipment selection, and endoscopic therapy techniques through specific examples. Bleeding from colonic diverticula is the most common etiology of acute lower GI bleeding. Important historical questions should be asked to help aid in making a correct diagnosis. Focusing on age, comorbid conditions, NSAID use, radiation exposure, abdominal surgical history, and anorectal trauma. For example, in patients with lower GI bleeding over the age of 60, diverticular bleeding, arterial venous malformations, or ischemic colitis are most common, while in younger patients, infectious or inflammatory conditions are more likely. Comorbidities are at an increased risk for vascular ectasia. Abdominal radiation history is associated with radiation proctopathy. An upper gastrointestinal bleeding source must also be considered, as is in this case of an actively bleeding NSAID-related pyloric ulcer. Complete patient inspection from the mouth, such as the oral ulcers manifested in this patient with a Crohn's disease flare, to the anus, as in this case of an anal cancer, provides information to aid in the diagnosis. Diverticulosis remains the most frequent cause of lower GI bleeding and presents as acute painless hematochesia. Diverticula are located in the colonic wall at the sites of penetrating nutrient vessels. Bleeding is arterial and can occur either at the dome or the neck of the diverticulum. It is important to recognize the various stigmata of diverticular bleeding, including large and small vessels, adherent clot, flat pigmented spot, and erosion. The following cases illustrate the various stigmata. An actively bleeding vessel can be seen at the neck of this diverticulum and confirmed with washing. A non-bleeding visible vessel is seen at the dome of this wide-based diverticulum. Upon further examination of this actively bleeding diverticulum, a collection of small bleeding vessels was seen. Use of the CAP device facilitated further visualization. A clot is seen at the dome of this wide-based diverticulum. Despite extensive washing, the clot remained adherent. A flat pigmented spot is visualized at the neck of this diverticulum. Initially, attention was drawn to the area due to the clot. Careful inspection of this diverticulum with extensive washing showed multiple erosion surrounding its neck. Colitis accounts for about 15% of lower GI bleeding. Ischemic colitis, resulting from a sudden, often temporary reduction in mesenteric blood flow, is most common cause. It is usually associated with sudden onset abdominal pain. A large, single, linear ulcer running along the longitudinal axis of the colon, as seen here, is a classic endoscopic appearance of ischemic colitis. Most cases are self-limiting. Some infectious colitides may cause bleeding. Active bleeding can be seen from the pseudomembranes of this patient with Clostridium difficile colitis. Multiple discreet, deep ulcers are seen in this immunocompromised patient who presented with hematochesia. The histopathology specimens obtained from deep biopsies from the center of the ulcerations show viral inclusion bodies of cytomegalovirus. Multiple small ulcerations with nodular elevations containing amoebas, necrotic cells, and inflammatory debris with normal intravenous mucosa is seen in this case of amoebic colitis. Lower gastrointestinal bleeding may be a presentation or a flare of inflammatory colitis. Continuous, friable, inflamed mucosa can be seen in this case of ulcerative colitis. Severe active Crohn's colitis is shown in this case with long, vaguely serpiginous, parallel ulcerations, and jagged mucosa. Ulceration, friability, and telangiectasias are endoscopically apparent in this patient with a history of radiation exposure for prostate cancer. Diversion colitis occurs in a previously normal segment of colon after it has been surgically diverted from the fecal stream. Most diversion colitis is asymptomatic and is only discovered prior to restoration surgery. This patient, who had a colostomy for recurrent diverticulitis, however, presented with severe rectal bleeding from the Hartman pouch. Neoplasms account for about 13% of liver Neoplasms account for about 13% of lower GI bleeding. Most colorectal adenomas do not cause severe bleeding until they become cancerous, such as in this case of an invasive rectosigmoid cancer hemorrhage that presented with bright red rectal bleeding. Active bleeding can be seen at a polypectomy site in the rectosigmoid colon. With continuous washing, a visible vessel can be seen at the periphery of the resection site. Arterial venous malformations, also referred to as angio dysplasias and vascular ectasias, account for approximately 10% of lower GI bleeding. The dilated branch-like capillaries of the AVM can be readily visible here in the cecum. Active bleeding from an AVM in the cecum can be visualized with continuous washing. The markedly red center composed of dilated capillaries branching into the surrounding area are a classic endoscopic appearance. Anorectal disease, including hemorrhoids, anal fissures, and malignancies account for about 10% of lower gastrointestinal bleeding. Internal hemorrhoids are a common problem and are usually asymptomatic. Patients with symptomatic hemorrhoids may present with rectal bleeding. Dilated venous plexus with prominent capillaries and hyperemia can be appreciated in this patient with such symptoms. A solitary rectal ulcer with a visible vessel is identified in this patient presenting with hematokesia. A mass was appreciated on a digital rectal examination in this patient who presented with rectal bleeding. Active bleeding is seen from a rectal doliphoid