Equine Anaesthesia- Recovery Flashcards
What are examples of recovery complications?
- colic
- airway obstruction
- trauma- orthopaedic, soft tissue
- neuropathy- central and peripheral
- catheter problems
- myopathy (EPAM)
Describe equine post-anaesthetic myopathy
- swollen, hot, hard muscles
- myoglobinuria can be seen in some cases
- may affect ability to stand after anaesthetic
- may be delayed in onset by a few hours
Why does myopathy develop?
failure of perfusion/ oxygen delivery to muscles
hypotension increases risk
hypoxaemia
long anaesthesia
heavier horses
positioning of horse- leads to compression of blood vessels and stretch occlusion
How can EPAM be treated?
NSAIDs and opiods
Fluids can help to reduce any potential damage of myoglobin area
How can EPAM be prevented?
Minimise duration of anaesthesia
Position and pad well- support the legs of patient with air bags
Maintain 02 delivery to muscles
Describe peripheral neuropathies (neuropraxis)
Pressure or traction on nerve
Usually resolve over time but can sometimes be permanent
Tends not to have heat or hardness associated with the muscles
Describe spinal cord myelomalacia
Rare More common in young male horses More common after dorsal recumebency No apparent problems during anaesthesia Aetiology unclear
Define stridor
inspiratory
high pitched noise
Define stertor
expiratory
heavy snoring sound
Define paradoxical ventilation
When as the thorax rises instead of the abdomen also rising as the diaphragm moves caudally the abdomen comes in as the lungs are not able to be filled with air and instead fill with abdominal contents
What can be seen as airway obstruction?
Nostril flaring
Paradoxical ventilation
Absence of airflow at nostril
Stridor or stertor
What can be causes of airway obstruction?
Nose in corner of box
Nasal congestion
Laryngeal paralysis
Airway swelling
How can airway obstruction be avoided?
Gentle intubation
Head position
Avoid overextension neck
Gentle extubation
Checking airflow immediately on extubation
Careful positioning of horse in recovery box
Diligent monitoring of horse during recovery
How can an airway obstruction be dealt with?
Horse may require re-anaesthesitisation
Have to wait for horse to become hypoxic and fall down
May have to reintubate or if not an emergency tracheostomy may be required
Steroids for inflammation
Any indication of pulmonary oedema with any froth in the airways etc= use furosemide
What factors can influence post-anaesthetic colic?
Stress, transport, anaesthetic/analgesics, surgery, feeding or lack of
Describe some complications with IV cannula complications
Infections leading to thombrophlebitis- leading to jugular obstruction
Can kink or obstruct
Can come off in recovery- if catheter is pointing towards head- risk of haemorrhage, if pointing towards thoracici inlet- risk of air embolous
What are the requirements of a recovery box environment?
Quiet Controllable lighting Padded and non slip Cleanable No corners Facilities for observation Close to theatre Escape route for staff Available oxygen Scavenging Wall rings and ceiling hooks
Describe assisted recovery
Usually combined with operative sedation
Topical phenylephrine or nasal tube placed
Soft tight fitting headcollar with tail plaited and tied
Oxygen supplemented at 15l/min, demand valve used to ventilate until spontaneous breathing begins
Endotracheal tube usually removed
Eyes covered with soft towel/ ears plugged with cotton wool
Describe an ideal head and tail rope recovery
Continue observations of respiratory system, eye signs, musculoskeletal
2 people per rope
Move to sternal/ stand ropes kept taught to guide and support horse
Assess safety of situation before approaching horse
Ensure airway is patent, check for residual anaesthetic effects and check over for signs of injury
Release from ropes and allow time before moving
Describe post recovery
Allow access to water
Withhold feed for 3-4hrs then reintroduce slowly
Check later for signs of lameness, myopathy and pain
Motor urine and faecal output overnight
Colic check for 24hrs after anaesthetic
