Esophagus: Regurgitation & Dysphagia Flashcards
describe the anatomy of the esophagus from pharynx to the stomach
starts dorsal to larynx
runs of left side, dorsal to trachea in mediastinum
through esophageal hiatus in diaphragm
enters stomach at cardia
what are the two sphincters of the esophagus (2)
- upper esophageal sphincter (UES): cricopharynx
- lower esophagus sphincter (LES): cardia of stomach
what are the layers of the esophagus (4)
- mucosa
- submucosa
- muscularis: striated in the dog and striated and smooth in cats
- adventitia (no serosa)
what innervates the esophagus
the vagus nerve (efferent and afferents)
how is normal swallowing occur
highly coordinated and largely involuntary
Upper esophageal sphincter relaxes and food moves into the proximal esophagus. Peristalsis than moves food down esophagus
Lower esophageal sphincter relaxes before the food gets there and food can empty into stomach. Then contracts to prevent reflex
If primary peristaltic wave fails to get food down a secondary wave will move the food down generated by esophageal distention
what is dysphagia
difficulty swallowing
what is pharyngeal dysphagia
try and swallow repeatedly but gag, retch, struggle to drink and may eject food from mouth (immediately after eating)
what are the causes of pharyngeal dysphagia
failure of UES to relax (achalasia) OR
incoordination between pharyngeal contraction and UES relaxation (asynchrony)
what are the signs of esophageal dysphagia
usually only 1 swallowing attempt, may or may not be able to drink
may bring up food at any time after eating
what is regurgitation
passive evacuation of food and/or fluid from esophagus
what causes regurgitation
local events within esophagus
may be due to structural disease, obstruction or functional disease
how do you distinguish between regurgitation and vomiting
is there prodromal nausea with vomiting or regurgitation
usually with vomiting
not with regurgitation
is there retching/abdominal effort with vomiting or regurgitation
with vomiting yes
not with regurgitation
is there food material produced with vomiting or regurgitation
sometimes food with both
what is the character of the food material produced with vomiting or regurgitation
usually digested with vomiting
usually undigested with regurgitation
is there bile with vomiting or regurgitation
sometimes with vomiting
not with regurgitation
what is the pH of vomit and regurgitation material
acidic/alkali with vomiting
alkali with regurgitation
what is aspiration pneumonia
food or water inhaled into lungs
causes chemical injury followed by secondary infection
what are the signs of aspiration pneumonia (6)
- soft cough
- dyspnea
- tachypnea
- pyrexia
- lung crackles
- +/- nasal discharge
what are the signs of aspiration pneumonia on rads
radioopacity of the ventral lung fields with air bronchograms
what are risk factors of aspiration pneumonia
regurgitation or dysphagia
what is the treatment for aspiration pneumonia
- oxygen therapy if needed
- fluid therapy if needed
- broad spectrum antibiotics
- nebuilization
- coupage
what are signs of esophageal disease (9)
- regurgitation
- dysphagia
- +/- odynophagia
- +/- ptyalism
- +/- ravenous or reduced appetite
- +/- weight loss
- +/- dehydration
- +/- cervical swelling
- +/- respiratory signs due to secondary aspiration pneumonia
what are obstructive esophageal diseases (8)
- vascular ring anomaly (VRA)
- foreign body
- stricture
- hiatal hernia
- diverticulum
- perioesophageal obstruction
- gastro esophageal intussception
- parasitic granuloma
what are functional esophageal diseases (5)
- megaesophagus (MO) (congenital or acquired; primary or secondary)
- esophagitis
- gastroesophageal reflux
- lower esophageal sphincter achalasia-like syndrome (rare)
- cricopharyngeal achalasia or asynchrony (rare)
what are the clinical examination abnormalities that can be seen with esophageal diseases (5)
- hypersalivation
- poor body condition
- bulging in neck (food or air)
- muscle atrophy/weakness (neuromuscular disease)
- respiratory signs (aspiration pneumonia)
what esophageal abnormalities can be seen on rads (6)
- radioopaque foreign body
- dilation of esophagus
- hiatal defects
- peri-esophageal massess
- pulmonary changes
- pneumomediastinum/mediastinitis/pleural effusion
what is contrast radiography useful for
- luminal obstruction
- mucosal irregularity
