Ch 90 Oesophagus Flashcards
What nerves pass through the oesophageal hiatus with the oesophagus?
The dorsal and ventral vagal trunks
What msucle does the muscularis layer originate from?
How does the muscularis differ in dogs and cats?
Muscularis origniates from the cricopharyngeus muscle and cricoesophageal tendon
In dogs, the oesophagus is 100% striated muscle.
In cats, it chages to smooth muscle in the distal oesophagus
anatomy
- cervical: dorsal to cricoid cartilage, then left of the trachea towards thoracic inlet
- thoracic: initially left of the trachea, becomes dorsal at the tracheal bifurcation towards the esophageal hiatus
- aorta obliquely crosses the left side of the midthoracic esophagus.
- Vagus nerves: sides of oesophagus in caudal thorax
- At its cranial and caudal ends, the esophagus has functional sphincters (no truely anatomical)
Layers of the Esophageal Wall
- outer layer: the adventitia
- muscularis: striated muscle (smooth caudal third cats)
- submucosa: contains blood vessels, nerves, and simple mucous glands
- mucosa: stratified squamous epithelium
Esophageal Blood Supply and Innervation
- cervical esophagus: branches of the cranial and caudal thyroid arteries.
- thoracic cranial two-thirds: The bronchoesophageal artery
- caudal thoracic: branches of the aorta or dorsal intercostal arteries.
- esophageal arteries and veins form a rich, intramural plexus of anastomosing vessels in the submucosal layer
- nerves: vagus
List the three phases of swallowing
Oropharyngeal (oral, pharyngeal, cricopharyngeal; trigeminal (V), facial (VII), glossopharyngeal (IX), vagus (X), and hypoglossal (XII) nerves)
Oesophageal (peristalitic)
Gastroesophageal
What structures function as the cranial and caudal oesophageal sphincter?
Cranial
- Thyropharyngeus muscle
- Cricopharyngeus muscle
Caudal
- Increase in thickened of circumferential striated muscle (dog)
- Diaphragmatic crural muscles
- Angle at which the oesophagus and stomach meet
- Folds of gastrooesophageal mucosa
List the three braod categories of oesophageal dysphagia
MIFfy
Mechanical (or anatomical)
- foreign bodies,
- strictures,
- tumors,
- vascular ring anomalies,
- hiatal hernias
- gastroesophageal intussusceptions
Functional (or neuromuscular)
- idiopathic megaesophagus
- myasthenia gravis
- GOLPP
Inflammatory (oesophagitis)
- GERD
- ingestion of corrosive substances
List 4 reasons why the oesophagus has a higher prevalence of incisional dehiscense
Lack of serosa
Segmental blood supply
Lack of omentum
Constant motion
What are the recommendations for feeding after oesophageal surgery?
NPO after surgery for 1-7 days. Consider placement of gastrostomy or enterostomy tube
What is the surgical approach to the cervical oesophagus?
Ventral midline
- separating the paired sternohyoid muscles and retracting the trachea to the right
- avoid damage to the recurrent laryngeal nerve
What are the option for surgical approach to the cranial thoracic oesophagus?
Extension of midline cervical approach into cranial median sternotomy
Left 3rd or 4th intercostal thoracotomy with ventral retraction of the brachiocephalic trunk and subclavian vessels
Right 3rd, 4th or 5th intercostal thoracotomy with ventral retraction of the trachea
What is the recommended approach for the caudal thoracic oesophagus
Left sided 7th, 8th or 9th intercostal thoracotomy to avoid the caudal vena cava
What are the options for surgical approach to the caudal oesophagus and stomach?
Combined laparotomy and diaphragmatic incision
Caudal median sternotomy
What are the recommended suture material for the oesophagus?
Polydioxanone or polyglyconate
- interrupted pattern (for anastomoses to permit esophageal dilatation)
- continuous for oesophagotomy
closure pattern
- submucosa the functional suture-holding layer
- studies both support single and double layer closure (mucosa/submucos + muscle)
- STUDY: simple continuous single-layer pattern had the least wound strength and poorest tissue apposition > reocmmended signle interrupted or double
2 mm from the cut edge and 2 to 3 mm apart
What is the recommended closure of a oesophagotomy?
