Types of Pain & Management.

Pain is a feeling triggered in the nervous system. Pain may be sharp or dull. It may come and go, or it may be constant. You may feel pain in one area of your body, such as your back, abdomen or chest, or you may feel pain all over, such as when your muscles ache from the flu.

Pain can be helpful. Without pain, you might seriously hurt yourself without knowing it, or you might not realize you have a medical problem that needs treatment. Once you take care of the problem, pain usually goes away. However, sometimes pain goes on for weeks, months or even years. This is called chronic pain. Sometimes chronic pain is due to an ongoing cause, such as cancer or arthritis. Sometimes the cause is unknown.

Types of Pain :

Pain experts have divided the physical causes of pain into two types: nociceptive and neuropathic pain. The differences are important for understanding the nature of the pain problem and especially for determining how to treat the pain.

1. NOCICEPTIVE PAIN - Examples include sprains, bone fractures, burns, bumps, bruises, inflammation (from an infection or arthritic disorder), obstructions, and myofascial pain (which may indicate abnormal muscle stresses).

Nociceptors are the nerves which sense and respond to parts of the body which suffer from damage. They signal tissue irritation, impending injury, or actual injury. When activated, they transmit pain signals (via the peripheral nerves as well as the spinal cord) to the brain. The pain is typically well localized, constant, and often with an aching or throbbing quality. Visceral pain is the subtype of nociceptive pain that involves the internal organs. It tends to be episodic and poorly localized.

Nociceptive pain is usually time limited, meaning when the tissue damage heals, the pain typically resolves. (Arthritis is a notable exception in that it is not time limited.) Another characteristic of nociceptive pain is that it tends to respond well to treatment with opioids.

2. NEUROPATHIC PAIN - Examples include post herpetic (or post-shingles) neuralgia, reflex sympathetic dystrophy / causalgia (nerve trauma), components of cancer pain, phantom limb pain, entrapment neuropathy (e.g., carpal tunnel syndrome), and peripheral neuropathy (widespread nerve damage). Among the many causes of peripheral neuropathy, diabetes is the most common, but the condition can also be caused by chronic alcohol use, exposure to other toxins (including many chemotherapies), vitamin deficiencies, and a large variety of other medical conditions--it is not unusual for the cause of the condition to go undiagnosed.

Neuropathic pain is the result of an injury or malfunction in the peripheral or central nervous system. The pain is often triggered by an injury, but this injury may or may not involve actual damage to the nervous system. Nerves can be infiltrated or compressed by tumors, strangulated by scar tissue, or inflamed by infection. The pain frequently has burning, lancinating, or electric shock qualities. Persistent allodynia, pain resulting from a nonpainful stimulus such as a light touch, is also a common characteristic of neuropathic pain. The pain may persist for months or years beyond the apparent healing of any damaged tissues. In this setting, pain signals no longer represent an alarm about ongoing or impending injury, instead the alarm system itself is malfunctioning.

Neuropathic pain is frequently chronic, and tends to have a less robust response to treatment with opioids, but may respond well to other drugs such as anti-seizure and antidepressant medications. Usually, neuropathic problems are not fully reversible, but partial improvement is often possible with proper treatment.

3. MIXED CATEGORY PAIN - In some conditions the pain appears to be caused by a complex mixture of nociceptive and neuropathic factors. An initial nervous system dysfunction or injury may trigger the neural release of inflammatory mediators and subsequent neurogenic inflammation. For example, migraine headaches probably represent a mixture of neuropathic and nociceptive pain. Myofascial pain is probably secondary to nociceptive input from the muscles, but the abnormal muscle activity may be the result of neuropathic conditions.

