Small Animal Veterinary Medicine: Dz Of The Esophagus

Front 1

What are the clinical signs of esophageal disease depend on?

Back 1

depend on severity, location, chronicity of the problem and presence of secondary problems

Front 2

What is the hallmark of esophageal dz?

Back 2

Regurgitation

Front 3

What are other clinical signs of esophageal disease?

Back 3

Repeated Swallowing - more often associated with pharyngeal disease
Salivation/Drooling
Respiratory signs - coughing, dyspnea
Can be due to aspiration pneumonia or bronchoesophageal fistula
Bulging of cervical esophagus in thoracic inlet
Weight loss
Anorexia or voracious appetite

Front 4

Why is it impt to obtain a proper history?

Back 4

 Differentiate regurgitation, dysphagia, vomiting
 Age
 Young
 Congenital megaesophagus
 Foreign bodies
 Vascular ring anomalies
 Adult - idiopathic or acquired megaesophagus
 Ability to retain liquids vs. solids
 Liquids can pass through partial obstructions
 Presence of peripheral neuromuscular weakness
 Exposure to toxins, foreign bodies, caustic agents, etc.
 Acute vs. Chronic
 Acute - foreign body, caustic agent, etc.
 Chronic - neuromuscular disease

Front 5

What are the histological layers of the esophagus?

Back 5

Adventitia-Thin fibrous tissue covering the esophagus Muscularis
Submucosa - contains mucus glands
Mucosa - stratified squamous epithelium

Front 6

What is the difference btw the muscularis layer in dogs and cats?

Back 6

Dog- Striated muscle throughout the entire length (2 oblique spiraling layers)
Cat -Striated muscle in proximal 2/3 and smooth muscle in distal 1/3

Front 7

What is the innervations carried by the vagus to the esophagus?

Back 7

a. Visceral afferent nerves (sensory to submucosa)
b. Somatic motor nerve to striated muscle
c. Autonomic nerves to smooth muscle in cats and LES Smooth muscle

Front 8

What is the function and purpose of the lower esophageal sphincter?

Back 8

a. A functional (not anatomic) smooth muscle sphincter
b. Maintains high pressure zone

Front 9

What agents both enternal and external cause the body to relax the LES?

Back 9

a. Atropine
b. Diet - high fat diets
c. G.I. hormones - cholecystokinin, secritin, glucagon
d. General anesthesia
e. Preanesthetics - acepromazine, morphine, diazepam

Front 10

What agents both enternal and external cause the body to increase tone of the LES?

Back 10

a. Metoclopramide
b. Bethanechol - -adrenergic agonist
c. Gastrin
d. Diet - high protein diets

Front 11

What are the drugs that increase esophageal motility in a dog and cats?

Back 11

Metoclopramide and cisapride may have some effect in the cat because smooth muscle. There are no drugs proven to increase esophageal motility in the dog

Front 12

What is the action of primary paristalsis in the esophageal phase of swallowing and what is it stimulated by?

Back 12

a. A peristaltic wave originating at the UES and usually progresses without interruption to the GE junction
c. Stimulated by (or is a direct continuation of) pharyngeal peristaltic contractions

Front 13

What is the action of secondary paristalsis in the esophageal phase of swallowing and what is it stimulated by?

Back 13

a. A peristaltic wave originating proximal to one or more boluses present within the esophagus (usually cervical esophagus)
b. Stimulated by tactile stimulation and esophageal distention from bolus

Front 14

In the reflex pathway of the esophageal phase the sensory receptors in esophagus stimulate visceral afferent pathways in vagus to nucleus solitaries a defect in this area is believed to be responsible for what?

Back 14

Idiopathic megaesophagus

Front 15

What is checked under physical exam for esophageal disease?

Back 15

Cervical palpation - may reveal dilated esophagus, mass, or foreign body
Respiratory evaluation - nasal discharge or respiratory crackles

Front 16

What exam is often very helpful in identifying an associated neuromuscular etiology for megaesophagus?

Back 16

A neurologic exam

Front 17

What are the diagnostic techniques used to evaluate esophageal disease?

Back 17

radiology and endoscopy are the mainstay of diagnostic procedures for the diagnosis of esophageal diseases.

Front 18

What are the different types of radiographic examinations and what do the evaluate?