- significant alterations in motility
- hiatal hernia
what are the risks for contrast rads
aspiration pneumonia –> severe problems
what is fluoroscopy useful for
pharyngeal disorders
sublte esophageal motility disorders
what can you observe with fluoroscopy (5)
- oral phase
- esophageal transit time
- pooling contrast
- stalling of boluses
- gastroesophageal reflux
what does esophagoscopy allow assessment of (4)
- lumen and mucosa (obstructions, inflammation, perforation, hiatal hernia, dilation)
- biopsy or cytology sampling (rare)
- foreign body removal
- balloon dilation of strictures
what can be seen on hematology with esophageal diseases
often normal
but if aspiration pneumonia –> leukocytosis, left shift neutrophilia, monocytosis
what can be seen on biochemistry with esophageal diseases
often normal
what are the difficulties with esophageal surgery (5)
- risk of AP on induction of GA
- thoracotomy for intrathoracic esophagus
- risk of contamination of thoracic cavity
- healing challenging
- fixed length
what is esophagotomy
incision into lumen
what is esophagectomy
removal of portion
what is esophagostomy
creation of opening for feeding tube
how is esophagotomy done (7)
- stabilize patient
- longitudinal incision
- two layer closure
- submucosa is holding layer (always include in sutures)
- simple interrupted suture pattern (do not leave knots on the wall)
- check closure integrity
- treat esophagitis post-operatively
what is a congenital vascular ring anomaly
causes significant narrowing and obstruction of esophagus
what are the causes of congenital vascular anomaly
persistant right aortic arch (most common)
right aortic arch becomes functional aorta instead of left fourth arch
various other less common vascular anomalies can occur
what are the breed dispositions of vascular ring anomaly
GSDs and irish setters
start regurgitating when eaned
often have weight loss and stunting
how are congenital vascular ring anomalies treated
surgery to transect ligamentum arteriosum
treat AP and improve body condition before surgery
>90% have significant clinical improvement
some have ongoing problems with esophageal motility –> regurgitation
what are common sites of obstruction of foreign bodies (3)
- thoracic inlet
- heart base
- just cranial to diaphgram (most common)
what are the signs of acute onset foreign body obstruction (5)
- regurgitation
- dysphagia
- odynophagia
- gagging
- hypersalivation
what can be seen on clinical examination with foreign body obstruction
- halitosis
- cervical FB may be palpable
- systemic signs suggest AP or perforation
how are foreign bodies diagnosed
often made on plain radiography
always taken to look for evidence of aspiration pneumonia
how are foreign bodies treated (6)
- stabilize patient
- GA
- endoscopic removal is method of choice (remove orally or pushed into stomach)
- evaluate mucosa (hemorrhage, lacerations, perforation)
- post-endoscopy radiography to look for perforation
- treat for esophagitis
what are the potential sequelae following a foreign body removal (3)
- stricture: narrowing of esophageal lumen by fibrous tissue
- fistula: abnormal tract between esophagus and usually respiratory system
- diverticulum: pouch like sacculation of esophageal wall
what is an esophageal stricture
circular band of scar tissue: secondary to severe esophagitis
what are the signs of esophageal strictures
hungry but lose weight
better with liquids
how are esophageal strictures diagnosed
difficult to see on plain radiographs
contrast radiography (number, length, location)
endoscopy (cause –> biopsy)
how are esophageal strictures treated (3)
- endoscopic balloon dilation
- followed by medical therapy for esophagitis
- +/- steroids to reduce recurrence
what are the types of hiatal hernia
congenital or acquired
what are the breeds predispositions to hiatal hernia
shar pei
english/french bull dogs
what are the two main types of hiatal hernias (2)
- sliding: distal esophagus and stomach move into mediastinum through esophageal hiatus
- perioesophageal: portion of stomach moves into mediastinum through defect adjacent to esophageal hiatus
what are the effects of hiatal hernias (3)
- gastroesophageal reflux due to decrease LES pressure
- esophagitis
- hypomotility
what are the clinical signs of hiatal hernias (7)
- congenital is seen soon after weaning
- regurgitation
- vomiting
- hypersalivation
- hematemesis
