Assessment 10 Pain - Types of Pain

135 terms by karscool Plus

Create a new folder

Advertisement Upgrade to remove ads

chapter 10 - Pain assessment: the fifth vital sign - types of pain and how it works

Neuroanatomic Pathway

pain is highly complex and subjective experience that originates from CNS or PNS or both; has nociceptors

Nociceptors

specialized nerve endings that detect painful sensations from periphery, transmit them to CNS

How do Nociceptors carry pain?

carry signal to 2 primary sensory (or afferent) fibers: A(gamma) and C fibers

A (gamma) fibers

myelinated, larger diameter so transmit pain signal rapidly to CNS; pain sensation is localized, short-term, sharp

C fibers

unmyelinated,small; transmit signal more slowly; "secondary" sensations are diffuse, aching, last longer after initial injury;

Where do primary afferent fibers enter spinal cord?

primary afferent fibers( A-delta and C fibers) terminate in the dorsal horn of the spinal cord unless blocked by a sodium channel inhibitor.

What happens when pain is poorly controlled?

over extended period, cells within dorsal horn become altered in size and function, this damage turns future pain signals into more exaggerated or hypersensitive processed signals

Nocioceptive Processing - Transduction

occurs when noxious stimulus in form of traumatic or chemical injury, burn, incision, or tumor takes place in periphery (includes skin, somatic and visceral structures)

Nocioceptive Processing - Transmission

pain impulse moves from leel of spinal cord to brain; at synaptic cleft, there are opiod receptors that can block pain signaling w/our own endogenous opiods or with exogenous opiods if they are adminstered

Nocioceptive Processing - Perception

indicates the conscious awareness of painful sensation; coritical structures like limbic system account for emotional response to pain, and somatosensory areas can characterized sensation; only when noxious stimuli are interpreted in higer cortical structures can this sensation be identified as "pain"

Nocioceptive Processing - Modulation

Neurons originating in the brainstem descend to the spinal cord and release substances(endogenous opioids) that inhibit nociceptive impulses.

Neuropathic Processing of Pain

pain that does not adhere to typical and rather predictable phases in nociceptive pain; implies abnormal processing of pain message from injury to nerve fibers; often perceived long after site of injury heals (can start 2-3 yrs later)

How do you test for Neuropathic Pain

pain is sustained on neurochemical level. Identify by electromyography and nerve-conduction studies

Abnormal processing of neuropathic pain

impules can be continued by PNS or CNS; proposed mechanism is that injury to peripheral neurons can result in spontaneous and repetitive firing of nerve fiber (almost seizure like) and sustained centrally in phenomenon known as neuronal 'wind-up'; in dorsal horn, neurons thought to be transformed into hyperexcitable state and minimal stimulus can ultimately spiral into much larger painful stimuli

Source of Pain

based on origin; viceral, deep somatic, cutaneous, mental, referred

Source of Pain - Viceral

pain originates from larger interior organs (kidney, stomach, intestine, gallbladder, pancreas); can stem from direct injury to organ or from stretching of organ from tumor, ischemia, distention, or severe contraction; pain impulse transmitted by ascending nerve fibers along w/nerves from autonomic NS; that is why visceral pain often presents along w/ autonomic responses (vomitin, nausea, pallor, diaphoresis)

Source of Pain - Deep Somatic Pain

comes from sources such as blood vessels, joints, tendons, muscles, and bone; injury may result from pressure, trauma, or ischemia

Source of Pain - Cutaneous

derived from skin surface and subcutaneous tissues; injury is superficial, w/sharp, burning sensation

Source of Pain - Mental

outdated and derogatory; psychogenic pain or psychogentic; linking pain to mental disorder negates pts pain report; lack of awareness and understanding of neuropathic pain may contribute to mislabeling

Source of Pain - Referred

pain felt at a particular site but originates from other location; both sites are innervated by same spinal nerve, and is difficutl for brain to differentiate point of origin; may originate from visceral or somatic structure; ex - inflamed appendix in right lower quad may have referred pain in periumbilical area