Back 18

Survey Films :
Both cervical and thoracic esophagus should be evaluated (normal esophagus not routinely visualized, Abnormal -Luminal air is suggestive of esophageal disease and may outline mucosal irregularities or indicate luminal distension)
*Esophagus may be evident with pneumomediastinum
Esophagram:
Liquid barium sulfate suspension - demonstrates esophageal luminal diameter
Barium paste - demonstrates mucosal detail
(not recommended for perforation and in dehydrated animals)

Fluoroscopy:
Primary procedure for evaluating esophageal motility
Normal - will visualize normal primary and secondary peristalsis
Abnormal - evidence of dilation, lack of primary or secondary peristalsis

Front 19

What is the advantage of endoscopy?

Back 19

Allows visualization of mucosal surface and, if needed, biopsy of the esophageal mucosal lesions
Offers a method for removal of many esophageal foreign bodies

Front 20

What is esophageal manometry used for?

Back 20

Evaluates esophageal and sphincter pressure and esophageal motor function

Front 21

What are the 2 types of esophageal hypomotility (megaesophagus)?

Back 21

Generalized - Hypomotility and/or dilation of the entire esophagus
Segmental - Dilation of a segment of the esophagus

Front 22

What are the 3 etiologies of generalized hypomotility?

Back 22

Congenital - an idiopathic generalized megaesophagus that manifests clinical signs at or near weaning
Acquired - a generalized megaesophagus that develops secondary to a demonstrable underlying disease process
Idiopathic - a generalized megaesophagus occurring in the adult in which an underlying etiology for the megaesophagus is not detectable

Front 23

What is the most common etiology of segmental dilatation?

Back 23

Secondary effect of focal esophageal obstruction or dysfunction

Front 24

What are the clinical signs of esophageal hypomotility (megaesophagus)?

Back 24

Regurgitation, weight loss, respiratory signs
Acquired megaesophagus often has signs associated with the primary disease (ex. neuromuscular signs)

Front 25

How would one diagnose esophageal hypomotility (megaesophagus) all three etiologies?

Back 25

Congenital - based on age of onset and presence of a generalized megaesophagus
Acquired - based on confirming one of the many diseases associated with acquired megaesophagus
Idiopathic - based on exclusion of all known causes for acquired megaesophagus

Front 26

What is the treatment for esophageal hypomotility?

Back 26

Clinical management (feed and elevate head for 15 mins or temp tube gastrotomy)
Medical management
drugs that increase motility-metoclopamide- ineffective
drugs that dec LES pressure- atropine, nifedipine – ineffective
immunosuppressive drugs- if caused by immune mediated dz
Surgical management (dec LES competency- only use when pressure is elevated)

Front 27

What is the prognosis of esophageal hypomotility (megaesophagus) all three etiologies?

Back 27

Congenital - good to guarded - approximately 45% recovery
Acquired - depends on underlying disease and severity/duration of the megaesophagus
Idiopathic - poor to grave. Depends on response to therapy.

Front 28

What is the etiology of vascular ring anomalies?

Back 28

Etiology - obstruction of esophagus from an extraluminal constriction caused by congenital anomalies of the aortic arch and its branches
Most common cause in dogs and cats is persistent right aortic arch

Front 29

What is the clinical signs of vascular ring anomalies?

Back 29

Compatible with esophageal obstruction
Acute onset of signs at weaning

Front 30

What is used to diagnosis vascular ring anomalies?

Back 30

Radiographs or endoscopy indicating constriction of the esophagus at the base of the heart
Differential Diagnosis - intrinsic stricture, diverticulum or foreign body

Front 31

What is the treatment of vascular ring anomalies?

Back 31

Surgical correction- poor patient condition complicates surgery
Often a permanent dilatation cranial to the area of constriction
Dilation caudal to the constriction can occur as a result of neuromuscular damage at surgery

Front 32

What is the prognosis of vascular ring anomalies?

Back 32

fair to poor, depending on severity of esophageal dilation

Front 33

What is the locations of esophageal FB?

Back 33

Common sites of obstruction include thoracic inlet, base of heart and distal esophageal hiatus, cervical esophagus for hooks (Esophageal perforation is a possible complication)

Front 34

What is the clinical signs of esophageal FB?

Back 34

Show signs of esophageal obstruction plus discomfort and labored swallowing movements
Labored breathing if foreign body is large and causes airway compression

Front 35

What is used to diagnosis esophageal FB?

Back 35

Radiographs or endoscopy

Front 36

What is the treatment of esophageal FB?

Back 36

Removal by esophagoscopy
Pushing object into stomach
Surgical resection
Always re-evaluate for esophageal rupture after removal of the foreign body

Front 37

What is the complications of esophageal FB?