- poor body condition
- dyspnea
how are small hernias treated
medical management for esophagitis
how are large hernias treated
surgical: narrow esophageal hiatus, pexy esophagus, pexy fundus of stomach
what are the primary esophageal neoplasias (4)
- fibrosarcoma/osteosacroma (dog)
- leiomyosarcoma (dog)
- leimyoma (dog)
- squamous cell carcinoma (cat)
what are the neoplasias that can affect the esophagus (3)
- primary esophageal
- peri esophageal
- metastatic
what are the signs of esophageal neoplasia (5)
- progressive esophageal obstruction
- odynophagia
- anorexia
- weight loss
- depression
how are esophageal neoplasia diagnosed
- plain/contrast films
- esophagoscopy (biopsy/cytology)
what is the prognosis of esophageal neoplasia
often poor
what can cause parasitic granulomas
spirocerca lupi
nematode
beetle is intermediate host
what are the types of megaesophagus
what is megaesophagus
diffuse esophageal dilation and aperistalsis
what breed predispositions to congenital megaesophagus
- irish setter
- GSD
- great danes
what are secondary megaesophagus (7)
- myasthenia gravis
- severe esophagitis
- hypoadrenocorticism
- generalized myopathies
- generalized neuropathies
- toxins
- hypothyroidism
what are the clinical signs of megaesophagus (6)
- regurgitation
- dysphagia
- +/- hypersalivation
- weight loss
- +/- respiratory signs
- +/- signs of underlying disease
what can be seen on rads in megaesophagus
dilated with air, fluid or ingesta
look for signs of aspiration pneumonia
what is shown here
megaesophagus
what is shown here
megaesophagus
how is megaesophagus treated (5)
- treat underlying cause if secondary
- postural feeding
- ideal food consistency varies
- sildenafil
- treat aspiration pneumonia
how do you look for secondary causes of megaesophagus (3)
- hematology/biochemistry
- acetly choline receptor antibodies (myasthenia gravis)
- ACTH stimulation test (neuor exam –> evidence for myopathies or neuropathies)
why does metoclopramide not help dogs
acts on smooth muscle rather than skeletal muscoe and tends to close the lower sphincter
may be helpful in cats where there is more smooth muscle
how do you diagnose esophageal dysmotility
need fluoroscopy
how is esophageal dysmotility treated
same as megaesophagus
what is myasthenia gravis
end of motor nerves acetylcholine is released to stimulate the skeletal muscle via the acetylcholine receptor across the neuromuscular junction
what is the most common secondary cause of megaesophagus
myasthenia gravis
what are the types of myasthenia gravis
- congenital
- acquired
what is acquired myasthenia gravis
due to antibody production against acetly choline receptors at motor end plates
how is myasthenia gravis diagnosed (2)
- tensilon test: generalized only, non-specific
- acetyl choline receptor antibody assay: acquired only
how is myasthenia gravis treated (2)
- pyridostigmine
- consider injectable: needs to get to stomach
what is the prognosis of myasthenia gravis
esophageal function may improve with treatment
about 50% respond
what are the side effects of pyridostigmine (6)
muscarinic:
- salivation
- micturition
- bradycardia
- arrhythmias
- hypotensions
- weakness
what are causes of esophagitis (5)
- chronic vomiting
- gastroesophageal reflux (can be secondary due to GA)
- ingestion of caustic agents
- capsule retention (doxycycline)
- foreign bodies
what are the clinical signs of esophagitis (7)
- variable (asymptomatic to severe)
- dysphagia
- regurgitation
- odynophagia
- hypersalivation
- food avoidance
- weight loss
how is esophagitis diagnosed
inflammation seen endoscopically
biopsy usually necessary
likely under diagnosed
how is esophagitis treated (5)
- small low fat high protein meals
- +/- withold food PO
- sucralfate liquid
- metoclopramide
- gastric acid secretory inhibitors (PP inhibitors)
what are the causes of gastroesophageal reflux
disorder of LES allowing reflux of fluids/ingesta into esophagus
leads to esophagitis
what is gastroesophageal reflux due to (5)
- chronic vomiting
- gastric emptying disorder
- hiatal hernia
- upper airway obstruction
- anesthesia
how is gastroesophageal reflux treated (5)
- avoid high fat diets (to encourage rapid gastric emptying)
- sucralfate suspension
- gastric acid secretory inhibitors
- metoclopramide (help close the lower esophageal sphincter)
- surgery for upper airways in brachycephalic dogs helps
