12) diseases of oesophagus regurgitation vs vomitus

Question 1

regurgitation general

Answer 1

Expulsion of material from the mouth,
pharynx or oesophagus
• Spontaneous
• Passive backflow
• Undigested food, no bile
• Eating the regurgitated content (no nausea)

Question 2

regurgitation mechanism

Answer 2

• Altered motility
• Obstruction of flow
o External compression
o Internal obstruction
• inflammation

Question 3

vomitus general

Answer 3

Expulsion of material from the stomach and / or intestines
• Active muscle contractions, retching
• Undigested or digested food, gastric chyme, bile
• Nausea

Question 4

vomitus mechanism

Answer 4

• Activation of peripheral receptors within the gastrointestinal tract
• Activation of central vomit centre by CNS disease e.g. Motion sickness, neoplasia etc
• Vestibular disease
• Activation of chemoreceptor trigger zone by chemicals / toxins, e.g. uraemia, diabetic ketoacidosis

Question 5

Distinguishing regurgitation from vomiting

Answer 5

• History
  • Nausea, retching, eating the content, bile, stretching or flexing the neck during swallowing, aspiration of water / liquid and coughing
• Physical examination
  • Palpation of distended cervical oesophagus, cervical mass, injury or foreign body
• Thoracic radiography
  • Obvious megaoesophagus, foreign body, perforation and pleuritis or PTX
• Endoscopy: oesophagitis, hiatal hernia, stricture
• Fluoroscopy: motility disorders, hiatal hernia, stricture

Question 6

oesophagus - history and clinical signs

Answer 6

• Regurgitation
• Dysphagia
• Odynophagia (painful swallowing)
• Salivation
• Changes in appetite
  • ↑ motility disorder
  • ↓ inflammatory disorder
• Aspiration pneumonia
  • Coughing, fever, dyspnoea, pulmonary crackles
• Cachexia, weight loss

Question 7

diagnostic evaluation of esophagus

Answer 7

• Physical evaluation
  • Expanded oesophagus, pneumonia, neurological deficits (mydriasis), salivary gland, foreign body, mediastinal tumour
• Laboratory examination
  • WBC (pneumonia, perforation, pleuritis)
  • Na+/K+ (hypoadrenocorticism → megaoesophagus)
  • CK, AST (polymyositis → megaoesophagus)
  • Acetylcoline receptor antibody (25% of acquired megaoesophagus: myasthenia gravis!)
  • Coprology (spirocercosis)
• Radiography
  • Foreign body, PRAA, megaoesophagus
• Endoscopy, fluoroscopy

Question 8

oesophageal diseases - oesophagitis

Answer 8

• Causes
  • GOR, anaesthesia, persistent vomiting, foreign body, doxycycline (cats), motility disorder, megaoesophagus, caustic substances
• Symptoms
  • Odynophagia, regurgitation, salivation, food refusal, coughing, fever, dyspnoea
• Diagnosis
  • Clinical signs
  • WBC ↑
  • Endoscopy
  • Radiography?
• Treatment
  • Omeprazole + prokinetics (see GOR treatment)
  • Sucralfate suspension
  • Total parenteral nutrition / enteral nutrition (in severe cases)
  • Aspiration pneumonia: antibiotics
• Prognosis usually good
  • Untreated: stricture, megaoesophagus (cause or consequence?)

Question 9

gastro-esophageal reflux

Answer 9

• Poor closure of cardia → HCl, pepsin, trypsin, bile, HCO3- → inflammation; frequent problem!
• Aetiology
  • Delayed gastric emptying
  • Upper airway obstruction
  • Hiatal hernia
  • Anaesthesia
  • Chronic vomiting
• Symptoms
  • Same as for oesophagitis
  • Reverse sneezing
  • Chronic bronchitis, laryngitis, rhinitis
  • Eructation
• Diagnosis
  • Symptoms + history
  • Endoscopy! (oesophagitis, hiatal hernia)
• Treatment
  • Low fat diet, avoiding late night feeding
  • H2-receptor blockers/proton-pump inhibitors
  • Prokinetics: cisapride, tegaserod (serotonin-4-receptor agonists)
  • Sucralfate
  • Enhance cardia closure
  ➢ Metoclopramide
  ➢ Erythromycin
  ➢ GABA “B” type agonist: baclofen
  • Brachycephaly syndrome → surgery
• Prognosis usually good