1- or 2-layer interrupted or continuous pattern with bites 2mm from cut edge and 2-3mm apart
Esophagotomy
- Indications: FB, perforations and diverticula
esophagus is suctioned transorally to reduce contamination. - sutures and suction can be used to minimize spillage
- incision is extended longitudinally
- 2 layer closure; knots into the lumen
- integrity of the closure can be tested by distending the esophagus with saline
- incisions can be reinforced with various materials
- not receive food or water by mouth for at least 24 to 48 hours after surgery
oesophageal Resection and Anastomosis
- Indications: congenital obstructions, strictures, injury, diverticula and neoplasia
- extent of the proposed resection should be estimated before Sx by scope, contrast esophagography, MRI or (CT)
- Esophageal substitution techniques should be considered if excessive resection needed
- Circumferential partial myotomy may reduce anastomotic tension (fluu-thvkness myotomy disrupt submucosal vascular plexus and subsequent ischemia)
- lumen can be occluded with fingers, umbilical tape, or noncrushing clamps
- surgical stapling instruments or using a biofragmentable anastomosis ring (no significant difference in the complication rate or healing with either method)
How much of the oesophagus can be removed? Experimentally and clinically
Experimentally: 20% of the cervical oesophagus and 50% of the thoracic oesophagus
Clinically however, resection of more than 3-5cm is associated with an increased risk of dehiscense
What is the purpose of a circumferential partial myotomy in an oesophageal resection and anastomosis?
A tension relieving technique for closure
What is recommended in terms of feeding after oesophageal resection and anastomosis?
Fluid and nutritional requirements are provided for at least 1 week through a gastrostomy or enterostomy tube.
List some materials which can be used for oesophageal patching
Omentum
Pericardium
Local muscle flaps (longus colli, sternothyroideus, intercostal, diaphragmatic)
Stomach or intestine
Porcine SI submucosa
Lyophilised dura mater
Expanded polytetrafluoroethylene patched
Esophageal Patching
- reinforce existing esophagus (“on-lay” patch)
- partial circumferential replacement of the esophageal wall (“in-lay” patch) i.e. for longitudinal division of an esophageal stricture
- esophageal stricture formation may be minimized using patching (shown for omentum and muscle)
omental flap
- caudal oesophagus
- right gastroepiploic artery and its branches to the omentum are ligated, brought through diaphragm
muscle
- Pedicle grafts can be created from local muscle
- cervical: longus colli, sternothyroideus,
- thoracic: intercostal, diaphragmatic (caudal)
List some options for oesophageal substitution
Inverse tubes skin graft
Omocervical cutaneous island axial pattern flap
Tubed intercostal musculopleural pedicle graft
Diaphragmatic pedicle graft
Tubed latissimus dorsi musculocutaneous flap
Gastric advancement and oesophagogastric anastomosis
Gastric tubes created from the greater curvature
Free microvascular grafts of the intestine (unsuccessful experimentally)
Esophageal Substitution
- clinical experience with esophageal replacement in small animals is minimal
inverse tubed skin graft (cervical)
- Staged: A cranially based single pedicle skin flap is formed into an inverse tube, Two weeks later the cranial skin pedicle is cut and anastomosed cranially to the remaining end of the esophagus.
- Alternatively, the proximal and distal ends of esophagus form two esophagocutaneous fistulas
- complications: luminal obstruction with hair, lack of peristalsis, and indistensibility
Muscle grafts
-Omocervical cutaneous island axial pattern flap
- Tubed intercostal musculopleural pedicle graft
- Diaphragmatic pedicle graft
- Tubed latissimus dorsi musculocutaneous flap
gastric advancement and esophagogastric anastomosis (caudal thoracic)
- complications: leakage, stricture, chronic vomiting, reflux esophagitis, gastric dilatation, herniation of viscera thru diaphgragm
- tubes from greater curvature
- splenectomy required
- portion of the gastric tube maintained within the abdomen to reduce reflux
Vascular Ring Anomalies
- developmental anomalies of the great vessels that result in complete or partial encircling of oesophagus and trachea
- abnormalities of the third, fourth, or sixth aortic arches result in 1 or 2 vessels coursing around the esophagus and trachea.
