Esophageal Physiology Flashcards
Through what does the esophagus pass to reach the stomach?
The right crus of the stomach.
What is the physiological function of the esophagus?
(1) Propel swallowed food into the stomach.
(2) Prevent gastroesophageal reflux.
(3) Vomiting and belching.
What muscles comprise the upper esophageal sphincter?
(1) inferior pharyngeal constrictor.
(2) cricopharyngeus.
(3) cervical esophagus.
What is the primary activator of esophageal activity?
The act of swallowing.
What part of the brainstem receives sensory input from the esophagus?
The nucleus solitarius.
What part of the brainstem controls smooth muscle in the esophagus?
The dorsal motor nucleus.
What part of the brainstem controls skeletal muscle in the upper esophagus and diaphragm?
The nucleus ambiguus.
Describe the neural activity involved in peristalsis.
Swallowing activates noncholinergic inhibitory pathways throughout the esophagus (though these pathways predominate in the caudal end). Sequential activation of the cholinergic excitatory pathways (which predominate in the rostral end) then occurs. Graded delays in contraction result in peristalsis.
J: This refers to the perception that there is an obstruction to the normal passage of swallowed material.
What is dysphagia?
J: This refers to the sensation of pain when swallowing.
What is odynophagia?
J: This refers to feeling of a “lump in one’s throat,” though swallowing can be performed normally.
What is globus?
What is heartburn?
A sensation of burning rising from the stomach or lower chest up towards the neck.
What tests are used to evaluate esophageal function?
(1) barium esophagram.
(2) endoscopy.
(3) manometry.
What is achalasia?
A decrease in myenteric neurons, particularly inhibitory NO-releasing neurons, in the distal esophagus, arising after an auto-immune, viral or neurodegenerative insult.
How does achalasia appear microscopically?
Either (1) inflammation of myenteric nerves and ganglion, or (2) fibrosis with minimal residual inflammation.
How does achalasia present on endoscopy?
(1) dilation
(2) retained saliva, liquid and undigested food
(3) absence of mucosal stricturing
How does achalasia present on manometry?
(1) insufficient LES relaxation
(2) loss of peristalsis
What is in the ddx for achalasia-like symptoms?
(1) esophageal cancer
(2) metastases from lung, pancreatic or breast cancer
(3) benign mesenchymal tumors
(4) pancreatic pseudocysts
(5) amyloid deposition
How is achalasia treated?
(1) botulinum toxin
(2) pneumatic dilation
(3) myotomy (Heller or POEM)
What is GERD?
A condition which develops when reflux of stomach contents causes heartburn and adversely effects a person’s well being.
What are causes of GERD?
(1) transient relaxation of the LES
(2) hiatal hernia
(3) hypotension of the LES
Why is obesity associated with GERD?
Obesity increases intra-abdominal pressure, thus increasing the likelihood of a hiatal hernia.
How is GERD treated?
(1) lifestyle changes
(2) antacids
(3) H2 blockers or PPIs
(4) anti reflux surgery
J: This refers to intestinal metaplasia in the distal esophagus.
What is Barrett’s esophagus?
What are risk factors for Barrett’s esophagus?
(1) aging, Caucasian male
(2) long history of reflux
(3) smoking, obesity
How is Barrett’s esophagus treated?
(1) endoscopic mucosal resection
(2) radiofrequency ablation
What is the primary concern with Barrett’s esophagus?
It is a potential precursor lesion for esophageal cancer.
What are the symptoms of eosinophilic esophagitis?
(1) dysphagia
(2) food impaction
(3) heartburn
(4) odynophagia
What immune cells and cytokines are elevated in eosinophilic esophagitis?
(1) eosinophils, TH2 and mast cells
(2) IL-4, IL-5, IL-13
How is eosinophilic esophagitis treated?
(1) diet change
(2) pneumatic dilation
(3) PPIs
(4) topical steroids