Types of Pain

can be classified by its duration into acute or chronic (persistent - carries less negative, malingering connotation) categories; duration provides information on possible underlying mechanisms and teatment decisions;

Types of Pain - Acute

short-term and self-limiting, often follows predictable trajectory, and dissipates after injury heals; serves a self-protective purpose; warns individual of actual or potential tissue damage; ex - surgery, trauma, kidney stones

Types of Pain - Acute Incident Pain

acute type that happens predictably when certain movements take place; ex - lower back upon standing or shoulder pain when arms raised

Types of Pain - Persistent (chronic)

diagnosed when pain continues for 6 mo or longer; can last 5, 15, 20 yrs or more; can be divided into malignant and nonmalignant; does not stop when injury heals and persists after predicted trajectory; many pts are not believed and often are labeled as malingers, attention seekers, drug seekers

Types of Pain - Chronic Malignant Pain

cancer-related; often parallels the pahtology created by tumer cells; is induced by tusse necrosis or stretching of organ by growing tumor; pain fluctuates w/disease

Types of Pain - Chronic Nonmalignant Pain

often associated w/musculoskeletal conditions such as lower back pain, arthritis, fibromyalgia

Types of Pain - Breakthrough Pain

pain that starts again or excalates before next scheduled analgesic dose; pain breaks through when is is expected to be controlled by pain meds

analgesic ceiling

increasing the dose beyond an upper limit provides no greater analgesia - true for nonopioid analgesics

Name 3 Characteristics common to Nonopioids

1. analgesic ceiling
2. do not produce tolerance or physical dependence
3. many available OTC
ex. acetaminophen, aspirin, NSAIDs

opioid-sparing effect

the phenomenon of nonopioids allowing for effective pain relief using lower opioid doses thereby causing fewer opioid side effects

Name 4 steps of the pain mechanism

1. Transduction
2. Trasmission
3. Perception
4. Modulation

breakthrough pain

is transient, moderate to severe pain that occurs in pts. whose pain is otherwise well controlled, Pain that occurs between doses of pain medication.

incident pain

a transient increase in pain that is caused by a specific activity or event that precipitates the pain (ex. dressing changes, movement, catherterization)

transduction

involves the conversion of a noxious mechanical, thermal, or chemical stimulus into an electrical signal called an action potential, caused by cell damag

noxious stimuli in pain

Harmful, stimuli that elicit tissue damage and activate nociceptors.
prostaglandins, bradykinin, serotonin, substance P, histamine

Name 5 substances that activate nociceptors and lead to the generation of action potentials at transduction stage

prostaglandins, bradykinin, serotonin, substance P, histamine

prostaglandins

An inflammatory mediator released when a cell is damaged. They cause vasodilation and stimulate inflammation.

bradykinin

substance released by damaged tissue that promotes inflammation

serotonin

neurotransmiter

What type of of opioid therapy should a cancer patient receive?

both long-acting and short-acting opioid

What can unrelieved pain lead to?

unrelieved pain is dangerous and can lead to many physical and psychological complications

Name an appropriate nonopiod analgesic fro mild pain

ibuprofen (Advil)
acetaminophen (Tylenol)

What type of myelation do C fibers have?

unmyelinated

How are nociceptors stimulated?

can be stimulated directly by trauma or injury or secondarily by chemical mediators that are released from site of tissue damage

dorsal horn

Crescent shaped projection of gray matter within the spinal cord where sensory neurons enter the spinal cord

Name the descending pathways neurotransmitters that impeded pain impulse producing an analgesic effect.

