1.1

Esophageal strictures

• •
  

  Esophagogastroduodenoscopy (EGD) should be the initial diagnostic test in patients who (1) present with dysphagia consistent with an esophageal obstruction; (2) are at least 40 years of age with new onset dysphagia, and (3) in any patient with dysphagia and alarm symptoms (e.g. odynophagia, weight loss, anemia, etc).

  
  
• •
  

  Box 1 depicts the etiologies of mechanical esophageal obstruction.

  
  
  
  

  Box 1

  
  

  Causes of esophageal strictures

  
  

  
  

  
  

  
  
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    Peptic injury.

    
    
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    Schatzki’s ring.

    
    
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    Esophageal webs.

    
    
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    Esophageal cancer.

    
    
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    Corrosive injury.

    
    
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    Radiation therapy.

    
    
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    Esophageal surgery.

    
    
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    Eosinophilic esophagitis.

    
    
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    Sclerotherapy.

    
    
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    Photodynamic therapy (PDT).

    
    
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    Endoscopic mucosal resection (EMR).

    
    
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    Radiofrequency ablation (RFA).

    
    
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    Cryotherapy.

    
    
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    Sclerotherapy.

    
    
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    Infectious esophagitis.

    
    
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    Pill-induced esophagitis.

  
  

  
  
  
  
• •
  

  Anticoagulants should be discontinued for the procedure, based on existing recommendations (see Ch. 1 ).

  
  
• •
  

  The risk of bacteremia after esophageal bougienage is 12–22%, which is less than that associated with brushing of teeth. Antibiotic prophylaxis solely to prevent infectious endocarditis is not recommended prior to luminal stricture dilation.

  
  
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  Patients should fast for at least 4 h prior to the procedure, and ideally 8 h for patients who have eaten food. In certain clinical scenarios, such as achalasia dilation, patients should fast for longer time periods (see below).

  
  
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  Strictures are anatomically classified into simple or complex strictures. Complex strictures have at least one of the following features: asymmetry, diameter ≤12 mm, or inability to pass the endoscope. Complex strictures that are long or too tight to allow passage of an endoscope can be safely dilated under fluoroscopic guidance.

  
  
• •
  

  The esophageal mucosa should be examined for endoscopic features of eosinophilic esophagitis (EE). Esophageal dilation in the setting of EE carries a high risk for deep tears and esophageal perforation. Dysphagia in the setting of EE responds well to topical steroid therapy, and dilation may not be necessary.

  
  
• •
  

  For patients who complain of dysphagia, but do not have an endoscopically visible stricture, empiric esophageal dilation is discouraged. This technique has not been shown to be clinically effective. In addition, the patients may have undiagnosed EE, and dilation in this clinical scenario carries an extremely high risk of complication.

Clinical Tips

• •
  

  Patients with achalasia may need a prolonged fast prior to dilation because of a higher risk of aspiration due to esophageal stasis.

  
  
• •
  

  Look for endoscopic features of eosinophilic esophagitis: ringed esophagus and mucosal furrows. If EE is suspected, a total of five biopsy specimens must be obtained from the proximal and distal esophagus.

  
  
• •
  

  Do not perform empiric dilation for esophageal dysphagia when a stricture is not identified: it is clinically ineffective and has the potential risk of serious complications.

  
  
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  Biopsy specimens of the stricture should be obtained to exclude malignancy when the clinical presentation (such as rapid progression of dysphagia or significant weight loss) or the endoscopic appearance (such as the presence of a mass) is suggestive.

  
  
• •
  

  Biopsy specimens of a stricture to rule out occult malignancy should be obtained in patients with strictures that are refractory to dilation.

1.2

Gastric, pyloric, and small bowel strictures

• •
  

  Non-esophageal upper GI (UGI) strictures occur most commonly at the pylorus and manifest as gastric outlet obstruction. Etiologies of gastric or pyloric strictures are illustrated in Box 2 . Peptic ulcer disease (PUD) is the most common cause of gastric outlet obstruction.

  
  
  
  

  Box 2

  
  

  Causes of non-esophageal upper GI strictures

  
  

  
  

  
  

  
  
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    Peptic ulcer disease.

    
    
  • •
    

    Corrosive injury.

    
    
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    Crohn’s disease.

    
    
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    Radiation therapy.

    
    
  • •
    

    Postoperative.

  
  

  
  
  
  
• •
  

  Endoscopic dilation of UGI strictures due to Crohn’s disease often do not respond long term due to the high recurrence rate.

  
  
• •
  

  The use of fluoroscopy is advocated for strictures that cannot be traversed with the scope.

  
  
• •
  

  Roux-en-Y gastrojejunal bypass (RYGB) is one of the most common surgeries performed today for the treatment of morbid obesity. Gastrojejunal stomas are generally 10–12 mm in diameter. Anastomotic strictures are defined as stomas with diameter <10 mm and occur in 3–28% of these patients.

Clinical Tips

• •
  

  History of non-steroidal anti-inflammatory drugs (NSAIDs) intake needs to be elucidated in these patients and Helicobacter pylori infection needs to be ruled out.

  
  
• •
  

  Prolonged gastric outlet obstruction may result in gastric atony. Response to endoscopic therapy is not immediate in these patients.

  
  
• •
  

  Suspicious strictures must be biopsied to rule out malignancy.

1.3

Ileocolonic and colonic strictures

• •
  

  Etiologies of ileocolonic and colonic strictures are depicted in Box 3 . The most common site for these strictures is at surgical anastomoses.

  
  
  
  

  Box 3

  
  

  Causes of ileocolonic and colonic strictures

  
  

  
  

  
  

  
  
  • •
    

    Postoperative.

    
    
  • •
    

    Crohn’s disease.

    
    
  • •
    

    Radiation injury.

    
    
  • •
    

    NSAID colopathy.

    
    
  • •
    

    Diverticular disease.

    
    
  • •
    

    Ischemia.

    
    
  • •
    

    Malignancy.

  
  

  
  
  
  
• •
  

  Dilation of colonic strictures should only be performed if the patient is symptomatic.

  
  
• •
  

  NSAID colopathy most commonly manifest in the right colon and may lead to colonic strictures with a pathgnomonic ‘diaphragm type’ appearance.

3.1

General principles

3.1.1

Dilation using bougies

• •
  

  Bougies exert both shearing and radial force and dilate progressively from the proximal to the distal end of the stricture ( Fig. 1 ).

  
  

  
  

  
  

  

  
  

  
  

  Radial and longitudinal forces. Bougies are associated with longitudinal dilation forces (A), while balloon dilation is associated with radial dilation forces (B).

