Diseases of the equine esophagus Flashcards
(57 cards)
1
Q
anatomy of the equine esophagus: length and parts
A
- Length 125 – 200cm
- Parts:
1. Cervical 2. Thoracic 3. Abdominal
2
Q
esophagus is Surrounded by important anatomical structures:
A
- Trachea
- Jugular vein
- Common Carotid Artery
- Vago-sympathetic trunk
- Left recurrent laryngeal nerve
2
Q
Thoracic and abdominal part of esophagus are close to what nerve? relevance?
A
- Dorsal and ventral Vagal nerve
- Rarely clinically relevant
3
Q
layers of the esophaugs
A
The wall composed 4 layers:
1. Tunica mucosa – mucous membrane
2. Tunica submucosa - submucosal layer
3. Tunica muscularis – muscular layer
4. Tunica adventitia/serosa – fibrous layer
3
Q
arterial supply of the esophaugs?
A
- Cervical part: carotid a.
- Thoracic/abdominal part: bronchoesophageal and gastric a.
4
Q
innervation of the esophaugs?
A
- IX, X cranial n.
- Sympathetic trunk
- Mesenteric ganglion cells
5
Q
Evaluation of esophageal disease; broad methods
A
- physical exam
> visual exam - ultrasonography
- radiography
> several types of studies - endoscopy
6
Q
equipment we need for physical exam and why?
A
Gloves – Rabies list of differential diagnosis
7
Q
clinical signs of esophageal disease we can notice on physical exam
A
Clinical signs manifested by
- Ptyalism
- Dysphagia
- Coughing
- Regurgitation of food, water, saliva through mouth an nostrils
8
Q
what we should check on our physical exam for esophagus issues
A
- visual exam
- Observation of the neck
- Palpation of the neck
> Simple food impaction cervical esophagus
> Crepitation - Oral exam
Can also:
- Auscultation of the thorax
- Sedation
- Nasogastric tube
9
Q
Ultrasound exam cervical esophagus is useful for finding:
A
- Impaction, extramural masses
- Esophageal rupture: gas and free fluid outside the lumen
- Cellulitis
10
Q
when is it important to use radiographs to evaluate esophageal disease? what study should we start with?
A
- Important to complete an esophageal exam in problems other than simple obstruction.
- Start baseline without contrast media.
11
Q
how do we perform a positive contrast esophogram with barium paste? what normal structure will we see?
Sedation?
A
- Barium paste (120mL) oral.
- Normal longitudinal folds of the mucosa.
- Avoid sedation.
12
Q
what is a positive contrast esophogram with barium paste good for visualizing?
A
- Complete obstruction of the esophagus.
- Esophageal stricture.
13
Q
what problems might we be able to see with a baseline esophogeal radiograph
A
- Metallic foreign body.
- Cranial esophageal sphincter
14
Q
how do we perform a positive contrast esophagram with barium liquid? what diseases might we see?
A
- Liquid barium (72% wt/vol with water, 480 ml).
- Cuffed nasogastric tube.
- Esophageal stricture.
15
Q
how do we perform a double contrast study for the esophagus? what is it good for visualizing?
A
- Liquid barium (480 ml) followed
by air. - Examination of mucosal folds.
- Best definition of mucosal lesions.
16
Q
how do we perform a negative contrast esophagram and what area is it good for vs bad for?
A
- Air insuflation.
- Cranial cervical region.
- Not useful for caudal cervical and thoracic esophagus
17
Q
in a positive contrast esophagram, what can swallowing look like?
A
- Swallowing produces false signs of esophageal stricture
18
Q
purpose and use of endoscopy to investigate esophageal lesions? how do we use the endoscope?
A
- Define the severity and extent of the lesions observed in radiography
- Endoscope 200cm or longer.
- Start with the endoscope fully inserted.
- Insufflate the esophageal lumen.
- Slow withdrawal.
- After each swallow clear the scope and dilate before withdrawal.
19
Q
Most common obstructive esophageal disease?
A
Impaction ”Choke”
20
Q
Impaction ”Choke” is associated usually with what?
A
- Associated with ingesta or bedding.
21
Q
clinical signs of impaction “choke”
A
- Ptyalism
- Dysphagia
- Coughing
- Regurgitation of food, water and saliva from the mouth and nostrils
22
Q
Impaction ”Choke”;
Attempts of ingestion are followed by:
A
- Odynophagia – painful swallowing
- Repeated extension of the head and neck. - Distress, agitation
23
when investigating Impaction ”Choke”;
Intermittent signs of choke followed by periods of relief may indicate what?
Intermittent signs of choke followed by periods of relief may indicate a disease other than a simple impaction.
24
Impaction ”Choke”;
problems associated with cases of long duration
- Anorexia.
- Electrolyte imbalances.
- Dehydration.
25
Impaction ”Choke”; what frequently followis esophageal obstruction? when can clinical signs begin? how can we investigate this?
- Aspiration pneumonia frequently follows esophageal obstrcution.
- Clinical signs can be present 1 day after the onset of choke
>Ultrasonographic/radiographic exam
26
Impaction ”Choke”; what we need to do on physical exam to investigate?
- Observation of the neck.
- Palpation of the neck > Crepitation.
- Oral exam.
- Thoracic auscultation.
27
what kind of radiographic study would we generally use for impaction "choke"
- No constrast.
28
what would we see in impaction choke on endoscopic exam?
- esophagus filled with ingesta
29
Impaction ”Choke”; usual procedure to treat
- Under sedation
> Xylazine 0.25-0.5 mg/kg IV.
