Читать книгу Successful Training in Gastrointestinal Endoscopy - Группа авторов - Страница 36

To begin any gastrointestinal procedure, the endoscope must first be inserted into the lumen of the GI tract. Introduction of the endoscope requires a clear understanding of the relevant regional anatomy.

For upper GI endoscopy, this involves direction of the endoscope down the oropharynx into the esophagus. To avoid gagging, retching, and possible laryngospasm, the oropharynx should be appropriately anesthetized with a local anesthetic agent and the endoscope directed away from the vocal cords and into the esophagus. In some cases, intravenous sedation is useful to supplement the topical anesthesia. Appropriate patient positioning and education to avoid efforts at swallowing further add to the smoothness of this phase of the endoscopy. Patients with large anterior osteophytes of the cervical spine may pose particular risks for perforation, as might Zenker’s diverticula. Attention to these possibilities is mandatory for safe upper endoscopy.

For lower GI endoscopy, the endoscope needs to be introduced into the lumen, most often through the anus, but under some circumstances, through a stoma. Preceding the introduction of the endoscope with a properly performed digital examination is an essential adjunct to safe and comfortable intubation. This provides the opportunity to lubricate the entry, slowly relax the sphincter, and to evaluate the individual anatomy for direction and for any unexpected pathology or sites of potential obstruction.

Endoscopy through a stoma requires some understanding of stomal varieties. A loop stoma is oriented at right angles to the long axis of the bowel. Imprudent introduction of the scope through the stoma can easily cause perforation through the antimesenteric side of the bowel. This is particularly prone to occur in patients whose bowel has been excluded, resulting in atrophy. End stomas are oriented in line with the long axis of the bowel. Digital examination may disclose angulation or kinks in the intra‐abdominal segment of intestine that must be negotiated when introducing the scope.

Methods to assess the phase of introduction of the endoscope include rating of patient comfort, time to intubate, the number of attempts to intubate, and any complications related to the endoscope intubation, anesthesia, and sedation.