chapter 7 Flashcards
What is an essential part of every patient evaluation, regardless of presenting complaint?
a pain assessment
nocieption?
detection by the nervous system of the potential for or the actual occurrence of tissue injury
physiologic pain?
the protective sensation of pain that occurs when there is no or minimal tissue injury (pain you would feel that would warn you that you touched something sharp)
pathologic pa[n?
pain that occurs after tissue injury
Pathologic pain based on duration can be classified in two ways, what are they?
acute (hours) or chronic (days to years)
Pathologic pain is often classified based on the?
- mechanism
- origin
- severity of pain
The mechanism of pain can be?
- inflammation - (ie. after trauma or surgery)
- nerve injury (neuropathic)
- cancer
- idiopathic (no identifiable cause)
Pain can originate from?
organs - visceral pain (pleuritis or colic)
musculoskeletal system - somatic pain
Somatic pain can be divided into what?
superficial (skin)
deep (joint, muscles, bones)
transmitted by both A delta and C fibers
Some diseases or surgeries may result in more than one of these types of pain, what are they?
abdominal surgery has components of somatic pain (skin and abdominal wall incisions) and visceral pain (organ manipulation and surgery)
Pain severity is often classified as?
none, mild, moderate, or severe
Pain is defined as?
an unpleasant sensory or emotional experience associated with actual or potential tissue damage
Analgesia?
- the absence of the awareness of pain, achieved through the use of drugs or other modes of therapy
- the relief of pain without loss of consciousness
What are the principles of analgesia - ethical and medical reasons that vets and techs have to follow?
- must ensure analgesia is provided for every patient requiring it
- must recognize procedures likely to be painful
- must use techniques to minimize pain
- must monitor behavior and physiologic variables as potential indicators or pain
- technicians must bring animals requiring analgesia to the veterinarian’s attention
Untreated pain can negatively affect a patient’s?
- behavior
- physiology
- metabolis
- immune system
Chemicals released by inflammation or tissue damage?
prostaglandins, leukotrienes, bradykinin, proteolytic enzymes, histamine, potassium ions, serotonin
Nociception, or the pain pathway consists of four main steps, what are they?
- Transduction - transformation of noxious thermal, chemical, or mechanical stimuli into electrical signals called action potentials
- transmission - sensory impulses are conducted to the spinal cord
- modulation - in the spinal cord where fibers terminate, the impulses can be altered by other neurons, which either amplify or suppress them.
- perception - impulses are transmitted to the brain, where they are processed and recognized
What are action potentials?
electrical signals
Mutimodal therapy?
using several analgesic drugs, each with a different mechanism of action - results in lower doses, which increases safety
Sensory neurons located in the ?
peripheral tissue
Neurons in the spinal cord…?
convey and impulse to the brain
Neurons in the brain…?
convey the conscious sensation of pain
What are the 2 types of sensory neurons that transmit pain signals from peripheral tissues, spinal cord, and the brain?
- A delta fibers
2. C fibers
What do A delta fibers do?
- transmit sharp discrete pain signals
- pain is located to an exact spot
- large myelinated neurons conduct signals rapidly
What do C fibers do?
- transmit dull, aching or throbbing pain
- sensations cannot be exactly localized
- smaller, nonmyelinated neruons
- visceral pain - cramping, burning, gnawing
What is the difference between nociception and pain?
consciousness This means that patients under a general anesthetic do not perceive pain. However, nocieption occurs even when an animal is in a state of unconciousness.
What is primary hyperalgesia?
peripheral hypersensitivity
What is CNS hypersensitivity or windup?
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 repsonse
What is secondary hyperalgesia?
an area away from the initial injury
What are some behavioral responses to pain in dogs?
- vocalization, facial expression, body posture, guarding, self-mutilation, activity, attitude, appetite, urinary bowel habits, grooming, response to palpation
Body posture is one behavioral response in dogs, what are some examples?
- hunched, laterally recumbent
Guarding is one behavioral response in dogs, what are some examples?
- protecting wound, limping
Vocalization is one behavioral response in dogs, what are some examples?
groan, growl, whimper, whine
Facial expression is one behavioral response in dogs, what are some examples?
fixed stare, glazed appearance, ears back
Self-mutilation is one behavioral response in dogs, what are some examples?
