Download Agony of Pain

Agony
of Pain
Ethical and Rational
Approach to Pain
Management
August 2009
Disclosure of Conflicts
 I have no financial interests or significant
relationships that constitute a conflict of interest
related to this presentation in any of the following
categories:
 Equity holdings (mutual funds and pension funds
excluded)
 Board membership, consulting services or fees,
honoraria, speakers fees, gifts or other compensation
paid by any for-profit entity for speaking, attending
meetings or serving on an advisory board.
August 2009
Objectives
 Recognize the multiple manifestations of pain.
 Describe the differences between Tolerance, Physical
Dependence, Psychological Dependence, and Addiction; and
describe the approach towards patients with each of these
phenomena.
 Convert single parenteral doses of meperidine, morphine,
hydromorphone, and fentanyl to any of the alternates. (Dose
equivalence)
 List 4 reasons that physicians under-prescribe opioids.
 List 4 patient behaviors that alert the physician to opioid misuse
or addiction.
August 2009
Cancer Pain Impairs Quality of life
August 2009
What is Pain?
 Pain is an unpleasant sensation and
experience that in the acute state we
commonly associate with or describe in
terms of tissue damage.
 Chronic pain frequently resembles an
emotional state more than a sensation
August 2009
Clinical Picture of Chronic Pain
Constipation
Depression
Nausea/Vomiting
Pain
Control
Anxiety
Insomnia
August 2009
Current View of Pain Perception
August 2009
Long-term changes that can be measured
in patients suffering from persistent pain.
New pain fibers recruited and
stronger signals.
August 2009
Inadequate Pain Control
Russell Portnoy: “more than 40% of
cancer patients are under treated” for
their pain.
WHO Guidelines
 By following the WHO Guidelines cancer
pain can be controlled 70-90% of the time
August 2009
Reasons that physicians do not use adequate
pain medications (1)
 Failure to ask about or evaluate pain
 Disbelief of patient report of pain
 Fear that patient will become “addicted”
August 2009
Reasons that physicians do not use adequate
pain medications (2)
 Lack of knowledge about how to use
opioids safely and effectively
 Fear of respiratory depression
 (Sedation usually precedes)
 Fear of accelerating death
 Belief that some suffering is necessary
 Fear of regulatory sanctions
August 2009
Other factors that are associated with under
treatment of pain

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Minority or lower S-E status
Women
Elderly
Dementia
No family advocate (e.g. in nursing home)
History of substance abuse
Lack of availability
Cultural differences
August 2009
Elderly & Pain Control
 Nursing home study showed that in the last
3 months of life 70% of patients had severe
or moderate pain
 ¼ of elderly cancer patients received no
analgesic for daily pain
 Patients over 85 are 50% less likely to
receive any analgesia than patients 65-74
August 2009
Patient reluctance to take pain
medications
 Fear of the medications/misconceptions
 Fear of addiction, getting “hooked
 Wanting to save narcotics for when pain gets bad



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Denial of the pain/disease process
Stoicism
Desire to be liked by the physician
Concerns about distracting the physician from the
disease
 Non-compliance
August 2009
Pain in Cancer and
Sickle Cell Anemia
 Pain associated with malignancy or sickle
cell disease is a
 constant reminder
 the person’s condition (limited life span)
 imagined fate (worsening pain, shortness of
breath, painful death)
August 2009
Why Clock Watching? Inadequate
Scheduled Dose
August 2009
The E.R.A. of
Effective Pain Control
1. Evaluate the pain problem
2. Remove or reduce the physical source of
the pain
3. Alleviate the symptoms
August 2009
Evaluation and Treatment Planning for
Pain in Cancer (1)
 What is the background of patient and pain
problem?
 Nature of primary underlying disease
 Physical condition and performance status of
the patient, including co-morbid diseases
 Psychological, emotional, social situation of
patient
 Prior history of alcohol or drug use, misuse or
abuse
August 2009
Evaluation and Treatment Planning for
Pain in Cancer (2)
 Characteristics of the pain - requires thorough
assessment
 Quality, Severity
 Onset, duration, frequency
 Exacerbating and alleviating factors
 Impact on function (work, sleep, eating,
relationships)
 What is the availability and practicality of potential
methods of pain relief?
