1. Medications for Pain Management
Chapter 17
Medications for Pain Management

2. Chapter 17
Lesson 17.1

3. Learning Objectives
Explain why there are so many rules about how narcotics and related analgesic drugs may be given
Compare and contrast drug tolerance and drug addiction
Evaluate different forms of narcotic agonists and narcotic agonist-antagonists in their ability to control pain

4. Learning Objectives (cont.)
List medications commonly used for the treatment of moderate to severe pain
List behaviors that would make you believe a patient is addicted to a drug.

5. Opioids Two Forms Classification of Action Natural: from opium
Synthetic: man-made
Classification of Action
Agonist
Partial agonist
Agonist-antagonist
Narcotics, or opioids, are substances that produce stupor and are used to treat severe pain.
Natural opioids come from opium, which in unripe seed capsules of the poppy plant. Opium contains chemicals such as morphine and codeine. Heroin chemically breaks down into morphine also.
Synthetic, or man-made drugs, were developed in an attempt to make drugs less addictive. Unfortunately, these drugs are just as potent but still are used because they do not have all of the effects of opioids.
Opioids would not be used for mild to moderate pain or chronic pain. Nonnarcotics such as ibuprofen (Motrin) or acetaminophen (Tylenol) would be indicated instead.

6. Opioids (cont.) Agonist Partial agonist Agonist-antagonist
Binds with the receptor(s) to activate and produce the maximum response of the individual receptor
Partial agonist
Produces a partial response
Agonist-antagonist
Acts as an agonist at one type of receptor and as a competitive antagonist at another type of receptor
The classifications and mechanisms of action are shown. The mechanisms of action for opioids is determined by where the drug binds to specific opioid receptor sites inside and outside the central nervous system.
The primary opioid receptors in the CNS are mu, kappa, delta, and sigma receptors.
Most analgesia is associated with the mu, kappa, and delta receptors. Most opioid action takes place at the mu and kappa receptors. Stimulation of the sigma receptors produces the most unwanted side effects.

7. Opioids (cont.) Morphine Codeine, hydrocodone, oxycodone Hydromorphone
Uses
Acute care
Hospice
Codeine, hydrocodone, oxycodone
Office or clinical setting
Hydromorphone
Severe pain unrelieved by morphine
Morphine is the main opioid drug to which all other pain management drugs are compared. Table 17-2 shows equivalent doses of opioid analgesics as compared to morphine.
Codeine, hydrocodone, and oxycodone are often used in combination with acetaminophen (Tylenol) for pain relief.
Hydromorphone is the most potent opioid listed and is used only if severe pain is unrelieved with morphine.
What are the side effects of opioids?

8. Pain “An unpleasant sensation or emotion that
produces or might produce tissue damage.”
- International Association for the Study of Pain (IASP)
Two Types
Acute
Chronic
Pain is subjective in nature. No one can truly experience another’s pain. People also vary in their pain perceptions.
“Pain is whatever the patient says it is.”—Margo McCaffrey, RN, Nurse Researcher
Acute pain is usually related to an injury, such as trauma, recent surgery, or infection, and disappears within an expected length of time.
Chronic pain is any pain that continues beyond the usual course of the acute injury process. Many people, such as those with chronic diseases such as rheumatoid arthritis or cancer, live with chronic pain.
Pain is the main reason people seek medical care.
Is psychologic pain real?

9. Pain Measurement Scales

10. Wong-Baker Faces Pain Rating Scale

11. Pain (cont.) Factors That Produce Pain:
An unpleasant stimulus that affects nerve endings and sets off electrical activity
Electrical signals that pass the stimulus along nerve endings to the spine
Signals that are carried to the brain
Development of behavioral, psychologic, and emotional responses in the brain
Researchers believe there are four things needed for pain to occur.
Different types of nerve fibers carry different pain signals.
Different types of measuring scales are used to put an objective rating on a subjective event. This helps the healthcare provider assess how the patient is perceiving the current symptoms in relationship to past pain occurrences.

12. Pain (cont.) Tolerance Dependence Addiction
The same amount of a drug produces a decreased effect over time
Dependence
A state in which the body will show withdrawal symptoms if the drug is stopped or reduced
Addiction
The uncontrollable need to have and use a drug for nonmedical reasons
All opioids cause tolerance and dependence. These are not the same as abuse.
Withdrawal symptoms are changes in the body or mind, such as nausea or anxiety, that occur when a drug is stopped or reduced after regular use. Tapering, or gradually lowering a drug’s dosage, can lessen the symptoms of withdrawal.
How do people describe the sensations experienced when they severely decrease their caffeine intake or cigarette use? Would these be examples of tolerance, dependence, or addiction?

13. Narcotic Agonist Analgesics
Action
Prevent pain perception in the central nervous system
Produce analgesia, sleepiness, euphoria, unclear thinking, slow breathing, produce miosis, decreased peristalsis, reduced cough reflex, and hypotension
Uses
Treat moderate to severe pain
The nerves that act have opioid receptors in the CNS (substantia gelatinosa [gray matter] of the spinal cord, brainstem, reticular formation, thalamus, and limbic system) and interact with the nerves of the autonomic nervous system that carry pain messages, which produce changes in the person’s reaction to pain. Narcotic agonist analgesics interfere with this CNS response.
Miosis refers to the pupil of the eye constricting or getting smaller.
What are some situations in which these medications would be used?
Has anyone ever taken one of these drugs? How did you feel?

