Chronic Pain & Drug Therapy – Pharmacology
This quiz is about chronic pain and drug therapy of pharmacology.
Visceral Pain
Arises from internal organs
Deep aching or sharp stabbing pain
Neuropathic Pain
Arises from injury to nerves
Burning, shooting, stabbing
Abnormal pain processing
Makes difficult to treat
Types of Pain
Acute
Chronic
Caner Chronic Pain
Chronic Non-Cancer Pain
Acute Pain
Short duration (< 3-6 months)
Identifiable cause
Acute pain ↓ as healing occurs
Severity of pain equals acuity of the injury or disease process
Specific & localized in nature
Drugs usually work
Sympathetic nervous system response
Fight or Flight Response
hypertension, tachycardia, restlessness, anxiety, diaphoresis/pallor, urinary retention, anxiety/agitation/confusion
Chronic Pain
Caner Chronic Pain
Chronic Non-Cancer Pain
Pain lasts > than 3-6 months.
Sometimes identifiable cause
Pain severity > stage of the injury or disease
Often periods of waxing and waning
Requires more and more drug therapy
Persists beyond healing stage
NO sympathetic nervous system responses.
Depression, irritability, flat affect, fatigue, decrease physical activity, withdrawal
Characteristics of Pain
Acute
Mild to severe
Sympathetic NS response
Related to tissue injury
Restless and anxious
Reports pain
Behavior indicative of pain
Chronic
Mild to severe
Parasympathetic NS response
Continues beyond healing
Depressed and withdrawn
Does not mention pain
unless asked
Pain behavior often absent
Pain Relief
Endorphins
Morphine-like substance
Able to “close the gate”
Gate Control Theory
Theory about how pain is transmitted and blocked
Proposes that only one pain pathway (gate) is open at one time. The brain therefore does not perceive pain while it is preoccupied with other sensory input.
Explains how massage, vibration, heat, and cold reduce pain sensations
Melzack & Wall, (1965)
When should you assess for pain?
on admission
pain is the 5th vital
at all encounter with pt
be alert for pain
identify pt at risk
for pain
Don’t wait to be told
Pain Assessment
PQRST
PQRST
Provoking factors
Quality
Region or radiation
Severity or intensity
Time
Pain Assessment
COLDERR
Character
Onset
Location
Duration
Exacerbation
Relief
Radiation
Pain Assessment
OLDCART
Onset
Location
Duration
Characteristics
Agravating
Relieving
Treatment
Why Use a Pain Scale ???
Quantify data with a number
Maintain consistency between ratings
Make the data objective
Note: Some facilities may make it policy to use one or more particular scales
Non-Verbal Pain Assessment
Observe the patient for 3-5 minutes
Behavioral Pain indicators
Facial Expressions
Vocalizations
Behavior changes
American Geriatric Society Panel On Persistent Pain In Older Persons
Identified 6 common pain indicators
Facial expressions of grimacing, 1.crying
2.Verbalizations
3.Body movements
4.Changes in interpersonal interactions
5.Changes in activity or routines
6.Mental status changes
Psychosocial Aspects of Pain
Meaning of pain to patient and family
Past experiences with pain
Effect on:
all aspects of all life
daily activities
relationship
enjoyment
family and financial
Spiritual & Cultural
Addiction
Chronic
Many factors influence addiction
Occurs over time
Defined:
Impaired control over drug
Compulsive use
Continued use despite harm and craving
Pseudoaddiction
Addictive Behaviors” because pain is under treated
Anger/esculating demands for more meds
Results in suspicion and avoidance by staff
Common with chronic pain
Behavior resolved when pain is adequately treated
Tolerance vs. Physical Dependence
Tolerance
Tolerance
Repeated use decreases the effect of drug over time
patient need increasing doses to achieve same pain relief.
