Chronic Pain

What is pain? A sensory and emotional experience of discomfort. Single most common medical complaint.

Qualities of Pain Organic vs. psychogenic Acute vs. chronic Malignant or benign Continuous or episodic

Perceiving Pain Algogenic substances – chemicals released at the site of the injury Nociceptors – afferent neurons that carry pain messages Referred pain – pain that is perceived as if it were coming from somewhere else in the body

Three Chronic Pain Conditions Neuralgia – an extremely painful condition consisting of recurrent episodes of intense shooting or stabbing pain along the course of the nerve. Causalgia – recurrent episodes of severe burning pain. Phantom limb pain – feelings of pain in a limb that is no longer there and has no functioning nerves.

Gate-Control Theory – Ronald Melzack (1960s) Described physiological mechanism by which psychological factors can affect the experience of pain. Neural gate can open and close thereby modulating pain. Gate is located in the spinal cord.

Gate-Control Theory of Pain Experience of pain depends (in part) on whether the pain impulse gets past neurological “gate” in the spinal cord and thus reaches the brain.

Conditions that Open the Gate Physical conditions Extent of injury Inappropriate activity level Emotional conditions Anxiety or worry Tension Depression Mental Conditions Focusing on pain Boredom

Conditions That Close the Gate Physical conditions Medications Counter stimulation (e.g., heat, message) Emotional conditions Positive emotions Relaxation, Rest Mental conditions Intense concentration or distraction Involvement and interest in life activities

Neuromatrix Theory of Pain Theory that the matrix of neurons in the brain is capable of generating pain (and other sensations) in the absence of signals from sensory nerves.

The Withdrawal Reflex

Four Types of Pain Behaviours Facial/audible expression of distress Distorted ambulation or posture Negative affect Avoidance of activity

Emotions, Coping, and Pain Chronic pain is associated with higher levels of anger, fear, sadness, anxiety and stress.

Question: What happens to a person's pain when the cognitive coping process is learned? Do you think that this is real or not? Can it help or is it just a way to trick the mind? Explain your answer.

Treatment of Chronic Pain Surgical procedures to block the transmission of pain from the peripheral nervous system to the brain. Synovectomy – Removing membranes that become inflamed in arthritic joints. Spinal fusion – joins two or more adjacent vertebrae to treat chronic back pain.

Pharmacologic Control of Pain About half of hospitalized patients who have pain are under-medicated. Children are at particular risk of poor pain control methods. Medications are given as: PRN – “as needed” As a prescribed schedule

Types of Pain Medications Peripherally active analgesics – work at the periphery (e.g., aspirin, Tylenol). Centrally active analgesics – narcotics that bind to the opiate receptors in the brain (e.g., codeine, morphine, heroin). Local analgesics – can be injected into the site of injury or applied topically (e.g., novocaine). Indirectly acting drugs – affect non-pain conditions such as emotions that can exacerbate pain experience.

Psychological Pain Control Methods Biofeedback – provides biophysiological feedback to patient about some bodily process the patient is unaware of (e.g., forehead muscle tension). Relaxation – systematic relaxation of the large muscle groups. Hypnosis – relaxation + suggestion + distraction + altering the meaning of pain.

Psychological Pain Methods Acupuncture – not sure how it works. Could include: Counter-irritation – may close the spinal gating mechanism in pain perception. Expectancy Reduced anxiety from belief that it will work. Distraction Trigger release of endorphins

Question: There are many alternative ways to deal with pain in our society today. To name a few, we have biofeedback, hypnosis, acupuncture, and laughter. These alternative forms of dealing with pain work. What would make these specific methods work on pain? Take each one and describe in detail how the concept would work with pain. We will discuss this individually in seminar.

Questions How would you describe a person with a Pain Prone Personality? What do they receive out of pain that they might not receive without pain?

Wrap Up Are there any questions that I missed? Do you have any other comments or questions you would like to ask? Have a wonderful week!