  
  
  
  
• •
  

  The initial dilator size chosen should equal the estimated diameter of the stricture.

  
  
• •
  

  Apply the ‘rule of 3’: Use no more than three dilators successively larger than the first dilator to meet moderate resistance when passed. This rule is a general guideline, and physicians should use their clinical discretion when dilating strictures.

  
  
• •
  

  Savary dilation involves passage of spring-tipped guidewire via the working channel of the endoscope, followed by withdrawal of the endoscope while leaving the guidewire in place ( Fig. 2 ).

  
  

  
  

  
  

  

  
  

  
  

  Bougies.

  
  
  
  
• •
  

  If the stricture is not traversable by the endoscope, then the guidewire is passed through the stricture under fluoroscopic guidance, with the tip of the endoscope placed just above the stricture. The endoscope is then withdrawn leaving the guidewire in place. One should not advance the guidewire if firm resistance is met.

  
  
• •
  

  A conservative approach to dilation is recommended to reduce the risk of perforation. Patients are usually brought back in 1–2 weeks for repeat sessions to achieve sufficient dilation.

Clinical Tips

• •
  

  Do not try to accomplish too much dilating in one setting.

  
  
• •
  

  Apply the ‘rule of 3’ as a guideline when using bougie dilation. Use no more than three dilators successively larger than the first dilator to meet moderate resistance when passed.

3.1.2

Dilation using balloons

• •
  

  Balloons exert radial force only and the force is applied simultaneously to the entire length of the stricture ( Fig. 1 ).

  
  
• •
  

  The ‘rule of 3’ does not apply to balloon dilators.

  
  
• •
  

  There are multiple TTS balloons that are available in either single or multiple diameters. The balloons may be passed with or without wire guidance ( Fig. 3 ).

  
  

  
  

  
  

  

  
  

  
  

  Ballon dilation. Balloons can also be placed on a guidewire outside the endoscope (A). Through the scope (TTS) esophageal balloonscan be non-wire guided (B) or wire guided (C).

  
  
  
  
• •
  

  The balloon is advanced through the working channel of an endoscope and then through the stricture under direct endoscopic visualization ( Figs 4, 5 ).

  
  

  
  

  
  

  

  
  

  
  

  Balloon dilation. Syringe gun, manometer and balloon (A).Through the scope (TTS) balloon (B), and following inflation (C). TTS balloon is inserted into the operating channel (D).

  
  

  
  

  
  

  

  
  

  
  

  Dilation of an esophageal stricture with a balloon. (A) Peptic stricture. (B) The balloon is placed across the stricture – note the ‘waist’ (arrow). (C) Note the obliteration of the waist following successful dilation. (D) Endoscopic image of the stricture during balloon dilation. (E) Following dilation: note the presence of several mucosal tears (white arrows).

  
  
  
  
• •
  

  The balloon should remain inflated for 30–60 s although the optimal duration is not known.

  
  
• •
  

  Fluoroscopic and wire guidance may be used for tight strictures that are not traversable with the endoscope.

  
  
• •
  

  Most widely used balloons are the controlled radial expansion (CRE) TTS balloons, which have three different inflation steps that achieve graded dilation.

Clinical Tips

• •
  

  It is of the utmost importance to maintain balloon position through the stricture during balloon inflation. The proximal portion of the catheter remaining outside of the endoscope should be held firmly against the endoscope using the endoscopist’s left little finger in order to prevent the balloon from slipping out of the stricture as it is inflated. Failure to do so may cause the balloon to slip out of the stricture and only part of the stricture may be dilated. In general, a slow inflation of the balloon to anchor to its initial diameter will secure it in the stricture and minimize the risk of migration. In addition, use of the longer balloon will help to minimize slipping out of the stricture.

  
  
• •
  

  You cannot apply the ‘rule of 3’ to balloon dilation.

  
  
• •
  

  Inflate the balloon using water and with radiologic product of contrast rather than air, because liquid is less compressible than gas in tight strictures.

3.2

Esophageal strictures

• •
  

  No difference in outcome has been observed between bougie and balloon dilation.

  
  
• •
  

  Schatzki’s rings are best treated with passage of single large diameter bougie (16–20 mm) to achieve rupture of the ring. Although most patients experience symptom relief after dilation, dysphagia recurs in 90% of patients within 3 years. Repeat dilation is advised on a needed basis. There is some evidence that acid suppression may prevent recurrence of Schatzki’s rings.

  
  
• •
  

  Webs occur in the upper and mid-esophagus and respond well to bougie dilation.

  
  
  
  

  Warning!

  
  

  
  

  Do not mistake eosinophilic esophagitis for multiple esophageal webs. These are different pathologies. Eosinophilic esophagitis carries a high risk of perforation, especially if dilation is performed with a single large diameter bougie.

  
  
  
  
• •
  

  Peptic strictures may be treated with bougienage (using the ‘rule of 3’) or balloon dilation. Patients should be placed on proton pump inhibitor (PPI) therapy and strictures will recur in as few as 30% of these patients.

  
  
• •
  

  Corrosive strictures require more dilation sessions and are associated with a higher recurrence rate as compared to peptic strictures. The use of bougies seems most suitable for these strictures.

  
  
• •
  

  Anastomotic strictures are common after esophagectomy, and are most commonly treated with balloon dilation.

  
  
• •
  

  Radiation-induced strictures are best treated with bougie dilation.

  
  
• •
  

  Injection of steroids into benign recurrent or refractory esophageal strictures may improve the outcome of dilation.

  
  
  
  

  Clinical Tips

  
  

  
  

  Steroid injection technique

  
  

  The procedure involves using 200 mg of triamcinolone (40 mg/mL). Using a standard sclerotherapy catheter, 1 mL aliquots are injected into the distal margin of the stricture in a four-quadrant fashion.

  
  
  
  
• •
  

  Dilation of malignant strictures provides only temporary relief of dysphagia that lasts from a few days to 2 weeks and it may be performed using either bougie or balloon dilation. Dilation is usually performed to allow passage of echoendoscope to perform tumor staging, stent placement, or laser therapy.

  
  
• •
  

  ASGE guidelines for the performance of esophageal dilation are summarized in Box 4 .

Clinical Tips

• •
  

  If you are not sure if the stricture is peptic or a Schatzki’s ring, treat it as a peptic stricture by using the ‘rule of 3’.

  
  
• •
  

  Remember that you only need to dilate the stricture to 13–15 mm diameter to relieve dysphagia.

  
  
• •
  

  PPI therapy improves outcome of peptic stricture dilation. This may also apply to Schatzki’s rings.