Back 37

Esophageal perforation, mediastinitis, pleuritis, esophagitis, mucosal lacerations or ulcers
Stricture formation
Bronchoesophageal fistulas
Pericarditis

Front 38

What is the etiology of esophagitis?

Back 38

Chemical irritants
Thermal injuries
Vomiting, acute or chronic
Foreign bodies
Gastroesophageal reflux
Neuromuscular disease, anesthesia, neoplasia, hiatal hernias, pharyngostomy tubes

Front 39

What is the clinical signs of esophagitis?

Back 39

May be mild or non-existent
Typical signs of esophageal disease if severe

Front 40

What is used to diagnosis esophagitis?

Back 40

requires endoscopy

Front 41

What is the treatment of esophagitis?

Back 41

Correct underlying cause
Neutralize acids or bases
Antacids, local or systemic
Low fat diets
Metoclopramide

Front 42

What is the etiology of esophageal strictures?

Back 42

Etiology - requires damage to submucosa or muscularis layers
Surgery
Foreign body
Perforating trauma
Caustic agents
Esophagiti

Front 43

What is used to diagnose esophageal strictures?

Back 43

Rdiaology and endoscopy

Front 44

What is the treatment of esophageal strictures?

Back 44

Mechanical Dilatation
Bougienage
Balloon dilators
. Surgery - not routinely recommended; high incidence of post-operative stricture

Front 45

What is the etiology of periesophageal strictures?

Back 45

Vascular ring anomalies (see previous discussion)
Cervical tumors - thyroid tumors, squamous cell carcinoma
Foreign body abscesses
Fungal granuloma
Mediastinal masses
Thoracic cavity tumors - heart base, thymomas
Hialar lympadenopathy

Front 46

What is used to diagnose periesophageal stricture?

Back 46

Radiographic evaluation - will show compression and may demonstrate mass
Endoscopy - shows normal mucosa in the presence of the stricture

Front 47

What is the treatment of periesophegeal stricture?

Back 47

Directed at extraluminal mass

Front 48

What is the etiology of esophageal diverticula?

Back 48

Pulsion - esophagitis, esophageal stenosis, foreign bodies, vascular ring anomalies, hiatal hernia, megaesophagus
Traction - resolving extraesophageal inflammatory processes

Front 49

What are the types of esophageal diverticula?

Back 49

Aquired
Congenital
Pulsion diverticula - results from increased intraluminal pressure pushing esophageal wall out
Traction - secondary to extraesophageal inflammation that forms a fibrous adhesion to adventitia and then contracts, pulling on the esophageal wall

Front 50

What is the treatment of esophageal diverticula?

Back 50

Surgical resection if large

Front 51

What is the etiology of esophageal fistula?

Back 51

Formation of an open connection between the esophagus and an airway
Tracheal, bronchial, or pulmonary connection
Congenital or acquired

Front 52

What is the pathogenesis of esophageal fistula?

Back 52

usually associated with a history of foreign body obstruction

Front 53

What is used to diagnose esophageal fistulas?

Back 53

contrast radiography is the diagnostic test of choice

Front 54

What is the treatment of esophageal fistulas?

Back 54

Surgical closure

Front 55

What are common etiologies of esophageal neoplasia?

Back 55

Hiatal hernia - herniation of abdominal esophagus, GE junction and stomach into the thoracic esophagus
Periesophageal hiatal hernia - herniation of a part of the stomach through a diaphragmatic defect adjacent to the esophagus
Gastroesophageal intussusception - invagination of entire stomach into the esophagus

Front 56

What is the forms of hiatal disorders?

Back 56

Hiatal hernia
Periesophageal hernia
Gastroesophageal intussusceptions

Front 57

What is a hiatal hernia?

Back 57

herniation of abdominal esophagus, GE junction and stomach into the thoracic esophagus

Front 58

What is a periesophageal hernia?

Back 58

herniation of a part of the stomach through a diaphragmatic defect adjacent to the esophagus

Front 59

What is a gastroesophageal intussuception?

Back 59

invagination of entire stomach into the esophagus

Front 60

What is the clnical signs of hiatal disorder?

Back 60

regurgitation, hematemesis, respiratory distress, cyanosis

Front 61

What is used to diagnose hiatal disorder?

Back 61

Radiographic evaluation

Front 62

What is the treatment of hiatal disorder?

Back 62

Surgical repair