Physical dependence
Physical Dependence
Results in physical withdrawal symptoms when drug abruptly discontinued, rapid dose reduction or reversal agent given
Occurs in everyone who takes opioids over long period of time
Withdrawal
Important role of nurse is to assess for and prevent withdrawal
Symptoms of opioid withdrawal:
Nausea, vomiting
Abdominal cramping
Sweating
Delirium
Muscle twitching
Convulsions
Substance Abusers
Often result of traumatic injury or health problems that cause pain
Patients with chronic pain medication use should not have medications stopped abruptly
May require higher doses of conventional drugs
Should be identified so appropriate therapy can be prescribed
Placebo Therapy
Only indicated use is in research studies
Need informed consent
Is unethical to administer placebos to your patients
Before Administering Pain Medications
The nurse should:
Assess for drug allergy
Ask patient’s current medications
Assess the patient’s current pain status
Check vital signs
Drug Groups
Non-Opioids
Opioids
Adjuvants
Pain Treatment
Mild (1-3)
Non-opiods
Moderate (4-6)
Weak opioids
Severe Pain (7-10)
Strong opioids
Adjuvants: Can be used at every level of pain
Non-Opioid Analgesics
Most Common
Acetylsalicylic acid (aspirin)
Acetaminophen (Tylenol)
Most are NSAIDs, including aspirin:
Adverse effects: GI disturbances, bleeding
COX-2 inhibitors for long-term use
Opioid Analgesics
Used in management of all types of pain
Work centrally to block release of neurotransmitters in spinal cord
Bind to MU receptors to block release of substance P which prevents the transmission of pain
Most opiods are similar in effect
Response varies widely
Can be administered in many different routes
Opioids
Opioid Agonists: Bind and cause analgesia. By binding to pain receptors they block the transmission of pain to the brain.
Example: Morphine Sulfate
Opioid antagonists: bind to receptors but do not cause analgesia.
Example: Naloxone (Narcan). It is used for overdose, oversedation secondaryto opioids.
Opioids
There is no analgesic dosage ceiling (limit)
Side effects include:
Respiratory depression
Sedation
Constipation
Itching
Nausea & vomiting
Urinary retention
Postural Hypotension
Also have antitussive and antidiarrheal properties
Equalanalgesic Dosing
Not all opioids are the same strength
Morphine sulfate is the gold standard
standard against all other opioids are measured
Weak Opioids
Used for moderate pain and are often found in combination medications
Codeine and Tylenol (Tylenol#3)
Hydrocodone and Tylenol (Vicodin, Loratab)
Oxycodone and Tylenol (Percocet,Tylox).
Strong Opioids
Opioids for moderate to severe pain
Morphine Sulfate
Hydromorphone (Dilaudid)
8 times stronger than morphine
Fentanyl (Duragesic)
IV (acute pain, on pump)
Patches, oral (chronic and cancer pain)
Meperidine (Demerol)
Methadone (Dolophine)-chronic pain or drug dependent patients
Meperidine-Demerol
Synthetic opioid
Toxic metabolite, normeperidine that can cause seizures.
Meperidine half life 2-4 hours
Normeperidine half life 24-48 hours with normal renal function.