August 2009
Evaluation and Treatment Planning for
Pain in Cancer (3)
 Steps in pain management
 Set Goals
 Plan Initial Analgesic Therapy
 Discuss Re-evaluation and Adjustment
 How soon
 Consider Issues of tolerance, toxicity
 Make Adjustments for prior history of alcohol or drug
abuse, which may increase dose requirements
 Evaluation and treatment of other medical and
psychological problems
August 2009
Self Report
Method of Pain Measurement
 Procedures
 Verbal description of the pain
 Pain score (0-10)
 Visual analog scale
 Functional assessment of activity
 Value
 Recognizes subjective nature of pain perception
 Observer’s bias not interjected
 Simple quantification
 Limitations
 Influenced by psychological state and “drug-seeking”
behavior as well as nociceptive or neuropathic stimuli
August 2009
Signs of Pain
 Agitated or irritable behaviors
 Depressed mood
 Loss of interest and decreased overall
activity level
 Decreased Mobility
 Disturbed sleep
 Reduced appetite
These may differ in chronic and acute pain
August 2009
Clinical Mechanisms of Pain
Stimulation of peripheral pain receptors or
damage to afferent fibers
 Compression, stretching, invasion or chemical irritation of
receptor, nerve, root, or plexus




Inflammation, infection, necrosis, or other tissue damage
Obstruction of a viscous
Occlusion of a vessel with engorgement or ischemia
Infiltration and tumefaction of tissue invested by capsule,
fascia, or periosteum
 Inflammation of nerves and vessels
 Spontaneous activity in nerves damaged by disease or
treatment
August 2009
Removal or Reduction of the
Physical Source of the Pain
 Surgery - Bypass or removal of obstructing lesion; fracture
fixation; bypass arterial obstruction
 Radiation Therapy - Shrink regional obstructing, infiltrating,
stretching, or pressing tumor.
 Chemotherapy - Reduce tumor burden systemically (e.g.
lymphoma)
 Antibiotics, corticosteroids - Decrease inflammation and
cytokine production
 Cytokine inhibitors - Anti-tumor necrosis factor alpha
antibodies (infliximab) - mediation of immune function
August 2009
Alleviation of Symptoms
Reduce Peripheral
Reception
Steroids, NSAID’s,
antipyretics
Block Conduction of
Impulses
Local anesthetics, CNS
opioids,  2 adrenergic
agonists
Interfere with
perception and
affective responses
Opioids, ? Adjuvants
August 2009
(TCA’s, anti-convulsants,
SSRI’s, SNRI’s steroids)
Pain Types and
Selection of Analgesic Agents
Somatic
NSAID’s, anti-pyretics,
corticosteroids.
Visceral
Opioids
Neuropathic
Tricyclic anti-depressants,
SSRI’s,selective serotonin
and norepinephrine reuptake
inhibitors (SNRI’s)
Anti-convulsants
August 2009
Principles of Analgesic Administration
 Avoid parenteral route when
possible
 Administer majority of daily dose
on a scheduled, not PRN basis
 Give at a sufficient dose and short
enough interval to prevent pain
from becoming moderate or
severe (< 5/10 on pain scale)
 >5/10 affects quality of life.
August 2009
PRN vs. Scheduled Doses
Toxic level
Effective Control
Pain
Poor
Control
Toxic level
Effective Control
Pain
August 2009
Good
Control
Desirable Characteristics of Analgesics for
Patients with Chronic Pain
 Effective by the oral or trans-dermal route
 Moderate to long duration of action (4-12
hours)
 Minimum of adverse side effects at
effective doses
August 2009
Starting Doses of Strong Opioid
Analgesics
Drug
Morphine
Dilaudid
Oxycodone
Oral
5-15 mg q 3-4 hr
1-4 mg q 3-4 hr
5-10 mg q 3-4 hr
Parenteral
3-5 mg q 3-4 hr
0.5 - 1.5 mg q 3-4 hr
N/A
Fentanyl, transdermal: 25 micrograms/hr (Difficult to titrate)
August 2009
Converting Parenteral to
Long Acting Oral Narcotics
Determine 24 hour dose of IV morphine
E.g., Total 24 hour dose IV morphine = 80 mg
Calculate oral equivalent
80mg x 3 = 240 mg oral morphine
Start with 50% of calculated dose
120 mg MS-Contin (60 q 12 h) or
80 mg Oxy-Contin (40 q 12 h)
August 2009
Quick and Dirty Dose Equivalence
Single
IV Dose
Meperidine Morphine
(Dem erol) *
Hydro
morphone
(Dilaudid)
Fentanyl
(Duragesic)
100 mg
1 mg (1.5)
0.1 mg
10 mg
Hourly
IV Dose
25 mg
2.5 mg
0.25 mg
50 mcg
(Has
shorter
T1/2)
Q4h
Oral
dose
300 mg
30 mg
6-8 mg
NA
* Not good for chronic pain
August 2009
Methadone - Effective Long-Acting Oral
Opioid for Chronic Pain in Cancer
Morphine to Methadone Conversion
1400
Mg Oral Morphine
Use short acting
opioid for breakthrough pain
Estimated methadone per
day (mg) = (oral morphine
per day (mg)  15) + 15
1200
1000
800
600
400
200
0
0
10
20
30
40
50
60
Mg Oral Methadone
W Plonk, J Palliat Med 8:478,2005
August 2009
70
80
90
100
Opioid Side Effects
 Direct CNS or PNS - Sedation, euphoria,
delirium (hallucinations), respiratory depression
myoclonus (All dose related)
 GI - Nausea, vomiting, constipation
 GU - Urgency, difficulty voiding, SIADH
 Cutaneous - Itching
 Dependence - Physical, psychological
 Tolerance
August 2009
Tolerance
 The requirement for larger doses to obtain
the effects observed with the original dose
 A physiological phenomenon
Not a sign of weakness, moral turpitude,
psychological dependence, or addiction
August 2009
Physical Dependence
 An altered physiologic state produced by
the repeated administration of the drug
which necessitates the continued
administration of the drug to prevent an
abstinence or withdrawal syndrome.
