34 Equine Pain Management

1. Adaptive

2. Maladaptive

3. Nociceptive

4. Inflammatory

5. Neuropathic

What are the types of pain in horses?

Adaptive pain

Which pain protects horses against hostile environments, a necessary part of life?

Maladaptive pain

Which pain results from disease or trauma, which we want to GET RID OF when treating pain?

a. nociceptive pain

Which type of pain occurs from high threshold A-delta and C fibers, serving as an alarm system for the body against noxious stimuli?

a. nociceptive pain

b. inflammatory pain

c. neuropathic pain

b. inflammatory pain

Which type of pain occurs from high AND low threshold A-delta and C fibers, designed to help the damaged tissue heal, which can either be adaptive or maladaptive?

a. nociceptive pain

b. inflammatory pain

c. neuropathic pain

c. neuropathic pain

Which type of pain is a dysfunction of the nervous system, with no protective or reparative function, classified as maladaptive?

a. nociceptive pain

b. inflammatory pain

c. neuropathic pain

PREVENTION

What is the GOLDEN RULE for pain assessment?

Early identification

What increases treatment success when treating animals for pain?

CHANGE, NEVER withhold pain medication

By doing early pain detection, you can decide whether to change OR withhold pain medication?

1. ears back or lowered

2. eyes not engaged

3. "grimace" face or tension of facial muscles

4. contraction of muscle above eye

5. edge of muzzle and lips pressed together, flattened chin

6. excessive time laying down

7. rockback stance or change in leg position

What are some signs of pain in horses?

Forward

When horse's hooves are painful, they will place the painful foot, forward or back

Right

Is the right or left foot painful in this horse?

a. visual analog scale

What pain assessment tool is reliable for laminitis, colic, and synovitis:

a. visual analog scale

b. composite pain score

c. horse grimace space/pain face

b. composite pain score

What pain assessment tool is reliable for abdominal and musculoskeletal pain:

a. visual analog scale

b. composite pain score

c. horse grimace space/pain face

c. horse grimace face/pain face

What pain assessment tool is used for post castration pain and laminitis:

a. visual analog scale

b. composite pain score

c. horse grimace face/pain face

High

Nociceptive pain has high OR low threshold, which will ultimately cause behavior response of motor withdrawal or defensive behavior in horses.

1. block neurotransmitters (local/regional nerve blocks)

2. alpha 2 agonists

3. opioids

4. general anesthesia

How do you treat nociceptive pain in horses?

a. local/regional nerve blocks

c. alpha 2 agonists

d. opioids

f. general anesthesia

Select which medications block nociceptive pain:

a. local/regional nerve blocks

b. beta blockers

c. alpha 2 agonists

d. opioids

e. gamma inhibitors

f. general anesthesia

b. alpha 2 agonists

Which medications to treat nociceptive pain activate inhibitory neurons:

a. local nerve blocks

b. alpha 2 agonists

c. opioids

c. opioids

Which medications treat nociceptive pain by decreasing a-delta and c fiber neurotransmitter release to decrease overall response of neurons:

a. local nerve blocks

b. alpha 2 agonists

c. opioids

Ketamine and tiletamine

Name two medications that change the pain pathway thru NMDA antagonist?

Allodynia

What is the term for non-noxious stimuli perceived as painful?

Hyperalgesia

What is the term for noxious stimuli that cause EXAGGERATED pain?

1. opioids

2. steroids

3. systemic lidocaine

4. pentafusion

5. NSAIDs

6. sodium channel blockers

What are some ways you can treat inflamamtory pain:

Steroids

What mechanism to treat inflammatory pain is CONTRAINDICATED if the animal has sepsis?

Morphine

You can use opioids to treat inflammatory pain in horses by either using it intraarticularly or IV regional limb perfusion. What opioid do we typically reach for for these procedures?

Systemic lidocaine

What treatment of inflammatory pain is commonly used to treat colic because it decreases inflammation associated with ischemia/reperfusion injury and decreases reflux associated with ileus?

a. lidocaine

b. morphine

c. ketamine

f. acepromazine

g. detomidine

Pentafusion can be used to treat animals with SEVERE inflammatory pain. Name the 5 medications used in this mixture:

a. lidocaine

b. morphine

c. ketamine

d. butorphanol

e. buprenorphine

f. acepromazine

g. detomidine

h. midazolam

FIRST: lidocaine

morphine

ketamine

acepromazine

LAST: detomidine

What ORDER should you do the pentafusion drugs in for SEVERE inflammatory pain:

detomidine

lidocaine

morphine

acepromazine

ketamine

Pentafusion

Lidocaine, morphine, ketamine, acepromazine, and detomidine combo for SEVERE inflammatory pain treatment is called WHAT?

