Management of Pain and Discomfort

The Elusive Nature of Pain

• The degree to which pain is felt depends on:
  • How it is interpreted.
  • Context in which it is experienced.
  • Cultural component: Some cultures react more intensely to pain than others.
  • Gender differences: Women show greater sensitivity to pain.

Significance of Pain

• Provides feedback about the functioning of our bodily systems.
• Symptoms can lead a person to seek treatment.
• Inadequate pain relief is a common reason for euthanasia or assisted suicide requests.

Measuring Pain

• Verbal reports:
  • Informal vocabulary used to describe pain.
• Pain questionnaires:
  • Assess the nature and intensity of pain.
  • Address psychosocial components (fear, impact on life).
• Methodological tools:
  • Used to gain insights about pain.
• Pain behaviors:
  • Arise from chronic pain.
  • Assess how pain has disrupted a patient’s life.
  • Define characteristics of different pain syndromes.

Physiology of Pain

• Protective mechanism: Brings tissue damage into conscious awareness.
• Accompanied by motivational and behavioral responses.
• Negative emotions can exacerbate pain and vice versa.

Kinds of Pain Perception

• Mechanical nociception:
  • Results from mechanical damage to tissues.
  • Nociception: Pain perception.
• Thermal damage:
  • Pain due to temperature exposure.
• Polymodal nociception:
  • Pain that triggers chemical reactions from tissue damage.

Gate-Control Theory of Pain

• Developed scientific understanding of pain.
• Nociceptors sense injury and release chemical messengers to the spinal cord.
• A-delta fibers:
  • Small, myelinated fibers.
  • Respond to mechanical or thermal pain.
  • Transmit sharp, brief pains rapidly.
• C-fibers:
  • Unmyelinated nerve fibers.
  • Involved in polymodal pain.
  • Transmit dull, aching pain.
• Periductal gray:
  • Located in the midbrain.
  • Results in pain relief when stimulated.
• Processes in the cerebral cortex are involved in cognitive judgments about pain.

Neurochemical Bases of Pain and Its Inhibition

• Endogenous opioid peptides:
  • Natural pain suppression system of the body.
• Stress-induced analgesia (SIA):
  • Phenomenon where acute stress reduces sensitivity to pain.

Acute and Chronic Pain

• Acute pain:
  • Results from a specific injury that produces tissue damage.
  • Disappears when the tissue is repaired.
  • Short in duration (six months or less).
• Chronic pain:
  • Begins with an acute episode but does not decrease with treatment and time.

Kinds of Chronic Pain

• Chronic benign pain:
  • Persists for six months or longer.
  • Relatively unresponsive to treatment.
  • Severity of pain varies.
• Recurrent acute pain:
  • Intermittent episodes of acute pain but chronic condition.
  • Recurs for more than six months.
• Chronic progressive pain:
  • Persists longer than six months, increases in severity over time.
  • Associated with malignancies or degenerative disorders.

Common Sources of Chronic Pain

• Back pain: 70-85% of Americans experience it.
• Headaches: Approximately 45 million Americans have chronic recurrent headaches.
• Cancer pain: The majority of advanced cancer patients suffer moderate to severe pain.
• Arthritis pain: Arthritis affects 40 million Americans.
• Neurogenic pain: Pain resulting from damage to peripheral nerves or the central nervous system.
• Psychogenic pain: Pain not due to an identifiable physical cause.

Acute versus Chronic Pain (Psychological Profiles)

• Chronic pain:
  • Has an overlay of psychological distress.
  • Patients develop maladaptive coping strategies.
  • Interaction of physiological, psychological, social, and behavioral components.
  • Pain control techniques are not effective.

Factors That Result in Chronic Pain

• Predisposition to react to bodily insult with a specific response.
• Exacerbated by stress or efforts to suppress pain.
• High sensitivity to noxious stimulation.
• Impairment in pain regulatory systems.
• Overlay of psychological distress.