3.3

Achalasia

• •
  

  A thorough EGD examination is performed first to clear the esophagus of luminal contents, exclude esophageal or proximal gastric cancer (causing secondary achalasia), determine the extent of esophageal tortuosity, and identify the presence and localization of a hiatal hernia for appropriate localization of the LES fluoroscopically.

  
  
• •
  

  Pneumatic dilation is performed using Rigiflex balloon dilators with balloon diameters of 30 mm, 35 mm, or 40 mm.

  
  
• •
  

  Dilation is generally performed over a guidewire under fluoroscopic guidance initially using a 30 mm balloon. Non-fluoroscopically guided dilation using endoscopic visualization alone is feasible and can be performed safely in expert hands.

  
  
• •
  

  The balloon is first inflated to 3 pounds per square inch (PSI) to confirm appropriate localization of the balloon and looking for a waist in its center. The balloon is then inflated slowly up to a limit of 10 PSI. Complete obliteration of the waist should be noted fluoroscopically.

  
  
• •
  

  A water-soluble contrast esophagram should be obtained after the patient has awakened to rule out procedural perforation.

  
  
• •
  

  Fluoroscopy before and after dilatation should be performed to check for the presence of air in the mediastinum. If this is present it suggests that a perforation has occurred.

  
  
• •
  

  If the initial treatment is unsuccessful, repeat dilation with a larger balloon may be performed at a later setting.

  
  
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  Patients usually require 2–3 dilations over a 5-year period to remain in symptomatic remission.

  
  
• •
  

  Gastroesophageal reflux disease develops in some patients after pneumatic dilation, but it responds readily to PPI therapy.

  
  
• •
  

  ASGE guidelines for the performance of pneumatic dilation in achalasia are summarized in Box 5 .

Clinical Tips

• •
  

  Do not exceed a balloon pressure of 10 PSI because of an increased chance of perforation above this limit.

  
  
• •
  

  Do not perform pneumatic dilation in achalasia patients who are not fit for surgery because if perforation occurs, it may require surgical management. Alternative therapeutic options, such as Botox injection, may be better choices (see below).

3.4

Gastric/pyloric strictures

• •
  

  Pyloric strictures are mostly treated with balloon dilation although successful treatment using Savary dilators has also been reported in the literature.

  
  
• •
  

  A non-surgical approach for the treatment of these strictures is associated with high failure or recurrence rate. Repeat dilations every 1–2 weeks may be required to try to avoid surgery.

  
  
• •
  

  Long fibrous Crohn’s strictures are best treated surgically.

  
  
• •
  

  Pyloric strictures that are not traversable and those that are long and extend to the C loop of the duodenum are best dilated by passing the balloon over a guidewire under fluoroscopic guidance.

  
  
• •
  

  Gastrojejunal anastomotic strictures in RYGB patients can be treated effectively by using either balloon or bougie dilators. Dilation to 15 mm only is recommended to avoid weight regain.

3.5

Small intestinal/colonic strictures

• •
  

  Use an upper endoscope for high-grade left-sided strictures and a pediatric colonoscope for more proximal strictures. Enteroscopy (push or balloon) can be used to access and dilate strictures beyond the reach of an upper endoscope or colonoscope.

  
  
• •
  

  These strictures are usually treated using balloon dilators. Bougie dilation may be suitable for distal colonic or rectal strictures.

  
  
• •
  

  There is data to suggest that dilating colonic strictures to a diameter larger than 51 French is associated with better outcome. Large diameter balloons (up to 25 mm in size) are available for the treatment of colonic anastomotic strictures.

  
  
  
  

  Clinical Tip

  
  

  
  

  Most Crohn’s strictures occur at previous surgical anastomoses, although de novo stricture may occur and are also amenable to balloon dilation. However, only symptomatic strictures need to be treated!

  
  
  
  
• •
  

  Once the stricture is dilated allowing passage of the endoscope, the remaining proximal colon should be examined to evaluate for more proximal strictures. If there is any concern for malignancy, the stricture should be biopsied.

  
  
• •
  

  Colocolonic anastomotic strictures can be dilated to 15–18 mm in one treatment setting. In the setting of ileal or neo-terminal strictures, the initial dilation is taken to 10–12 mm. If there is no symptomatic response, a second dilation to 15 mm is undertaken during a later session. Strictures stemming from Crohn’s disease, diverticulitis, ischemia, or radiation therapy are rarely taken past 10–12 mm during the first treatment session.

Clinical Tip

If the colonic stricture cannot be traversed with an endoscope, fluoroscopy is used. Placement of the balloon over a guidewire is helpful for high-grade strictures and those associated with an end-to-side anastomosis. If difficulty is encountered in passing the guidewire across the stricture, a more flexible hydrophilic 0.021 or 0.035 mm ERCP guidewire may be helpful. In the case of near total colonic obstruction, a standard ERCP catheter may be placed over the guidewire and standard contrast will be used to determine the length and geometry of the stricture.

1.1

Gastric volvulus

Gastric volvulus is a rare, potentially life-threatening entity that occurs when the stomach twists upon itself ( Fig. 1 ). By definition, gastric volvulus is rotation of the entire or part of the stomach more than 180°. It is supra-diaphragmatic and associated with a paraesophageal or a mixed diaphragmatic hernia in two-thirds of the cases, and is subdiaphragmatic in the remaining one third. The volvulus is organoaxial in 60% of cases where the axis passes through the gastroesophageal and gastropyloric junctions, and mesenteroaxial in 40% of cases where the axis bisects the lesser and greater curvatures.

Barium contrast study showing organoaxial gastric volvulus (arrow).

Gastric volvulus can present as: (1) transient event with mild short-lived upper abdominal symptoms; (2) chronic volvulus with mild and non-specific symptoms such as dysphagia, hiccups, early satiety, bloating, heartburn, and upper abdominal discomfort, with symptoms being worse after meals; or (3) acute gastric volvulus which presents with sudden onset of severe pain in the upper abdomen or lower chest and unproductive retching. Some patients present with Borchardt’s triad of pain, unproductive retching, and the inability to pass a nasogastric tube.

Although strangulation is more common in organoaxial volvulus, it only occurs in 5–28% of these cases due to the rich blood supply of the stomach. Mesenteroaxial volvulus usually causes incomplete obstruction that may be intermittent in nature.

If gastric volvulus is associated with a diaphragmatic hernia, physical examination may reveal evidence of the stomach in the left chest. Chest X-ray will reveal a gas-filled viscus in the chest. The diagnosis is usually confirmed with a barium upper gastrointestinal study. Upper endoscopy will show twisting of gastric folds at the point of torsion.

Warning!

• •
  

  EGD should be avoided if there is suspicion of gastric ischemia or perforation, such as in patients with rebound abdominal tenderness.

