SA surgery and nasal disease Wrap Up Flashcards
What is Sturtor?
reverberate soft palate, like a snore
What is Stridor?
obstruction in the larynx or cranial trachea, like laryngeal paralysis
What is Reverse sneezing?
often describe it wrong by owners, reflex produced to clear nasopharynx if FB in it, nasopharyngitis, dogs and cats have reverse sneeze, head often extended, on all fours and can go cyanotic, owners difficulty to describe this, like snorting for phlegm?
When v bad, need to anaesthetise otherwise will faint due to lack of oxygen and do not want it to become cyanotic
What are some primary problems that can cause and associated with nasal disease?
- Stenotic external nares
- Relative overlength and hypertrophy of the soft palate
- Relative oversize of the tongue
- Tracheal hypoplasia/stenosis
- Sliding hiatal hernia
What are some secondary problems associated with nasal disease?
- Tonsillar hypertrophy
- Everted laryngeal ventricles/saccules
- Laryngeal collapse
- Pharyngeal collapse
- Glosso-epiglottic mucosa displacement
- Scrolling of epiglottic cartilage
- Vomiting/regurgitation
Pathophysiology – tracheal hypoplasia?
- If we can, x-ray the case: two lateral inflated films
- Look for concurrent airway dz i.e. aspiration pneumonia
- This x=ray- very small narrow tracheal, congenital hypoplasia as part of BOAS
- Cannot surgically manage this
Discuss stages of laryngeal collapse?
- Stage 1 - laryngeal saccule eversion
- Stage 2 - medial deviation of the cuneiform cartilage and aryepiglottic fold or aryepiglottic collapse
- Stage 3 - medial deviation of the corniculate process of the arytenoid cartilages or corniculate collapse
Can get collapse of artenoid cartilage (stage 2)
Discuss external nasal aperture stenosis?
- Brachycephalic cats, get stenotic nares too
- Stenosis of the external aperture of nose
- Undergo rhinoplasty by doing wedge-resection
- This is the first point of stenosis: external nares. Significant point of airway obstruction so is important surgical procedure
Rhinoplasty- wedge-resection:
Discuss soft palate surgery techniques?
Surgery of soft palate: staphylectomy: à
- Soft palate resection
- Through mouth, dog positioned so get access to back of throat
- Trim to level of tonsils at crypts
- More common surgery of the two
OR soft palate palatoplasty –> (second)
- Surgeon discretion
- Taking thickness out palate and shortening at same time
- Incise palate, roll forward and cut muscle layer out
Discuss tonsillectomy?
Tonsillectomy: ‘meat in the box’
- The more meat you can remove, the better the afterwards
- Tonsils enlarged and in the way, can be removed easily to improve size of airway
- Not everyone does this
Discuss Idiopathic acquired laryngeal paralysis?
- Stridor common presentation
- Definition is Noise on inspiration
- But dog in video had: Noise on inspiration and expiration
- When obstruction so severe, can get expiratory noise- common with laryngeal paralysis
- Pathognomonic
Horses tend to get unilateral hemiplasia, they tend to get a left sided laryngeal paralysis as longest laryngeal nerve, dogs however, get idiopathic bilateral laryngeal paralysis (both cartilages paralysed).
Discuss arytenoid movement?
- Inspiration – cartilages are abducted
- Expiration – cartilages are adducted (air break)
- Expiration at exercise – cartilages are abducted
- Size of the rima glottidis is determined by the respiratory needs of the animal
Degree of abduction – depends on how much air flow required (exercise etc.)
What is the aetiology of laryngeal paralysis?
Aetiology – exact aetiology remains unclear
- Neurogenic atrophy of the intrinsic laryngeal muscles
- Dysfunction of the recurrent laryngeal nerves
- Generalised peripheral neuropathy involving long and large diameter nerve fibres
- Central nervous system origin
- Hypothyroidism (?)
The dz in the dog, is most commonly presented as idiopathic dz.
Often older aged dogs in large breeds – i.e. 12y/o Labrador retriever
Clinical signs of laryngeal paralysis?
Clinical signs:
- Stridor
- Cough
- Dyspnoea
- Change in phonation (bark)
- Exercise intolerance
- Collapse
- Signs are related to the severity of the paralysis present
- Most dogs present late in the course of the disease
- Clinical signs worse when the dog is hot, excited and exercised
- Anything putting resp rate up will make them worse i.e. stress, temperature, exercise, excited
Diagnosis of laryngeal paralysis?
Characteristic clinical signs
- Auscultation of the larynx and the thorax
- Laryngoscopy (under a light plane of general anaesthesia)
- Straight-bladed laryngoscope (Miller)
- With laryngoscopy
- Propofol anaesthesia
- Using laryngoscope
- Looking to see movement of aretnoid cartilage
- If over anaesthetise, obliterate artenoid movement
- The animal should be just about swallowing
- As air flows through larynx, drop in pressure, draw aretenoid cartilages together and may get paradoxical movement as may mistake this for noimral movement
- Common dog/animal has neurological signs alongside: dysphagia, dysfunction and HL dz
Diagnosis cont’d:
- Survey inflated radiographs of the thorax
- Neurological examination
- Routine haematology and blood biochemistries
- Thyroid function testing?
- Concurrent disease:
- Cardiac
- Lower respiratory tract
- Dysphagia
- Megaoesophagus
- hypothyroidism
What are the Conventional survey radiographs for suspected tracheal collapse?
Conventional survey radiographs
- Include neck in radiography
- Lost tracheal shadow as trachea has collapsed
- Commonly affects towards the thoracic inlet:
Diagnostic: endoscopy
- Looking to see collapse and severity of collapse
How does tracheal collapse appears on endoscopy?
What is the surgical management of tracheal collapse?
Surgery: open ring prosthesis
- Put a number of ridged plastic rings externally/extralumial and force trachea back into normal shape with the rings round it
- Easier for cervical region
Stenting surgery:
- Self expanded stents
- Intra-luminal stent
- Expands to fill whatever lumen you put it into
Complications:
Chronic cough because stent doesn’t sit well in mucosa