Chronic Pain Patient

• Pain is exacerbated by:
  • Inappropriate prior treatments.
  • Misdiagnosis or inappropriate prescriptions.
• Lifestyle:
  • Quits jobs and abandons leisure activities.
  • Withdraws from families and friends.
  • Requires public assistance.
• Experiences loss of self-esteem.
• Receives compensation (incentive for being in pain).
• Relationships:
  • Family relationships get affected.
  • Positive attention from spouse may maintain the pain.
• Behaviors:
  • Alterations in lifestyle interfere with successful treatment.
  • Understanding pain behaviors.
  • Knowing whether they persist after treatment.

Pain and Personality

• Pain-prone personality:
  • Predisposes a person to experience chronic pain.
• Personality attributes associated with chronic pain:
  • Neuroticism.
  • Introversion.
  • Use of passive coping strategies.

Pain Profiles

• Minnesota Multiphasic Personality Inventory (MMPI):
  • Instrument used to develop pain profiles.
• Conditions that increase the perception of pain:
  • Depression and anger suppression.
  • Anxiety disorders, substance use disorders, and other psychiatric problems.

Pain Control

• Area that once hurt does not hurt anymore.
• Person feels sensation but not pain.
• Person feels pain but is not concerned about it.
• Person is still hurting but is able to tolerate it.

Pharmacological Control of Pain

• Administration of drugs.
• Types of drugs:
  • Local anesthetics: Affect the transmission of pain impulses from peripheral receptors to the spinal cord.
  • Spinal blocking agents.
  • Antidepressants: Affect the downward pathways from the brain that modulate pain.
• Drawbacks:
  • Undesirable side effects.
  • Addiction.

Surgical Control of Pain

• Disrupts the transmission of pain from the periphery to the spinal cord.
• Interrupts the flow of pain sensations from the spinal cord upward to the brain.
• Drawbacks:
  • Effects are short-lived and very expensive.
  • Surgery damages the nervous system.

Sensory Control of Pain

• Counterirritation: Inhibiting pain in one part of the body by stimulating or mildly irritating another area.
• Exercise and other ways of increasing mobility help the chronic pain patient.

Psychological Control of Pain

• Requires patients to actively participate and learn.
• More effective for managing slow-rising pains.

Biofeedback

• Providing biophysiological feedback to a patient about some bodily process of which the patient is unaware.
• Target function to be controlled is identified and tracked by a machine.
• Patient attempts to change the bodily process with the help of continuous feedback.

Relaxation Techniques

• Shifting the body into a state of low arousal by progressively relaxing different parts of the body using controlled breathing.
• Beneficial physiological effects are due to the release of opioids.

Distraction

• Turning attention away from pain by:
  • Focusing on an irrelevant and attention-getting stimulus.
  • Distracting oneself with a high level of activity.
• Most effective for coping with low-level pain.

Coping Skills Training

• Helps chronic pain patients manage pain.
• Expected duration of pain determines which coping strategy a patient should be trained in.

Cognitive-Behavioral Therapy

• Encourages patients to reconceptualize a problem from overwhelming to manageable.
• Patients:
  • Believe that the required skills will be taught to them.
  • Become competent individuals by aiding in the control of pain.
• Learn to break up maladaptive behavioral syndromes.
• Learn to make adaptive responses to pain.
• Are encouraged to attribute their success to their own efforts.
• Are taught relapse prevention.
• Are trained to control their emotional responses to pain.

Pain Management Programs

• Interdisciplinary efforts, bringing together neurological, cognitive, behavioral, and psychological expertise concerning pain.
• Steps:
  • Initial evaluation.
  • Individualized treatment.
• Components:
  • Patient education.
  • Involvement of family.
  • Relapse prevention.

Figure 10.2: The Experience of Pain

• The signal from the injured arm travels to the spinal cord, where it passes immediately to a motor nerve connected to the arm muscle. This causes a reflex action that does not involve the brain.
• Pressure, heat, or the release of chemicals from a damaged cell can be sources of this stimulation.
• The signal also goes up the spinal cord to the thalamus, where the pain is perceived.