Local, Regional and Spinal Anesthesia

Question 1

Why do we use local, regional or spinal anesthesia in food animal medicine?

Answer 1

Cheaper and less needed
-Get drug right where you need it faster
-Help mitigate pain
-Prevents us from having to lay them down for surgery/prevent complications

Question 2

Why are ruminants’ poor candidates for general anesthesia?

Answer 2

Regurgitation, bloat, muscle damage

Question 3

What are some drugs used for local anesthetics?

Answer 3

Lidocaine hydrochloride, mepivacaine, bupivacaine

Question 4

What is the toxic dose of lidocaine in cattle? Small ruminants?

Answer 4

Cattle: 10mg/kg (300ml)
Small Ruminant: 5mg/kg (4.5ml)

Question 5

How long is the duration of lidocaine?

Answer 5

1-2hrs

Question 6

How can you increase the potency and duration of action of lidocaine?

Answer 6

Add epinephrine (NOT nreat the spine)

Question 7

What is the mode of action of lidocaine?

Answer 7

Block fast voltage gated na channels in neuronal cell membrane - nerve conduction is inhibited

Question 8

What type of blocks are used for a laparotomy? (DA, C-section, rumenotomy)

Answer 8

Line, inverted L, distal paravertebral, proximal paravertebral

Question 9

How is a line block used?

Answer 9

Block area of paralumbar fossa, SQ into muscle and peritoneum, delayed healing possible complication
18G 1 inch

Question 10

Describe the Inverted L block

Answer 10

Non-specific
behind 13th rib and ventral transverse processe of lumbar vertebrae
18g 1.5inch
Minimize incisional hematoma
150-200ml lidocaine
Stick many times

Question 11

Describer the Distal Paravertebral Block

Answer 11

Desensitize T13, L1, L2 (Palpate L1, L2, L3 and L4)
18G 1.5inch
Lidocaine dorsal and ventral to transverse process 10-20ml per site
60-120ml lidocaine

Question 12

Describe Proximal Paravertebral Block

Answer 12

T13, L1 and L2
18g 1.5inch
needle cranial edge L1, L2, L3
walk off cranial edge with 16g guide
6-10ml/site

Question 13

What is the caudal epidural used for and what does it block?

Answer 13

Dystocia, prolapse, embryo transfer and flush

Block S5 down

Goal space for needle - S5-C1 - tail down when place needle
18G 1.5inch
Move tail to see sleepy

Question 14

What is the technique called for caudal epidural?

Answer 14

hang and drop method (negative pressure in spinal cord sucks the drop in), then attach

Question 15

What does the caudal epidural desensitize?

Answer 15

S2, S3, S4, S5

Question 16

How much lidocaine goes in a caudal epidural?

Answer 16

Never more than 6-7ml (1ml/200lb)

Question 17

Lidocaine dose for cattle epidural

Answer 17

1ml/200lb

Question 18

What is the small ruminant epidural dose?

Answer 18

1ml/33lb

Question 19

Why use a high volume caudal epidural?

Answer 19

Abdominal, udder, UT, c-section, down,

Dose: 4-6mg/kg (up to 8)

Question 20

What does a lumbosacral epidural block?

Answer 20

For sedated animals - on ground - gets leg
- c-section SR
- use spinal needle
Wing of illeum land mark

Question 21

What is the retrobulbar block used for?

Answer 21

Enucleation
-18G spinal needle, bend to get around globe
15-20ml lidocaine each site

Question 22

What is the Peterson eye block?

Answer 22

Anesthetize skin and use 14G cannula, coronoid process
-15-20ml lidocaine

Question 23

Although it is more challengig why is the peterson eye block better?

Answer 23

Less edema and inflammation
-desentize occulomortor, trochlear, abducent and trigeminal
-zygomatic arch landmark

Question 24

What are the options for teat anesthesia and why do we use each?

Answer 24

Ring block - around base teat 5-10ml lidocaine

V-block

22-25G needle

Laceration or amputtion

Question 25

What is deep digital sepsis?

Answer 25

infeciton of foot that involves deeper structures DIJ and flexor tendon
4/5 lame

Question 26

What lesions can lead to deep digital sepsis?

Answer 26

Sole ulcer, white line disease, penatration wound, foot rot

Question 27

What is the presentation of deep digital sepsis?

Answer 27

Severe lameness, swollen and painful coronary band asymmetric , draining tract, weight loss

Question 28

What structures should be considered in deep digital sepsis?

Answer 28

P1, P2, P3, Distal sesamoids, deep digital flexor, suspensory, digital cushion

Question 29

What are treatment options for deep digital sepsis?

Answer 29

Euthanize, slaughter or surgery

Question 30

What changes do you see on x-ray with DDS?

Answer 30

Join space width change, subchondral bone lysis

Question 31

What are the surgical options for DIP?

Answer 31

1. Claw amputation (remove all bad - salvage)
2. Resection for DIP joint and necrotic tissues (more claw preservation for walking)

Question 32

Where can you amputate to toe?

Answer 32

Distal interphalangeal joint
Mid p2
proximal interphalangeal joint or proximal PIP

Sharp or ob wire

Question 33

What block do you use for distal limb amputation?

Answer 33

Bier Block

Question 34

How do you perform the bier block?

Answer 34

Tourniqute
clip and clean
use digital vessels or doral common digital vein - 25-30ml lidocaine per foot last 1-1.5 hr (butterfly)

Question 35

What are some key parts of amputation?

Answer 35

Debride all bad tissue, bandage well, antibiotic and pain meds (nuflour)

Question 36

How should you follow up with your distal limb amputation?

Answer 36

keep in small pasture 3-4 weeks, antibiotics, rechech bandage 5-7 day, 2nd light wrap
Keep block on 3-4 week