- licking, chewing SX site or wound
Activity is one behavioral response in dogs, what are some examples?
- restless, restricted movement, trembling
Attitude is one behavioral response in dogs, what are some examples?
- increased aggression or fearfulness
Appetite - is one behavioral response in dogs, what are some examples?
decrease
Urinary bowel habits - is one behavioral response in dogs, what are some examples?
- increased urination, lapses in house training, urinary retention
grooming is one behavioral response in dogs, what are some examples?
- loss of sheen in hair coat
Response to palpation - is one behavioral response in dogs, what are some examples?
- protecting, biting, vocalization, withdrawing
Cats behavior responses to pain are?
- vocalization, facial expression, body posture, guarding, self-mutilation, activity, attitude, appetite, urinary bowel habits, grooming, response to palpation
Vocalization is one behavioral response in cats, what are some examples?
Groan, growl, purr
Facial expression is one behavioral response in cats, what are some examples?
furrowed brow, squinted eyes
Body posture is one behavioral response in cats, what are some examples?
sternal recumbency
Guarding is one behavioral response in cats, what are some examples?
protecting wound, limping
Self-mutilation is one behavioral response in cats, what are some examples?
licking and chewing SX site or wound
Actiivty is one behavioral response in cats, what are some examples?
restricted movement, circling
Urinary and Bowel habits is one behavioral response in cats, what are some examples?
failure to use the litter box
Grooming is one behavioral response in cats, what are some examples?
failure to groom, unkempt appearance
Response to palpation is one behavioral response in cats, what are some examples?
protecting, biting, scratching, vocalizing, withdrawing attempts to escape
Anthropomorphizing?
projecting human emotions onto animals
Preemptive analgesia?
providing analgesia before tissue injury - commonly achieved by adding an analgesic to the premedication before anesthetizing a patient for surgery
- prevents windup, which, through changes in the CNS from central sensitizaition, can lead to pain that last longer than anticipated
What are some examples of irritating or mildly painful procedures?
urine scald, clipper burns, IV or urinary catherization, distended bladder, superficial lacerations, eyelid procedures, dental prophylaxis
What are some examples of mildly to moderately painful procedures?
endoscopy with biopsy, dental extraction, arterial catheterization, aural hematoma, stabilized radial or tibial FX (fracture), castration, OHE, ear flush, cytotomy
What are some examples of moderately to severely painful procedures?
localized burns, corneal ulcerations, enucleation, thoracic or lumbar disk SX, Onychectomy, stabilized femoral or humeral FX, pelvic FX, mastectomy, cranial adominal SX, anal sacculectomy
What are some examples of severely painful procedures?
extensive burns, pancreatitis, total hip replacement, cervical disk SX, forelimb or hindlimb amputation, ear ablation, thoracotomy, laminectomy
What are some methods of pain control?
- endorphins -released by neurons when the body is traumatized or under stress - bind to opioid receptors - provide some analgesia
- acupuncture
- transcutaneous electric nerve stimulation
- massage therapy
- hot and cold therapy - for chronic and acute injuries
Define emergence delirium?
pain
more methods of pain control?
conscientious nursing care - keep animals clean and dry
- affording opportunities for defecation and urination bladder expression, catherterizaiton
- comfortable bedding
quiet surroundings
gentle reassurance
monitoring
Pain control in the surgical patient should be available at every stage of hospitalization and treatment, what are those stages?
- preanesthetic period
- surgical procedure
- immediate postoperative period
- remainder of the hospital stay
- patient’s return home
What are the options of delivering analgesic drugs?
IV, IM, SC, epidural, local infiltration
What are the methods (drugs) of delivering analgesic drugs?
opioids, NSAIDs, local anesthetic, combinations (multimodal therapy, balancec analgesia)
all governed by the severity and type of pain and the animal’s condition
What are the advantages of administering analgesics?
- before damage occurs
- before patient has an awareness of pain
- provides effective pain relief in recovering patients
- allows a reduction in the amount of general anesthesia during SX
Pharmacologic analgesia can be achieved through a variety of agents, what are they?
opioids, NSAIDs, alpha-2 agonists, ketamine, local anesthetics