PAIN

Definition of PAIN
 It is an unpleasant sensory and emotional experience associated with actual or potential tissue damage.

 Pain is highly subjective and individual and it is the body’s defense mechanism indicating that there is a problem.

Types of Pain
Pain is described in terms of

 Location
 Duration
 Origin
 Cause / physiologic basis

Location in the body :

 Radiating pain: it is perceived from the source of the pain and extends to near by tissues. Eg cardiac pain

 Referred pain: pain from one part of the abdominal viscera may be perceived in an area of the skin remote from the organ causing pain
 Intractable pain: which is highly resistant to relief
eg: Pain in advanced malignancy

 Neuropathic pain: due to result of disturbance of the peripheral CNS, which is often severe
(shooting or stabbing pain)‏

 Phantom pain: painful sensation perceived in a part of the body that is missing


According to Origin:

 Cutaneous pain: sharp pain arising from skin and subcutaneous tissue

 Deep somatic pain: diffuse pain arising from ligaments,tendons,bones,blood vessels and nerves eg: sprain

 Visceral pain: due to stimulation of pain receptors in the abdominal cavity, cranium and thorax
eg: burning aching feeling of pressure caused by muscle spasm in obstructed bowel

According to Duration:

 Acute pain - lasts upto 6 months
- sudden & slow onset
- mild to severe pain

 Chronic pain - lasts more than 6 months
- difficult to relieve
- eg. Chronic malignant pain

Comparison of acute & chronic pain
Acute pain

 Warns of injury
 Recent onset
 Mild –severe
 Lasts few seconds to 6 months
 Anxiety follows

eg. Surgical interventions, trauma

Chronic pain

 No purpose
 Continuous/ intermittent
 Mild – severe
 Lasts long 6 months and more
 Depression follows

eg. cancer, arthritis, trigeminal neuralgia

Responses to pain

Acute pain:

 Increased Pulse rate
 Raised BP/ fall in BP & shock
 Increased respiration
 Dilated pupils
 Diaphoresis
 Muscle tension
 May rub, cry / hold area
 Reports pain
 Reduced GI motility

Chronic pain:

 Vital signs –usually normal
 Pupils normal or dilated
 Dry or warm skin
 Depression, irritability
 Withdrawal from interests & relationships
 Disturbed sleep
 Reduced libido
 Reduced appetite

According to the physiologic basis of pain

 Mechanical - trauma
- blockage of body duct
- tumor
- muscle spasm

 Thermal - extreme heat or cold
 Chemical - Tissue ischemia --> Blocked artery --> stimulation of pain receptors --> accumulation of lactic acid