1F Esophagus and Deglutition Flashcards
Describe the esophagus
Flattened muscular tube of 18 to 26 cm from upper sphincter to lower sphincter
What is the shape of the esophagus between swallows?
Collapsed
What does the esophagus connect?
Pharynx to stomach
Where is the esophagus relative to the vertebral column?
Anterior of the vertebral column
Where does the esophagus begin relative to the vertebral column?
C5-C6
At what vertebral level does the esophagus traverse the diaphragm?
T10
At what vertebral level does the esophagus end at the cardia of the stomach?
T11
What kind of tissue lines the esophagus?
Non-keratinized stratified squamous epithelium
Why is epithelia continuity critical for normal function?
A breach in the epithelium creates ulcers
Where are the esophageal glands found?
Scattered in the esophageal submucosa
What do esophageal glands provide?
mucus for lubricating the passage of food down the esophagus, augmenting the role of salivary glands
What layers does the wall of the esophagus have?
All like the GI tract except the serosal outer layer. That is mucosa, submucosa, and muscularis
What does the esophagus have instead of the serosal layer?
Thin and poorly defined layer of CT
What does the submucosal vascular plexus of the esophagus include?
Especially large venous spaces
What veins receive venous drainage from the mid and lower esophagus and the submucosal venous plexus?
Collaterals of the left gastric vein, a branch of the portal vein
What are esophageal varices?
When submucosal venous spaces along w/ all the other draining veins of the mid to lower esophagus enlarge
Why would esophageal varices occur?
Due to portal hypertension (usually due to cirrhosis)
What are the risks of esophageal varices?
May rupture with fatal bleeding into the esophageal lumen
What demographic commonly has esophageal varices?
alcoholics, but can also occur with liver cancer
What is the position of the epiglottis when the upper esophageal sphincter (UES) opens?
The epiglottis covers the trachea
What is the oral phase of swallowing?
Voluntary action of collecting the oral contents on the tongue and propelling them backward to the pharynx
What is the pharyngeal phase of swallowing?
Wave of involuntary contraction in the pharyngeal muscles that pushes the material into the esophagus, as the UES relaxes and opens
What happens to respiration when someone is swallowing?
It is inhibited
What is the esophageal phase of swallowing?
Once food enters the esophagus, peristalsis takes over
Swallowing triggers esophageal peristalsis whether or not what is present?
Whether or not food is present. Though presence of food will intensify the peristaltic contractions
What would happen if the primary peristaltic wave fails to move food into the stomach?
The persistence of food in the esophagus will set off secondary peristaltic waves to complete the job
How is the LES contracted?
It is tonically contracted like most sphincters are
What can the tonic contraction be influenced to do?
either relax or contract further
What is achalasia?
the LES fails to relax - food that has been swallowed has difficulty passing into the stomach, and the esophagus above the LES becomes enlarged
What is the danger of achalasia?
A person may aspirate the esophageal contents into the lungs when the person lies down
What is GERD?
When the LES does not close completely after swallowing
What is the common term for GERD?
heartburn or esophigitis
What can esophigitis lead to?
Ulceration and stricture of the esophagus due to scarring
GERD has a strong causal relationship with what?
Esophageal adenocarcinoma
What agents have been shown to diminish the closing strength of the LES, leading to GERD?
Fatty foods, chocolate, ethanol, caffeine, peppermint, spicy foods, citrus fruits and juices, smoking, steroidal based oral contraceptives
What complications can occur from persistent reflux?
mucosal damage that causes edema and erosion of the luminal surface
What is Barrett’s esophagus?
Stricture of the esophagus caused by scar tissue, spasm, and edema. May experience dysphagia and/or odynophagia.
What is the difference b/w dysphasia and odynophasia?
Dysphagia is a difficulty in swallowing and odynophagia is when swallowing is painful
What is Barret’s esophagus characterized by?
a repair process in which squamous mucosa that normally lines the esophagus is gradually replaced by columnar epithelium (metaplasia) - resembling that in the stomach and intestines
What is Barret’s esophagus associated with?
Increased risk of developing esophageal cancer
