Management and Measurement of Pain 

Whats is Pain,Classification of Pain,Gate Control Theory,Involvement of Genetics and Production of Neurotransmitter,Pharmacological Interventions,Non Pharmacological Interventions or Physical Modalities,Psychological Modalities.

Whats is Pain

    Pain is “an unpleasant sensory and emotional experience associated
with actual or potential damage or described in terms of such damage; pain is
always subjective” (International Association for the Study of Pain, 1979, p.
250). 

    People in pain not only suffer considerably but are at risk for long term
adverse effects. Pain is a common component of illness and is the most common
reason that people seek medical attention. 

    People experience pain in different
ways and only those who have the pain know what it is really like,
Communication of that pain to caregivers is dependent on the verbal abilities
of the patient, with those who are very young and those who are cognitively
impaired being at risk for misunderstanding of its effects.

Classification of Pain

    Pain generally is classified into two types: acute and chronic.
However, there are many different types and causes of pain. TL. acute pain
following surgery and injury 473/832 during labor, sickle cell crisis, and health
care procedures. 

    Chronic pain can occur in the Musculoskeletal system, the
gastrointestinal system, and the urinary system, and can be recurrent or
constant. Cancer pain is from the enlarging tumor, its metastases, or its
treatment and is often chronic, increases in intensity and extent; Also, acute
pain can break through the usual pain. 

    Some types of pain are classified by the
context in which they occur. These include pain in infants, the critically ill,
the cognitively impaired, and at the end of life. 

    Acute pain subsides as
healing takes place. Acute pain has a predictable end and is of brief duration,
usually less than 3 to 6 months. Chronic pain is said to be that which lasts
for longer.

    The undertreatment of pain has been well documented for at least
the past 30 years (Marks & Sachar, 1973). Barriers to the effective
treatment of pain include clinicians’ lack of knowledge of pain management
principles, clinician and patient attitudes toward pain and drugs, and overly
restrictive laws and regulations regarding use of controlled substances. 

    The
undermanagement of pain has been particularly pronounced in children, the
elderly, and those who cannot speak. Pain relief in palliative care and at the
end of life is receiving increased attention in research and practice.

Gate Control Theory 

    The gate control theory published by Melzack and Wall (1965)
provided a theoretical basis for showing how pain, transmitted peripherally to
the brain, can be influenced by cognitive and affective as well as
physiological factors. 

    Theories of pain have evolved in recent years to the
idea of a mind body unity that Melzack (1996) calls a neuro matrix. An active
brain is part of a whole person who has been shaped by genetics and learning to
respond to noxious stimuli in individually characteristic patterns. 

Involvement of Genetics and Production of Neurotransmitter

    Recent
studies of the role of genetics, endorphins, and immune factors, imaging
studies of the thalamus, the anterior cingulate, the limbic system, and the
cortex, support a holistic theory that goes i beyond the mechanics of
transmission of noxious messages.     An appreciation of the mind-body experience
of pain provides a basis for multidisciplinary research and practice,
multicultural responses, and multimodal strategies for managing pain. 

    Within
the neuromatrix of a whole and active person, tissue damage causes the release
of pain producing substances, such as serotonin, histamine, bradykinin and
substance P, which stimulate nerve endings called nociceptors. 

    Action
potentials travel along the peripheral nervous system, are modified in the
dorsal horn of the spinal cord, and travel to the brain where sensory, affective,
and cognitive responses occur. 

    Nerve fibers descending from the brain to the
dorsal horn can inhibit the perception of pain. Opiate receptors in the brain
or spinal cord react both to opiates that are externally administered and to
enkephalins and endorphins produced by one’s own body to modulate pain. 

    Pain
management includes pharmacological, cognitive-behavioral, physical, radiation,
anesthetic, neurosurgical, and surgical techniques. Analgesics administered
orally or intravenously are needed for moderate to severe pain, and
cognitive-behavioral techniques such as relaxation, music, and distraction can
increase the relief. 

    More complex pain, such as that experienced by patients
with reflex sympathetic dystrophy or by cancer patients who have unrelieved
pain from several origins as well as neurogenic and breakthrough pain, may
require evaluation and treatment by a multispecialty pain management team. 

    The
successful management of pain generally depends on a careful assessment of the
pain, patient education for pain management, appropriate pharmacological and
nonpharmacological intervention, reassessment to determine the effectiveness of
interventions used, and reintervention until satisfactory relief is obtained
(Good, 2003) .

Pharmacological Interventions

    Pharmacological management of pain usually is treated by three
types of drugs: 

(a) aspirin, acetaminophen, and nonsteroidal anti-inflammatory
drugs (NSAIDS)

(b) opioids

(c) adjuvant analgesics

    NSAIDS decrease the
levels of inflammatory mediators generated at the site of tissue injury, thus
blocking painful stimuli. They are useful in the management of mild pain and
may be used in combination with opioids for moderate to severe pain. Opioids
are morphine like compounds that produce pain relief by binding to opiate
receptors. 

    They are used with moderate and severe pain and can be administered
orally, subcutaneously, intramuscularly, intravenously, rectally, transdermal,
epidurally, nasally, intraspinal, and intraventricularly. 

    Patient controlled
analgesia (PCA) can be accomplished by mouth or by use of equipment set to
prescribed parameters to administer a drug intravenously, subcutaneously, or
epidurally. Adjuvant drugs are used to increase the analgesic efficacy of
opioids, to treat other symptoms that exacerbate pain, or to provide analgesia
for specific types of pain.

Non Pharmacological Interventions or Physical Modalities 

Physical modalities for pain management include use of heat and
cold, counter stimulation such as transcutaneous electrical nerve stimulation
(TENS), and acupuncture. 

    Cognitive techniques are focused on perception and
thought and are designed to influence interpretation of events and bodily
sensations. Providing information about pain and its management, helping
patients think differently about pain, and distraction strategies are examples
of cognitive techniques. 

    Behavioral techniques are directed at helping patients
develop coping skills and modify their reactions to pain. Cognitive behavioral
techniques commonly used by nurses and other clinicians include relaxation,
music, imagery, distraction, and reframing. Psychotherapy, support, and
hypnosis also have been used successfully in pain management.

Psychological Modalities 

When the use of drugs, with or without physical and cognitive
behavioral modalities, is not adequate to manage pain, other management
techniques may be used. These depend on the cause of the pain and may be
temporary or permanent. 

    Radiation therapy is used to relieve metastatic pain
and symptoms from local extension of primary disease. Nerve blocks include the
injection of a local anesthetic into a spinal space and peripheral nerve
destruction. 

    Surgical procedures are used to remove sources of pain, such as
debulking a tumor that is pressing on abdominal organs or removing bone spurs
that are compressing nerves, Neuro ablation techniques include peripheral
neurectomy, dorsal rhizotomy, cordotomy, commmissural myelotomy, and
hypophysectomy. 

    In recent years, various agencies and organizations have
published guidelines for the management of pain. These have included guidelines
published by the Agency for Health Care Policy and Research on the management
of acute pain, cancer pain, and low back problems. 

    In addition there are three
books from the American Pain Society (APS): on analgesic use, guidelines for
pain in arthritis, and pain in sickle cell disease. 

    In the near future APS will
publish two new guidelines for cancer pain and for fibromyalgia. The Joint
Commission for Accreditation of Healthcare Agencies has included policies and
procedures for pain management in their standards. 

    Pain relief is a patient’s
right, but there is greater consensus regarding management of acute and cancer
pain than for chronic nonmalignant pain.