lesion. Water immersion confirms the bleeding. Impressively large dilated submucosal veins in the rectum are seen in this patient with cirrhosis. In general, the approach to lower gastrointestinal bleeding is controversial and not yet standardized. The following video segments will demonstrate our technique of urgent colonoscopy to diagnose and treat lower gastrointestinal bleeding. We will describe an approach that encompasses patient stratification and preparation and proper endoscope and equipment selection. Through specific examples, we will show our endoscopic therapeutic techniques. The prognosis in lower GI bleeding varies, and most acute bleeding is self-limiting. As such, urgent colonoscopy should be targeted for patients with severe bleeding. Data are available to aid in the early identification of high-risk patients in order to allow more selective delivery of urgent interventions to the patients who will most likely benefit. Two recent studies have evaluated various presenting factors associated with predicting outcomes. Independent correlates of severe bleeding included ongoing bleeding, vital sign instability, syncope, non-tender abdominal exam, aspirin use, and more than two comorbid conditions. In general, patients with stable vital signs, no recent bloody affluent, and no syncope have a low risk of continued bleeding. An elective colonoscopy is appropriate. The risk of bleeding in patients with any risk factor is moderate to high, and such patients should undergo preparation for urgent colonoscopy. Nasogastric tube placement with gastric lavage should be strongly considered in the setting of acute lower GI bleeding to exclude an upper GI source. A positive aspirate should prompt emergent upper endoscopy. Upper endoscopy should also be performed in patients after a colonoscopy in cases where a colonic source is not identified. The nasogastric tube can be left in place for rapid purge bowel preparation. Once the patient has been resuscitated, the severity of the acuity of bleeding assessed and an upper gastrointestinal bleeding source is excluded, urgent colonoscopy should be performed. In cases of continued bleeding not amenable to endoscopic therapy, angiography or surgery should be considered. Rapid purge is best accomplished with polyethylene glycol-based solutions such as Golightly, Nulightly, or Colite. It should be administered by a nasogastric tube or by drinking one liter every 30 to 45 minutes. A median dose of 5 and 1 half liters, ranging between 4 and 14 liters, and three to four hours are required to cleanse the colon. Metoclopramide 10 milligrams IV prior to starting the purge has been recommended to control nausea and promote gastric emptying. Nasogastric suction immediately prior to colonoscopy is recommended if there is concern of large residual or need for deep sedation. Patients with known bowel obstruction or gastroparesis should not receive rapid purge preparation. Endoscope selection is an important step in the management of lower gastrointestinal bleeding. An adult colonoscope or an upper therapeutic endoscope with foot pedal water jet capabilities are needed. In cases of suspected small bowel bleeding, a therapeutic endoscope should be available. The emergency travel cart should have a foot-controlled water irrigation device, as shown. This enables cleaning of the mucosal surface with a strong water jet so that the site of bleeding can be identified precisely. Translucent cap devices should be easily accessible in the setting of lower GI bleeding as they may facilitate both diagnosis and treatment. These include the clear EMR cap or a translucent cap used for band ligation. The importance of the water irrigation device is illustrated in the following examples. In this case of diverticular bleeding, a strong water jet is key to allow efficient washing of the diverticula in the search for the bleeding site. In this case of a post-polypectomy bleed, a large clot is visualized at the prior resection site. With continuous washing and suction of the clot, it is dislodged and an actively bleeding visible vessel can be seen. In this case, active diverticular bleeding can clearly be appreciated. However, the exact bleeding site could not be precisely identified and was thought to be inside the diverticulum. Access to the site to apply direct therapy would be difficult and potentially dangerous as the clip span is wider than the neck of the diverticulum. The cap was used in this case to avert the diverticulum into the cap with light suction, gain access to the bleeding site, and apply endoscopic therapy. In the treatment of lower gastrointestinal bleeding, various endoscopic therapies used alone and in combination have been reported to be safe and efficacious. We will show the various endoscopic techniques, including clipping, looping, banding, argon plasma coagulation, and thermal therapies in the treatment of the different etiologies of lower GI bleeding. Familiarity with the different techniques is encouraged. In cases when endoscopic therapy is not rendered, it is still important to mark the location of the bleeding site for further intervention with angiography or surgery. Endoscopic marking can be accomplished with the use of radio-opaque clips or India ink that can be visualized during surgery. The following section will demonstrate various examples of the different endoscopic treatment modalities in lower GI bleeding. There are times even when more than one treatment is needed. This case of AVM bleeding shows initially that argon plasma therapy was used. Bleeding nonetheless continued, and endoscopic clipping was necessary. Multiple clips