Descending pathways from brainstem to spinal cord produce 3rd set of neurotransmitters that slow down or impede pain impulse, producing analgesic effect: serotonin, norepinephrine, neurotensin, y-aminobutyric acid (GABA), and our own endogenous opiods: B-Endorphins, enkephalins, dynorphins

...

pain message is inhibited through modulation; our bodies have built-in system that will eventually slow down or stop the processing of a painful stimulus; if not, we would continue to experience pain from childhood injuries and beyond;

neurotensin

"relaxes the lower esophageal sphincter, blocks the release of stomach acid and pepsin, and regulates GI contraction and relaxation (pg. 58)"

Name our endogenous opioids

B-endorphins
enkephalins
dynorphins

dynorphins

endorphin that has the most potent analgesic effect

enkephalins

...

B-endorphins

natural opiates; painkillers (2)

ischemia

A condition in which the supply of blood to a part of the body is severely reduced

deep somatic

comes from sources such as the blood vessels, joints, tendons, muscles and bone. Injury may result from pressure, trauma or ischemia (local decrease in blood supply)

viceral

medical term for internal organs

Why does visceral pain present with automonic responses?

pain impulse transmitted by ascending nerve fibers along w/nerves from autonomic nervous system ---often result in vomiting, nausea, pallor diaphoresis

Name two types of chronic pain

malignant and non malignant

nursing care R/T pain meds opioids.these (including antagonists), ;

...

PCA

an IV delivery system or demand analgesia that is delivered when the patient decides a dose is needed. they receive a bolus infusion of analgesic. (morphine and hydromorphone commonly used)

epidurals

Advantage--Narcotic moves directly from epidural space into spinal fluid and binds with opiate receptors in the spinal cord to block pain perception. Lower doses are required
1) Catheter inserted by anesthesiologist
2) Inserted between L3 and L4 or L4 and L5.
a) If placed in subarachnoid space it is Intrathecal delivery
b) Doses are extremely small. (1/10 the epidural dose, 1/100 the IV dose)

Care for pt. wtih epidural.

Assessments
a) Assess for epidural catheter placement--
-1- Check site for swelling, redness, drainage (catheter dislodgement or abscess)
-2- Shooting pain down leg may be sign of nerve irritation from catheter.
-3- Cath may stay in place 1 - 5 days post-op.
-4- Position pt. in low or semi-Fowler's to keep level from rising up to chest- especially if an anesthetic is used
-5- Monitor same as for PCA plus sensation and movement to lower extremities

Care for pt. with PCA

*teach patient to self-administer before intensity is greater than the pt. desired pain intesity goal
*pt. cannot overdose

Name 3 Catergories of pain meds

nonopioids
opioids
adjunctive analgesic therapy

nursing care R/T pain meds including antagonists

...

Give examples of each type of pain.

...

Name 3 categroies of nonopioid analgesics more commonly used.

nonsalicylate (acetaminophen, Tylenol)
salicylate (aspirin)
NSAIDs (ibuprophen)

State nursing considerations for nonsalicyate.

*rectal suppository available
*doses above 4 g per day may cause gastric irritation and bleeding
*acute overdose: acute liver failure
*chronic overdose: liver toxicity
(nonopioid, acetaminophen, Tylenol)

State nursing considerations for salicyate.

*rectal suppository available
*Possibility of upper GI bleeding
* used more commonly in low doses as a cardioprotective measure than for its analgesic properties

Name 8 opioid agonists (effective for moderate to severe pain).

1. morphine
2. oxycodone
3. hydrocodone
4. codeine
5. methadone
6. hydromorphone (Dilaudid)
7. oxymorphone (Opana, Opana ER)
8. levorphanol (Levo-Dromoran)

How do opioids produce their effects?

by binding to receptors in the CNS which result in
1. inhibition of the transmission of nociceptive input from the periphery to the spinal cord
2. altered limbic system activity
3. activation of the descending inhibitory pathways that modulate transmission in the spinal cord

How are opioids catergorized?

by physiologic action (agonist or antagonist) and binding at specific opioid receptor (mu, kappa, delta)

Why are pure opioid agonists effective for moderate and severe pain?

potent, have no analgesic ceiling and can be administered through several routes

trigger point

a circumscribed hypersensitive area within a tight band of muscle, caused by acute or chronic muscle strain and can often be felt as a tight knot under the skin.

transmission

...

perception

occurs when pain is recognized, defined, and responded to by the individual experienceing the pain. In the brain, nociceptive input is perceived as pain.

addiction

overwhelming involvement with obtaining and using a drug for its psychic effects, not for approved medical or social reasons. (Psychological dependence)

Intrathecal

...