Should only be used for a short period of time (2-3 days)
Meperidine Toxicity
-Older adults at high risk
People with decreased renal clearance
Assess patients for complaints of numbness, twitching, confusion and seizures
Professional Role of Nurse:
Ensure Comfort and Safety
Assess for pain
Monitor BP & Respirations prior to administration
Believe the patient
Medicate with appropriate medication
Assess for adverse effects
Expected Outcomes: Pain relief and drowsiness
Sedation occurs before respiratory depression
Respiratory Assessment
Monitor rate and depth of respirations
Especially while sleeping
Severe respiratory depression usually seen with IV administration or in patient with no tolerance to opioids
Treatment for Respiratory Depression
Attempt to arouse patient
Administer opioid antagonist Naloxone (Narcan) IV
Fast acting
Reverses opiod effect
Pain will quickly return
Continue to monitor as effects of respiratory depression will outlast the Narcan and respiratory depression can reoccur
Nursing Interventions to Prevent Side Effects of Opiods
Ongoing assessment for over sedation and respiratory depression
Assess for constipation
Push fluids & encourage ambulation
Administer stool softeners & laxatives as ordered
Nausea & vomiting
Administer antiemetics as prescribed
Routes of Administration
oral
Oral
Preferred route for pain control
Especially chronic
Expect onset in 30 minutes
Long acting and controlled release available
May not be crushed
Routes of Administration
Intramuscular
Intramuscular
Variable absorption rates
Tissue fibrosis and abscess can form after repeated injections
Onset 30-45 minutes
Not recommended for pain control
Intravenous
Onset within minutes
Most efficient
Routes of Administration
Transdermal
Transdermal
Fentanyl (Duragesic)
Long duration of action (48-72 hours)
Rectal Suppository
Absorbed through the rectal mucosa
Many opioids can be administered via this route
Slower onset of action
Sublingual/ Buccal
Sublingual-placed under tongue
Buccal: Fentanyl (Actiq) oral transmucosal system
Intranasal
Butorphanol (Stadol) agonist-antagonist
Sumtatriptan for migraines
Good for out-patient use
PCA
PCA (Patient Controlled Analgesia)
Patient controls delivery of medication
Dosage preset
Advantages
Use less drug
Fewer side effects
Less time for nurse
Vital Signs, pain level,side effects monitored closely
Patient Controlled Analgesia
PCA
Settings: continuous, PCA or continuous with PCA
Example of an order:
Morphine Sulfate
Loading dose 2 mg
0.5mg continuous
PCA dose 1mg
Lockout 6 minutes
4 hour limit: 20mg
Benefits and Risks
Benefits
Empowers patients
Better control of pain
Reduces patient anxiety
Risks
Over sedation and respiratory depression
Drug administration set-up errors
Others besides patients pushing the button
Nursing Responsibilities
Monitor for adverse effects & follow protocols
VS & sedation levels every 2 hours
Assess for other side effects:
-Urinary retention
-Nausea
-Itching
-Consitpation
Educate patients on proper use and what to report
Obtain other pain therapies for patients who cannot administer PCA competently
Adjuvant drugs
Not true analgesics
Work alone or in combination to relieve pain
Enhance or potentate effectiveness of pain relief
Good with chronic pain and complex pain syndromes
Examples
Tricyclic antidepressants
Antiseizure medications
Antianxiety drugs
Corticosteroids
Topical and Local Anesthesia
Topical anesthesia
Local anesthetic infusion pumps: ON-Q Pump
Adjuvant Drugs
Benefits:
-Reduce need for opiods
-Work better for some types of pain
-Treat associated symptoms of depression and sleep disorders with chronic pain
Best Practices for Scheduling of Medication
-Pre-medicate for painful procedures/activities
-Around the clock dosing preferred
–Assess minimum every 4 hours
-Treat pain early for better effect
-Breakthrough dosing for cancer pain
-Follow BRN of CA guidelines
Nonpharmacological Interventions
Cognitive-Behavioral Measures
Alternative Medicine
Complementary Medicine
Cutaneous Stimulation
-Application of heat and cold
-Therapeutic touch
-Vibration
-Massage
Trancutaneous Electrical Stimulation
TENS
Cutaneous electrical stimulation
Usually initiated by PT
Empowers patient and gives some control
Physical Measures
Physical Therapy & Occupational Therapy
Goal to increase function, decrease pain
Methods:
–Splints
–Exercise
–Heat and cold therapies
Pain
#1 reason to seek medical attention
Cognitive-Behavioral Therapy
Distraction
Very effective
Transient, best used with other measures
Guided imagery
Hypnosis
Modify environment
Meditation
Vibration
Music
Alternative Therapies
Acupuncture
Accupressure
Magnet therapy
Aromatherapy
Pain Management In The Elderly Patient
Pain is prevalent in the elderly
At risk for under treatment
Don’t describe the pain as “pain” but may call it discomfort, or soreness
Tend to report less often
May view as sign of weakness or
something to be lived with
Don’t want to be a bother
Assessment Guidelines In The Elderly Patient
Assume pain is present
Ask about present pain only
Use a standard scale
Use a variety of descriptors
ache, sore, hurt
If cognitively impaired assess for non-verbal symptoms of pain
Management of Pain in the Elderly
Use round the clock dosing
Start low and go slow
Monitor for adverse effects
Drug interactions
Avoid use of meperidine (Demerol)
Use nondrug therapies
Definition of Pain
Unpleasant sensory and emotional experiences associated with actual and potential tissue damage
study of pain 1979
Definition of Pain
Whatever the experiencing person says it is, existing whenever s/he says it does.
