Equine Anaesthesia- Recovery

Question 1

What are examples of recovery complications?

Answer 1

• colic
• airway obstruction
• trauma- orthopaedic, soft tissue
• neuropathy- central and peripheral
• catheter problems
• myopathy (EPAM)

Question 2

Describe equine post-anaesthetic myopathy

Answer 2

• 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

Question 3

Why does myopathy develop?

Answer 3

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

Question 4

How can EPAM be treated?

Answer 4

NSAIDs and opiods

Fluids can help to reduce any potential damage of myoglobin area

Question 5

How can EPAM be prevented?

Answer 5

Minimise duration of anaesthesia
Position and pad well- support the legs of patient with air bags
Maintain 02 delivery to muscles

Question 6

Describe peripheral neuropathies (neuropraxis)

Answer 6

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

Question 7

Describe spinal cord myelomalacia

Answer 7

Rare
More common in young male horses
More common after dorsal recumebency
No apparent problems during anaesthesia
Aetiology unclear

Question 8

Define stridor

Answer 8

inspiratory

high pitched noise

Question 9

Define stertor

Answer 9

expiratory

heavy snoring sound

Question 10

Define paradoxical ventilation

Answer 10

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

Question 11

What can be seen as airway obstruction?

Answer 11

Nostril flaring
Paradoxical ventilation
Absence of airflow at nostril
Stridor or stertor

Question 12

What can be causes of airway obstruction?

Answer 12

Nose in corner of box
Nasal congestion
Laryngeal paralysis
Airway swelling

Question 13

How can airway obstruction be avoided?

Answer 13

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

Question 14

How can an airway obstruction be dealt with?

Answer 14

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

Question 15

What factors can influence post-anaesthetic colic?

Answer 15

Stress, transport, anaesthetic/analgesics, surgery, feeding or lack of

Question 16

Describe some complications with IV cannula complications

Answer 16

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

Question 17

What are the requirements of a recovery box environment?

Answer 17

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

Question 18

Describe assisted recovery

Answer 18

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

Question 19

Describe an ideal head and tail rope recovery

Answer 19

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

Question 20

Describe post recovery

Answer 20

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