Esophageal endoscopy technique

The endoscopist stands on the left, facing the patient. The patient's head is slightly tilted back. A mouthpiece is put on the fibroendoscope, the assistant fixes the patient's head. The endoscopist grasps the fibroendoscope with his right hand and holds it like a pencil. Before inserting the endoscope into the esophagus, its distal end is slightly bent backwards in accordance with the curvature of the oropharynx. The patient is asked to swallow at the height of a small inhalation. At this point, the endoscope is carefully advanced into the esophageal cavity. Great care must be taken when passing from the pharynx to the esophagus. Due to the contraction of the lower constrictor of the pharynx, the narrowest, cricopharyngeal narrowing of the esophagus is formed, the so-called mouth of the esophagus according to Killian, measuring 23 mm in diameter and 17 mm in the anteroposterior direction. Some resistance is always felt here, and therefore the instrument should be passed smoothly, since perforation of the esophagus is possible. To facilitate the advancement, at the moment of swallowing the device is gently inserted into the esophagus, releasing at this moment the lever that bends the end of the endoscope. The endoscope is inserted into the pharyngeal cavity strictly along the midline. It should be remembered that the end of the device easily deviates from the midline and can rest against the pear-shaped pocket of the pharynx, formed by the so-called inferior pharyngeal ridge - a fold of the mucous membrane on the inner surface of the esophagus according to the location of the cricothyroid muscle. Violence in such cases is not allowed - it is necessary to carefully correct the situation.

As the patient swallows, the endoscope is carefully passed through the upper esophageal sphincter and then advanced under direct visual control. Free advancement of the device, absence of coughing and abrupt change in voice indicate its location in the esophagus. During this period, only a bright red field of vision is visible in the eyepiece.

In the cervical esophagus, the longitudinal folds of the mucous membrane touch each other at their tops. It is possible to straighten the folds and examine the mucous membrane of this section only with intensive air injection; it is difficult to achieve complete straightening of the folds. At the moment when the esophagus has easily straightened under the action of air, it can be stated that the end of the endoscope has reached the thoracic esophagus. Here, the mucous membrane becomes smooth, pink, the lumen of the esophagus acquires a rounded shape. Below the level of the aortic arch (at a distance of 25 cm from the edge of the upper incisors), the esophagus slightly deviates to the left and forward. The esophagoscope should be advanced along this deviation. The place where the esophagus passes through the diaphragm is determined by the characteristic annular narrowing of the esophagus and a slight expansion. The abdominal section of the esophagus is well straightened by air and is a funnel, the bottom of which is the esophageal-gastric junction. The endoscopic reference point for the latter is the Z-line (Fig. 14) - the transition zone between the esophagus (its mucous membrane is pink) and the stomach (the mucous membrane is red). Normally, the Z-line is located 0-2 cm above the cardia.

After free passage of the middle and lower parts of the esophagus, the endoscopist may feel slight resistance caused by spasm of the circular muscles of the cardiac part of the stomach. In this case, a small amount of air should be introduced by pressing the balloon and the endoscope should be pushed deeper without force. From the moment the endoscope passes through the esophagogastric junction, air is periodically supplied to the stomach, which ensures good visibility. In this case, a gradual change in the color of the field of vision can be observed: it becomes pale, becomes orange-yellow and soon an image of the gastric mucosa appears. Introduction of an excessive amount of air into the stomach can cause painful sensations, regurgitation, and vomiting in the person being examined.

The esophagus is examined both during the introduction of the endoscope to the stomach and when it is removed. For successful diagnosis of various diseases during esophagoscopy, it is necessary to study not only the integrity of the mucous membrane, its color, mobility, folding, but also the function of the esophagus - the peristalsis of its walls, their change depending on breathing and heart contractions, the presence of rigidity of the walls that do not straighten when air is introduced.

When using a fiber endoscope with lateral optics, it is not possible to visually control its progress along the esophagus (this part of the procedure is performed blindly). Therefore, if an esophageal disease is suspected, the examination should be performed with an endoscope with end optics.