Overview
Transnasal flexible esophagoscopy is a helpful tool that reduces diagnostic delays and the need for endoscopy under general anesthesia. [1] It is a safe and well-tolerated procedure that can be performed under local anesthesia and in the outpatient setting. [2, 3, 4] The procedure can be performed for diagnostic and therapeutic purposes. Transnasal esophagoscopy requires no sedation. [2, 3] It is a highly cost-effective tool that is easily learned. [3, 5]
Indications
The indications for transnasal flexible esophagoscopy include the following:
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Evaluation of a possible foreign body [9]
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Procedures such as dilation of a stricture or injection of botulinum toxin in the lower esophageal sphincter [16]
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Cough [6]
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Extrinsic esophageal compression [6]
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Candidiasis [6]
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Foreign body removal [18] - This was once considered as a contraindication, but transnasal esophagoscopy is now being increasingly used as diagnostic and therapeutic tool for the extraction of foreign bodies with quick discharge of patients in less than an hour. [19]
Contraindications
Transnasal esophagoscopy may be contraindicated in patients with bleeding diathesis or abnormal coagulation profile. [20]
Anesthesia
See the list below:
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After positioning the patient and obtaining informed consent, start examining the nasal cavities.
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Spray the more patent nostril with a 1:1 ratio of oxymetazoline (Afrin) 0.05% and lidocaine (Xylocaine) 4%.
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Then spray the oropharynx with lidocaine (Xylocaine) 10% and ask the patient to swallow immediately.
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Lubricate the endoscope with viscous lidocaine 2%. [9]
Equipment
See the list below:
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Local anesthetic and oxymetazoline sprays
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Viscous lidocaine
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A distal video chip transnasal endoscope with a camera built into its tip (eg, Pentax 80K series digital video endoscope [5.1-mm diameter]) [2]
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Suction, irrigation, and insufflation all attached to the endoscope (in the distal video chip endoscope) or linked to the EndoSheath (in an add-on camera transnasal endoscope) [2]
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Television monitor
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Video cassette recorder
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Light source
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Pentax biopsy forceps
Positioning
See the list below:
Technique
See the list below:
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Explain the procedure to the patient and obtain informed consent.
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Check all equipment before beginning the procedure (see image below).
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Pass the endoscope parallel to the floor of the nose or between the middle and inferior turbinates (see image below).
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When the nasopharynx is reached, turn the flexible scope downward (see images below). Closely observe the nasopharynx, hypopharynx, and glottis for any abnormalities. [21]
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As soon as the hypopharynx is reached, ask the patient to flex his head forward to reach his chest. At that time, ask the patient to swallow. This relaxes the cricopharyngeus. [20] See images below.
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Under direct visualization, advance the scope through the cervical esophagus toward the cardia. Asking the patient to phonate a vowel facilitates entry of the scope through the esophagogastric junction. This maneuver relaxes the lower esophageal sphincter and also allows movement of the diaphragm. [21]
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Rotate the scope 360º while angulating upward to look for the gastroesophageal junction and the gastric cardia. This is called the J maneuver. [21] See images below.
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Remove the endoscope gently, using intermittent insufflation and suction, while taking close look at the esophageal lumen (see images below). [21]
Pearls
Compared to the transoral esophagogastroduodenoscopy (EGD), the transnasal route has the advantage of not stimulating the uvula and the posterior part of the tongue, thus not stimulating the gag reflex. [22]
Most complications encountered in regular sedated oral endoscopy are usually due to sedation. Cardiopulmonary complications account for over 50% of complications. [5]
Complications
Complications may include the following:
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Advancement of the scope past the base of the tongue.
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Advancement of the scope intranasally parallel to the nasal floor.
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360-degree rotation of the scope to view the gastroesophageal junction (J maneuver).
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Checking all instruments is crucial before starting the endoscopy.
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Advancement of the scope at the level of the nasopharynx.
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Air insufflation to view the stomach.
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Slow withdrawal of the scope with careful attention to the monitor.
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Flexible endoscope passing into the hypopharynx.
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Air insufflation in the stomach.
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Scope passing through the cricopharyngeus as the patient is asked to swallow.
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Slow withdrawal of the scope allows careful visualization of the esophageal mucosa.
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Scope at the level of the gastroesophageal junction and stomach.