Term
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Definition
| – pain with no identifiable cause |
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Term
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Definition
| pain that occurs after injury |
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Definition
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Definition
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Term
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Definition
| giving analgesics before sx, decreases analgesic requirements and minimizes CNS sensitization |
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Definition
| – the protective sensation of pain that occurs when there is no or minimal tissue injury |
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Term
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Definition
| detection by the nervous system of the potential for or the actual occurrence of tissue injury |
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Term
| What is the process by which thermal, mechanical, or chemical noxious stimuli are converted into electrical signals? |
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Definition
Step 1 of the pain pathway
Nociception, the pain pathway, consists of 4 main steps
1. transduction - the transformation of thermal, mechanical, or chemical noxious stimuli into electrical signals called action potentials by peripheral A-delta and C nerve fibers
2. transmission – the sensory impulses are conducted to the spinal cord
3. Modulation – in the spinal cord, where the A-delta and C fibers terminate, the impulses can be altered by other neurons, which either amplify or suppress them
4. perception – the impulses are transmitted to the brain where they are processed and recognized |
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Term
| What is the process in the spinal cord by pain impulses can be altered by neurons that either suppress or amplify nerve impulses? |
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Definition
Nociception, the pain pathway, consists of 4 main steps
Step 3. Modulation – in the spinal cord, where the A-delta and C fibers terminate, the impulses can be altered by other neurons, which either amplify or suppress them |
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Term
| Know and understand the processes for administering multimodal analgesic therapy. |
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Definition
| At each level of the pain pathway different receptors are involved in the nociceptive process, allowing the choice of drugs that target a specific receptor. A goal of pain mgmt, esp severe pain, is to target 2 or more receptors. Multimodal therapy is preferable to using a single analgesic because lower dosages can be used, which decreases adverse effects and improves safety |
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Term
| Where in the pain pathway does secondary sensitization or windup occur? |
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Definition
| Centrally, in the spinal cord, neurons that are stimulated by constant nociceptive input from the periphery become hyperexcitable and sensitive to low-intensity stimuli that would not normally elicit a pain response. Called central nervous system hypersensitivity “wind-up” |
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Term
| Know the specific drug combinations that will produce multimodal analgesic therapy |
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Definition
Transduction: NSAIDs, opiods, local anesthetics, corticosteroids
Transmission: local anesthetics, alpha2-agonists
Modulation: local anes, NSAIDs, opiods, alpha2-agonists, ketamine, tricylic antidepressants, anticonvulsants
Perception: Opiods, sedatives, general anesthetics |
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Term
| Know the drug combinations that would target several different pain receptor mechanisms. |
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Definition
| NSAIDs, opiods, local anesthetics |
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Term
| Know the potential side effects of opioid administration in cats and dogs. |
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Definition
Adverse effects on cardiovascular and resp system
excessive sedation
panting
increased sensitivity to sound
urinary retention
If used as solo agents at high doses may induce excitement in pts that are awake, particularly cats/horses
GI effects characterized by initial increase in GI activity, incl nausea/V and defecation, followed by a relative slowdown of the GI tract w/ the development of ileus, colic in horses and constipation |
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Term
| Know the mechanism of action of nonsteroidal antiinflammatory drugs. |
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Definition
Inhibition of prostaglandin synthesis
PGs are a group of extremely potent chemicals that are normally present in all body tissues and are involved in the mediation of pain and inflammation following tissue injury. PGs are also responsible for a variety of homeostatic processes, incl maint of normal GI, repro, renal and ophthalmologic fxn. Most NSAIDs prevent pain and inflam by inactivating the enzyme cyclooxygenase (COX), which catalyses one of the steps in the production of PGs.
Two important COX isoenzymes that vary in importance from tissue to tissue.
COX-1 – normally present (or constitutive) in most tissues
COX-2 – constitutive in some, such as kidney, repro organs, and eyes. Inducible (ie not normally present but is produced under certain circumstances) esp during tissue damage and inflammation.
Inhibition of both COX isoenzymes, but particularly COX-2, has been linked to analgesic effects.
Most NSAIDs inhibit both, but the ratio varies.
COX-2 selective drugs (carprofen, meloxicam, deracoxib) or specific (firocoxib) are less likely to interfere w/ intestinal barrier fxn and prduce GI ulceration; however all NSAIDs have the potential to be nephrotoxic |
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Term
| Know the potential side effects of NSAID administration |
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Definition
Significant potential for toxicity in sm animal pts
Acetaminophen highly toxic to cats
Many NSAIDs safe in healthy animals but may have serious toxic effects in dehydrated or hypotensive animals.