In embryos
- great vessels derived from the paired dorsal and ventral aortas and the six interconnecting pairs of aortic arches
- The vascular system forms around the embryonic foregut and pulmonary bud, selective involution and reconnection result in the formation of the definitive cardiovascular system and release of the esophagus and trachea.
normal embryologic development
ventral aortas fuse → heart
caudal dorsal aortas fuse > descending aorta
1st and 2nd aortic arches
- involute early
- ventral origins → external carotid arteries
- dorsal origins → internal carotid arteries
3rd and 4th
- ventral aortas between > common carotid
- dorsal aortas involute
- left 4th aortic arch + dorsal root → adult aortic arch
- right 4th aortic arch → right subclavian
- right ventral root of 4th → brachiocephalic trunk
5th aortic arches
- involute
6th aortic arches
- pulmonary arteries
- the left pulmonary artery retains a connection to the aorta—the (left) ductus arteriosus—ligamentum arteriosum after birth
- The right ductus arteriosus and section between 6th arch and dorsal aortas involute to release the esophagus and trachea
- left 7th intersegmental artery → left subclavian
normal = left aorta
Which of the 6 primordial embryonic arches are retained as adult structures? What structures do they form?
Arches 3, 4 and 6
- Left 4th forms the aorta
- 6th form the pulmonary arteries,
- 3rd forms the common carotid arteries.
Dorsal aorta fuses to form descending aorta caudally and cranially forms the internal carotid arteries.
Ventral aorta fuses to form the heart caudally and cranially forms the external carotid arteries
Types of vascular ring anomalies (I-VI)
I - persistent right aortic arch (4th) with left ligamentum arteriosum
II - persistent right aortic arch with aberrant left subclavian
III - persistent right aortic arch, aberrant left subclavian and connecting ligamentum
arteriosum
IV - double aortic arch
V - persistent right DA/LA (normal left 4th, persistent right 6th)
VI - aberrant right subclavian
most common= PRAA + left LA
additional types reported
- left intercostal arteries
- left vessel ajoining aorta to right subvlavian
- right aortic arch with left-sided brachiocephalic trunk (14%)
cats (4)
- PRAA with left LA
- persistent right ligamentum arteriosum with a left aortic arch,
- PRAA with right LA and aberrant left subclavian artery
- double aortic arch
Type I: Persistent right aortic arch with a left ligamentum arteriosum
- most common
- aortic arch develops from right fourth aortic arch.
- Persistent right aortic arch and right ductus arteriosum would be the mirror image of the normal anatomy and would not result in a vascular ring.
- causes oesophageal constriction
Type II: Persistent right aortic arch with an aberrant left subclavian artery
- left subclavian artery passes dorsal to the esophagus from the right-sided aorta, resulting in an incomplete vascular ring.
- casues oesophageal constriction
- right ligamentum arteriosum (only subclavian stricture)
Type 3: persistent right aortic arch, left ligamentum arteriosum, and aberrant subclavian artery
- resulting in
two distinct sites of oesophageal compression
type IV: Double aortic arch
- persistence of both left and right fourth aortic arches
- produce significant tracheal stenosis
Type V: Persistent right ligamentum arteriosum with normal (left) aortic arch
- mirror image PRAA : aortic arch develops normally on the left, but the right sixth arch persists as the ductus arteriosus
- uncommon
- causes oesophageal constriction
- cannot be corrected via a left lateral thoracotomy
type VI: Aberrant right subclavian artery with normal (left) aortic arch
- right subclavian artery passes dorsal to the esophagus, resulting in an incomplete vascular ring
- oesophageal constriction
- Persistent left cranial vena cava with a nonelastic band around the esophagus has been reported.
What percentage of dogs with a vascular ring anomaly will also have a persistent left cranial vena cava?
Up to 45% - Can complicate the surgical approach
What percentage of dogs with a PRAA with also have a PDA?
up to 10%
Congenital anomalies of the great vessels
- most variants are not clinically significant.
- most common (incidence 6%; 8 of 136 dogs) = aberrant right subclavian artery; not result in clinical signs.
- PRAA + various anomalies > 95% of clinical cases
- familial and breed tendencies, affected individuals should be neutered
What breeds are predisposed to vascular ring anomalies?
German Shepherds and Irish Setters
Persians and Siamese cats
diagnosis
CS
- 92% of dogs reported >15kg
- usually considered normal until weaning, with clinical signs of postprandial regurgitation
- Affected animals may grow more slowly
- Coughing and respiratory distress
Radiographs
- esophagus cranial to the heart may be dilated with air, fluid, or ingesta.