were required to achieve primary hemostasis. On follow-up, the patient had no report of re-bleeding. Available data suggests that endoscopic intervention for diverticular hemorrhage is safe and efficacious in certain cases. Injection therapy, shown here, to treat bleeding at the neck of a diverticulum has been reported with limited success. Due to the lack of muscularis propria at the dome of the diverticulum, therapy at this site using injection or thermal coagulation must be carefully considered. When surveying the colon for the source of the diverticular bleed, it is often difficult to relocate the bleeding site following initial identification. We recommend using an endoscopic clip for marking in order to ensure future endoscopic identification, as well as localization for future radiologic or surgical interventions if necessary. Direct clip application should be applied if a clear bleeding site is visualized. In this case, an actively bleeding large vessel is clearly identified at the neck of the diverticulum. After initially marking the location, direct clip therapy is applied. The clip is carefully positioned near the base of the artery in order to entrap the immediately surrounding tissue. The usefulness of the water jet is emphasized for precise clip application. Slight downward pressure is applied, the lumen is collapsed with minimal suction, and the clip is deployed. Although a single clip may be sufficient, we typically place two additional clips in order to ligate the feeding vessel proximally and distally to the bleeding point. This case demonstrates direct clip application to the dome of the diverticulum. An adherent clot is directly visualized in the diverticular dome. Bringing the clip close to the endoscope provides the most controlled technique. The clip is carefully positioned close to the vessel in order to entrap the immediately surrounding tissue, being cognizant of the thin diverticular wall. A second clip is placed at the opposite side of the defect in order to ensure hemostasis. There are times when the active diverticular bleeding site is not easily identified or the clip width span is not safe to enter the diverticulum. In these cases, the use of the CAP is helpful. The CAP device enables aversion of the diverticulum and permits further visualization of the bleeding site with slight suctioning. Precise, directed clip application and deployment can then be performed. Similar to the aversion method of the CAP technique, others have advocated the therapeutic concept of plication using band ligation and diverticular bleeding. In this case, the diverticulum is slightly suctioned into the CAP, being careful to avoid a complete red out. The band was released with no evidence of perforation. Severe bleeding was caused by a metastatic rectal cancer. Argon plasma coagulation therapy was used. The catheter probe is positioned close to the endoscope and just above, but not touching the mucosa of interest. In a controlled, steady fashion, short bursts of argon at a setting of 1.2 liters per minute and power of 60 watts was applied to the friable, diseased mucosa. The endoscopic appearance is improved following repeated applications of the therapy to the diseased mucosa. A number of techniques have been described in the treatment of arterial venous malformations. Generally, AVMs are treated when the patient is anemic or there is active bleeding. AVMs are treated when the patient is in a state of active bleeding. AVMs tend to be right-sided, where the colon wall is notably thinner. Use of mechanical hemostasis using endoscopic clips is shown in the treatment of this AVM. Typically, multiple clips are needed. In this case, four clips were deployed in a zipper-like fashion for successful hemostasis. Bleeding AVMs located on the dependent colon can be difficult to localize. Patient repositioning, or immersion of the AVM underwater, as demonstrated here, may be useful in this setting. Mechanical hemostasis with endoscopic clipping can then be accurately applied. Multiple AVMs were identified in the right colon of this elderly patient who presented with recurrent bleeding. The use of a bipolar cautery device has demonstrated that the patient's right colon is also affected by bleeding. The recommended published settings are 15 watts with 2- to 3-second pulses until obliteration. In this case, following initial cautery, notable bleeding is seen from the central feeding vessel. Simultaneous probe irrigation helps wash blood and clot to maintain a clear visualization. Thermal pulses are directly applied to the affected mucosa and are repeated until complete obliteration. Though uncommon, transmural injury has been reported using this technique. Endoscopic band ligation has become the mainstay of treatment for bleeding hemorrhoids that are refractory to medical therapy. It is an extension of the application of esophageal variceal band ligation. Redundant rectal mucosal tissue is suctioned into the banding device, and bands are released by pulling a wire at the tip of the endoscope. Care is taken not to treat the dentate line. If the patient experiences pain with the endoscopic suctioning, then suction should be released, as the squamous epithelium beneath the dentate line is likely involved. A different hemorrhoidal plexus is then targeted, and rectal mucosa is suctioned into the cap. Studies have demonstrated that deployment of up to three bands is safe and well-tolerated by patients. The technique is shown in detail in the endoscopic approach to hemorrhoids self-educational DVD. Similar to peptic ulcers, bleeding solitary rectal ulcers can be treated with mechanical