Margo McCaffery (1968)
Nurse As An Advocate
Primary role of the nurse in pain management is believing their patients.
The Joint Commission Pain Standards
American Pain Society
Pain Care Bill of Rights
Patients have the right to be taken seriously and treated
Have pain assessed and promptly treated
Have ongoing reassessment & evaluation
Treatment modified if not working
Referral to pain specialist for persistent pain
Myth/Misinformation
Contribute to Ineffective Pain Management
Too much pain medication too frequently constitutes substance abuse, causes addiction, will result in respiratory depression or will hasten death
language barrier
comatos pt
baby
dementia
culture
High Risk Population for Under treatment
Infants and children
Older Adults
minorities
cognitive dysfunction
emotional /mental illness
addicts
pt with terminal ill
cultural difference
pt who speaks a difference langugue
Untreated Pain
Physiologic Impact
Quality-of-Life Impact
Financial Impact
ABCs of Pain Management
A-Ask, Assess
B-Believe
C-Choose appropriate medication
D-Deliver the medication in a timely, logical, coordinated fashion
E-Empower the patient
Nurses’ Attitudes/Barriers
Attitudes of health care providers and nurses affect interaction with patients experiencing pain.
Individual experiences with pain
Personal use of meds or Nonpharmacological methods to manage pain
Family’s or SO’s hx or experience with substances for pain control or mood altering effect
Physiology of Pain
Periphery ——>Noxious stimuli
Physiology of Pain
Nociception
Transduction
Transmission
Perception
Modulation
Transduction
Pain Stimulation
Tissue damage—> release of chemicals——> increase excitability and frequency of nerve impulses
Neurotransmitters
Release of multiple substances
Examples
Potassium
Serotonin
Bradykinin
Histamine
substance P
prostaglandins
Transmission
Pain Transmission
To be perceived the pain stimuli must be transmitted first to the spinal cord
Then signals sent to the central areas of the brain
Transmission
Slow or Express Train?
A Delta fiber small, myelinated fibers; send impulses quickly producing sharp, pricking, well localized pain of a short duration.
C Fiber smallest, unmyelinated fibers, send impulses slower producing dull, aching, burning sensations with a diffuse, slow onset of a long duration
Perception
Conscious experience of Pain
Involves several brain structures
Reticular activating system: autonomic response (sympathetic nervous system)
Somatosensory system: localization and characterization of the pain
Limbic: emotional and behavior responses
Cortical: meaning of pain
Pain Tolerance
Pain tolerance: The maximum degree of pain intensity that a person is willing to experience.
Ex: Bad day….stub toe….worst pain ever experienced
Factors Affecting Pain
Age
Gender
Women have more:
pain in women
Headaches
Arthritis, fibromyalgia
Men have more:
Gout
PVD
Back pain
Sociocultural background
Genetics
Physiologic Sources of Pain
Nociceptive —>normal
Neuropathic—>abnormal
Nocioceptic
Normal processing of pain
2 Types Somatic and Viceral
Somatic
Superficial: Skin and tissues (incisions, drains)
Sharp and burning
Deep somatic: Bone, muscle, blood vessels (muscle spasms, orthopedic procedures
Dull, aching, cramping