- On VD > might identify the descending aorta on the right side
- Tracheal deviation on VD +/- tracheal narrowing
- positive-contrast radiography: dilatation and obstruction over the base confirmed with using barium.
Fluoroscopy
- document abnormal esophageal peristaltic activity.
Esophagoscopy
- ruling out other causes of compression and can simultaneously reveal mucosal lesions.
- heart beat on the right side of the esophagus
Rads, fluoro and scope reveal little about the type of vascular ring that is responsible
CT angiogram
- variety of vascular derangements known to occur > advanced diagnostic imaging is necessary to identify the specifics
- Numerous case reports in the recent literature support the usefulness of CT
- +/- Echocardiogram
- +/- MRI (gold standard in humans)
Preoperative
- elevated feeding of a slurry diet (often malnourished)
- severely debilitated animals > tube feeding
- aspiration pneumonia > antibiotics and management b4 surgery
Surgery planning
- Type 3 + Type 7 > potential for 2 sites of constriction
- Type 3 (PRAA + LA + LS) and 4 (Double AA) vascular ring anomalies may require different surgical approaches
medical mgmt usually unrewarding because dilatation increases with age
surgery
- Early surgical correction is advisable to prevent progressive dilation of the cranial portion of the esophagus and chronic esophageal changes + reduce risk of aspiration pneumonia
- aim = divide the compressive structure and transect periesophageal fibrous bands that form under it.
- Most VRA > left lateral thoracotomy.
- Persistent right LA with a left aortic arch + aberrant R subclavian >right lateral thoracotomy.
- If the type not known, left lateral thoracotomy should be chosen
What is the surgical approach for a PRAA?
Left 4th IC thoracotomy in dogs (5th may be preferred in cat)
What nerve loops around the caudal aspect of the ligamentum arteriosum?
Left recurrent laryngeal nerve
Sx: PRAA with a left ligamentum arteriosum
- A left persistent cranial vena cava, if present, can be retracted.
- If a prominent hemiazygos vein is also present> should be ligated
- The mediastinum is incised longitudinally >preserve vagus nerve + the left recurrent laryngeal nerve
- The ligamentum arteriosum is carefully dissected, double ligated with silk suture and transected
- A stiff tube or balloon catheter is then inserted through the mouth > any remaining constricting fibrous bands are transected
- thorocostomy tube
Thorascopic treatment of PRAA
Nucci 2018: thoracoscopy versus thoracotomy
- Retrospective > 30 dogs, 10 scopy vs 20 thoracotomy, 5 converted from scope to open, not associated with higher morbidity or mortality rates, compared with thoracotomy, reduced hospitalisation
- Simultaneously performed esophagoscopy can provide transesopha¬geal illumination for guiding surgical dissection of vascular ring anomalies during thoracoscopy
- Cons: technically challenging, haemorrage
Sx: Double aortic arch
- the dominant arch is first determined by angiography or echocardiography.
- The vessel that provides the stronger femoral pulse when occluded is the vessel to be resected intra-op
- Through an ipsilateral thoracotomy, the atretic arch is identified, divided between vascular clamps, and oversewn.
- Ligation of 1 aortic arch may reduce the functional volume of the aorta > increase in left ventricular afterload, pulmonary hypertension, cardiac insufficiency, and death.
Post-op
- tailored to the needs of the individual patient.
- slurry-type diets are fed from an elevated position starting 12 to 24 hours after recovery.
- minimal regurgitation is observed, the amount of water added to the slurry is gradually reduced over 2 to 4 weeks
- In some, long-term elevated feeding is necessary
Prognosis
- lifelong risk of aspiration pneumonia if regurgitation fails to resolve
- abnormal esophageal function dt loss of neuromuscular function and resultant lack of aboral peristalsis.
- recommended surgery as soon as possible (reduce dilatation + secondary atony), no evidence young age have a better long-term prognosis.
- Some operated late in life have an excellent outcome
potential factors associated with persistent regurgitation
- degree of esophageal constriction and dilatation,
- megaoesphagus,
- severity of debilitation,
- aspiration pneumonia before correction
- most prognosis focused on PRRA + LA anomalies specifically.
long-term outcome
- varies depending on the retrospective study
- 52 dogs: 92% surviving, excellent (normal) in 30%, good (dietary modification and/or minimal regurgitation) in 57%, and poor 13%
- 47 dogs, survival 94% outcome excellent in 92% and good in 8%
- Persistent megaesophagus 13 dogs, 12 of had excellent outcomes
outcome
- clients advised that many dogs may continue to regurgitate and will need continued dietary medical management after surgery
- some dogs to respond poorly, despite surgical correction.
