Surgical Disease of the Oesophagus Flashcards
What feature of the oesophagus protects against damage by abrasion?
Tough lining of stratified squamous epithelium (mucosa)
What allows effective peristalsis to move food/liquids to the stomach and keep the oesophageal lumen empty?
two well developed coats of skeletal muscle (tunica muscularis) that spiral and cross each other in the oesophageal wall
What property of the oesophagus allows marked distension of the oesophagus when swallowing large food boluses?
longitudinal folds in the collapsed empty state
What feature of the oesophagus allows the entry and exit respectively of food and liquids and limit the presence of food/liquid within the oesophagus to a short duration of time after swallowing?
The upper and lower oesophageal sphincters
The structure of the oesophagus is different in the cat and dog.
Is this statement true or false?
True
The canine oesophagus has skeletal muscle throughout its length whilst the terminal few centimetres of the feline oesophagus has smooth muscle within the tunica muscularis.
What are the primary pathophysiological mechanisms of disease of the oesophagus? (4)
- Inflammation
- Dysmotility
- Obstruction - intraluminal, mural, extramural
- Traumatic injury
Name the pathophysiological mechanism for chronic regurgitation/ingestion of caustic or hot substance?
Inflammation
Name the pathophysiological mechanism for megaoesophagus.
Dysmotility
Name the pathophysiological mechanism for Oesophaeal FB?
Intraluminal obstruct
Name the pathophysiological mechanism for oesophgeal stricture?
Mural obstruct
Name the pathophysiological mechanism for vascular ring anomaly
Extramural obstruct
Name the pathophysiological mechanism for stick injury/cervical dog bite wound
Traumatic
Main 2 clinical signs of oesophageal disease?
Regurgitation
Dysphagia
Common but not main signs of oesophageal dx?
Cough
Dyspnea
Ptaylism
Fever
Lower appetite
Pathogenesis of nasal discharge with oesophageal dx?
Aspiration of food contents into the nasopharynx and/or trachea is common in patients with frequent regurgitation –> Inflammatory rhinitis
Pathogenesis of pneumonia with oesophageal dx?
Aspiration of food contents into the nasopharynx and/or trachea is common in patients with frequent regurgitation –> Aspiration pneumonitis
How to possible investigations into oesophageal disease? (8)
- History and CE
- Haematology + biochem
- Fluroscopy barium swallow
- Plain cervical xrays
- Thoracic xrays
- +ve contrast studies
- CT
- Oesophagoscopy
Which reflex will you assess to check if a patient is able to swallow?
Gag relfex
How to perform gag reflex?
Open patient’s mouth, touch patient’s larynx/tongue base.
Which cranial nerves does the gag reflex access?
Cranial nerves 9 and 10
Other than haem/biochem, what specific blood tests could be performed to investigate the oesophaus?
Ach antibodies - Myasthenia Gravis
What are the challenges of Fluroscopy? (3)
- Staff must be present within the room during radiation exposure to restrain the patient and to keep the fluoroscopy beam focussed on the patient, therefore there is a risk of radiation hazard to staff;
- The study is dependent on the patient eating and being co-operative;
- The patient is conscious, and the study is dependent on the patient remaining reasonably still.
Reasons the oesophagus has higher rates of complications historically. (4)
- does not have a serosa;
- has a segmental blood supply;
- has no omentum;
- is in constant motion due to swallowing and breathing.
Why may a serosal layer play a role in healing?
The serosa allows formation of an early fibrin seal by providing a source of pluripotent stem cells therefore may be important
Which area of the oesophagus has no layer equivalent to the serosa and therefore possibly effect healing?
Cervical
What overlays the thoracic oesophagus which is thought to act like the serosa?
Mesothelium
Experimentally, how necessary has the serosa been shown to be for visceral healing?
Unnecessary
What has latest data shown the blood supply of the oesophagus to be like?
It is now thought that disrupted oesophageal healing is more likely to arise if the intramural blood vessels are disrupted rather than the segmental blood supply.
How can we solve the lack of omentum in the oesophagus region?
The omentum can be lengthened, tunnelled through the diaphragm and used to support thoracic oesophageal surgical wounds.
Why is constant motion a poor reason for the low healing rate in the oesophagus?
stomach/intestines undergo peristalsis and heal
How many tension come about with an oesophageal wound?
Resect and anastomosis
How many Halstead principles are there?
7
What are Halstead’s surgical principles?
Strict aseptic technique
Gentle tissue handling
Meticulous haemostasis
Preservation of the blood supply
Closure with minimal tension on tissues
Anatomical closure with accurate tissue apposition
Obliteration of dead space
What should be done to the oesophagus before incision?
Suction the oesophageal lumen prior to incising the oesophagus, or immediately after incision to reduce local contamination of tissues with oesophageal contents;
Where should be incised on the oesophaus? (2)
- Incise through healthy oesophageal tissue;
- Choose the most advantageous approach to allow good exposure and access;
Which direction should an oesophageal surgical approach be?
Make a longitudinal oesophagotomy incision rather than a transverse incision because this is less likely to cause narrowing/stricture in healing;
What layer must be included when closing oeosphagus?
Submucosa
How many layer closure is recommended for oeosphagus?
1
Where should the knots be tied when closing oesophagus?
Extraluminal