August 2009
Psychological Dependence
 The effects produced by the drug or the
conditions associated with its use are
necessary to maintain an optimal state of
well being. (Perceived)
May lead to compulsive drug use or abuse.
August 2009
Addiction
 A behavioral pattern of compulsive drug
use characterized by overwhelming
involvement with the use of the drug, the
securing of its supply, and a high tendency
to relapse after withdrawal. Function of
patient is impaired.
 Occurs RARELY in patients with cancer
pain. (< 1/1000)
August 2009
Pseudoaddiction
 Phenomenon seen in a patient who seeks
additional medications appropriately or
inappropriately because of significant
undertreatment of their pain
 An iatrogenic syndrome that may mimic behaviors
usually associated with addiction, and which is
caused by the under medication of pain
August 2009
Characteristics of Drug Abuse Predictive of Addiction
in Patients Receiving Opioids for Pain
 Drug use impairs rather than improves patient function
(Reduced occupational, social, and recreational activities.),
medical condition,and quality of life
 Drugs obtained from more than one physician or pharmacy
after being asked to use only one
 Frequent “losses” of drug
 Frequent occasions where greater opioid use than was
intended
 Selling prescription drugs
 Forging prescriptions
 Stealing drugs
 Injecting oral agents
August 2009
Approaches to Pain Management of
Patient with Substance Abuse Problems
 Physician must set parameters for
opioid use more closely than for
other patients
 Open discussion with patient
about issues of concerns
 Avoid “blaming”, but don’t gloss over
magnitude of problem
 Let patient know that you can work
together, but there will be tight
control
August 2009
Alternative Methods to Control Abuse in Patient with
History of or Current Substance Abuse Problems
 Written Contract that explicitly
delineates the intention of the
physician to help, the obligations of
the patient who wishes the help,
and the consequences of failure to
fulfill the obligations.
 Less formal understanding reached
between the physician and patient
August 2009
Possible Consequences of Failure to
Meet Obligations
 Severing physician-patient relationship
 Discontinuation of ordering any opioids
 Notification of legal authorities,
pharmacies, other medical facilities
 Closer control of opioid availability by
decreasing interval for new prescription.
August 2009
Dependence Issues
 Habituation abuse rarely a clinical problem
 7/24,000 among patients with no history of addiction
 Tolerance can be overcome by increasing the
dose
 Physical dependence effectively managed by
tapering dose as the pain abates
 Psychological dependence and pseudo-addiction
minimized by giving sufficient doses at regular
intervals
August 2009
Special Populations
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Substance abuse history
Active addict
Person who injures self to get medication
Geriatric
Cognitively impaired (Difficult to assess)
Dying
August 2009
Additional Cancer Pain Control Methods
Useful in Selected Situations
•
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•
•
•
•
•
Transdermal narcotics (Fentanyl)
Sub-lingual morphine, fentanyl “lollipops”
Transcutaneous electrical nerve stimulation
Epidural or sub-arachnoid opioids
Continuous infusion narcotic
Patient controlled analgesia (PCA) pumps
Biofeedback
Nerve, ganglion, plexus block
August 2009
Rational Approach to Cancer Pain
Management - Summary
 Pain impairs quality of life
 Most cancer pain can be controlled through
careful assessment, planning, and
informed therapy
 Physical and psychological side effects are
real issues, but can be minimized
 The knowledgeable and compassionate
physician and nurse are key to effective
care.
August 2009
Thank You