> Detomidine 0.01-0.02 mg/kg IV
- Nasogastric intubation.
> With the head and neck down
- Gentle lavage > warm water.
- Do not push.
30
alternative techniques to treat impaction choke
- Cuffed endotracheal tube.
- Lavage under pressure with stomach pump.
- External massage.
- Endoscopic basket.
31
if we have no success with our initial treatment of impaction choke, what do we do?
- Muzzle the horse
- Stall without bedding
- off feed/water
- Repeat treatment in 8-12hours
If there is no success:
- Surgical treatment Esophagotomy
32
Impaction ”Choke”
Adjunctive therapies and retionale:
- Acepromazine (0.05mg/kg IV)
> esophageal relaxation.
- Oxytocin (0.11 and 0.2IU/kg IM)
> short term esophageal relaxation.
- N-butylscopolammonium bromide (0.3 mg/kg IV)
> smooth muscle relaxation
- Esophageal instillation of lidocaine (30-60mL 1%)
> smooth muscle relaxation.
33
Impaction ”Choke”
Systemic effects from prolonged loss of salivary water/electrolytes:
- Dehydration
- Hyponatremia
- Hypochloremia
- Hypopotassemia.
- Metabolic alkalosis
34
Impaction ”Choke”
Treatment (after procedure):
- Polyionic fluids with electrolyte supplementation
- Broad spectrum antibiotic therapy
- NSAID Flunixin meglumine – judicious use
> reduce the development of strictures
> can worsen esophageal mucosa injury
- Sucralfate (20mg/kg PO q 6h) – healing of esophageal ulceration
()
- Food withheld 24-48h or longer after resolution
- Introduce soft food > pelleted feed mashes
> small amounts, gradually increase
> transition to high quality roughage diet over 7 – 21 days depending on the esophageal damage.
35
Impaction ”Choke”
Rate of reobstruction and prognosis for survival
Rate of reobstruction – 37%
Prognosis for survival – 78-88%
- Horses may require permanent diet changes.
36
Impaction ”Choke”
Complications:
- Pharyngeal inflammation
- Mucosal bruising
- Mucosa stripped off the submucosa
- Stricture
- Ruptured esophagus.
- Periesophageal abscess.
- Fistula
- Esophageal diverticulum
37
what is an esophageal stricture? what is it secondary to?
- Narrowing of the esophageal lumen.
- Secondary to:
> External trauma
> Internal trauma especially after impactions
38
Three types of strictures based on the anatomic location:
- Type I mural lesions – involve the
adventitia and muscularis
- Type II esophageal rings or webs – involve mucosa and submucosa
- Type III annular stenosis – all layers
39
Strictures
Clinical signs:
- Similar to simple impactions
40
Strictures
diagnostics, timeline for medical management
- contrast radiographs, endoscopy
Following a simple impaction:
- Maximal reduction of the lumen occurs within 30 days of the impaction
- Medical management is recommended first – the esophagus continues to remodel for up to 60 days following ulceration.
41
Strictures
Medical management:
- Balloon dilation
42
Strictures
Surgical treatment options
- Esophagomyotomy
- Partial/complete resection and anastomosis
- Creation of a traction diverticulum
- Patch grafting
- Esophagostomy
43
Esophageal rupture is secondary to:
- Long standing obstruction
- Repeated or aggressive nasogastric intubation
- Foreign body perforation
- External trauma to the cervical area
– kick
- Extension of an infection
44
Esophageal rupture clinical signs?
- Discomfort, depressed
- Head/Cervical swelling
- Subcutaneous emphysema
– swallowed air escapes - Cellulitis
45
esophageal rupture diagnostics
- Endoscopy
- Positive contrast esophagram
46
in a case of esophageal rupture, why is it
important to establish drainage on the ventral midline?
If not, complications that can occur:
- Mediastinitis, pleuritis, septicemia
- Horner’s syndrome, laryngeal hemiplegia
- Jugular thrombosis, carotid rupture
47
esophageal rupture treatment?
- Surgical repair within 12 hours of perforation
- In case of infection, contamination with ingesta
> Drainage needs to be provided
> Second intention healing
- Antibiotic, anti-inflammatory and fluid therapy + elytes
48
how can we feed a horse that has undergone surgery for esophageal rupture while it heals?
- Feed through a tube located in
the defect
- Feed through a tube located distally (esophagostomy)
49
2 types of esophageal divertilculi
A. Traction or true diverticulum
B. Pulsion or false diverticulum
50
Traction or true diverticulum
- how does this arise? what does it cause?
- where does it develop?
* Acquired lesion that result from
contraction of periesophageal scar
tissue.
* Cause outward rotation and tenting of
all layers
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* Develops at the site of esphagostomy
* Second intention healing sites
51
Pulsion or false diverticulum
- definition?
- cause?
* Protrusion of mucosa and submucosa
through a defect in the esophageal
muscularis
* Caused by changes in pressure
52
how will the neck look on imaging for a traction diverticulum vs pulsion diverticulum?
traction - wide neck
pulsion - narrow neck
53
Pulsion or false diverticulum
- progression?
- possible sequelae risks?
- Tx?
* Tends to enlarge progressively
* Risk of obstruction and rupture
* Surgery is indicated
54
Traction diverticulum
- signs? Tx?
* Few clinical signs
* Seldom requires treatment
55
surgical treatment options for pulsion /false diverticulum?
* Diverticulectomy
* Mucosa inversion - preferred
