Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Anaesthesia > Equine Anaesthesia > Flashcards

Equine Anaesthesia Flashcards

1
Q

What are the three types of anaesthesia in the horse?

A

Standing - sedative, plus local analgesia

Short term total IV anaesthesia (TIVA) - e.g castration. Should still have o2 nearby

Prolonged - Inhalation or TIVA need o2 and ability to ventilate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

When should you be aware of when a horse is sedated?

A

They still have reactions - can kick etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What drugs are contraindicated in standing adult horses?

A

Anything that causes muscle weakness e.g. benzodiazepines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How can ACP be administered in the horse?

A

IV
IM
Oral gel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the advantages of using ACP in the horse?

A

Mood changing - anxiolytic - good for shoeing and clipping

Limited apparent sedation, unless opioids are given

When used as premed halves anaesthesia risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the contraindications of ACP in the horse?

A

Hypovolaemia
Stallions
Care re: abuse in competition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How can alpha 2 agonists be administered in the horse? What can they be given with?

A

Licensed for horses - can all be given IV.

Can be used for prolonged sedation

Can be given with opiods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the three alpha 2 agonists commonly used in the horse?

A

Xylazine
Detomidine
Romifidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the side effects of alpha 2 agonists in the horse?

A 
Bradycardia - decreased CO
Initial hypertension then BP returns to normal
Increased urine output
Hyperglycaemia
Gut stasis 
Ecbolic (uterine contractions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why might an opioid be given with an alpha 2 agonist in the horse? Which one is commonly used?

A

Prevents response to touvh
Only small doses of opioid are given - no analgesia
Often butorphanol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What can be given as analgesia in the horse?

A

Local blocks

Epidural analgesia

NSAIDs (reducing swelling is good, especially in the limbs but care as overdose -> gut toxicity diarrhoea due to colonic ulceration)

Opioids

Alpha 2 agonsits

Lidocaine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How would you prepare for anaesthesia in the horse?

A
  1. Pre-anaesthetic exam
  2. Starvation for 12 hrs no water for 2
  3. Remove shoes
  4. Premedication - ACP unless specific reason not to e.g. hypovolaemia
  5. Catheterisation
  6. ABs/anti-ten
  7. Wash out mouth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is included in the premedication of horses?

A

Almost always ACP
Sometimes give alpha 2 agonists - more commonly used as co-induction

Pre-emptive analgesia
NSAIDs
Opioids
Local

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the problems associated with IV in the horse/

A
  1. Intracarotid injection
    Drugs have very rapid effect - often horse goes down on the end of the needle
  2. Air embolism
    Especially is catheters are going downwards
  3. Infection
  4. Jugular thrombosis
    Drug irritation
    Thrombin problems with endotoxaemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where should a catheter be place in a horse for surgery?

A

Jugular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the three ways of controlling a horse during induction?

A

Free fall
Gate
Tilting table

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the two IV induction combinations in horses?

A
  1. Ketamine based
    Alpha 2/Ketamine +/- benzodiazepine
  2. Hyponotic based
    Alpha 2 and/or ACP plus thipental
    Propofol or alfaxalone have been used but currently too expensive to be practical
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What should be given before ketamine in horse anaesthesia?

A

Alpha 2 agonist or other sedative

Horse must be well sedated before giving ketamine as it causes excitement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How is ET performed in the horse?

A

Blind
Very easy as little laryngeal reflex
Make sure that cuff is intact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How should anaesthesia of horses be maintained?

A

Inhalation (if >1hr)
TIVA
PIVA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Give examples of problems that horses can have during anaesthesia

A

Horses not designed for prolonged recumbency
Maintenance of anaesthesia and adequate provision of analgesia
Hypotension
Hypoxia
Hypercapnia
Cardiac arrest
Post-op complications - myopathy, neuropathy, spinal damage

22
Q

Which inhalation agents are used in horses?

A

Isoflurane - only one licensed in horses

Sevoflurane

Desflurane

23
Q

What breathing system is used in horses?

A

Circle - closed system or can’t give enough oxygen

IPPV very commonly needed so ventilator very helpful

24
Q

What should be monitored for a horse anaesthetised with a volatile agent?