- With postoperative support, > 70% have significant improvement in QOL
What breeds are predisposed to congenital generalised megaoesophagus?
What is the prognosis?
Treatment option?
Irish setters, Great Danes, GSD, Labs, Shar-Peis, Newfoundlands, Min Schnauzers and Fox Terriers
Prognosis is poor with 74% mortality rate at 1yo
Treatment option: Oesophagodiaphragmatic cardioplasty using Torres technique (good outcome in 3, excellent 1, unsuccessful 2)
Esophageal Foreign Bodies
- most common in dogs are ingested bones.
- ## In cats, fishhooks, needles, and string
where do Esophageal foreign bodies most commonly lodge? (3)
- thoracic inlet
- heart base
- caudal esophagus (55% to 79%)
Clinical Signs
- Small-breed dogs, particularly terrier breeds
- often younger than 3 years
- few hours to several months
- classic: regurgitation of food
- retching, gagging, excessive salivation, restlessness, lethargy, inappetence.
- Chronic: weight loss and periodic bouts of regurgitation and inappetence
- esophageal perforation, pneumomediastinum, pneumothorax, pyothorax, mediastinal abscessation (can present very unwell)
diagnosis
RADS
- 99% of bone foreign bodies were seen
- increased soft tissue density in 53%
- dilated air-filled cranial esophagus in 21%
- look for aspiration pneumonia, mediastinitis, pneumomediastinum, pleural effusion, pneumothorax, and tracheal compression
- Positive-contrast esophagography
Esophagoscopy
- identifying foreign bodies
- removal
- evaluating esophageal health/perforation
Oxygen saturation, blood pressure, and ventilation should be monitored during esophagoscopy due to risk of?
tension pneumothorax can occur during insufflation if a perforation is present
tension pneumothorax
air builds up in the pleural space, putting pressure on the heart and lungs
treatment - scope
- initial attempt with endoscopy or fluoroscopy using grasping forceps
- balloon catheter for relatively smooth foreign bodies
- not be forced because this may induce or enlarge a perforation (cf tension pneumo)
- cannot be extracted > advance it into the stomach.
- Bones will be digested in the stomach and do not require a gastrotomy
- oesophagus should be inspected; surgical exploration should be performed if a significant esophageal perforation or fistula is present.
STUDY: 90 dogs, FB extracted endoscopically in 63%, pushed into stomach 29%; only 8% required surgical management
perforation
- determine the size of the hole and the health of adjacent esophageal tissue.
- Small perforations may seal on their own
- Thoracic perforations are more likely to result in life-threatening consequences,
- oesophagram can be performed after FB removal to evaluate for leakage
When is surgery recommended for oesophageal perforation?
If contrast material migrates away from focal area of perforation, pleural effusion, pneumothorax, pneumomediastinum or sepsis
If small performation with healthy adjacent tissue, may heal on its own if oral intake of food and water are prohibited for 72hr
surgical removal of FB
when extraction risk for laceration of esophagus or major vessels
FB between heart and diaphragm
- removed via a gastrotomy performed through a midline laparotomy or through a diaphragmatic incision
Esophagotomy or partial esophagectomy
- when FB cannot be removed by other means
- Esophageal perforations should be debrided and closed and supported with a local flap of muscle or omentum
post-op
- observed carefully for 2 to 3 days for signs of esophageal leakage
- H2 receptor blocker (e.g., ranitidine or famotidine) or proton pump inhibitor (e.g., omeprazole)
- no food until 24-48hr
- perforation/surgery > no food 3-7 days (gastrostomy tube)
What is the prognosis for oesophageal foreign bodies?
Excellent except in cases of thoracic perforation (mortality rate 43% compared to 7%)
complications fo FB removal
- hemorrhage,
- esophagitis,
- aspiration pneumonia,
- ischemic necrosis,
- rupture,
- dehiscence, leakage,
- infection,
- fistulas
- stricture
- Perforation aorta or pulmonary arteries
penetrating oesophageal injury
- penetrating stick injury in dogs
- generally occur in the cervical esophagus
- bite wounds
dx
- cervical emphysema. Thoracic radiographs should be evaluated for pneumomediastinum, pneumothorax, pleural effusion,
- scope
tx
- early examination and treatment under anesthesia is recommended
- Extensive trauma, necrosis, and abscesses may require open wound management
- gastrostomy tube for enteral nutrition and avoiding oral food
What is the prognosis of acute penetrating oesophageal injuries?