Name the typical medications used for epidural dosage.

epidural dosage (preservative free)
a) Morphine (Duramorph)-- 5mg/250ml (0.02 mg/ml)
b) Fentanyl (Sublimaze)--1250 mcg/250ml
c) Marcaine (a local anesthetic agent)

Most common adverse reactions to epidural analgesic

Respiratory depression, urinary retention, pruritis (atarax), nausea and vomiting

Special nursing requirement for epidurals.

Injected intermittently or infused continuously often requires a special "Nursing competency" and 2 RN signature

Advantage for using PCA.

Advantage:
• Decreases patient's need for opioids
• Can walk sooner
• Are able to be discharged home sooner
• Easily removed by the nurse or patient.

What should be moniotred when using PCA?

local anesthetic toxicity: peri-oral numbness, blurred vision, ringing in the ears (tinnitis), metallic taste in mouth, N & V, confusion, seizures.

pseudoaddiction

The development of drug-seeking behaviors among pain patients due to inadequate pain management.

Drug tolerance

After repeated administration of a narcotic, a given dose begins to lose its effectiveness; duration of action decreases & then the effectiveness of the analgesia.

Pain threshold

the least intense stimulus that will cause pain.

Physical dependence

After repeated administration of a narcotic, withdrawal symptoms occur when the drug is not taken. Affects are physiologic.

Pain theory by McCaffery

"Pain is whatever the experiencing person says it is and exists whenever he says it does". (McCaffery, 2002).

Pain theory based on Descartes

Pain is the stimulus. Response is the attempt to withdraw from the painful response. This theory ignores the emotional, psychological and cultural aspects of pain.

Gate control theory

(1965): A pain stimulus of a certain intensity opens a neurological gate, allowing the pain stimulus to proceed through the nervous system to the brain to create the sensation of pain. Also considers the emotional component of pain.

Name the four steps in pain transmission

Steps in pain transmission include:
1). A pain stimulus from the body is carried by A delta and C nerve fibers to the dorsal horn of the spinal cord.
2) The gate is located in the substantia gelatinose in the dorsal horn of the spinal cord. It can facilitate or inhibit the transmission of the nerve impulse through the CNS.
3) If the painful stimulus if of sufficient intensity or persists, the pain sensation is transmitted to the brain via the limbic system.
4) In the brain, the stimulus is recognized as pain and a pain response is elicited.

substantia gelatinose

...

nocioceptive pain name two types

somatic or visceral
Somatic - from skin, muscle, bone, joint, connective tissue.
Visceral pain -Internal organs and lining of body cavities.

Name two types of somatic pain

1) Superficial - from skin & SQ tissue- often described as sharp, burning, prickly
2) Deep- from receptors originating in bone, joints, muscles, tendons, etc. usually aching or throbbing.

neuropathic pain

damage to periphery or CNS; described as numbing, burning, shooting, stabbing.

What type of pain does visceral pain produce?

Referred pain -- pain perceived in an area other than from where stimulus originates; Due to complex multi-directional pathways of these fibers, pain from viscera may be perceived in a joint or skin, & vice versa.

Subjective assessment of pain the 5th vital sign.

document Patient's own words.
PQRST: quality, radiation, severity, time (duration)
b. Location: Try to isolate area; radiate?
c. Severity
1) Use scale of 0 - 10
2) Other scales available (Faces, colored analog, FLACC, etc.)
a) Faces may work with non-English speaking clients.