75 mL/hr

About how fast should you run a pentafusion bag?

2% lidocaine add 500 mL to empty bag as base

For a 500 kg horse when you run a pentafusion bag, you should use how much Lidocaine?

b. phenylbutazone

c. flunixin meglumine

Which of the follow NSAIDs used for inflammatory pain treatment in horses are considered NONSPECIFIC:

a. firocoxib

b. phenylbutazone

c. flunixin meglumine

COX 2

Which COX is firocoxib specific for, making it best for use in foals and more protective of GI tract?

Renal, GI, coagulation

Name some side effects of using NSAIDs for inflammatory pain in horses?

TRUE

TRUE OR FALSE: neuropathic pain is ALWAYS maladaptive

Idiopathic headshaking, laminitis, arthritis, navicular syndrome

Name some common conditions that cause/indicate neuropathic pain in horses:

Neuropathic pain and hyperalgesia

Describe the types of pain typically involved with causing laminitis pain in horses?

Tramadol

Which medication is an opioid receptor agonist, decreasing TNF alpha for neuropathic pain, commonly used to treat horses with laminitis?

Ketamine

Tramadol, an opioid receptor agonist, is said to only have transient effects for treating horses with neuropathic pain. What can you combine it with to make it more effective?

c. gabapentin

What is the medication that is a GABA analog that acts on calcium channels:

a. ketamine

b. tramadol

c. gabapentin

d. morphine

Hindlimb pain: fractures, septic arthritis, myositis, lacterations

Why would you use epidural catheters to treat horses with pain? What injuries?

Preservative free morphine

What type of morphine is the ONLY KIND of morphine that can be used in epidural catheters, methylparaben preservative morphine OR preservative free morphine

Detomidine with morphine

When doing an epidural cathether, what medications are best to use in it?

Local anesthetic infusion/patches

What type of pain management can be used in horses to slowly release local anesthetic, lasting about 24 hours, where a catheter is placed intraarticuarly or adjacent to a nerve?

The drug is highly regulated and can be abused

Fentanyl patches are VERY effective for treating visceral pain in horses. Why are they not used very commonly?

WEIGHT MANAGEMENT

note: this is because adipose tissue is proinflammatory

What is the MANDATORY pain treatment that is the only thing that can truly help the horse long term, to decrease the load on the joints?

Acupuncture

Which additional pain management can be done on horses if you have done all the standards, basically just used for back pain because it does not have any effect on horses with palmar heel pain?

ONLY horses with back pain

Acupuncture only has effects on horses with back pain OR horses with palmar heel pain

sEH inhibitor (aka epoxide hydrolase inhibitors)

Which additional pain management can be done on horses if you have done all the standards, which acts on the arachidonic acid pathway to inhibit epoxide hydrolase?

FALSE

TRUE OR FALSE: Steroids are first choice pain management for laminitis

NSAIDs

What is typically the number one broad pain management medication you tend to reach for in horses with laminitis?

a. NSAIDs

b. gabapentin

e. acupuncture (+/-)

h. DMSO (+/-)

Which one of these treatments would you use in a case of MILD laminitis?

a. NSAIDs

b. gabapentin

c. tramadol with low dose ketamine

d. morphine

e. acupuncture

f. local anesthetic infusion/patches

g. intravenous pentafusion CRI

h. DMSO

a. NSAIDs

b. gabapentin

e. acupuncture (+/-)

h. DMSO (+/-)

You would ONLY DO ONE of these that you add to gaba, BOTH ARE NOT NECESSARY

c. tramadol with low dose ketamine

d. morphine

Which one of these treatments would you use in a case of MODERATE laminitis?

a. NSAIDs

b. gabapentin

c. tramadol with low dose ketamine

d. morphine

e. acupuncture

f. local anesthetic infusion/patches

g. intravenous pentafusion CRI

h. DMSO

a. NSAIDs

b. gabapentin

c. tramadol with low dose ketamine

d. morphine

e. acupuncture

f. local anesthetic infusion/patches

g. intravenous pentafusion CRI

h. DMSO

note: if you do the intravenous pentafusion, you do not do the tramadol and morphine on top of that, those medications would essentially just be in that pentafusion

Which one of these treatments would you use in a case of SEVERE laminitis?

a. NSAIDs

b. gabapentin

c. tramadol with low dose ketamine

d. morphine

e. acupuncture

f. local anesthetic infusion/patches

g. intravenous pentafusion CRI

h. DMSO