URT surgery in small animals Flashcards
(68 cards)
1
Q
Primary factors for requiring URT surgery
A
- stenotic external nares
- relative over length of the soft palate
- relative oversize of the tongue
- tracheal hypoplasia/stenosis
- sliding hiatal hernia
2
Q
Secondary factors for requiring URT surgery
A
- hypertrophy of the soft palate
- tonsillar hypertrophy
- everted laryngeal ventricles/saccules
- laryngeal collapse
- pharyngeal collapse
- glossy-epiglottic mucosa displacement
- scrolling of epiglottic cartilage
- vomiting/regurg
3
Q
Tracheal hypoplasia
A
- congenital malformation that causes a small trachea
- Not much you can do about this.
4
Q
Stage 1 laryngeal collapse
A
= laryngeal saccule eversion
5
Q
Stage 2 laryngeal collapse
A
= medial deviation of the cuneiform cartilage and aryepiglottic fold or aryepiglottic collapse
6
Q
Stage 3 laryngeal collapse
A
= medial deviation of the corniculate process of the arytenoid cartilages or corniculate collapse
7
Q
External nasal aperture stenosis
A
When the alar folds become displaced medially, causing the nasal opening to be narrowed
8
Q
Nasal aperture stenosis surgery
A
Rhinoplasty (wedge-resection) or alar fold resection
9
Q
Alar fold resection
A
Removal of the alar fold internally to create a bigger opening. No published work to say whether alar fold resection or rhinoplasty is better, but ct shows it creates an obvious wider opening
10
Q
Surgery of the soft palate
A
- partial staphylectomy
- folded-flap palatoplasty
- tonsillectomy
11
Q
Tonsillectomy
A
Tonsils can also get in the way of the airway - so they can be removed to get rid of as much obstruction as possible
12
Q
Partial staphylectomy
A
- to reduce the length of the soft palate
- cut a portion of the palate away, and making it shorter -> generally making it the length of the tonsillar fossa.
13
Q
Folded-flap palatoplasty
A
- partial thickness incision and unfold the palate so you can trim out some of the muscle in the palate to make it thinner, and when you pull it forward you can shorten it as well
14
Q
Idiopathic acquired laryngeal paralysis - signalment, CS
A
Commonly seen in larger breed older dogs, e.g. GRets, labs, setters.
Stridor, squeakier than normal laryngeal paralysis. Big abdominal heave as can’t get the air in. The maximum noise heard on the larynx. Can hear on the lungs but it would be referred noise from the larynx
15
Q
Arytenoid movement on inspiration
A
Cartilages are abducted
16
Q
Arytenoid movement on expiration
A
Cartilages are adducted
17
Q
Arytenoid movement on expiration during exercise
A
Cartilages are abducted
17
Q
Aetiology of laryngeal paralysis
A
- neurogenic atrophy of the intrinsic laryngeal muscles
- dysfunction of the recurrent laryngeal nerves
- generalised peripheral neuropathy involving long and large diameter nerve fibres
- CNS origin
- hypothyroidism?
18
Q
The size of the rima glottidis is determined by…
A
the respiratory needs of the animal
19
Q
Clinical signs of laryngeal paralysis
A
- stridor
- cough
- dyspnoea
- change in phonation (bark)
- exercise intolerance
- collapse
- signs are related to the severity of the paralysis
- most dogs present late in the course of the disease
- clinical signs are worse when the dog is hot, excited and exercised
20
Q
Diagnosis of laryngeal paralysis
A
- characteristic clinical signs
- auscultation of the larynx and the thorax
- laryngoscope (under light GA)
- straight-bladed laryngoscope (Miller)
- survey inflated radiographs of the thorax
- neurological exam
- routine haem and biochem
- thyroid function testing?
21
Q
Laryngeal paralysis on laryngoscope
A
- No abduction of the larynx during inspiration
- Can end up with paradoxical movement of the larynx -> it looks like its moving/closing but its due to the drop in air pressure due to breathing in
22
Q
Concurrent disease for laryngeal paralysis?
A
- cardiac
- LRT
- dysphagia
- megaoesophagus
- hypothyroidism
23
Q
Emergency medical management of laryngeal paralysis
A
- Rest/calm
- supplemental oxygen
- cooling (as often hyperthermic)
- sedation (low dose medetomidine)
- IV access
- IV steroids?
- anaesthetise for tracheostomy tube placement?
24
Surgical management of laryngeal paralysis
Arytenoid lateralisation (tieback)
25
Arytenoid lateralisation (tieback)
Tying back 1 of the arytenoid cartilages. Aims to widen the rima glottidis and prevent dynamic collapse of the arytenoid cartilage. almost invariable performed as unilateral procedure
26
Why do you not tieback both arytenoid cartilages in laryngeal paralysis for dogs?