Assessing pain for comatose or cognitively impaired clients.

clients who cannot give a pain rating:
1) Assess & chart the client's behavior (e.g., moaning, restlessness, frowning, etc.)
2) Note & document any behavior change after pain med, Onset, alleviating or relieving factors, associated symptoms

Objective data for pain assessment (physical symptoms).

Manner of expressing pain
-Possible accompanying physical symptoms
a) Elevated BP, HR, RR --
b) Nausea
c) Perspiration
d) Pallor
e) Dilated pupils, etc.

Objective data for pain assessment (emotional symptoms)

Emotional symptoms
a) Anxiety
b) Anger
c) Crying
d) Withdrawal
e) Irritability

Objective data for pain assessment (effects on activity and rest)

3) Effects on Activity and Rest
a) Sleeplessness
b) Inability to perform ADL's, ambulate, etc.

Objective data for pain assessment (cognitive effects)

Cognitive effects
a) Decreased concentration
b) Inability to learn

Objective data for pain assessment (nutritional effects)

decreased appetite

somatogenic vs. psychogenic pain

Somatogenic vs. psychogenic pain
a. Pure physical pain is rare.
b. Pure psychogenic pain is rare.
c. Most pain sensation is created by a combination of somatic and emotional / mental stimuli.

malingerer

"One who pretends to be ill or suffering from a non-existent disorder to arouse sympathy."
-We must say, "I don't know why the patient hurts." & then we assess, report & treat the pain
-Lack of pain EXPRESSION does NOT mean lack of pain

somatogenic pain

originating in the body, pain with a physical cause we can find

psychogenic pain

Pain where a physical cause cannot be identified

Characteristics of non-opioids

Non-opioids
a. Anti-inflammatory, antipyretic and analgesic effects
b. Have an analgesic ceiling
c. Mild to moderate pain
d. All can be used in combination with an opioid in mod-severe pain.

Name three classes of non-opioids

1) Salicylates (Aspirin)
2) Acetaminophen - antipyretic or analgesic; negligible anti-inflammatory effect.
OFIRMEV= IV Tylenol: infused over 15min. 4g/d max.
3) NSAIDs: anti inflammatories, inhibit prostaglandin synthesis.

NSAIDs have been linked to a higher risk for

CV events MI, CVA, CHF

Do not take the following NSAIDs if recent surgery

a) Ibuprofen -- (Motrin, Advil)
b) Naproxen - (Naprosyn, Anaprox, Aleve)
c) Celecoxib (Celebrex)
d) Ketorolac ( Toradol)- short term treatment of moderately severe pain (<5 days)
e) Indomethacin (Indocin)- moderate -severe OA, RA, gouty arthritis

Naproxen

Aleve ( N.S.A.I.D.)

Celecoxib

-Selectively inhibits the enzyme COX-2 and inhibits prostaglandin synthesis to reduce inflammation, this relieves pain/inflammation in joins and smooth muscles (Celebrex, NSAIDs)

Ketorolac

short term treatment of moderately severe pain (<5 days), -only for "acutely moderate severe pain (Toradol)

Indomethacin

Indomethacin (Indocin)- moderate -severe OA, RA, gouty arthritis, Most preferred NSAID for RA

Agonist opioids

Bind to mu receptor sites & block the neuromediators that stimulate the nociceptors.
-1- Morphine --
Give PO, IM, SQ, IV, rectally, intrathecally (into epidural space).
MS Contin-- LA
-2- Hydromorphone - Dilaudid

-3- Oxycodone (Oxycontin) (LA)

-4- Fentanyl - IV, & as a duragesic patch

-5- Codeine

Mixed agonist and antagonist opioids

a) bind as agonists on kappa receptors and as weak antagonists or partial agonists on mu receptors
b) Less respiratory depression, but more agitation and dysphoria

Name 3 examples of mixed opiods

Examples:
-1 Stadol
-2 Nubain
-3 Talwin

dysphoria

abnormal depression and discontent

Talwin

...

Nubain

...

Stadol

Agonist-antagonist opiate analgesic

Side effects of opioids

a. Respiratory depression
b. Sedation- drowsiness, confusion
c. Pruritus
d. N & V, constipation, occasional allergic reactions
e. decreased BP &/or bradycardia

...

Combination Analgesics (Opioids and Non-opioids)
a. Oxycodone/Tylenol - (Tylox)
b. Oxycodone/aspirin - (Percodan)
c. Oxycodone/acetaminophen (Percocet)
d. Hydrocodone /acetaminophen (Norco, Lortab, Vicodin)- Vicodin comes in many dosage combinations- CAUTION: watch dose ordered and the medication available
e. Codeine in combination with aspirin or acetaminophen
f. Codeine dose in #2, #3, #4
1) #2 =15 mg Codeine
2) #3 = 30 mg Codeine
3) #4 = 60 mg Codeine

Adjuvant Medications (Coanalgesics):

drugs that add to the action or effect of opioids. Often used for chronic &/or neurogenic pain. Treat symptoms that aggravate pain (depression, seizures, inflammation) & tx. neuropathic pain.

Equianalgesia

Refers to the relative potency of various opioid analgesics compared to a standard dose of parenteral morphine
Equianalgesia= Narcotic conversion chart ie: morphine 1mg=dilaludid 0.2mg

Principle of Pain Relief Dosage:

Start with the lowest amount that relieves pain & increase gradually as needed.
Example: WHO -- 3-Step Analgesic Ladder for Treatment of Cancer Pain

3-Step Analgesic Ladder for Treatment of Cancer Pain

WHO -

Question of addiction of opioid study showed

In a prospective study of 12,000 hospitalized medical patients who received at least one narcotic, only 4 became addicted (<1%)

In another study by Friedman (1990) of > 24,000 patients receiving opioids for pain, only 7 patients became addicted! (0.0003%)

Adjuvant vs. "Potentiators"

Potentiators: make the opioid drug stronger or last longer.

Name 3 types of possible "potentiators" of analgesia

-1- Dextroamphetamine IM or PO -- rarely used.
-2- Ritalin PO --may be helpful in advanced cancer pain.
-3- Caffeine--100-200mg, combined with acetaminophen or ASA

Six Examples drugs that are "potentiators" of analgesia

1) Steroids -- Dexamethasone (Decadron), Prednisone -- bone, nerve pain.
2) Tricyclic antidepressants -- Amitriptyline (Elavil), Endep) -- used for nerve pain.
3) Anticonvulsants - (Tegretol, Neurontin)
4) Membrane-stabilizing drugs - (Flecainide, Catapres - Nerve pain.
5) Skeletal muscle relaxants—Flexeril
6) Antiemetics: ondansetron (Zofran)

Where are noericeptors located?

located within skin, connective tissue, muscle, and thoracic, abdominal and pelvic viscera;

How is a noericeptors process protective ?

it is warning signal that injury is about to or has taken place;
learn to move our hand away from burning flame, skinned knee, kidney stones, menstrual cramps, muscle strain, venipuncture, arthritis;
typically predictable and time limited based on extent of injury

What chemicals are released in noericeptor process 1st and 2nd set of neurotransmitters?

damaged tissue then releases variety of chemicals: substance P, histamine, prostaglandins, serotonin, bradykinin; chems are neurotransmitters that propagate pain message (action potential) along sensory afferent nerve fibers to terminate in dorsal horn of cord;

second set of neurotransmitters carry pain impulse across synaptic cleft to dorsal horn neurons: substance P, glutamate, ATP

...

can change into neuropathic pattern over time when pain has been poorly controlled; the constant irritation and inflammation caused by pain stimulus, the form of nerve cells alters, making them more sensitive to any stimulus and decreases number of opiod receptors

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set