Adverse effects due to fact that they reduce not only the production of the PGs that mediate pain, inflammation and fever, but also those that are beneficial
GI ulceration (due to the beneficial PG prostacyclin which helps reduce gastric acid secretion and promote mucous production being adversely affected)
- meloxicam, carprofen, etodolac have less ulcergenic activity in dogs and are preferred for long-term use
renal toxicity
impaired platelet aggregation which can lead to prolonged bleeding
liver damage (carprofen) Hepatocellular toxicosis is most common in Labs and may be evident as soon as two wks after tx
may antagonize the action of several drugs commonly prescribed for cardiac dz and hypertension incl some ACE inhibitors and some diuretics |
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Term
| What would, and would not, be a possible consequence of untreated pain in a patient. |
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Definition
- pain produces a catabolic state which may lead to wasting
- suppressed immune response, predisposing to infxn and increasing hosp time and cost
- promotes inflammation, delaying wound healing
- anes risk increased because higher doses of anes drugs are req’d
- causes pt suffering, which is also stressful for owners |
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Term
| Know and be able to identify pain related physiological changes in patients |
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Definition
Cardiovascular:
- hypertension
- tachycardia, tachyarrhythmia
- peripheral vasoconstriction (pale mm)
Respiratory:
- Tachypnea
- Shallow breathing (abdo or thoracic guarding)
- Exaggerated abdo component
- Panting (dogs)
- Open-mouth breathing (cats)
Opthalmic
- mydriasis |
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Term
| Be able to identify which pharmaceuticals are classified as opioids. |
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Definition
- morphine
- hydromorphone
- oxymorphone
- methadone
- meperidine
- fentanyl
- buprenorphine
- butorphanol
- pentazocine |
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Term
| Be able to identify which pharmaceuticals are classified as alpha-2 adrenoceptor agonists. |
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Definition
- xylazine
- dexmedetomidine
- detomidine
- romifidine |
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Term
| . Be able to identify which pharmaceuticals are classified as COX-1 selective NSAIDs |
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Definition
- Aspirin
- Acetaminophen
- flunixin meglumine
- ketoprofen
- ketorolac
- phenylbutazone
- piroxicam |
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Term
| . Be able to identify which pharmaceuticals are classified as nonopiate mu-receptor analgesics. |
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Definition
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Term
| Which drug is a weak analgesic and sedative that can be used as a reversal agent for opioid agonists? (It is a kappa agonist and a mu antagonist.) |
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Definition
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Term
| . All NSAIDs are metabolized and conjugated by which organ, and then eliminated by which two systems? |
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Definition
| All NSAIDs are eliminated by metabolism and conjugation w/in the liver, followed by renal or biliary elimination. |
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Term
| Know the advantages, and possible disadvantages, of NSAIDs over opioids for analgesia |
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Definition
Advantages:
- Not subject to the storage, handling, and record-keeping regulations that govern narcotics
- Little abuse potential
- Effective when given orally
- negligible effect on cardiovascular and resp systems
- do not depress the CNS and therefore lack the sedative effect of opiods
- provide effective and safe relief for mild to moderate pain
- for some applications, analgesic effect appears to be superior to that of butorphanol or meperidine |
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Term
| Which drug(s) may be given concurrently with NSAIDs to form a proteinaceous complex to help protect the gastric mucosa? |
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Definition
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Term
| Which opioid is commonly used in a transdermal patch to provide analgesia at home for long periods of time? |
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Definition
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Term
| What may be the only method of analgesic delivery that is effective in constant, unremitting pain in some patients? |
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Definition
| CRIs of opioids may be the only method of analgesic delivery that is effective in constant, unremitting pain in some patients. |
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Term
| Know the properties and of using morphine epidurally for pain relief. |
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Definition
- Most commonly used epidural drug (preservative free to avoid neurotoxic preservatives)
- offers more profound analgesia for a longer time than when given by IM or SC inj
- excellent post-op pain
- direct, long-lasting effect on pain receptors in spinal cord but does not reach high concentrations in bloodstream due to low fat solubility. Adverse effects are therefore rare
- for preemptive analgesia for post-op pain, should be given after induction but before procedure. (significantly less effective when given in post-op period)
- Dose: 0.1 mg/kg in dogs and 0.05 to 0.1 mg/kg in cat,s diluted w/ sterile saline to a vol of 0.3 ml/kg.
- recommended max volume inj is 0.45 ml/kg
- onset of analgesia 20 – 60 min
- duration 6 – 24 hrs
- can use epidural catheter to instill morphine longer (hours – days) |
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Term
| Know what would be, and not be, a contraindication for the use of an epidural in a patient. |
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Definition
- septicemia
- local infxns in the lumbosacral space
- bleeding disorders
- spinal trauma
- neurologic dz of the spinal cord |
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Term
| . From the standpoint of analgesia, what are the major advantages of opioid agents? |
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Definition
- often included in injectable premeds
- when used preemptively they diminish windup
- at higher doses, opioids can be used in combo w/ tranq to induce a state of potent sedation (neuroleptanalgesia) that offers considerable analgesia throughout the sx period and for some time thereafter.