  
  
• •
  

  If EGD is performed, the endoscope should be advanced forward gently and air insufflation should be kept to a minimum.

Acute gastric volvulus carries a high mortality risk if not recognized early. Early diagnosis and surgical correction remain the mainstays of therapy. Nonetheless, gastroenterologists still play a crucial role in the diagnosis and management of acute and chronic gastric volvulus.

• •
  

  Chronic gastric volvulus presents with mild and non-specific symptoms. The endoscopist performing the EGD can recognize the presence of twisted gastric folds, which establishes the diagnosis.

  
  
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  An endoscopist may diagnose acute gastric volvulus when performing upper endoscopy on a patient with more severe and acute symptoms. Stomach decompression with a nasogastric tube may be attempted. Reduction of an acute volvulus may be achieved with this intervention alone.

  
  
  
  

  Clinical Tip

  
  

  
  

  Placement of a nasogastric tube in acute gastric volvulus may be unsuccessful in patients with organoaxial rotation due to complete obstruction at the cardia.

  
  
  
  
• •
  

  The gastric mucosa should be inspected carefully for signs of ischemia and necrosis. The examination should be aborted if these signs are present because such patients are at higher risk of perforation with air insufflation.

  
  
• •
  

  If signs of gastric infarction are not present, acute endoscopic reduction of the volvulus may be considered using the alpha-loop maneuver, which should be performed under fluoroscopic guidance.

  
  
  
  

  Clinical Tips

  
  

  
  

  The alpha-loop maneuver ( Fig. 2 )

  
  

  
  

  
  
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    The endoscope is slowly advanced through the narrow lumen formed by the twisted gastric folds of the fundus or body into the antrum. Once the antrum is entered, a J-turn maneuver is performed to confirm the passage of the endoscope through the gastric volvulus.

    
    
  • •
    

    The endoscope is then withdrawn back into the fundus. The endoscope is retroflexed and advanced with gentle pressure in the proximal stomach to form an alpha-loop. The tip of the endoscope is passed anterior to the retroflexed portion and re-advanced through the narrowed lumen into the antrum.

    
    
  • •
    

    The endoscope is then torqued in a clockwise manner to allow untwisting of the alpha-loop and reduction of the gastric volvulus.

  
  

  
  

  
  

  

  
  

  
  

  Alpha-loop maneuver. (A) An Olympus magnetic imager showing an alpha loop and (B,C) the reduction of the volvulus, with straightening of the colonoscope.

  
  

  
  
  
  
• •
  

  In surgically fit patients, semi-elective laparoscopic gastropexy should follow the reduction of gastric torsion after the patient is stabilized. Associated diaphragmatic hernias should also be repaired.

  
  
• •
  

  In surgically unfit patients, simple endoscopic gastropexy may be performed by placement of one or two percutaneous gastrostomy (PEG) tubes.

  
  
• •
  

  A management algorithm for patients with gastric volvulus is illustrated in Figure 3 .

  
  

  
  

  
  

  

  
  

  
  

  Management algorithm for patients with acute gastric volvulus.

  
  

1.2

Colonic volvulus

Colonic volvulus is the third most frequent cause of large bowel obstruction after neoplasms and diverticulitis. Whereas colonic neoplasms and diverticulitis usually result in an open-loop obstruction where the lumen is occluded at a single point along the bowel segment, colonic volvulus occurs when a colonic segment becomes twisted on its mesenteric axis and occludes both ends of the bowel segment resulting in a closed-loop obstruction ( Fig. 4 ). The mesentery gets trapped and the blood supply to the bowel segment becomes strangulated, potentially leading to gut ischemia, necrosis and perforation. Delay in diagnosis and decompression compromises viability of the bowel and is a major cause of mortality.

(A) Plain AXR showing grossly distended loop of sigmoid colon. (B) Contrast radiology shows typical ‘bird’s beak’ occlusion at site of volvulus (arrow).

The sigmoid colon ( Fig. 4 ) and cecum ( Fig. 5 ) are the most frequent sites of colonic volvulus, accounting for 75% and 22% of all cases, respectively. Patients with acute colonic volvulus present most commonly with acute abdominal distension and may have other non-specific symptoms of abdominal pain, nausea, vomiting, and constipation. The diagnosis of colonic volvulus can be made with plain abdominal films (supine and upright) or water-soluble contrast enemas in 85% of the cases.

Clinical Tips

• •
  

  The use of barium as the contrast medium during contrast enema studies in patients with suspected colonic volvulus is discouraged because of risk of severe peritonitis in case of bowel perforation.

  
  
• •
  

  A contrast-enema study may occasionally cause volvulus detorsion.

Cecal volvulus. (A) Contrast enema study showing a cecal volvulus. (B) Reduction of the cecal volvulus with rectal tube inserted.

Acute colonic volvulus should be managed on an emergent basis. Patients with colonic necrosis/perforation should be managed surgically. A more conservative approach with an initial attempt at endoscopic detorsion and decompression can be followed in more stable patients ( Fig. 6 ). The benefits of such a strategy are:

• •
  

  Avoid emergency surgery on an un-prepped colon with risk of field contamination

  
  
• •
  

  Avoid colostomy and its associated morbidity and mortality

  
  
• •
  

  Improve quality of life by avoiding colostomy

  
  
• •
  

  Allow a one stage semi-elective surgery with the possibility of a laparoscopic approach

  
  
• •
  

  Assess the viability of colonic mucosa.

Clinical Tips

Endoscopic treatment of colonic volvulus

• •
  

  Consult with your surgical colleagues before any attempt at endoscopic management of colonic volvulus.

  
  
• •
  

  Avoid excessive air insufflation to minimize risk of perforation.

  
  
• •
  

  Consider using carbon dioxide, if available, for colonic insufflation.

  
  
• •
  

  Examination should be aborted if there is any evidence of colonic gangrene (e.g. the presence of bloody effluent in the colonic lumen is an indication of bowel gangrene); detorsion should be avoided in these cases as it can precipitate an irreversible septic shock.

  
  
• •
  

  The volvulus should be traversed slowly with a flexible endoscope in the usual manner. A gush of stool is expected after successful detorsion.

  
  
• •
  

  Place a decompression tube over a guidewire to decompress the distended colon and to decrease the early recurrence risk. Early recurrence rate is unacceptably high without tube placement. The tube should be placed on low intermittent suction and should be flushed with 20–30 mL of water or normal saline solution every 6 hours to maintain patency.

  
  
• •
  

  Perform supine and upright abdominal radiography to confirm successful detorsion and to exclude pneumoperitoneum.

  
  
• •
  

  Endoscopic treatment of colonic volvulus is only a temporizing measure.

