Page 126 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

Chapter 9 · Surgery of the oesophagus

• Minimization of contamination The most common locations for foreign bodies include:
• Appropriate selection and application of suture • Caudal thoracic oesophagus, between the heart base
VetBooks.ir • Appropriate use of electrocautery • Cranial cervical oesophagus, just caudal to the
materials
and diaphragm
• Accurate apposition of tissues with minimal tension.
pharynx
Various closing techniques have been described and • Thoracic inlet
advocated for closure of the oesophagus, including a • Heart base.
double-layer appositional pattern, a single-layer inverting
pattern, a single-layer everting pattern, and a single-layer Bony foreign bodies are most commonly located in
appositional pattern. A single-layer appositional simple the caudal thoracic oesophagus, between the heart and
interrupted suture pattern has been successfully used in diaphragm, cranial to the diaphragmatic oesophageal
dogs and cats for oesophagotomy closure and oesopha- hiatus. Oesophageal fishhooks most commonly lodge in
geal anastomoses (Shamir et al., 1999). This pattern is the pharyngeal oesophagus and at the heart base.
generally preferred as it allows for expansion of the oesoph-
ageal lumen and minimizes disturbance of the intramural
blood supply. Clinical signs
As in the remainder of the gastrointestinal tract, the The duration of clinical signs prior to presentation varies
holding layer of the oesophagus is the submucosa considerably, ranging from a few hours to several months.
(Dallman, 1988). Regardless of the suture pattern utilized, There may be a history of ingesting bone or rubbish, or of
the submucosa must be incorporated into every bite in at roaming. Most animals present with acute clinical signs
least one layer of sutures. The optimal suture choice is a associated with complete or severe partial obstruction.
monofilament, minimally reactive, slowly absorbed suture The most classic clinical sign is regurgitation of food within
material such as polydioxanone or polyglyconate. Sutures a few minutes of eating. Water is frequently retained unless
should be spaced 2–3 mm apart to create a tight seal. there is a complete obstruction. Other clinical signs
include retching, gagging, excessive salivation, exagger-
ated swallowing, restlessness, lethargy and inappetence.
Indications for oesophageal Chronically affected animals may remain bright and alert
but show weight loss and periodic bouts of regurgitation
surgery and inappetence.
Sharp or chronic foreign bodies can result in oesopha-
Oesophageal surgery is infrequently performed in dogs geal perforation and secondary pneumomediastinum,
and cats. Indications for oesophageal surgery include: pneumothorax, mediastinitis, pleuritis, pyothorax, media-
stinal abscessation or broncho-oesophageal, tracheo-
• Foreign bodies oesophageal or aortic-oesophageal fistulae. Signs of
• Strictures
oesophageal perforation include pyrexia, depression and
• Perforation respiratory distress. Respiratory distress may also be
• Fistulae associated with aspiration pneumonia or impingement of a
• Diverticulae foreign body on the upper airways.
• Neoplasia
• Vascular ring anomalies (see Chapter 15).
Diagnosis
Oesophageal tumours are usually highly invasive and
advanced at the time of diagnosis and are therefore rarely Most oesophageal foreign bodies are radiopaque and can
amenable to surgery. Benign lesions are occasionally diag- be diagnosed with survey cervical and/or thoracic radio-
nosed. The caudal oesophagus is a site of predilection for graphy (Figure 9.1). Radiographs should also be examined
closely for signs of aspiration pneumonia, mediastinitis,
leiomyoma, a benign smooth muscle tumour, which can
often be successfully ‘shelled out’ of the oesophageal wall pneumomediastinum, pleural effusion and pneumothorax.
Radiolucent foreign bodies are infrequently encountered;
without entering the oesophageal lumen.
Vascular ring anomalies are developmental anomalies diagnosis may require a positive contrast oesophagogram,
using a sterile water-soluble low-osmolality iodinated solu-
of the great vessels that result in the encircling of the
oesophagus by a complete or incomplete ring of vessels tion. Oesophageal perforation may not be evident on
oesophagograms because the foreign body may obstruct
(see Chapter 15). Vascular ring anomalies produce partial
to near-complete oesophageal mechanical obstruction, leakage of the contrast agent from the oesophagus.
resulting in regurgitation and failure to thrive at the time of Additionally, it has been shown in humans that iodinated
weaning and transition to a solid diet. contrast material is inferior to barium for detecting smaller
perforations (Tanomkiat and Galassi, 2000). Oesopha go-
scopy can also be useful for identifying foreign bodies and
Oesophageal foreign bodies should be considered when dealing with suspicious cases
that cannot be confirmed radiographically.
Oesophageal foreign bodies are a common problem in
dogs and are occasionally diagnosed in cats. The most Treatment
common foreign bodies in dogs are ingested bones or Endoscopy
bone/cartilage composites. Young small-breed dogs,
especially terriers, are over-represented. Most affected Non-surgical retrieval of oesophageal foreign bodies is
dogs are less than 3 years of age. In cats, oesophageal usually performed under general anaesthesia with endo-
foreign bodies are more likely to be fishhooks or needles scopic guidance. This technique is associated with lower
and string foreign bodies. morbidity and mortality than surgical removal. It is the

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