- can be used alone or in combo w/ other agents to provide post-op pain control |
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Term
| Which opioid(s) can be used to reverse the sedation and respiratory depression induced by mu agonist opioids while maintaining some analgesic effect? |
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Definition
Butorphanol – will also partially reverse the analgesic effect of these drugs
Nalbuphine? |
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Term
| . What are the common signs of pain in patients? |
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Definition
Cardiovascular:
- hypertension
- tachycardia, tachyarrhythmia
- peripheral vasoconstriction (pale mm)
Respiratory:
- Tachypnea
- Shallow breathing (abdo or thoracic guarding)
- Exaggerated abdo component
- Panting (dogs)
- Open-mouth breathing (cats)
Opthalmic
- mydriasis |
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Term
| What are the possible side effects of NSAIDs? |
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Definition
Significant potential for toxicity in sm animal pts
Acetaminophen highly toxic to cats
Many NSAIDs safe in healthy animals but may have serious toxic effects in dehydrated or hypotensive animals.
Adverse effects due to fact that they reduce not only the production of the PGs that mediate pain, inflammation and fever, but also those that are beneficial
GI ulceration (due to the beneficial PG prostacyclin which helps reduce gastric acid secretion and promote mucous production being adversely affected)
- meloxicam, carprofen, etodolac have less ulcergenic activity in dogs and are preferred for long-term use
renal toxicity
impaired platelet aggregation which can lead to prolonged bleeding
liver damage (carprofen) Hepatocellular toxicosis is most common in Labs and may be evident as soon as two wks after tx
may antagonize the action of several drugs commonly prescribed for cardiac dz and hypertension incl some ACE inhibitors and some diuretics |
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Term
| . Know the signs, symptoms, and treatments for aural hematomas. |
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Definition
Incision drainage procedure (only one of many tx options)
-used to eliminate the dead space between the layers of cartilage until scar tissue can form
- s-shaped or straight incision made ver the hemaatoma
- fibrin/blood clots removed, area lavaged
- several vertical mattress sutures places on concave surface of the ear around the incision to avoid pocket formation
- incision open for drainage |
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Term
| Know the signs, symptoms, and treatments for chronic otitis. |
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Definition
Lateral ear canal resection – allows drainage of the ear canal while affording ventilation of the canal
- sx improves the condition but not a cure |
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Term
| Know the signs, symptoms, and treatments for entropions. |
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Definition
Indications:
- to alleviate ocular irritation caused by the eyelid or by the facial hairs adjacent to it
Clinical signs:
- lacrimation
- blepharospasm (squinting, blinking)
- photophobia
- enophthalmos (pulling back of the eye and a secondary, raised third eyelid)
- conjunctivitis
- keratitis (inflammation of the cornea) w/ or w/o corneal ulceration
- self-trauma
Sx options:
Eyelid tacking
- temp fix – young pups up to 16 – 20 wks
Holtz-Celsus procedure |
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Term
| What specialized surgical instruments are needed for entropion repairs? |
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Definition
- half-curved tissue forceps – used for handling eyelid and conjunctival tissue
- Chalazion forceps – provide tissue stabilization and hemostasis
- Jaeger lid plate – flat, curved ends that are placed under the eyelid to provide a firm surface when making an incision
- tenotomy scissors – short, blunt, narrowed tips for dividing and dissecting the muscles and tendons of the eye during recession and resection for strabismus sx
- needle holders – for handling delicate suture needles. Fine needles are held by jaws attached to spring-loaded handles that catch or release with gentle pressure. |
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Term
| . Know the signs, symptoms, and treatments for eyelid masses or tumors. |
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Definition
K9 Eyelid masses usually benign, but should be examined histologically
Most common – meibomian (sebaceous) adenoma
Fel eyelid masses usually neoplastic
Most common – squamous cell carcinoma
Mass should be removed if:
- the mass becomes too large
- there is concern about malignancy
- corneal or conjunctival irritation is present
- the pt is traumatizing the mass, w/ or w/o bleeding
- sometimes for cosmetic reasons
Sx options:
Wedge resection |
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Term
| After an eyelid mass removal, what would be the most appropriate steps to take, or things to do? |
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Definition
| Biopsy and submit for histopathology to confirm dx |
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Term
| Know the signs, symptoms, and treatments for inflammation of the gland of the third eyelid. |
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Definition
For years, removal was done, now sx repositioning is done
Morgan pocket technique |
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Term
| Know the proper process and steps for dealing with acute fractures. |
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Definition
- Not usually life-threatening unless skull/spine or lg blood loss due to long-bone fx
- nonelective but not life threatening are open fx or open dislocation
these cases need to be fully evaluated and pt stabilized (open airway, controlled bleeding, stable vital signs, and managed pain) before further eval or sx can occur.
- elective ortho sx cases may incl: cranial cruciate or anterior cruciate ligament repair, medial or lateral patellar luxation, CHD, or osteochondritis dissecans
- pts w/ fx can be assumed to be in severe pain and need strong analgesics, it is the RVT’s job to make sure the pt gets adequate pain mgmt
- fx should be immobilized and bandaged
external coaptation (application of external appliance such as a splint or cast) is important to reduce further disruption or damage to the fx or fragments and the surrounding soft tissue and to prevent further blood loss.
- stabilization greatly enhances pain mgmt and the animal’s comfort level
43. Know the proper processes and steps for bandage, cast, and splint care. |
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