Equine Respiratory Surgery Flashcards
what system in the horse is often a limiting factor in performance?
respiratory system
what type of pathology is common in horses?
upper respiratory
what has evolved to maximise air flow in horses with upper airway issues?
surgical techniques to allow maximal air flow in these horses
how is a diagnosis of upper respiratory tract pathology in horses made?
dynamic endoscopy
what is a key benefit of dynamic endoscopy?
larynx and pharynx can be examined during fast work which is where performance is likely to be sub optimal
what are the 2 main types of dynamic endoscopy?
overground
treadmill
what are the main elective surgical procedures of the equine URT?
ventriculocordectomy aryepiglottic fold resection prosthetic larygoplasty laryngeal advancement soft palate cautery epiglottic entrapment release arytenoid chondritis excision sinus surgery tracheotomy
what are the main emergency surgical procedures of the equine URT?
emergency tracheostomy
occlusion of artery for gutteral pouch mycosis
trauma
thoracic drain placement
what sort of animals are often in hospital for URT surgery?
elite athlete - will likely be fit and highly strung
what should be assessed during the clinical exam of a URT patient?
whole horse but respiratory tract especially
how long should horses be starved before GA or sedation?
2 hours
what is involved in pre-op planning for URT surgery?
procedure and kit required position - standing or lateral/dorsal contingency plans if things go wrong recovery plan what will be needed post op
what are the advantages of standing sedation for URT procedures?
reduces GA risks
may reduce costs
anatomical advantages
less facilities and experts required
what are the anatomical advantages of surgery under standing sedation?
access/position reduced haemorrhage (especially sinuses)
what are the disadvantages of standing sedation for URT surgery?
not all horses have suitable temperament
less control of situation if complications arise
need to control the environment (especially movement and noise)
duration is limited so speed is crucial
may still need a GA if there are complications
where is standing surgery often performed?
in stcoks
what premed may be given to horses before sedation?
ACP
what drugs may be given as a loading dose for standing sedation in horses?
alpha 2 agonists (xylazine, detomidine)
opioids (butorphanol, methadone)
what drugs may be used as a CRI for standing surgery?
alpha 2 agonist only
what must be considered when placing fluid lines and CRI?
location - will it interfere with surgery and is it accessible
avoid causing paralysis of nerves on both sides
what will be given alongside sedation for standing procedures?
LA - nerve blocks, local infiltration
what is one of the most challenging aspects of standing surgery?
multiple pieces of equipment required
fluids and CRI
lots of cables/wires etc
visualisation and access needed
when should equipment be set up for standing sedation?
before the horse arrives
what area of the horse should be prepared for a tie back procedure?
ventral neck and caudal mandible
what is a sinus flap used to treat?
sinus empyema
sinus cysts
ethmoid haematoma
maxillary tooth repulsion
what surgery involves a large amount of haemorrhage?
maxillary tooth repulsion
how is a sinus flap performed?
reflect skin
remove bone
gross viewing or endoscope
what are the advantages of general anaesthesia?
more control of the horse (safer with fractious patients) generally good access and visualisation less time pressure but will take longer less movement/noise sensitive oxygen is available
what are the disadvantages of GA for horses?
cost, expertise, time, facilities
risk of death under GA is 1% in healthy horses
airway supervision required at all times
duration
what elective procedures may be performed under standing sedation?
ventriculocordectomy aryepiglottic fold resection prosthetic larygoplasty epiglottic entrapment release arytenoid chondritis excision sinus surgery tracheotomy
what surgical procedures can be performed under GA?
ventriculocordectomy aryepiglottic fold resection prosthetic larygoplasty epiglottic entrapment release arytenoid chondritis excisionlaryngeal advancement soft palate cautery
what surgical procedures are usually only performed under standing sedation?
sinus surgery
tracheotomy
what emergency surgical procedures are usually only performed under standing sedation?
emergency tracheostomy
trauma
thoracic drain placement
what emergency surgical procedures are usually only performed under GA?
occlusion of artery for gutteral pouch mycosis
where is laser surgery performed?
transendoscopically
what must be worn when involved with laser surgery?