or thermal means. APC was used to treat the visible vessel of the solitary rectal ulcer. Following treatment, medical therapy using bulking agents and stool softeners, and avoidance of straining and digital manipulation are needed. In some refractory cases, surgery is the only option. As post-polypectomy bleeding can be a challenge to treat, we advocate for its prevention. Prevention using injection of epinephrine, clipping, or looping is a key step in minimizing post-polypectomy bleeding. Post-polypectomy bleeding prevention is demonstrated here. Epinephrine is injected to the short stalk of this large, semi-pedunculated polyp prior to standard snare resection, in order to prevent immediate bleeding. The pale mucosa surrounding the base of the polyp following epinephrine injection can be appreciated. Snare resection is then performed. Following resection, endoscopic clipping was used to ligate the feeding vessel to prevent delayed bleeding. Three clips were placed, one at the vessel and two additional clips at opposite sides, in order to ligate the feeding vessel both proximally and distally. Following endoscopic submucosal dissection of a large rectal villus adenoma, a non-bleeding pulsatile vessel can be seen. Care is taken to precisely clip the exposed vessel to minimize post-resection bleeding. A large clot is seen adhered to the base of a prior polypectomy site. It is important to remove the clot in order to directly visualize the underlying vessel. A small snare is used to guillotine the clot, with care not to resect the potential vessel. The area is further washed. After exposure of the vessel, mechanical hemostasis can be accurately directed. A post-polypectomy bleed is treated in this case using endoscopic clipping. We stress good endoscope handling with fine application techniques. Keeping the clip in the target close to the endoscope allows controlled deployment of the clip. A tangential approach, along with minimal suction to collapse the lumen before deployment, permits maximal tissue capture surrounding the vessel. Although a single clip may be sufficient for adequate clamping of a protruding vessel, we typically place two additional clips in order to ligate the feeding vessel. These steps are shown in detail in the endoscopic clipping technique self-educational DVD. A post-polypectomy bleed is treated in this case using endoscopic looping. Successful endoscopic looping application requires practice to gain familiarity with the device. Application is similar to a standard polypectomy snare. The operator must be careful to apply enough tension when closing the loop to ligate the feeding vessel without transecting the stalk. Viewers are referred to the endoscopic looping technique self-educational DVD for further detailed instruction. Rectal dolophoid bleeding is rare. We typically use similar treatment as in gastric dolophoid bleeding with mechanical hemostasis. Our strategy is to use epinephrine while the band is being loaded in order to provide temporary hemostasis prior to band ligation therapy. 1 cc of epinephrine is injected submucosally into the quadrant surrounding the artery. The protuberant vessel is targeted and suctioned into the cap for band deployment. Argon plasma coagulation is commonly used for the treatment of moderate to severe radiation proctopathy. In the rectum, the setting is 1.2 liters per minute and a power of 60 watts. The catheter is positioned close to the endoscope, and the argon is sprayed close to the mucosal surface at the targeted areas. Multiple treatment sessions are required. In cases of anal canal involvement manifesting as severe pain, zinc oxide ointment can also be applied. The next case of radiation proctitis showed improved symptomatology following serial APC treatment sessions. The classic endoscopic findings of angioectatic vessels are seen under pools of fresh blood. Argon is fired through a forward viewing probe in a non-contact fashion to coagulate the lesions. It is necessary to clean the tip of the probe during the intervention to remove cauterized debris. The procedure is continued until all visible lesions are ablated. At six weeks, the patient reported an 80% reduction in bleeding episodes. Endoscopy showed improved mucosal appearance with healing ulcers at the site of the prior APC treatments and scattered telangiectasias that underwent further treatment. Nine weeks later, the patient reported almost resolution of his symptoms. Only a few lesions were visible on endoscopic examination. At this point, further treatment would be dictated by the patient's symptoms. The role of capsule endoscopy and double balloon endoscopy in acute severe lower gastrointestinal bleeding is to be determined. There are times when lower gastrointestinal bleeding is not amenable to endoscopic therapy, as in this case of severe large arterial diverticular bleeding refractory to endoscopic clipping. We emphasize a multidisciplinary team approach with close collaboration between the gastroenterologist, radiologist, surgeon, and internist in the approach to acute severe lower GI bleeding. Urgent endoscopy can be safe and efficacious in the treatment of lower gastrointestinal bleeding. More prospective studies are needed in the endoscopic management of acute severe lower gastrointestinal bleeding. With an enthusiastic team, proper patient resuscitation and preparation, thoughtful endoscope and equipment selection, and proficiency in techniques, we anticipate a promising endoscopic role.

lower gastrointestinal bleeding

angiography

endoscopic therapy

colonoscopy

diagnostic approaches

patient stratification

prospective studies