Surgical conditions of the respiratory tract - SA 1&2 Flashcards
What divides the airway into URT and LRT?
junction between the cricoid cartilage and the trachea (larynx is therefore URT)
Why aren’t any surgical interventions of the airways considered D1Ss?
all have the potential to cause life-threatening inflammation or haemorrhage that can obstruct the airway
Name 3 conditions of the rhinarium
- congenital deformities (stenotic nares and cleft lip)
- lacerations/trauma
- neoplasia (SCC and MCT)
What raises your index of suspicion for SCC in rhinarium?
non-healing ulcers here
What are broad causes of nasal discharge? 6
- chronic hyperplastic rhinitis
- trauma
- dental disease
- intranasal neoplasia
- mycotic rhinitis
- FBs
Breed predisposition - chronic hyperplastic rhinitis
Whippets, Dachshunds and cats
Tx - severe and intractable chronic hyperplastic rhitinits
rhinotimy and turbinectomy
What should you do if a patient has trauma-induced nasal discharge? 4
- little need for orthopaedic fixation
- ensure maxillary fractures are reduced to maintain dental occlusion
- check later fro acquired palatine clefts
- occasionally as sequestrum may form so check radiographs for this and also osteomyelitis
Describe nasal discharge associated with dental disease
- mucopurulent, occasional epistaxis
- unilateral
- periapical lucency on radiography (occasionally these are incidental)
- lesions
What tumours are most common in the nose?
Most are malignant - solid carcinoma or adenocarcinoma, chrondo/fibro/osteo-sarcoma
What is a benign polypoid rhinitis?
very rare but clinically indistinguishable from nasal malignancies except histopath. Good prognosis following polyp removal
What causes mycotic rhinitis 2
Aspergillus and Penicillium
Define sinusotomy
surgical incision into a skull sinus
Treatment - mycotic rhinitis
If non-surgical treatment fails, surgical placement of irrigation tubes via sinusotomy may facilitate successful Enilconazole (imidazole fungicide) therapy
CS -FBs in nose
sudden onset sneezing. serous discharge, may progress to mucoid/purulent discharge if chronic
How common are nasal FBs?
not as common as many clients suspect!
How are defects in the secondary palate (hard and soft palate) characterised?
Congenital or acquried
Clinical signs - congenital defects of the secondary palate
- noticed early in life
- fail to thrive
- unable to suckle succesfully
- often have nasal return of milk
- aspiration pneumonia signs
- mild cases may only show chronic nasal discharge
Clinical signs - acquired defects of the secondary palate
- chronic nasal discharge and sneezing due to constant impaction of food material in nasal cavity*
- aspiration pneumonia
Treatment - secondary palate defects
surgical repair when CS present. often complicated
Define BAOD
Brachycephalic Airway Obstruction Syndrome
What is BAOD
a group of conditions commonly found amongst brachycephalic breeds. Abnormalities are often present at birth but clinical disease may not become a problem until middle age.
What are the primary and secondary BAOD pathologies?
PRIMARY - stenotic nares, long soft palate
SECONDARY - eversion of the lateral laryngeal ventricles, laryngeal collapse, others (tracheal hypoplasia, redundant pharyngeal mucosa, scrolling of the epiglottis)
CS - BAOD
MILD: execise intolerance or dyspnoea following stress or excitement, exacerbation by heat and stress
SEVER: loud noise on inspiration and expiration (steror) and visibly small external nares, poor heat dissipation (–> pyrexia) and vicious cycle develops
What is an acute obstructive crisis?
precipitated by heat or extreme stress in BAOD dogs, causes cyanosis and collapse
Diagnostic considerations BAOD
Rule out other causes fo inadequate ventilation/tissue perfusion
- PE - rule out CV and pulmonary disease (auscultation difficult because of referred URT noise)
- Haematology and serum biochemistry
- thoracic radiographs
- lateral radiograph of larynx
- pharyngeal and laryngeal exam
Treatment - BAOD
- early in day (full day supervision after)
- best to follow examination of URT with surgery if necessary rather than giving a second anaesthetic
- rhinoplasty
- staphylectomy
- resection of everted mucosa of lateral laryngeal ventricles
- temporary tracheostomy (optional)
Post-op care - BAOD treatmetn
- routine tracheostomy management (if used)
- intensive observation and care
- keep animal as quiet as possible for following 7-10 days
What is tracheal hypoplasia? Breed predisposition?