PPE is vital - goggles
what safety feature do all lasers have?
key for locking mechanism which should be stored separate to laser
why should lazers not be used with nitrous oxide?
fire hazard
why is suction needed in laser surgery?
toxic gases are produced including xylene and toluene
what surgical procedures can be performed by laser?
ventriculocordectomy
aryepiglottic fold resection
sinus surgery
what is happening during epiglottic entrapment?
epiglottis trapped in fold of mucosa over the soft palate
what is often seen following laser epiglottic entrapment surgery?
abscessation
what are the main patient considerations intra-operatively?
patent airway is essential
protect from aspiration
obstructions may compromise airway
how can the airway be protected from aspiration?
cuffed ET tube
suction available
use swabs
drainage
what are the issues with soft palette cautery?
welfare issue
consists of burning the soft palate
leads to considerable pain and patient is unable to eat
what is the aim of soft palate cautery surgery?
creates scarring to tighten the soft palate to prevent dorsal displacement
what is the key health and safety risk with soft palate cautery?
no nitrous oxide to be used as is a fire risk
what are the main post operative considerations following respiratory surgery?
swellings may compromise airway
inhalation pneumonia is a risk
what must always be available near the stable of a respiratory surgery patient?
emergency tracheostomy kit
what should all respiratory surgery patients be fed?
moist/soaked hay or haylege for all
where should food be positioned for horses following respiratory surgery?
high for tie forward
lowered (off the floor) for all others
why does food need to be fed from high up in tie forwards patients?
avoids pressure on the sutures
why does food need to be fed from the floor for all other respiratory surgery patients?
allows airway drainage
what analgesia is usually used for pain management following respiratory surgery?
NSAIDs
topical throat spray
what is found within topical throat spray?
glycerin
dimethyl sulfoxide
dexamethasone
what happens to the wound made in the larynx post surgery?
left open to drain as surgery is classed as contaminated
what is often placed at the end of laryngeal surgery for recovery and left overnight?
laryngostomy tube
what is the purpose of a post op laryngostomy tube?
avoids laryngospasm and provide O2
why must larygostomy tubes be occulded before they are removed?
to ensure that the patient can breathe without the tube in place
under what conditions must a chest drain be placed?
surgical
what is the position of chest drains?
ventral if fluid
dorsal if gas
uni or bi lateral
how can level of fluid or gas in the patient be monitored?
marker pen or clipper marks on patients side
what is thoracoscopy used for?
investigate and treat pleural/pulmonic disease (e.g. pleuropneaumonia exudate, neoplasia, haemothorax, pyothorax)
what conditions is thoracoscopy performed under?
standing sedation
what procedure should thoracoscopy be set up as?
laparoscopy
what 2 pieces of equipment are essential for thoracoscopy?
suction
oxygen
what is a tracheotomy?
temporary emergency placement of tube in trachea
what type of tube is used for a tracheotomy?
plastic
what is a tracheostomy?
long standing use for tube/opening in trachea
what is a tracheostomy formed from?
stoma or metal tube
when is an emergency tracheotomy needed?
tor provide a functional airway
what may affect the airway and cause need for tracheotomy?
direct obstruction of airway
external obstruction
what disorders of the URT can cause direct obstruction of the airway?
laryngeal obstruction, paralysis, spasm
oedema
tracheal collapse
what can cause external obstruction of the airway?
abscesses (e.g. strangles affecting retropharyngeal lymph nodes)
oedema following trauma
what equipment is required for an emergency tracheotomy?
tracheostomy tube clippers sterile gloves LA gauze swabs soaked in 4% CHG scrub gauze swabs soaked in SS no 10 scalpel blade suture material