Warning!

Endoscopic management of cecal volvulus is less well defined than sigmoid volvulus because of a lower success rate (<33%) and a heightened cecal perforation rate because of the thinned-wall cecum.

Endoscopic view of a sigmoid volvulus. (A) Before reduction. (B) Following endoscopic reduction.

Colonic segmental resection and primary anastomosis is considered the treatment modality of choice of colonic volvulus after successful endoscopic detorsion. Non-resectional techniques such as colonopexy and colonostomy carry a substantial risk of recurrence, but may be considered in high-risk patients.

2.1

General concepts

• •
  

  Of patients with esophageal cancer, 50–60% present with surgically unresectable disease

  
  
• •
  

  Dysphagia is the most distressing symptom

  
  
• •
  

  Dilation only transiently improves dysphagia and carries a significant risk of perforation

  
  
• •
  

  Dilation is primarily used as an adjunct treatment for stenting

  
  
• •
  

  Stenting provides rapid relief of dysphagia

  
  
• •
  

  All esophageal SEMS are covered

  
  
• •
  

  The three most commonly studied SEMS are: Ultraflex, Wallstent, and Z-stent. Other stents exist

  
  
• •
  

  The Polyflex stent is FDA-approved for the palliation of malignant diseases and for the treatment of benign diseases of the esophagus

  
  
• •
  

  Currently available esophageal stents are not placed through the scope.

2.2

FDA-approved expandable esophageal stents ( Table 1 )

2.2.1

Ultraflex stent

• •
  

  Ultraflex stent is partially coated (with a polyurethane membrane lining the middle of the stent while the proximal and distal 1.5 cm is uncovered).

  
  
• •
  

  It has an easy-to-use delivery system which is 5.3 mm in diameter and can be deployed from the proximal to the distal end or vice-versa.

  
  
• •
  

  The flared proximal end reduces the risk of food pocket formation between the stent and the wall and anchors the stent to the esophageal wall.

  
  
• •
  

  The stent can theoretically be repositioned, if necessary, by means of a wire at its upper end.

  
  
• •
  

  It is slow to expand (encouraging the patient to start eating again cautiously and gradually).

  
  
• •
  

  Expansion is occasionally incomplete, requiring balloon dilation, which is not always effective. Perforation is rare.

  
  
• •
  

  The Ultraflex stent has no bare metal edges and is less traumatic to the mucosa compared to the Wallstent.

Clinical Tips

Among all SEMS, the Ultraflex stent produces the least radial expansive force which, in theory, may be clinically relevant:

• •
  

  Decreased risk of fistula formation

  
  
• •
  

  Decreased risk of perforation

  
  
• •
  

  Diminished efficacy (less relief from dysphagia).

Table 1

FDA-approved expandable esophageal stents

Stent type	Manufacturer	Material	Covering	Deployment diameter (mm)	Release system	Degree of shortening	Features
Ultraflex	Boston Scientific	Nitinol	Partial or uncovered	18, 22	Proximal or distal	30–40%	Proximal flared end, no bare metal ends
Wallstent II	Boston Scientific	Cobalt-based alloy	Partial	20	Distal	20–30%	Flared ends, bare metal ends, reconstrainable
Z-stent	Cook Endoscopy	Stainless steel	Full or partial	18	Distal	None	Flared ends
Z-stent with Dua Antireflux Valve	Cook Endoscopy	Stainless steel	Full	18	Distal	None	Windsock on distal end to prevent gastroesophageal reflux when placed across gastroesophageal junction
Alimaxx-E	Alveolus	Nitinol	Full (internally lined)	18, 22	Distal	None	Internally lined
Polyflex	Boston Scientific	Polyester/silicone	Full	16, 18, 21	Distal	30–40%	Proximal flared end, approved for removability

 

2.3

Technique of stent placement

• •
  

  The Ultraflex, Alimaxx-E, and Polyflex stents may be placed endoscopically without fluoroscopic guidance; however, fluoroscopic guidance is commonly used.

  
  
  
  

  Clinical Tips

  
  

  
  

  
  

  
  
  • •
    

    If a stricture is not traversable with a standard endoscope, a pediatric endoscope (6 mm diameter) may be used, if available.

    
    
  • •
    

    If the stricture is not traversable with the endoscope, stent placement must be performed under fluoroscopic guidance.

    
    
  • •
    

    The stricture needs to be dilated to allow passage of the delivery system (usually to a diameter of 9–10 mm and not exceeding 12–14 mm).

    
    
  • •
    

    If an endoscope cannot be passed beyond the stricture, the length and geometry of the stricture can be defined using a balloon and water insoluble contrast.

  
  

  
  
  
  
• •
  

  The proximal and distal borders of the tumor are marked by endoscopic clips, injection of contrast material using sclerotherapy needle, or placement of external radio-opaque markers ( Fig. 3 ).

  
  
  
  

  Clinical Tip

  
  

  
  

  It is best to have the patient in supine position when external markers are placed, for optimal fluoroscopic visualization. Keep patient in same position during stent deployment.

  
  

  
  

  
  

  

  
  

  
  

  

  
  

  
  

  Insertion of esophageal stent. (A) Placement of radio-opaque marker and guide wire. (B) Measure distance of proximal and distal tumor margins from the teeth. (C) Delivery system through the stenosis. (D) Distal stent deployment. (E) The system is withdrawn. (F) Stent deployed.

  
  
  
  
• •
  

  A stiff guidewire is positioned in the stomach through the stenosis.

  
  
• •
  

  The scope is withdrawn.

  
  
• •
  

  The delivery system with the stent is passed to the stomach over a stiff guidewire. The system is then withdrawn and the stent deployed with the assistance of fluoroscopy, so that the markings on the stent indicate that placement will be with at least a 2 cm margin proximal and distal to the marked tumor margins.

  
  
• •
  

  Repeat endoscopic examination may be done to confirm the proximal end of the stent is above the proximal tumor margin.

  
  
  
  

  Clinical Tips

  
  

  
  

  
  

  
  
  • •
    

    Avoid traversing the stent after deploying it because of migration risk, as the stent has not fully expanded. Full stent expansion takes about 48 h.

    
    
  • •
    

    It is crucial to choose the proper stent length that will bridge the entire tumor. This may be accomplished by measuring the tumor length endoscopically or fluoroscopically.

    
    
  • •
    

    Remember that the chosen stent should be 2–4 cm longer than the stricture to allow for a 1–2 cm margin above and below the stricture proximal and distal margins. This allows for the covered portion of the stent to cover the stricture, thus reducing tumor ingrowth.