- narrowed trachea
- bulldogs
- generally can live a normal life providing upper airway is in good condition. occasionally very severely affects animals
Define tracheotomy
a temporary tracheostomy
Indications - tracheotomy (temporary tracheostomy)
- precaution prior to some upper airway surgery or in an emergency situation to bypass life threatening upper airway obstruction
- constant supervision
- selection of tubes available (low pressure cuffed type is best for animals to be maintained under anaesthesia or on a ventilator. Non-cuffed type that have a removable central sleeve to facilitate cleaning for chronic use. Selection of sizes).
Outline placement of a tracheotomy (temporary tracheostomy) tube
- septic (if non-emergency)
- ventral midline incision (neck), 2-4cm caudal to larynx
- long stay sutures placed around tracheal rings with a separation of two tracheal rings (2-0 monofilament)
- transverse incision between 4th and 5th tracheal rings between the stay sutures
- tube placed in tracheal lumen
- skin closed around the trachoestomy tube and the tube is secured by passing umbilical tape or similar around the dog’s neck. The pre-placed stay sutures are tied in a loose bow.
How does a tracheotomy animal need to be cared for? 5
- constant monitoring
- insert sleeve removed and cleaned every 2 hours
- nebulisation every 4 hours
- limit physical activity
- suction tube (if plugged but increases inflammation)
When is a tracheotomy tube removed?
once the dog has demonstrated adequate upper airway air movement (air around tube)
How is the tracheotomy tube removed?
with the dog conscious and the hole left to heal by 2nd intention
What are the 3 main conditions of the larynx?
- laryngeal paralysis
- laryngeal neoplasia
- granulomatous laryngitis
What are the 3 aetiopathologies for laryngeal paralysis?
- CONGENITAL - Bouvier des Flandres, Husky
- ACQUIRED (KNOWN) - trauma, neoplasia, secondary to polyneuropathy/polymyopathy (hypothyroidism etc)
- ACQUIRED (IDIOPATHIC) - labrador, retriever
CS - laryngeal paralysis
- chronic progressive exercise intolerance
- dysphonia
- increased resp. noise (especially inspiratory, stridor)
- chronic cough
- cyanosis and collapse (heat, stress, excitement)
What should you do in an obstructive crisis of laryngeal paralysis 5
- often hyperthermic –> cool IV fluids, external body cooling
- sedation
- oxygen supplementation
- occasionally rapid anaesthetic induction and orotracheal intubation
- tube tracheostomy will permit complete patient evaluation prior to definitive treatment.
How should you further investigate a stable patient with laryngeal paralysis? 4
- careful PE
- haematology and biochemistry (con/intercurrent disease)
- thoracic radiographs (pulmonary disease, mediastinal mass)
- careful evaluation of laryngeal function under light plane of anaesthesia
What should you do if you localise the laryngeal paralysis to the left arytenoid?
suture the arytenoid to teh thyroid (lateralisation) or cricoid (formation of prosthetic cricoarytenoid dorsalis muscle = laryngoplasty)
Post - op care after laryngeal paralysis treatment. 4
- avoid excitement
- keep tracheostomy tube handy in case post-op oedema causes further obstruction
- typically cough for 2-3 weeks following this procedure
- risk of aspiration pneumonia (greater with bilateral surgery)
What is the treatmetn for laryngeal paralysis?
left arytenoid lateralisation
Outline laryngeal neoplasia
rare, mostly malignant
- Congenital rhabdomyosarcoma (oncocytoma)
- SCC
- adenocarcinoma
- fibrosarcoma
- lymphoma (cat)
CS - laryngeal neoplasia
- dysphonia
- sonorous respiration
- exercise intolerance
- respiratory distress
- may be indistinguishable from laryngeal paralysis*
What is granulomatous laryngitis?
dog and cat
affected animals present in similar way to laryngeal paralysis and laryngeal tumours
presence of this disease mandates BIOPSY
Name 2 surgical conditions of the trachea
- tracheal collapse
- tracheal trauma
What breeds does tracheal collapse tend to affect?
toy and small terrier (esp. YT)
What is tracheal collapse the result of? 3
poor tracheal cartilage development and poor tracheal conformation (low GAGs and low cellularity). May be exacerbated by LRT infections, heart disease and/or laryngeal dysfunction.
When does tracheal collapse cause a problem?
although present from birth, the disease causes a clinical problem in mid to late life (4-7 years). collapse is worsened by obesity.