Pain Management

Pain is a normal, predicted physiological response to an adverse chemical, thermal, or mechanical stimulus associated with surgery, trauma, and acute illness. It is generally time-limited and is responsive to Opioid therapy, among other therapies.

Definition

The international association for the study of pain (IASP) defined pain as an unpleasant  sensory and emotional experience associated with actual or potential tissue damage or it is described in terms of such damage.

Nature of pain

• Clinical pain is subjective and no objective measures of it exists, the only people who can accurately define their own pain are experiencing that pain.
• Pain is a protective physiological mechanism. E.g.: a person with a sprained ankle avoids bearing full weight on the foot to prevent further injury.
• Pain is a warning that tissue damage has occurred.
• Pain is a leading cause of disability.

Types of pain

There are different ways to define types of pain, which include according to onset, duration, severity, modes of transmission, location, causation and causative forces.

• Onset or time of occurrence. e.g.: postoperative pain.
• Duration. e.g.: chronic pain or acute pain
• Severity or intensity. E.g.: severe, mild or scored (0 to 10 a scale )
• Location or source. e.g.: superficial, deep or central pain
• Causation. E.g.: pain due to receptor stimulation or nerve damage or psychophysiologic pain
• Causative force or agent. E.g.: spontaneous, self inflicted or other pain.

Acute pain

• Recent onset and is most commonly associated with a specific injury.
• It is time limited and has a defined cause and purpose.
• It may be mild, moderate or severe in nature and sudden in onset.
• It occurs after an injury or disease, persists until healing occurs.

Chronic pain

• Is a complex physiological and psychological phenomenon that causes varying degrees of disability in a larger portion.
• It is constant or intermittent in nature that persist over a period of time.
• It is often can not be attributed to a specific cause or injury.
• It may lasts for six months or larger.
• Classified as malignant or non malignant.

Superficial pain

• It occurs when receptors in surface tissues are stimulated.
• Classified into 2 types
• Pain with an abrupt onset and a sharp or stinging quality.
• Pain with a slower onset and burning quality.
• It may be delineated by having the client point to the painful area.
• It is relatively uncomplicated because it is readily localized , that is, which client can indicate exactly where it hurts.

Deep pain

• Deep pain arises from deep tissues.
• It is divided automatically into splanchnic which refers to pain in the viscera and deep somatic referring to pain in deep structures  other than the viscera such as muscle, tendons, joints and periosteum.

Splanchnic pain:

• Viscera pain tends to be diffuse, poorly localized, vague, dull pain.
• Autonomic manifestations such as diarrhea, cramps, sweating, hypertension frequently accompany viscera pain.
• It includes acute appendicitis, cholecystities, inflammation of the biliary and pancreatic tract, gastro duodenal disease, cardiovascular disease, renal and ureteral colic.

Deep somatic pain:

• It is generally diffuse, less localizable than cutaneous pain. somatic structures vary in their sensitivity to pain.
• Highly sensitive structure include tendons, deep fascia, ligaments, joints, bone periosteum, blood vessels and nerve.
• Skeletal muscle is sensitive only in stretching and ischemia.

Localized pain

• It arises directly from the site of the disturbance.

Referred pain

• It is one which is felt in a part of the body which is remote from the actual point of stimulation.
• The impulses usually arise in an organ, but the pain is projected to a surface area of the body.
• E.g.: angina pectoris, the pain originates in the heart muscles, but it may be experienced in the mid-sternal region, the base of the neck and down to the left arm.

Intractable pain

• Persistent, severe pain that cannot be effectively controlled by the usual medication.
• It producing prolonged and intense bombardment of the central nervous system, are very difficult to bear.

Psychogenic pain

• It is experienced when there is no detectable organic lesion.
• It refers to pain that believed primarily due to emotional factors rather than physiologic dysfunction.
• Clients experiencing psychogenic pain have a real pain expereince.

Factors influencing pain

• Situation:
• The situation associated with the pain influence the person’s response to it.
• A person’s responses to pain experienced in a formal crowed situations may differ greatly from the responses were he or she alone or in a hospital.
• Culture:
• It influences how people learn to react to expressing pain.
• People responds to pain in different ways.
• A young girl may be allowed to cry because of pain whereas boys are not allowed to cry in some culture.
• Age:
• It is an important variable that influences pain particularly in children and older adults.
• Young children have difficulty in understanding pain.
• Older people may assign different meanings to that pain, it thought by the elderly as natural manifestation of aging.
• Sex:
• In most cultures boys are expected to show less expression of pain than girls.
• As they grow older men are also expected to express less pain than women.
• Meaning of pain:
• The meaning of a person’s pain is a factor that influence his or her responses to pain.
• For e.g.: pain caused by childbirth may be responded differently from pain caused by surgery.
• A client copes differently with pain depending on its meaning.
• Anxiety:
• When anxiety is high pain is felt greater.
• Emotionally healthy persons are usually able to tolerate moderate or even severe pain than those whole emotions are less stable.
• Fatigue:
• It heightens perceptions of pain.
• This intensifies pain and decreases coping abilities.
• Pain is often experienced less after a restful sleep than at the end of a long day.
• Attention:
• The degree at which a client focuses on pain can influence pain perception.
• Increased attention has been associated with increased pain, whereas distraction has been associated with a diminished pain response.
• Previous experience:
• Each person learns from painful experiences.
• Patient had repeated experience of pain may be better prepared to tolerate or take necessary actions to relieve pain to some extent.
• Coping style
• Family and social support

Assessment of Pain

• Pain assessment is one of the most common and difficult activities a nurse performs.
• Highly subjective.
• Need a good rapport with the person in pain.

Factors to consider in a complete pain assessment are

• The intensity.
• Timing.
• Location.
• Quality.
• Personal meaning.
• Aggravating and alleviating factors.
• Pain behaviors.

Pain Assessment Scales

• Visual Analogue Scale (VAS).
• Faces pain scale

Pain Management Strategies

• Pharmacological
• Non pharmacological measures

Pharmacological Methods

• Main drug forms are
• Balanced anesthesia/analgesia.
• Analgesics.
• Patient controlled analgesia.
• Local anesthetic agents.
• Opioid analgesic agents.

• Most effective when a multi modal approach is used.
• It refers to the use of more than one form of analgesia concurrently.
• Three general categories of analgesia are
• NSAID(non steroidal anti-inflammatory drugs)
• Opioids
• Local anesthetics
• PCA allows the self administration of drugs for chronic pain.
• Mainly used in cancer and POP cases.
• This approach can be used with oral analgesic agents  as well as continuous infusion of opioid drugs.
• Local anesthetics work by blocking nerve conduction when applied directly to the fibers.
• Topical application
• Intraspinal administration

Non Pharmacological Methods

• Cutaneous stimulation and massage.
• Cold and heat therapies.
• Trans Cutaneous Nerve Stimulation (TENS): It is a battery operated device with electrodes, applied to the skin to produce a tingling, vibrating or buzzing sensation in the area of pain. It decreases the pain by stimulating the non pain receptors of the site
• Distraction
• Relaxation techniques
• Guided imagery
• Hypnosis