Gastroenterological Endoscopy. Группа авторов

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      10.3.2 Therapeutic Upper Gastrointestinal Endoscopy

      Therapeutic upper GI endoscopy has dramatically increased over the last 10 years and is associated with a much higher rate (approximately 10 times) of adverse events than diagnostic procedures.¹⁵

      Stricture and Achalasia Dilation

      Dilation of esophageal strictures and achalasia pneumatic dilation are associated with specific complications including perforation, bleeding, and bronchial aspiration. Bronchial aspiration can be prevented by endotracheal intubation, which is recommended in patients with comorbidities, although it is also associated with specific adverse events.¹⁶ Perforation risk varies with indication and technique used. Up to 4% risk has been described for pneumatic dilation of achalasia.¹⁷ It can be reduced by starting with a balloon diameter of 30 mm and not dilating greater than 35 mm.¹⁷ With the advent of POEM, the use of pneumatic dilation is likely to decrease.¹⁸ The risk of perforation when dilating malignant and caustic strictures is twofold compared with benign (peptic) strictures.¹⁹ Complex strictures (defined as an asymmetry, < 12 mm in diameter, or endoscopically impassable) are also associated with increased rates of complications.¹⁹ Another established risk factor for perforation is the level of operator experience. The risk of perforation during dilation is four times higher for trainees who have performed fewer than 500 upper GI endoscopies.³ Most perforations occur at the first session of dilation.²⁰ Three separate studies failed to show that bougie dilators are safer than balloon dilators in patients with benign strictures.²¹

      Stent Insertion

      Self-expandable metal stent (SEMS) placement is a method for palliating malignant dysphagia and malignant tracheoesophageal fistula.^22,23 SEMS can also be used to close upper GI fistulas in benign conditions.^24,25 Unfortunately, complications are frequent (20–40%).²⁶ Thoracic or epigastric pain is common after SEMS placement but is usually transient. Acute perforation is rare unless prior dilation was required. The risk of late perforation and bleeding seems to be higher with larger stents, and particular caution should be taken when stenting the gastroesophageal junction where asymmetrical pressure against the esophageal wall may precipitate ulceration, perforation, and/or bleeding. The use of larger stents, however, does decrease the rate of other adverse events, such as stent migration and tumor ingrowth.²⁶ After placement of a stent across the gastroesophageal junction, proton pump inhibitor (PPI) use and postural precautions are mandatory. The efficacy of antireflux stents has not been established.²⁷

      Late complications of stenting also include relapsing stenosis due to tissue hyperplasia (in the uncovered parts of partially covered stents) and tumor overgrowth. If the stent is placed for a benign indication, tissue hyperplasia may be treated by temporary placement of a second fully covered stent inside the first one, which will pressure necrose the inflammatory tissue and allow stent removal.^24,25,26 Following SEMS removal, secondary fibrotic strictures at the proximal or distal ends may occur, and are usually easily managed with dilation.

      Polypectomy, Endoscopic Mucosal Resection, and Endoscopic Submucosal Dissection

      Polypectomy, endoscopic mucosal resection (EMR), and endoscopic submucosal dissection (ESD) are commonly associated with bleeding, although most bleeding is intraprocedural, controlled endoscopically, and is not clinically relevant. Perforation occurs in 3% of esophageal resections and in 1% of gastric resections.^28,29,30 Cicatricial strictures are a late complication that mainly occur after circumferential esophageal resection.³¹ Delayed bleeding after esophageal or gastric EMR/ESD is uncommon (< 5%).^28,30 To prevent delayed bleeding, some authors recommend coagulation of all visible submucosal vessels during the procedure for gastric resections, but this and second-look endoscopy are not routinely recommended.³² PPI therapy is usually prescribed after the procedure. Delayed bleeding occurs more frequently after duodenal mucosal resection compared with esophageal and gastric resection, with bleeding rates ranging from 4 to 33%. Some authors suggest closure of the mucosa after resection with placement of multiple clips.³³

      In the last two decades, ablative therapies (such as argon plasma coagulation, photodynamic therapy, and mainly radiofrequency ablation) have emerged for the treatment of premalignant or early superficial malignant lesions, and as palliative therapy for some advanced tumors. Photosensitivity is a specific complication associated with the use of photodynamic therapy, but can also result in the development of strictures, especially when applied in the esophagus.^34,35 Stricture formation as a late complication can occur after circumferential radiofrequency ablation for treatment of dysplastic Barrett’s esophagus.

      Hemostasis of Nonvariceal Bleeding

      Hemostasis of nonvariceal bleeding includes a combination of injection therapy and thermal or mechanical therapy. Although adrenaline injection (0.1 mg/mL) does not result in complications, injection of sclerosants (such as polidocanol, ethanolamine, or absolute alcohol) should be avoided as they do not control bleeding³⁶ and could lead to life-threatening tissue necrosis.³⁷ Coaptive СКАЧАТЬ