  
  

  
  
  
  
• •
  

  More than one stent may be needed to cover long strictures. The second stent is placed in the same manner and positioned such that the two stents overlap for a distance of about 1–2 cm.

  
  
  
  

  Clinical Tip

  
  

  
  

  Do not leave an excessive length of stent in the stomach because of the risk of gastric ulceration and bleeding when the stent rubs against the opposite gastric wall.

  
  
  
  
• •
  

  If deployment is suboptimal based on fluoroscopic appearance, the stent may be dilated using a TTS balloon.

  
  
• •
  

  Prescribe pain medications and proton pump inhibitor therapy before patient is discharged. Patients should also be advised on specific nutritional guidelines ( Box 1 ).

2.4

Stent retrieval techniques

• •
  

  The most commonly used method for retrieving stents is to grasp the proximal end of the stent with forceps or endoscopic snares, and then to pull out the endoscope, stent, and forceps/snare as one unit. Injury to the gastric or esophageal mucosa may occur and an overtube or a retrieval hood can be used to minimize this.

  
  
• •
  

  The stent may be removed using a regular upper endoscope. Some endoscopists prefer using the double-channel therapeutic endoscope with two rat-tooth forceps or a rat-tooth forceps and a snare for stent removal.

2.5

Outcome data (efficacy)

• •
  

  Technical success rates for placement of esophageal SEMS is close to 100%. Placement of SEPS (Polyflex) is more cumbersome and the technical success rate is reportedly lower than that of SEMS (approximately 85%).

  
  
• •
  

  Rapid and prolonged improvement of dysphagia occurs in the majority of patients.

  
  
• •
  

  Polyflex has higher migration rates compared to SEMS, especially when placed across the GE junction.

  
  
• •
  

  Migration rates are higher with benign disease (30–70%) and efficacy is significantly lower. Some studies report long-term improvement in as few as 6% of patients.

  
  
• •
  

  Although the Alimaxx-E stent is not FDA-approved for removability, it is the only SEMS that has an indication for removability. It is currently being widely used to treat both malignant and benign diseases of the esophagus. The stent appears easier to remove if it has been in place for a shorter period of time (e.g. 4–6 weeks).

2.6

Complications

Early (or procedure-related) complications of esophageal stent placement occur in 10% of procedures and consist of chest pain, aspiration pneumonia, stent misplacement (can be minimized by choosing a stent 4 cm longer than the length of the stricture) and perforation. Late complications occur in 35–45% of patients and consist of gastrointestinal bleeding, development of ERF, stent migration, food bolus impaction, gastroesophageal reflux, and tumor overgrowth at either end of the stent. Stents placed across the gastroesophageal junction have higher complication rates when compared to stents placed in the mid-esophagus. In like manner, there is a statistically significant increased rate of life-threatening complications and associated increased mortality rate when placing stents in patients with a prior history of chemotherapy or radiotherapy. It appears that tissue integrity is compromised with administration of chemotherapy or radiation therapy, and this predisposes SEMS patients to a higher risk of life-threatening complications. Tumor ingrowth is a late complication that has been reduced with the advent of silicone or polyurethane covering, but unfortunately at the risk of increased stent migration (16% migration rate for covered SEMS vs 4% for uncovered SEMS). Treatment options for management of tumor ingrowth include laser therapy, injection therapy, electrocoagulation, photodynamic therapy, argon plasma coagulator, and placement of an overlapping second SEMS.

Clinical Tips

• •
  

  When placing a stent across the gastroesophageal junction, choose a large diameter stent to decrease migration risk.

  
  
• •
  

  An antireflux stent may be useful.

3.1

General concepts

• •
  

  Patients with gastric outlet obstruction were historically treated with gastrojejunostomy with or without choledochojejunostomy.

  
  
• •
  

  A recent systematic review of palliative stent placement versus open or laparoscopic gastrojejunostomy for the treatment of patients with malignant gastric outlet obstruction suggested that endoscopic treatment is the preferred modality in patients with short life expectancy (<6 months).

  
  
• •
  

  The two FDA-approved duodenal stents are uncovered and can be placed through the working channel of a therapeutic endoscope (need a working channel ≥3.8 mm).

  
  
• •
  

  It is frequently not possible to traverse the stricture with the endoscope since a therapeutic endoscope is usually warranted.

  
  
• •
  

  Duodenal stents are best placed under fluoroscopic guidance.

  
  
• •
  

  There is usually no need to aggressively dilate the stricture in order to minimize risk of perforation.

  
  
• •
  

  Duodenal stents are not used for benign disease.

  
  
• •
  

  Patients with malignant duodenal obstruction often have or are at risk for biliary obstruction. Consider placing a biliary SEMS prophylactically before placing a duodenal SEMS.

  
  
• •
  

  Duodenal strictures are dilated (18–22 mm) only if biliary drainage is to be performed, since access to the papilla requires the use of a large diameter therapeutic duodenoscope.

3.2

FDA-approved expandable duodenal stents

See Table 2 .

3.3

Technique of stent placement

• •
  

  The insertion procedure of a duodenal stent is similar to that of an esophageal stent ( Figs 4, 5 ).

  
  

  
  

  
  

  

  
  

  
  

  Insertion of duodenal stent.

  
  

  
  

  
  

  

  
  

  
  

  Duodenal stenting. Tumor ingrowth in a previously placed duodenal stent. A wire is placed across the stent under (A) endoscopic and (B) fluoroscopic guidance. A second, followed by a third stent is deployed (C). (D) The final radiographic image with three duodenal stents.

  
  

  (Courtesy of Dr Ian Penman.)

  
  
  
  
• •
  

  Patients with gastric outlet obstruction have high gastric residuals and suction of gastric contents should be performed if possible, to minimize aspiration risk and optimize visualization.

  
  
• •
  

  Patients should be in supine or prone position to optimize fluoroscopic visualization.

  
  
• •
  

  If a patient is deemed high risk for aspiration, consider endotracheal intubation prior to stent placement.

  
  
  
  

  Clinical Tips

  
  

  
  

  
  

  
  
  • •
    

    The status of the biliary tree should be assessed before gastroduodenal stent placement.

    
    
  • •
    

    Placement of SEMS across the papilla will render endoscopic biliary access difficult, if not impossible.

  
  

  
  
  
  
• •
  

  If the tumor is located in the proximal duodenum without involvement of the papilla, a stent that is long enough to cross the lesion should be chosen, but not excessively long which will prevent access to the papilla. Therefore, accurate assessment of the length and location of the malignant stricture is important.

  
  
• •
  

  The stricture may then be accessed with a standard biliary balloon catheter over a guidewire under fluoroscopic guidance. Injecting dye through the stricture may help delineate the length, geometry, and extension of the stricture.