Question 10

Oesophageal foreign body

Answer 10

- Symptoms
• Regurgitation
• Salivation
• Distended abdomen
• Coughing, fever, dyspnoea
- Diagnosis
• Symptoms
• WBC ↑
• Thoracic radiography (survey and contrast) or
• Endoscopy
- Treatment
• Endoscopic removal
➢ Informing the owner (risk of procedure: perforation, PTX, surgery)
➢ Prepared operation room
➢ Anaesthesiologic preparedness
• Unsuccessful attempt (30 – 70%)
➢ Surgery
➢ Gastric tubing
➢ Euthanasia

Question 11

oesophageal motility disorders

Answer 11

• Dysmotility / oesophageal weakness
  • Motility disorder + food retention + regurgitation
  • Aetiology: idiopathic, muscle atrophy, myasthenia gravis, autoimmune disorders, post-anaesthetic condition (reversible), oesophagitis
  • Types
  ➢ Megaoesophagus
  o Severe dysmotility + oesophageal expansion
  ➢ Partial oesophageal dysmotility
  ➢ Dysautonomia
  ➢ Diverticulum
  • Clinical manifestation
  ➢ Dysphagia / regurgitation
  ➢ Dysphagia / regurgitation + bronchopneumonia
  ➢ Bronchitis / bronchopneumonia → dysmotility
  • Symptoms
  ➢ Regurgitation, salivation, coughing, fever, dyspnoea, weight loss
  • Diagnosis
  ➢ Fluoroscopy
  ➢ Radiography (survey, contrast

Question 12

Megaoesophagus

Answer 12

• Common in dogs, rare in cats
• Persistent reduced motility of the oesophagus
• Laryngeal paralysis can lead to megaoesophagus
• Must assess for aspiration pneumonia
• Congenital (cause is unknown)
  • Miniature Schnauzers, Great Danes, Dalmatians, Shar-Pei, Irish Setter, Labrador Retriever
  • Clinical signs usually develop when weaning onto solid food
  • No treatment
  • Poor prognosis
• Acquired (adult onset)
  • Primary
  ➢ Idiopathic
  ➢ Diagnosis of exclusion (i.e. causes of secondary)
  ➢ Typically, large breed dogs
  ➢ Treatment
  o Special feeding
  ▪ “Bailey chair” – keeping the patient vertical while feeding
  o Bethanechol + Sucralfate
  • Secondary
  ➢ Myasthenia gravis (20% of cases)
  o Immune response against acetylcholine receptors
  o +/- can be focal or generalized (systemic weakness)
  o Treatment: pyridostigmine
  ➢ Other
  o Hypoadrenocorticism (prednisolone), lead poisoning (Ca-EDTA), oesophagitis, hypothyroidism (levothyroxine), systemic lupus erythematosus (prednisolone), polymyositis/polymyopathy (see SLE)

Question 13

Spirocercosis

Answer 13

- Spirocercosis lupi
• Widely distributed nematode, causing parasitic nodules in the oesophagus, aortic aneurysms, spondylitis
- Symptoms
• Regurgitation, vomiting, weight loss, coughing, dyspnoea, rarely sudden death
- Diagnosis
• Faecal examination
• Endoscopy
- Treatment
• Doramectin
➢ Off-label
➢ MDR1 gene mutation!
• Imidacloprid/moxidectin
• Surgery
- Prevention
• Parasitic prevention with milbemycin

Question 14

Persistent right aortic arch

Answer 14

• Congenital disease
• Extraluminal compression by the ligamentum arteriosum
• Symptoms
  • Shortly after the animal eats solid food for the first time
  • Regurgitation, coughing, dyspnoea, weight loss
  • Rarely minor signs, patients are several years old
• Diagnosis
  • Survey and contrast radiography
  ➢ Ventral and leftward tracheal deviation, cranial oesophageal dilatation
  • Endoscopy
• Treatment
  • Surgery