EQUINE NERVE BLOCKS Flashcards
When do you use nerve blocks
Help localise the site of pain and injury
Desensitise areas different areas of the distal limb depending on where it is performed
What does a nerve block involve
Injection of a small amount of local anaesthetic around the peripheral nerves of the distal limb .
Describe some contradictions of carrying out nerve blocks
- animals with a suspected fracture or other catastrophic injury
- animals with infections around the injection site
- not being thoroughly clean the limb and use aseptic technique
Why do you never carry out a nerve block on an animal with a suspected fracture
Causing these animals to weight-bear can lead to complete disruption of the fracture
Why do you never perform a nerve block on an animal with an infection around the injection site
Injecting through infected tissue will inoculate the infection into deeper tissue
Why do you never perform a nerve block when you can’t clean the limb
The nerve block sites are adjacent to synovial structures - causing an infection of these leads to expensive surgical treatment at best, euthanasia due to ongoing infection at worst
Which digital nerve block do you perform first
Palmar digital nerve block
Which part of the foot does the palmar digital nerve block desensitise
This block desensitises the caudal 1/3rd of the foot and sole, including the navicular structures, heel bulbs, etc.
What are the key structures that lie close to the palmar digital nerve block.
The pastern joint
DDFT
Where are the palmar digital nerves found
Found on the medial and lateral borders of the DDFT
How should you check you’re not in a blood vessel
Pull back the syringe
If blood enters then you know that your in a vessel
What nerve block should be carried out second if the firs shows no change
Abaxial sesamoid nerve block
Where do you perform the abaxial sesamoid nerve block
The neuromuscular bundles lie on the abaxial surface of the medial and lateral proximal sesamoid bones
Describe how local anaesthetic should be injected when performing a nerve block
Inject the medial nerve first
Insert the needle under the skin in a proximal to distal direction.
If you cannot inject easily, reposition the needle
Repeat on the lateral aspect of the limb
Which structures desensitise after an abaxial sesamoid nerve block
Caudal aspect of the fetlock joint
All the structures of the pastern and foot