Mortality of dogs with acute penetrating stick injuries 36%
In one study of dogs with bite wounds to the neck, all patients with oesophageal perforation died…
Paraesophageal Abscess
Oesophageal Stricture
- Acquired: from severe, circumferential esophageal injury extending into the muscular layer
- heals by fibrosis and wound contracture > narrowed lumen and esophageal obstruction.
- most common cause = oesophageal reflux during anesthesia
- other causes: chronic vomiting, ingestion of a corrosive substance, thermal burns, radiation injury, and foreign bodies
- oral doxycycline in cats
- Postanesthetic esophageal strictures can occur at any level, single (62%) or multiple (38%)
Dx
- based on positive-contrast esophagography and esophagoscopy
What is the preferred method of treatment of oesophageal strictures?
Bougienage or balloon dilation with most requiring multiple dilations with good outcome in 71-88% of cases (High incidence of re-stricture and dehiscense after surgical resection)
stricture Tx
dilation
- Bougienage: conical dilators of increasing diameter to push open the stricture.
- Balloon: inflating a balloon catheter within the stricture
- balloon dilatation exert a stationary, radial stretch force, where as bougienage exerts longitudinal shearing forces > risk esophageal perforation
- Esophageal perforation is reported in 3.6-11% after balloon dilatation
medical
- mitomycin C or triamcinolone
stent
- short term imporemeny
- stent migration, discomfort, and tracheoesophageal fistula formation
What are the surgical treatment options for oesophageal stricture? (4)
- Simple oesophagoplasty (ransverse closure of a longitudinal incision)
- resection and anastomosis (rarely performed as strictures too large)
- Patch oesophagoplasty (ternothyroideus, intercostal, diaphragmatic or pericardial in-lay)
- oesophageal substitution
prognosis strictures
- Most improved with repeated dilatation treatments;
- may continue to regurgitate periodically.
- The major complications of stricture dilatation are perforation and recurrence
- A good outcome is reported in 71% to 88%
- Surgical: high incidence of stricture recurrence and incisional dehiscence.
Esophageal Diverticula
- in dogs only esophageal diverticula arising between the heart base and diaphragm (epiphrenic diverticula) have been well described.
- single or multiple
- associated bronchoesophageal fistula.
- diverticulum can become impacted with ingesta, distorting and obstructing the esophageal lumen
- can lead stricture, fistulas or adhesions to adjacent lung or rupture.
CS
- regurgitation, retching, gagging, gulping, generalized pain, hypersalivation, weight loss, and anorexia
Dx
- Positive-contrast esophagography
- fistulas results in consolidation of one caudal lung lobe
- Esophagoscopy
- CT
List the 2 forms of oesophageal diverticula and define each
in humans
Pulsion diverticulum - An outpouching of mucosa that herniates through a defect in the tunica muscularis
Traction diverticulum - A full thickness deviation of the oesophageal wall. Usually caused by inflammation in an adjacent organ causing adhesion formation
What breeds are over represented for oesophageal diverticula
Cairn terriers, Min Poodles, Parson Russell Terriers
What is the surgical treatment for an oesophageal diverticula?
What is the prognosis?
Small diverticula may be managed conservatively (gruel-type diet, upright feeding position)
Large diverticula require surgical resection (diverticulectomy, partial resection and oesophageal in-lay patch, complete resection and anastomosis, oesophageal substitution)
Peridiverticular adhesion or a bronchoesophageal fistula may require a concurrent lung lobectomy
Prognosis is good if amenable to simple resection. Guarded for those which require extensive surgery or those with concurrent fistula
Which bronchus is most commonly effected by a bronchoesophageal fistula in dogs?
Right caudal lung lobe bronchus
oesophageal Fistulas
- abnormal communication between the esophagus and the trachea, bronchus, lung parenchyma, or (less commonly) the skin
- congenital or acquired.
- Congenital = incomplete separation of the tracheobronchial tree from the digestive tract
- acquired = secondary to esophageal foreign bodies
- most common clinical sign is coughing,
- thoracic radiographs, an alveolar, bronchial, or interstitial lung pattern in the affected lobe is seen
- dx with posiive-contrast eosophagram (scope may fail to dx) or CT
Sx
- TIVA anaesthesai recommended
- fistulous tract should be excised rather than ligated.
- oesophageal defect can usually be closed primarily
- lung lobectomy
- antibiovics for infection
What is cricopharyngeal dysphagia?
What breeds are predisposed?
A swallowing disorder characterised by cricopharyngeal achalasia (upper oesophageal sphincter fails to open during the cricopharyngeal phase of swallowing) or asynchrony (incoordination between the contraction of the pharyngeal contractor muscles and relaxation of the upper oesophageal sphincter)
Golden Retriever and Cocker Spaniels
What is the recommended treatment for cricopharyngeal dysphagia?
Prognosis?
Cricopharyngeal myotomy/myectomy - 2-2.5cm of cricopharyngeal muscle is removed from dorsal midine
Sometimes combine with partial or complete thyropharyngeal myotomy
Prognosis is excellent!
Dysphagia ddx
abnormal prehension:
- jaw dz
- oral mass
abnormal gag reflex (pharyngeal)
- myasthenai gravis
- toxoplasma
- polyneuropathy
- brainstem dz
- neuromascular junction dx (tick, botulism)
prehension and gag normal
- cricopharyngeal dysphagia
What are the most common forms of oesophageal neoplasia in dogs?
SCC
leiomyosarcoma
OSA
FSA
undifferentiated sarcoma
What nematode is often associated with oesophageal neoplasia in the dog?
Spirocerca Lupi - associated with OSA, FSA and undifferentiated sarcomas.
Dogs are the definitive host and become infested by ingesting the intermediate host, a coprophagous beetle
Hypertrophic osteopathy was reported in 38.7% of malignant spirocerca infestations and no benign cases
What is the prognosis for dogs and cats with oesophageal neoplasia?
Very poor… often extensive involvement of oesophagus at time of diagnosis and may who undergo resection and anastomosis do not survive to discharge
Complications following removal of oesophageal foreign bodies: a
retrospective review of 349 cases
Wyatt and Barron 2019
AVJ
complications: at time of removal 20/349 (5.9%) - 14/20 perforation
- initial 72-hr: 4.7% persistent GIT signs, 2.3% dyspnoea/coughing
- after 72-hr: 11.9% persistent GIT signs; 2.6% stricture
- stricture → successful balloon dilation in 3/4 (75%)
- mortality: 4.6% - 14/349 euthanasia, 2/16 death
- antacids and FB type not associated with complications
most removed orally with endoscopy 76.8%,
Winston III 2023 – modified Heller myotomy and Dor fundoplication for lower oesophageal
sphincter achalasia-like syndrome
LOS-AS – functional obstruction of LOS with increased muscle tone → retention of
saliva/ingesta → dilation
- myotomy → relief of contraction/tone
- fundoplication → low pressure valve over myotomy → prevention of reflux
- longitudinal myotomy across LOS (mod Heller myotomy)
- fundus folded over myotomy → serosa covers exposed oesophageal submucosa
(Dor fundoplication)
- outcome: 12/13 survival to discharge, 1 death due to aspiration pneumonia
- improvement in vomiting/regurg, QOL and BCS scores
- complications all associated with G-tube
Complications
associated with and outcome
of surgical intervention for treatment
of esophageal foreign bodies in dogs
Beer 2022
63 client-owned dogs, retrospective
perforation at surgery in 42/63 (66.7%)
- complications: intra-op 18/63 (28.6%), post-op 28/63 (50%)
- 3/63 oesophagotomy dehiscence
- survival to discharge 47/63 (74.6%); 81% if euth cases excluded
- mortality associated with: thoracotomy, placement of G-tube, pre-op perforation
- infrequent long-term vomiting/regurgitation in 5/20 (25%)
Diagnosis and treatment of gastrooesophageal
junction abnormalities in
dogs with brachycephalic syndrome
Vangrinsven 2021
prospective
- results suggest a beneficial effect of antacid treatment: improved digestive clinical signs and lesions in dogs
- addition of antacid treatment during the pre- and postoperative period may result in a faster and greater improvement
- The use of the
obstruction manoeuvre during endoscopic assessment in a control group revealed that gastro-oesophageal junction movements are negligible in healthy animals.
