27. Epidural anaesthesia in cattle

Question 1

Anatomic considerations?

Answer 1

Anatomic considerations:

• Three membranes of the spinal cord: dura, arachnoid, pia mater
• Spinal cord ends at lumbar region: if epidural is used you can’t damage the spinal cord since it ends more

cranially than the actual injection site!

• Lateral openings (intervertebral foramina) between vertebral arches as windows for nerves leaving the

spinal cord

• After exit through the foramina the nerves divides into dorsal (sensory) and ventral (motoric) roots

Question 2

Indications?

Answer 2

Indications

• All surgeries posterior to the diaphragm

Question 3

Contraindications?

Answer 3

Contraindications

• Damaged: lumbar/sacral vertebrae, spinal cord, congenital deformities
• Inflammation: near to injection site, within vertebral canal
• Paresis/lameness of hindlimbs
• Very low bp or circulatory collapse

Question 4

Administration?

Answer 4

Administration

• Two techniques: Main difference is that sacrococcygeal

one uses injection btw

1. Low caudal epidural= Coccygo-coccygeal

• = between C1 (coccygeal 1) and C2 (coccygeal 2)
• Effect on: S3, S4, S5

2. High caudal epidural= Sacro-coccygeal

• = between S5 (last sacral) and C1 (first coccygeal)
• Effect on: S2, S3, S4, S5

Question 5

Materials?

Answer 5

Materials
• 10-ml plastic syringe
• 1.5-inch, 18-gauge, sterile needle
• 2 to 4 ml of 2.0% lidocaine
• Xylazine: Combination in the same syringe
o 2 to 4 ml of 2.0% lidocaine + xylazine (20 to 30 mg, max 1 ml? mistake in ppt?) anaesthesia
prolonged.
o excellent anaesthesia in a larger area
o mild sedation along with the anaesthesia

Question 6

Technique?

Answer 6

Technique

• Remove hair from the injection site + antiseptic solution
• Standing restraint
• The surgeon should stand behind the animal
• Move the tail up and down to locate the fossa (gaps btw the vertebrae’s) between the last sacral vertebra

and the first coccygeal vertebra= sacrococcygeal (preferred site since it has a larger gap than caudal one and

the last sacral vertebrae is not movable so easier to realize the gap! ) or between the first and second

coccygeal vertebrae

• Insert the needle wo syringe ventro-cranially at a 15-degree angle until the skin is penetrated
• Place a drop on the hub of the needle (hanging drop method)
• Anesthetic solution is drawn into the epidural space by negative pressure
• Attach a syringe to the needle and slowly inject
• Injection should go down freely (almost a gravity feeding

Question 7

Optimal dose?

Answer 7

Optimal dose:

• Patient’s size and condition
• Obesity, which may influence the amount of spinal canal adipose tissue