14. Narcotic Agonist Analgesics (cont.)
Adverse Reactions
Bradycardia, slowed breathing
Hypotension, fainting
Anorexia, constipation
Confusion, euphoria
Dry mouth, vomiting
Pruritus, skin rash
There are many side effects of narcotic agonists. The most common side effects are listed above. Geriatric patients are more susceptible to these reactions and overdose.
In an overdose situation, respirations may fall below 12 per minute. Which drug is administered to counteract the effect of narcotic agonists?
Other symptoms of overmedication include sedation, coma, miosis, oliguria, clammy skin, and hypothermia.
Chronic overdose symptoms (seen in drug abusers) include very small pupils, constipation, mood changes, reduced level of alertness, skin infections, pruritus, needle scars, and abscesses.
Respiratory rate and sleepiness are the most closely watched symptoms of overdose.

15. Patient-Controlled Analgesia
Used when a continuous infusion of opioids is required
Pump is calibrated to ordered dose and frequency
Patient is able to self-administer pain med by pushing control button
Pump can be programmed to deliver an hourly rate
PCAs, or patient-controlled analgesia pumps, are used to deliver opioids at a constant rate (basal rate) per hour, or when the patient decides he or she requires the medication.
A “lock out” mechanism on the pump allows the patient to self-administer a dose within a specified time period. The pump “counts” patient “attempts” and “injections” received. The nurse is able to read the pump history to determine whether the pain medication is adequate.
The patient has to be able to understand how to push the controls to self-administer an injection. PCAs are not desirable for patients who are confused or very young.

16. Patient-Controlled Analgesia

17. Patient-Controlled Analgesia

18. Narcotic Agonist Analgesics (cont.)
Drug Interactions
Many drugs increase or decrease effects
Nursing Implications
Patient Teaching
Drugs that increase the effects of narcotics include other narcotic agonist analgesics, alcohol, antianxiety agents, barbiturates, anesthetics, nonbarbiturate sedative-hypnotics, phenothiazines, skeletal muscle relaxants, and tricyclic antidepressants.

19. Narcotic Agonist-Antagonist Analgesics
Action
Act on chemicals at specific nerve sites in the CNS, possibly in the limbic system
Produce analgesia, euphoria, and respiratory and physical depression
Uses
Relief of moderate to severe pain
Presurgical anesthesia
Active labor
Pain assessment and monitoring is crucial. Some organizations have called for pain assessment to be the “fifth” vital sign, but this is not universal.
There are many classifications of pain and scales to use. Three different rating scales are shown in Figure 17-1 of your text.

20. Narcotic Agonist-Antagonist Analgesics (cont.)
Adverse Reactions
Bradycardia or tachycardia
Hypertension or hypotension
Changes in mood, confusion, nervousness
Blurred vision, dizziness, headache
Weakness, nystagmus, syncope, tingling
Tinnitus, tremor, unusual dreams
Nausea, vomiting, dry mouth, constipation
The Agency for Health Care Policy and Research (AHCPR) clinical practice guidelines include the following mnemonic to help remember the principles of pain assessment: A-A-B-C-D-E-E. Refer to your text to help you review what each letter represents.

21. Narcotic Agonist-Antagonist Analgesics (cont.)
Drug Interactions
Caution with alcohol and CNS depressants
Nursing Implications
Patient Teaching
What teaching points will you reinforce with a patient taking narcotic agonist-antagonists?

22. Nonnarcotic Centrally Acting Analgesics
Action
Act at the level of the brain to control mild or moderate pain
Uses
Mild to moderate pain
Used in combination products for pain alone or when pain and fever are present

23. Nonnarcotic Centrally Acting Analgesics (cont.)
Adverse Reactions
Postural hypotension, dizziness
Disorientation, euphoria, headache
Light-headedness, minor visual disturbances
Sleepiness, slurring of speech, weakness
Skin rashes, stomach or abdominal pain
Dry mouth, nausea, vomiting, chills
Difficulty urinating, stuffy nose
Listed are the more common adverse reactions to nonnarcotic centrally-acting analgesics.
Overdose of the medications produces extreme sleepiness and slowed breathing. Elderly and weakened patients may react more strongly.
Cyanosis and low oxygen levels are present because of the slow breathing rate, hypotension, and weak heart function.
Hepatotoxicity also may occur in alcoholics who use the drug acetaminophen (Tylenol).

24. Nonnarcotic Centrally Acting Analgesics (cont.)
Drug Interactions
Nursing Implications
Patient Teaching
These medications have CNS depressant effects that add to those of other depressants (e.g., alcohol, sedative-hypnotics, tranquilizers).
These products tend to have fewer chemical interactions with other drugs than narcotics.
What are the nursing implications the LPN/LVN would need to consider before and after administration of these medications?
What are the key points that should be emphasized when teaching patients and families about these medications? Why should the additional use of OTC medications be a concern?