  
  
• •
  

  The selected stent should be about 4 cm longer than the stricture.

  
  
• •
  

  Prior to discharge, patients should be advised to advance from liquids to solids as tolerated and to avoid leafy vegetables, which may result in stent occlusion.

Clinical Tips

• •
  

  An expandable metal biliary stent should be placed before the duodenal stent is placed if there is known or impending biliary obstruction.

  
  
• •
  

  To treat biliary obstruction after placement of a duodenal stent, a percutaneous transhepatic approach is usually required.

  
  
• •
  

  Stenting of both the duodenum and the bile duct is the non-surgical equivalent of a traditional double surgical bypass (gastrojejunostomy and choledochojejunostomy).

3.4

Outcome data (efficacy) and complications

One systematic review that included 606 patients summarized the published evidence of the effectiveness and safety of gastroduodenal stenting. Technical success and clinical success were achieved in 97% and 89% of patients, respectively. There was no procedure-related mortality and serious complications (bleeding and perforation) were observed in 1.2% of patients. In addition, migration and obstruction (primarily due to tumor ingrowth) occurred in 5% and 18% of patients, respectively.

Jejunal stents may also be placed. These can sometimes be placed with a pediatric colonoscope; however, augmented enteroscopy with double balloon, single balloon or spiral enteroscope ( Fig. 6 ) provide a stable platform for stent insertion.

Jejunal stent insertion using spiral enteroscopy. (A) Small-bowel obstruction with tumor. (B) Deployment of SEMS using Endo-Ease Discovery overtube. (C) Endoscopic image of deployed SEMS. (D) Radiographic image of deployed SEMS.

(Courtesy of Dr Anne Marie Lennon, from Lennon AM, Chandrasekhara V, Shin EJ, Okolo PI. Spiral-enteroscopy-assisted enteral stent placement for palliation of malignant small-bowel obstruction. Gastrointestinal Endoscopy 2010; 71(2): 422-425.)

4.1

General concepts

• •
  

  All four FDA-approved colonic stents are SEMS.

  
  
• •
  

  All colonic stents currently in use are uncovered because the use of covered stents in the colon is associated with an unacceptably high migration rate.

  
  
• •
  

  Two SEMS can be placed through the scope (TTS) and the other two are non-TTS.

  
  
• •
  

  Few data exist on the use of colonic stents for the treatment of benign diseases of the colon.

  
  
• •
  

  Main indications for colonic stenting are:

  
  
  
  
  • ▪
    

    Bridge to surgery in patients with colorectal cancer (CRC) who present with total or subtotal colonic obstruction.

    
    
  • ▪
    

    Palliation of inoperable malignant colorectal obstruction.

  
  
  
  

  Box 3

  
  

  Rationale for colorectal stenting as a bridge to surgery

  
  

  
  

  
  

  
  
  • •
    

    Of patients with CRC, 7–29% present with or develop colorectal obstruction.

    
    
  • •
    

    Field contamination hazard exists with emergency surgery.

    
    
  • •
    

    Patients are usually malnourished and have dilated colons, both of which increase the surgical risk.

    
    
  • •
    

    Avoid colostomy: colostomy management is cumbersome to some patients, it worsens QoL, and its closure has significant morbidity and mortality of 37% and 7%, respectively.

    
    
  • •
    

    Avoids multistep surgery.

    
    
  • •
    

    Possible laparoscopic approach.

    
    
  • •
    

    Preoperative colonoscopy to clear the colon of synchronous tumors and more proximal strictures.

  
  

  
  
  
  
• •
  

  Smaller diameter stents are appropriate for proximal colonic stenting because the stool is still liquefied and smaller diameter stents may carry a lower perforation risk. Larger diameter stents are more appropriate for distal colonic strictures to prevent solid stool impaction within the stent lumen

  
  
• •
  

  Enema preps suffice for patients with total colonic obstruction or distal colonic obstruction. All other patients require standard colonoscopy preparation.

4.2

FDA-approved expandable colonic stents

Table 3 .

4.3

Technique of stent placement ( Figs 7, 8 )

• •
  

  Placement of colonic stents is more technically demanding than esophageal and gastroduodenal stents. Endoscopic placement alone can be performed for traversable strictures. Because of the frequent complexity of colonic strictures, colonic angulations, and the presence of stool, the use of fluoroscopic guidance is advocated.

  
  
• •
  

  For endoscopic placement alone, a small calibre endoscope is used to traverse the stricture. The stricture can be carefully dilated to 12–14 mm if needed. The geometry and length of the stricture are then determined with the endoscope. Subsequently, the guidewire is placed through the stricture and the scope is withdrawn. Only non-TTS stents may be used since TTS stents do not fit into the therapeutic channel of a small calibre endoscope. The stent is then placed over the guidewire, the endoscope is positioned just distal to the lesion, and the stent is deployed under endoscopic guidance.

  
  
• •
  

  Combined endoscopic and fluoroscopic placement obviates passage of the endoscope across the stricture. A therapeutic channel endoscope and a TTS-stent may be used. A biliary balloon catheter is passed through the stricture over a stiff guidewire and water-soluble dye is injected to delineate the geometry and length of the stricture. The stent is then placed under endoscopic and fluoroscopic guidance as described previously.

  
  
• •
  

  The stent chosen should be 4 cm longer than the stricture.

Clinical Tips

• •
  

  If the stricture lies within or close to an angulation, then the ends of the stent may be oriented towards the colonic wall after deployment, preventing adequate passage of fecal material through the stent. If this occurrence is anticipated, then it may be preferable to use a longer stent than expected to ensure that the ends of the stent are directed towards the lumen.

  
  
• •
  

  TTS-stents should be used for right sided lesions.

Insertion of colonic stent.

Colonic stent insertion. (A) Malignant colonic obstruction (B) that was palliated with placement of a self-expandable metal stent.

4.4

Outcome data (efficacy) and complications

• •
  

  Table 4 summarizes pooled analysis from a 14-year data collection that included 1198 patients.

  
  
  
  

  Table 4

  
  

  Pooled analysis of technical and clinical success rates

  
  

  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

  	Group	Patients ( n )	Cumulative (%)
  Technical success	Overall	1198	93.2
  	Bridge to surgery	407	91.9
  	Palliative	791	93.3
  Clinical success	Overall	1198	88.6
  	Bridge to surgery	407	71.7
  	Palliative	791	91

   
  
  
  
  
• •
  

  SEMS may be used effectively to treat patients with malignant rectal obstruction within 5 cm from the anal verge (anal pain occurs in 62% of patients).