A

Direct arterial BP - absolute
ECG
Capnography - ideal
Blood gas analysis
Pulse oximetry (although usually don’t work as horse too thick)
End tidal agent monitor (often included in capnography)

25
What general nursing care should be performed to the anaesthetised horse?
Eye lubrication Support limbs Optimise ventilation Catheterise bladder
26
How should a horse be positioned in a later position in anaesthesia? Why?
Everything padded Under front leg drawn forwards and under hind back Upper limbs should be supported Head should be slightly raised Can get myopathy due to weight - must maintain venous return and blood to the muscles
27
How should a horse be positioned in dorsal when anaesthetised?
Soft padding Do not extend hind legs - if stifle locks for a long time results in muscle and nerve damage Head up but not stretch out - can get laryngeal paralysis
28
How can you stabilise volatile anaesthetic in the horse?
Can be difficult - can wake up without much warning IV agent should be kept to hand preferable thiopental - ketamine takes too long
29
What can be used for intraop analgesia in the horse?
Difficult to assess need as often no CV changes Local blocks More inhalation Top up - small doses of ketamine or thipental PIVA - Ketamine infusions - More alpha 2 agonists - Bolus doses or infusions - Lidocaine infusions - Opioids eith alpha 2
30
Why can hypotension occur in the anaesthetised horse?
Myocardial depression and low heart rate (=> low CO) Vasodilation (isoflurane worse) - however when vasoconstrict, high TPR means greater cardiac work, so further fall in CO and poor peripheral perfusion
31
What is the result of hypotension in the anaesthetised horse?
Cardiac arrest if severe | Myopathy is moderate and prolonged
32
How can hypotension be treated in the anaesthetised horse?
Improve CO - Positive inotropes (e.g. dobutamine, ephidrine) - Reduce volatile agent - Give fluids Do not give drugs to vasoconstrict unless hypotension is v v severe (increases blood pressure but not flow)
33
Why are horses prone to hypoxaemia during anaesthesia?
Recumbency Hypoventilation Leads to atelectasis and V/Q mismatch
34
How can hypoxaemia be treated during inhalational anaesthesia in the horse?
IPPV using 100% oxygen - doesn't always work Bronchodilator (salbutamol) Improve CO - improves o2 delivery
35
What causes hypercapnia in the anaesthetised horse? How should it be treated?
Possible response to hypoxia - Hypoxic horses usually breathe well and are not hypercapnic IPPV gets rid of excess CO2 but removed the advantangeous effects of moderate hypercapnia on circulation (high CO2 best CV stimulant)
36
What is the problem with detection of cardiac arrest caused by anaesthesia in the horse?
Can be detected with electronic monitoring Goes on breathing for a long time after heart stops Cerebral hypoxia = looks like waking up but actually dying
37
What are the possible reasons for a cardiac arrest caused by anaesthesia in the horse?
High vagal tone | Severe hypotension means heart is underperfused
38
How can you treat intra-anaesthesia cardiac arrest in the horse?
Switch off volatile agent IPPV with 100% O2 External cardiac massage When have obtained a circulation, continue massage and give adrenaline/atropine IV
39
What is PIVA? | Which drugs can be used in the horse?
Partial IV anaesthesia Infusions of analgesic drugs to reduce inhalation agent Lidocaine, alpha 2, midazolam and ketamine are used All reduce amount of iso needed so better BP Only ketamine gives better CO than higher doses of iso alone
40
What can be used for induction of field anaesthesia in horses? What are the pros of this?
Alpha 2, ketamine (+/- diazepam) ``` Good induction Minimal CV depression High safety margin Add local analgesia to prolong effect Excellent recovery (esp if no benzo) ```
41
How can field anaesthesia be maintained in the horse? Pros?
Triple drip TIVA Guiaphenesin, alpha 2 agonist and ketamine - Gives stable anaesthesia for short procedures (ideally <1hr) - Best used after no guaiphensin at induction
42
What can be used to prolong anaesthesia beyond a trip drip in horses?
1. Reversible anaesthesia - Benzo bases - Opioid base 3. Propofol based - Pro and ket - Pro and alpha 2 - Pro/alpha/ket 3. Alfaxalone
43
What is immobilon?
Etorphine plus ACP Very potent Licensed for horses IV
44
Give examples of potential problems in horse anaesthesia recovery...
Airway obstruction Hypoxia Physical damage
45
What should be done during equine anaesthesia recovery?
1. Maintain airway - Nasal swelling - reduced by phenylephrine nasal drops 2. Give oxygen 3. Sedate 4. Assist recovery 5. Analgesia and empty bladder
46
What are the three main methods of recovery in horses?
1. Free recovery 2. Rope assisted 3. Pool
47
Give examples of problems showing during or after equine anaesthesia recovery...
1. Injury (corneal abrasion, fractures) 2. Nasal oedema and resp obstruction 3. Myopathy 4. Neurapraxia and neuropathy 5. Pulmonary oedema 6. Myelomalacia
48
What is myopathy in horse anaesthesia?
Re-perfusion injury due to lack of perfusion of muscle during surgery - very painful
49
How can myopathy be avoided in equine anaesthesia?
Short surgery Careful positioning and padding Adequate blood pressure Good cardiac output
50
Which animals can spinal cord malacia be seen in?
Young cobs - happens when on back for a long time

Anaesthesia (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions