N325 Quiz 2: Pain

gender differences in pain

men: less likely to report pain and to use alternative pain treatments than women

women: more likely to have pain (migraines, back pain, arthritis, fibromyalgia, neuropathic pain, abdominal pain, footaches), more likely to be diagnosed with a nonspecific somatic disorder, and less likely to receive analgesics for chest and abdominal pain

aging considerations

older adults are more likely to experience pain from a chronic condition, may expect pain as a part of aging and fail to report it, and may have cognitive problems that limit ability to describe pain; often manifested by depression and increased social withdrawal

cardiovascular responses to acute pain

increased BP and HR, resulting in enhanced alertness to threats

neurological responses to acute pain

increased pupil diameter, resulting in visual perception of threat

skin responses to acute pain

increased perspiration, resulting in removal of excess body heat

musculoskeletal responses to acute pain

increased muscle tension and activity, resulting in readiness for rapid motor activity

psychosocial responses to acute pain

increased apprehension, irritability, and anxiety, resulting in enhanced mental alertness

acute pain

pain that is usually short-term (< 3 months), caused by a specific injury or condition, and decreases over time

chronic pain

pain that persists for longer than three months that can be caused by a variety of factors and typically is persistent (ebbs and flows)

nociceptive pain

pain resulting from the normal processing of harmful stimuli that leads to tissue damage

superficial somatic pain

type of nociceptive pain arising from skin, mucous membranes, or subcutaneous tissue that is localized

deep somatic pain

type of nociceptive pain arising from muscles, fasciae, bones, or tendons that may be localized or diffuse/radiating

visceral pain

type of nociceptive pain arising from visceral organs such as the gallbladder or pancreas that is usually referred to cutaneous sites

functional pain

type of nociceptive pain characterized by pain and disability without a clear etiology involving persistent and complex physical symptoms

neuropathic pain

pain caused by damage to the nervous system, often described as burning or tingling (ex: diabetes, alcoholism, shingles, amputation, chemotherapy, nerve compression)

referred pain

pain perceived at a location other than the site of the painful stimulus as a result of interconnected sensory nerves, different than radiating pain, may be blocked using Ketamine

ischemic pain

pain caused by tissue hypoxia

transduction

the process by which noxious stimuli cause cell damage and lead to the generation of action potentials

transmission

the continuation of an action potential from the site of injury to the spinal cord, then to the brainstem and thalamus, and ultimately to the somatosensory cortex of the brain

perception of pain

the conscious experience of pain once it reaches the brain

modulation of pain

neurons originating in the brainstem descend to the spinal cord and release substances that inhibit nociceptive impulses

somatic mapping

a technique used to identify pain sources based on the body's sensory nerves

endogenous opioids

natural pain-relieving chemicals released by the brain to inhibit nociceptive impulses

core principles of pain management

• Everyone has a right to assessment/treatment of pain

• Pain is always subjective 

• Physiological/behavioral signs of pain are not reliable

• Pain is unpleasant

• Assessments must be appropriate for each patient

• Pain can exist without physical etiology

• Pain perception is individual

• Chronic pain sufferers may be more sensitive to stimuli

• Unrelieved pain has physiologic consequences

pain assessment goals

describe patient’s pain experience to design pain management techniques and identify realistic goals for therapy and resources for self-management (0/10 pain isn’t always possible)

PQRST assessment tool

Palliative/provoking: what triggers the pain or makes it better?

Quality: what does the pain feel like (sharp, dull, throbbing, burning, etc.)?

Region/radiation: where is the pain located, and does it spread?

Severity: how intense is the pain on a scale of 1 to 10?

Temporal factors: when does the pain occur, and how long does it last?

gate control theory

non-painful sensations can override and reduce painful sensations, so we can interfere with the pain transmission process and modulate responses via distraction

complementary interventions

non-pharmaceutical interventions such as massage, exercise, TENS, acupuncture/acupressure, heat or cold therapy, cognitive therapies, and immobilization that reduce dose of analgesic needed, minimize side effects, and don’t usually require a prescription

pain management principles

• Holistic approach: pain affects affects all areas of life

• Base treatment on pt goals: what is realistic for this patient? what are their functional goals?

• Pharm and non-pharm options: drugs are mainstay, but complementary treatments can work wonders

• Multimodal plan: when one med isn’t enough, patient may need two or more classes of analgesics

• Awareness of bias: all patients deserve to have their pain treated

• Collaboration: anesthesia, pharmacy, nursing, PT, OT, palliative care specialists

• Evaluate effectiveness: trial and error may be needed; reassess and adjust

• Manage side effects: CNS depression, constipation, n/v, dry mouth, tinnitus, itching, rash, etc.

• Patient teaching: what can/can’t they do? how to manage side effects? when to call?

• Understand policy: what are the laws in Texas? institutional policies? what are your responsibilities?

tolerance

a normal need for an increased opioid dose to maintain the same degree of analgesia

dependence

a normal physiologic response to ongoing exposure to opioids, manifested by withdrawal

pseudoaddiction

behaviors similar to those of addiction, because of inadequate treatment of pain

addiction

compulsive use, loss of control of use, and continued use of medication despite risk of harm

Naloxone (Narcan)

opioid antagonist used for suspected OD that precipitates complete withdrawal of opioids (endogenous and exogenous) and will cause S/Sx of withdrawal: n/v, diaphoresis, tachycardia, hypertension, yawning, tremors, abdominal cramping, etc.

epidural/intrathecal medication route

potent due to delivery close to receptors in dorsal horn so delivered in smaller doses (1mg = 300 mg po), complications include catheter displacement/migration and infection

implantable devices

pain pumps (meds) and spinal cord stimulators (electrical) may be used for pain management

patient controlled analgesia (PCA)

smaller but more frequent doses of medication dispensed by patient that use fluid as a driver to push meds through IV catheter, treated like narcotics (locked unit and two nurses to verify), patients must be appropriate candidate (able to hit button, appropriate cognitive awareness to recognize pain, understand time and dose constraints)

acetaminophen class/indication

analgesia, antipyretic

acetaminophen side effects/cautions

processed through liver so risk of hepatotoxicity in high doses, in many OTC products so check labels (look for acetaminophen, Tylenol, APAP)

acetaminophen dosage

325-650mg PO/PR q 4-6 hrs, not to exceed 4000 mg daily (3000 mg in chronic users, 2400 mg in elderly patients or those with liver, renal, or cardiac impairment)

NSAIDS medications

Ibuprofen, Naproxen, Aspirin, Ketoralac

NSAIDS class/indication

analgesic (anti-inflammatory)

NSAIDS mechanism of action

inhibits prostaglandin synthesis, metabolized through kidneys (ok to take with Tylenol)

NSAIDS side effects/cautions

GI upset, increased risk of GI bleed/perforation so look for dark, tarry stools (indicates upper GI bleed) and take with food, risk of kidney dysfunction

NSAIDS dosage

200 – 800 mg/ 4-6 hrs

opioids mechanism of action

bind with receptors in CNS and inhibit nociceptive input from periphery to spine (inhibit ascending pain pathways), alter limbic activity, opiate agonists

opioids side effects/cautions

respiratory depression, constipation, poor concentration, N/V, urinary retention, sedation (use POSS scale) itching, increased pain (OIH), not a good option for chronic pain because dose has to be continually increased to work due to tolerance

S on POSS scale

sleep, easy to arouse- acceptable, no action necessary, may increase opioid dosage if necessary

1 on POSS scale

awake and alert- acceptable, no action necessary, may increase opioid dosage if necessary

2 on POSS scale

slightly drowsy, easily aroused- acceptable, no action necessary, may increase opioid dosage if necessary

3 on POSS scale

frequently drowsy, arousable, drifts off to sleep during conversation- unnaceptable, monitor respiratory and sedation status until POSS score improves, decrease opioid dose 25-50% and notify provider, may administer non-opioid analgesic if not contraindicated

4 on POSS scale

somnolent, minimal or no response to verbal and physical stimulation- unacceptable, stop opioid, consider administering narcan, monitor respiratory and sedation status until POSS score improves

opioid indications

acute pain, chronic severe pain

Morphine (MS Contin) cautions

causes vasodilation- do not give to hypotensive patient, CNS depression, elderly, allergies, kidney dysfunction

Morphine (MS Contin) dosage

depends on route, typically 10-20 mg IV q4h PRN

Hydromorphone (Dilaudid) cautions

2-8x more potent than morphine, opioid naïve, elderly, low BMI, cognitive impaired

Hydromorphone (Dilaudid) dosage

0.5 mg – 2 mg IV (1.5 mg hydromorphine = 10 mg morphine)

Hydrocodone and oxycodone cautions

same as other opioids but typically PO rather than IV and may be mixed with acetaminophen

Hydrocodone and oxycodone dosage

5mg (naïve) to 20mg tolerate every 4-6 hours

Duloxetine (Cymbalta) class/indication

antidepressant (SNRI) for depression, peripheral neuropathic pain, generalized anxiety disorder, fibromyalgia, chronic musculoskeletal pain

Duloxetine (Cymbalta) mechanism of action

inhibits reuptake of serotonin and norepinephrine

Duloxetine (Cymbalta) side effects/cautions

nausea, dry mouth, headache, fatigue, sleepiness, can increase suicidal thoughts, risk of hepatotoxicity, risk for skin reactions, risk for orthostatic hypotension, risk of cognitive/motor function impairment

Duloxetine (Cymbalta) dosage

40-60mg PO daily

Gabapentin (Neurontin) class/indication

GABA analog for seizures, neuropathy, restless leg, insomnia, tremors

Gabapentin (Neurontin) mechanism of action

structurally related to neurotransmitter GABA, methods for analgesia unknown

Gabapentin (Neurontin) side effects/cautions

drowsiness, clients with CNS depression

Gabapentin (Neurontin) dosage

100 – 800 mg/day

adjuvant analgesic therapy

add analgesic effects, especially with neuropathic pain, includes corticosteroids (anti-inflammatory), antidepressants (modulate neurotransmitters), anti-seizure drugs (calm nerve cells), GABA receptor agonists (inhibit GABA), alpha-adrenergic agonist (alter pain perception), local anesthetics (inhibit nerve impulses), cannabinoids (modulate pain)