  
  
• •
  

  SEMS may be used effectively to treat patients with malignant proximal colonic obstruction (technical success 95%, clinical success 85%).

  
  
• •
  

  Colonic stents are generally less effective for palliation of colorectal obstruction due to extrinsic malignant obstruction.

Clinical Tips

• •
  

  SEMS may be used effectively to treat benign colorectal obstruction with relief of obstruction in 95% of cases.

  
  
• •
  

  Serious complications occur in about 40% of patients, most of which occur 7 or more days after stent placement.

  
  
• •
  

  If SEMS are used for benign colorectal disease, surgery should be planned soon after stent placement (bridging).

  
  
• •
  

  See Table 5 for colorectal stent complications.

  
  
  
  

  Table 5

  
  

  Preoperative and palliative colorectal stents complications ( n = 826)

  
  

  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

  Mortality	0.3%
  Morbidity	5–10%
  Perforation	3%
  Migration	9%
  Bleeding/pain/tenesmus	10%
  Re-obstruction	9% (tumor ingrowth/overgrowth 74%, fecal impaction 20%, migration 6%)

   
  
  

4.1

Radiation proctopathy

APC has been shown to be an effective treatment for gastrointestinal bleeding associated with radiation proctopathy in several case series studies ( Fig. 3 ).

• •
  

  Patients must have a full bowel preparation, even if only treating the rectum, as there is an increased risk of explosion in an unprepared colon.

  
  
• •
  

  Care should be taken to avoid treatment close to the dentate line.

  
  
• •
  

  Power settings of 40–60 W and gas flow rates of 1–1.5 L/min have been evaluated.

  
  
• •
  

  Treatments are repeated every 1–2 months, with between 1 and 3 sessions usually required.

Radiation proctopathy. (A) Rectum with active bleeding from radiation proctopathy. (B) Following APC.

Complications include post procedure pain, particularly when treatment is administered close to the dentate line. Rare complications which have been reported include transient urinary retention, rectovaginal fistula, and rectal strictures. There are currently no randomized prospective trials comparing APC with laser and medical therapies.

4.2

Vascular lesions

APC is an effective treatment for gastric antral vascular ectasia (GAVE) ( Fig. 4 ) and angiodysplasia ( Fig. 5 ), and prevents recurrent bleeding associated with these lesions.

Classic appearance of gastric antral vascular ectasia.

APC treatment of angiodysplasia. (A) Small angiodysplastic lesion before coagulation. (B) Following APC.

GAVE ( Fig. 4 ) is an uncommon cause for upper gastrointestinal blood loss associated with cirrhosis and other chronic diseases ( Box 1 ). Involvement of the antrum can be patchy or diffuse. Patients often present with iron deficiency anemia. Improvements in hemoglobin levels and a decrease in transfusion requirements are seen in most patients. However, recurrence can be seen in 30–40% of patients between 20 and 30 months after therapy, which often requires further APC treatment.

• •
  

  Power settings between 40 and 100 W have been used.

  
  
• •
  

  Treatments are repeated every 1–2 months, with between 2 and 3 sessions usually required.

Angiodysplasias ( Fig. 5 ) can be found throughout the gastrointestinal tract and are effectively treated with APC. Angiodysplasias can be found throughout the gastrointestinal tract and are effectively treated with APC.

• •
  

  The 300 cm probes will often be required to ablate angiodysplasias of the mid and distal small bowel during push enteroscopy.

  
  
• •
  

  Successful ablation of angiodysplasia(s) is indicated by the presence of a white coagulum after treatment.

  
  
• •
  

  APC treatment of diffuse angiodysplasias require moving a probe in an side-by-side and up-and-down arc which is commonly referred to as ‘painting’ the lesion with short, 1–2 s applications.

  
  
• •
  

  For cecal angiodysplasias, consider submucosal injection with saline and/or dilute epinephrine prior to treatment to reduce the risk of perforation.

  
  
• •
  

  APC therapy significantly improves hemoglobin values and is associated with lower rates of overt bleeding in about 85–90% of patients.

4.3

Treatment of remnant polypoid tissue after piecemeal resection of large colonic polyps

APC has been shown to be effective in devitalizing any remnant polypoid tissue at the rim and base of a piecemeal polypectomy site. Polyps which are large (>1.5 cm), flat, extended, and/or located behind a fold or an angulated area of the colon often require piecemeal resection techniques. Patients undergoing APC have been shown to have significantly fewer recurrences. Treatment should be focused along the rim of the polypectomy site but short applications at the base can also be used. However, there has only been one small randomized study demonstrating these results.

4.4

Other applications

APC has been used for palliative debulking of obstructive tumors of the esophagus ( Figs 6, 7 ), stomach, ampulla, and rectum ( Figs 8, 9 ). While symptomatic improvement is seen in >90% of patients, multiple treatment sessions are often required. While there have been few randomized studies, a large series of patients with obstructive esophageal and cardia tumors underwent APC with maintenance of luminal patency in 64% of patients until death.

APC for the palliative treatment of an esophageal tumor. Start at the most distal extent of the tumor and work proximally.

(A) Esophageal cancer pre-treatment. (B) APC treatment of the tumor. (C) Esophageal cancer following treatment.

Palliative treatment of a tumor in the sigmoid colon. Start at the most distal extent of the tumor to avoid coagulation in the wrong direction.

APC treatment for palliation of rectal cancer. (A) Rectal cancer pre treatment. (B) After the first session of APC. (C) Prior to commencing second session of APC. (D) Following second session. (E) Appearance during treatment. (F) Appearance after the session. (G) Appearance before the last session. (H) Last session of APC. (I) Scar with complete destruction. As a result of this example, YAG laser has been replaced with APC.

APC has also been studied as therapy for bleeding peptic ulcers but concerns center on its inability to seal a bleeding vessel and the risk of precipitating further bleeding, especially from arteries >1 mm. Another potential role for APC in the future may be for shortening or trimming metal stents which have become displaced over time to prevent perforation or bleeding.

1.1

Foreign body lodged in the respiratory tract

This should be suspected if the patient has difficulty breathing or has wheezing.

1.2

Foreign body in the upper gastrointestinal tract

The ingestion of a foreign body can cause retrosternal pain, odynophagia, dysphagia, hypersialorrhea and sometimes vomiting in the case of large, obstructive objects. Subcutaneous emphysema can occur with esophageal perforation, while peritonitis suggests small or large bowel perforation. Sharp objects, such as toothpicks, meat or fish bones, razors, lapel badges, dentures or needles, can cause bleeding or perforation.

A high degree of suspicion is required in children or mentally impaired adults as 20–38% of children are asymptomatic, while up to 40% of children or non-communicative adults have no history of foreign body ingestion.