high prevalence of sliding hiatal hernia (9/21; 43%)
prevelence of GER 25%
By increasing the trans-diaphragmatic pressure gradient during endoscopy using temporary endotracheal tube obstruction, Broux et al. (2018) also showed increased detection of GJA, including sliding hiatal hernia in dogs with BS. control dogs used in this study
Surgical treatment of persistent right aortic arch with combined ligamentum arteriosum transection and esophageal diverticulum resection in three dogs
Nicholas J. Olson 2021
Resection of esophageal diverticulum secondary to PRAA utilizing
a TA stapler with suture overlay was technically feasible and did not seem
associated with early or late complications.
Outcome of dogs and cats with benign
oesophageal strictures after balloon
dilatation or stenting: 27 cases
(2002–2019)
Riz 2021
retrospective
Eighteen dogs and nine cats were included, representing 39 strictures. Balloon dilatation was
used as first-line therapy, with a good outcome in 59% of cases. Stents were placed in eight cases due
to stricture recurrence; 88% had a long-term satisfactory outcome. Short-term complications occurred
in six of eight cases; migration and aberrant mucosal reaction were uncommon. In three cases, progressive
mesh cutting during follow-up reduced discomfort and trichobezoars formation and improved
long-term stent tolerance
Delligianni 2020 – transdiaphragmatic gastrotomy for distal oesophageal foreign bodies
JAhAA
successful retrieval in 49/52 (94.2%)
- complications: major 8/52 (15.4%) - pleural effusion (2), aspiration pneumonia (2)
unsuccessful removal (3), oesophageal stricture (3),
cardiopulmonary arrest (1)
- major complications more likely with oesophageal FB
Characteristics and long-term outcomes
of dogs with gastroesophageal intussusception
Grimes
retrospective
13.2 months, and males (72%
28% dogs were euthanized without treatment
(88%) treated dogs survived to discharge; median
survival time was 995 days. At last follow-up, 15 of the 23 (65%) surviving
dogs remained alive and 8 (35%) had died for reasons related to persistent
regurgitation (n = 6)
Although persistent regurgitation
was common after treatment, a satisfactory outcome was possible
with medical management, including managed feedings and medications
Sx: left-sided gastropexy. Concurrent right-sided gastropexy was performed in 14 of these 22 (64%) dogs,
Sterman 2018 – likelihood and outcome of oesophageal perforation secondary to FB
15/125 (12%) perforation – not associated with body weight
- more likely with fish-hook (27%) vs other (6%)
- perforation more likely with longer delay to presentation
- survival: 13/15 (87%) survival to discharge, 8/13 no surgical intervention
- 100% survival without perforation
Marvel 2022 – thoracoscopic correction of PRAA with/without one-lung ventilation, n=22
10/12 OLV+, 7/10 OLV- dogs had successful LLA ligation
- no difference in sx time, complications or rate of conversion to open
Morgan 2019: Review
different type VIII and IX added to Joly 2008 (Types I-VI)
VIII - vessel joining aorta to right subclavian
IX - intercostal arteries
Advanced diagnostic imaging is strongly recommended
in the surgical planning for dogs with a clinical
suspicion of a vascular ring anomaly because the optimal
approach can vary, depending on the compressive
vessel or vessels.
The immediate postoperative prognosis may be guarded, and 1 in 5 dogs may fail to respond to surgery. However,
the available evidence suggests that most dogs that survive > 2 months after surgery will have an improvement in quality of life, although a small number may require
continued dietary management.
Retrospective comparison of short-term outcomes
following thoracoscopy versus thoracotomy for surgical
correction of persistent right aortic arch in dogs
Nucci 2018
10 thoracoscopy, 5 converted, 15 thoracotomy
- OLV initially used then found to be unnecessary
- median duration of sx and complications not different between groups
- median hospitalisation: thoracoscopy 1d (0.5-2), thoracotomy 2d (0.5-22)
Clinical findings, surgical treatment and long-term outcome of dogs and cats with double aortic arch: four cases (2005-2022)
M Rossanese 2022
cinti
2 cats, 2 dogs – right aortic arch larger than left in 4/4
- left 4th IC thoracotomy → ligation of lesser left aortic arch
- marked improvement in 4/4 → weight gain, excellent outcome and QOL
