Page 129 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery

sutured first. Oesophageal anastomoses can also be extends into the muscular layer of the oesophageal wall.
performed using surgical stapling instruments; however, The oesophageal injury heals by fibrosis and wound
VetBooks.ir formation, according to the human medical literature. geal obstruction. The most common cause of acquired
there may be an associated increased risk of stricture
contracture, which results in a narrow lumen and oesopha-
oesophageal stricture in dogs and cats is oesophageal
Flaps and patches: When there is an increased risk of
oesophageal dehiscence due to reduced vascularity or reflux during anaesthesia.
anastomotic tension, the oesophagotomy or oesophagec- Clinical signs
tomy incision can be reinforced with an ‘on-lay’ patch.
Tissues that have been used to patch the oesophagus Oesophageal strictures can occur in any age, breed or
include omentum, pericardium and muscle flaps. Muscle sex of dog or cat. There may be a history of general anaes-
flaps can be created from the sternothyroid muscles for thesia or oesophageal trauma, generally occurring within
the cervical oesophagus, from the intercostal muscles a month of presentation. The presenting complaint is
for the thoracic oesophagus and from the diaphragm for usually regurgitation.
the caudal thoracic oesophagus. The on-lay patch is
sutured over the oesophageal incision to provide structural Diagnosis
support, seal the incision and increase vascularity.
The presence of an oesophageal stricture can be confirmed
by positive contrast oesophagography (Figure 9.4) and
Perforations and other complications: If the oesopha-
oesophagoscopy.
gus is perforated before or during endoscopic or fluoro-
scopic retrieval of the foreign body, surgery is generally
• Oesophagography is better for determining the
indicated. Small perforations may seal on their own, number, location and length of strictures.
particularly if oral intake of food and water is prohibited
• Oesophagoscopy allows direct assessment of the
for 72 hours. Cervical perforations may only require local stricture and the mucosal lining of the oesophagus,
drainage because of support from local soft tissues.
and treatment by bougienage or balloon dilation. The
Thoracic perforations are more likely to result in life- narrowed oesophageal lumen may prevent passage of
threatening consequences, and should be operated upon
the endoscope through the stricture, therefore it may
if peri-oesophageal leakage is present. Samples for not be possible to evaluate endoscopically the number
culture and sensitivity testing should be obtained and
and length of strictures in certain cases.
thoracostomy tubes placed intraoperatively in the case
of thoracic oesophageal perforation.
Oesophageal perforation can result in mediastinal Treatment
abscess formation or pyothorax, which should be drained Dilation
and flushed at the time of surgery. Oesophageal foreign
bodies occasionally result in the formation of a second- The preferred treatment for oesophageal strictures is
ary oesophageal fistula. Fistulae most commonly form bougienage or balloon dilation.
between the oesophagus and a bronchus, but can occa- • Bougienage uses conical dilators of increasing
sionally communicate with the trachea, lung parenchyma, diameter to push open the stricture.
aorta or skin. Oesophageal fistulae require surgical • Balloon dilation (Figure 9.5) involves insertion of a
management. Anaesthesia is a particular challenge as balloon catheter through the stricture and inflation of
the fistula makes ventilation difficult and inhalant anaes- the catheter.
thetics will escape into the oesophagus. The fistulous
tract should be excised rather than ligated.
Both techniques can be performed with endoscopic or
fluoroscopic guidance. Balloon dilation has the theoretical
Prognosis advantage of exerting a stationary radial stretch force,
The prognosis after foreign body removal is generally
excellent, except in cases of thoracic oesophageal per -
f oration (see above). Complications of oesophageal foreign
body removal include oesophagitis, ischaemic necrosis,
dehiscence, leakage, infection, and fistula, diverticula or
stricture formation. Perforation of the aorta or pulmonary
artery by the foreign body before or during retrieval is fatal.
In one study, 10 of 66 dogs (15.2%) that underwent
oesophagoscopy for foreign body retrieval experienced
complications, with perforation being the most common.
Of these 10 dogs, six died or were euthanased as a result
of these complications. Bone foreign bodies and a body-
weight of <10 kg were found to be significant risk factors
for complications (Gianella et al., 2009).

Oesophageal stricture
9.4 Oesophageal stricture. Lateral thoracic radiograph of a 6-year-
old mixed breed dog that had started regurgitating 1 week
Oesophageal strictures can be either congenital or after ovariohysterectomy. The radiograph was obtained 30 minutes
acquired. Congenital strictures are rare in dogs and cats. after administration of a barium meal and demonstrates a caudal
Acquired oesophageal strictures are uncommon, and result oesophageal stricture.
from severe circumferential injury to the oeso phagus that (Courtesy of the Veterinary Imaging Database, University of California, Davis)

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