MEDICATIONS FOR MANAGING PAIN

Common pain relievers - Nonaspirin pain relievers such as acetaminophen (Tylenol®) can relieve headaches and minor pain but do not reduce swelling. They are sometimes used in combination with other drugs to provide greater pain relief.
Anti-inflammatory drugs - Aspirin (Anacin®, Bayer®), coated or buffered aspirin (Ascripton®, Bufferin®) and aspirin with acetaminophen (Excedrin®) may be used to reduce swelling and irritation as well as to relieve pain.
There also are non-steroidal anti-inflammatory drugs (NSAIDs, commonly called "N-sayeds") such as ibuprofen (Advil®, Motrin®) and naproxen (Aleve®). Anti-inflammatory drugs are used to relieve pain, inflammation and fever.
There also are steroidal drugs (like cortisol and prednisone), available only by prescription, that are used to treat more serious inflammatory conditions such as chronic arthritis.

Opioid pain medications - Morphine-like drugs called opioids are prescribed to treat acute pain or cancer pain. They are occasionally used for certain chronic, noncancer pain as well.

Anti-depressants - These drugs were originally used only to treat depression. Studies now show, however, that they also can relieve certain pain. Available only by prescription, they often are used to help you sleep better at night.

Anti-seizure medicines - These medications are used to relieve what some patients describe as "shooting" pain by decreasing abnormal painful sensations caused by damaged nerves.

Other medicines - The doctor may also prescribe other types of medication that will be helpful for your specific pain problems. In addition, medications that counteract the side effects of opioids or treat the anxiety and depression associated with pain may also be prescribed.

TREATMENTS FOR MANAGING PAIN

Medication alone may not be enough to manage certain kinds of pain. Some medicines are more effective in fighting pain when they are combined with other methods of treatment. In some cases, the patient's pain condition may respond to treatment instead of medication. In fact, for some patients, certain therapies may eventually replace the need for taking any pain medicine, or less of it, over time. Here are just some of the available treatments being used successfully to treat pain patients.

Injection treatments - Local anesthetics (such as Novocain®), with or without cortisone-like medicines, can be injected around nerve roots and into muscles or joints. These medicines reduce swelling, irritation, muscle spasms and abnormal nerve activity that can cause pain.

Nerve blocks - Often a group of nerves, called a plexus or ganglion, that causes pain to a specific organ or body region can be blocked with local anesthetics. If successful, another solution that numbs the nerves can then be injected.

Physical and aquatic therapy - The physiatrist or physical therapist may suggest an exercise program tailored for you that will increase your daily functioning and decrease your pain. Other treatments may include whirlpool therapy, ultrasound and deep-muscle massage.

Electrical stimulation - Transcutaneous electrical nerve stimulation (TENS) is the most common form of electrical stimulation used in pain management. It is not painful and does not require needles or medicine. TENS consists of a small, battery-operated device that can diminish pain by stimulating nerve fibers through the skin.

Acupuncture - This ancient Chinese practice uses very thin needles at very specific points on the skin to treat disease and pain. Practitioners of acupuncture undergo specialized training in these techniques and may offer this treatment for certain painful conditions.

Psychological support - Many patients who are in pain feel the emotional effects of suffering along with the physical aspects of pain. These may include feelings of anger, sadness, hopelessness or despair. In addition, pain can alter one's personality, disrupt sleep, interfere with work and relationships and often have a profound effect on family members. Support and counseling from a psychiatrist or psychologist, combined with a comprehensive pain treatment program, may be needed to help you manage your condition. These trained professionals also can teach you additional self-help therapies such as relaxation training or biofeedback to relieve pain, lessen muscle spasms and reduce stress.

Surgery - When necessary, surgical treatment may be recommended. In rare instances when severe pain has not responded to other treatments and procedures, surgery on certain nerves can be done to give the patient some relief and allow them to resume near-normal activities. Usually all other avenues of treatment are tried before surgery is considered.

References:
1.http://www.nlm.nih.gov/medlineplus/pain.html#cat3
2.http://www.helpforpain.com/arch2000dec.htm
3.http://www.asahq.org/patientEducation/managepain.htm