They are likely to aspirate
27
Post-op complications for arytenoid lateralisation
- seroma formation
- aspiration pneumonia
- inadequate lateralisation
- suture failure/recurrence
- change in bark
28
Post-op care for arytenoid lateralisation
- observe feeding and drinking
- strict rest for 2-3wks
- antibiotics
- analgesics
- harness
28
Common breeds that have tracheal collapse
Toy breed dogs, classically Yorkies
29
Tracheal collapse
- Generally refers to a condition of an excessive collapsibility of the trachea which usually results in dorsoventral flattening of the tracheal lumen
- The cartilages of the trachea fail
30
Clinical signs of tracheal collapse
"goose honk" cough, exercise intolerance, tracheal pinch will set it off
31
Tracheal collapse grade I
becomes more D shaped
32
Tracheal collapse grade II
more D shaped
33
Tracheal collapse grade III
becomes flatter
34
Is it common to have different stages of tracheal collapse throughout the trachea?
Yes
35
Tracheal collapse grade IV
goes back in on itself
36
Why use inhaled meds?
More targeted and safer for the pt
36
With tracheal collapse, where is commonly affected?
The level of the thoracic inlet
36
Medical management of tracheal collapse
- Anti-tussives (anti-cough)
- bronchodilators
- antibiotics (if required on BAL results)
- NSAIDs
- inhaled corticosteroids and/or bronchodilators
37
Surgical management of tracheal collapse?
- if medical management doesn't work
- open ring prosthesis
- stenting
38
Open ring prosthesis
external plastic rings to the trachea
39
Stenting
Endoluminal stening. after a few weeks/months it will grow into the mucosa / integrate into the trachea so it won't be as obvious to see
40
Nasal disease differentials in dogs
- FB
- neoplasia
- aspergillosis
- chronic rhinitis
40
Causes of chronic rhinitis in dogs
- dental disease?
- allergy?
- often called hyperplasticity rhinitis -> don't know what causes them
41
Investigation of nasal disease in dogs
- CT
- rhinoscopy
- radiography
- nasal flush
42
Epistaxis differentials
- Nasal disease
- coagulopathy
43
What is a common cause of chronic nasal discharge in cats?
- Chronic rhinitis
43
Chronic rhinitis in cats
- inflammation and swelling of the conchae, there's increased mucus production and usually secondary infection, mucopurulent secretion may contain blood.
- can be mild or severe
- in some cats the inflammation continues and becomes more severe, resulting in loss of conchae
44
Endoscopically, what do cats with chronic destructive rhinitis look like?
- similarly to dogs with aspergillosis of the nasal passages
45
What virus has been suggested to play a role in chronic nasal inflammation, resulting in destructive rhinitis?
feline herpesvirus 1
46
Why are dogs more likely to get a nasal FB rather than a nasopharyngeal FB (like cats)?
they are more likely to sniff something into their nostrils.
47
Causes of chronic rhinitis in cats (and ~%)
tumours - 37%
polyps - 4%
rhinitis - 25%
FB - 28%
miscellaneous - 2.5%
undiagnosed - 2.5%
47
Fungal rhinitis
Aspergillosis most likely. sinonasal aspergillosis.
mainly seen in dogs.
common cause of nasal dz. less common than neoplasia
48
Possible predisposing factor for fungal rhinitis
underlying damage to the nose
48
Breeds more likely to get fungal rhinitis
medium to long nosed breeds
48
An example of somewhere can get a fungal infection from
horses muckheap
49
Where is fungal rhinitis generally restricted to?
the nasal cavity and sinuses
50
Where is fungal rhinitis destructive to?
turbinates. it can also erode frontal bones and the cribriform plate
51
Clinical signs of fungal rhinitis
nasal discharge (mucopurulent, unilateral -> bilateral, intermittent epistaxis)
- ulceration or depigmentation of nasal planum
- pain on palpation
- sneezing
- facial deformity?
- neurological signs?
52
Diagnosis/tests for fungal rhinitis
- history
- clinical signs
- blood tests (coagulation profile)
- diagnostic imaging (radiography of nose and sinuses, CT/MRI)
- rhinoscopy (rigid/flexible, guided biopsy)
- cytology
- serology?
53
Oral antifungals for fungal rhinitis tx
- 'azoles
- requires prolonged tx
- side effects (anorexia, V+) common
- not recommended
53
Why is serology not great for fungal rhinitis diagnosis?
False negatives and positive - so very unreliable
54
What could be seen on rhinoscopy for fungal rhinitis?
fungal plaques - look like mould
55
Is fungal rhinitis easy to treat?
- no
56
Treatment for fungal rhinitis
- oral anti fungal agents
- topical therapy
57
Topical therapy for fungal rhinitis tx
- preferred option
- enilconazole
- clotrimazole
57
Delivery methods for tx of fungal rhinitis
- catheter placement in frontal sinuses via surgery (~80% successes - treat 7-14d bid)
- debridement
- infusion of nasal cavities under GA (not as good success rate but cheaper)
