Pain
Modified: 2024-06-19 10:53 AM CDST
- The receptors for pain are free nerve endings in the skin.
- Those free
nerve endings cover most but not all of the skin.
- So, it is possible
to find parts of your skin that do not respond to pain.
- Billions of dollars are spent each year to treat pain as a
symptom.
- Much of that money is spent on:
- Behavioral management is also used.
- The environment can affect pain.
- During World War II surgeons
found that soldiers required much less morphine than prewar civilian
patients did.
- Doctors attributed that difference to the differences in
perception of both groups.
- To civilians, going to the hospital is an
unwelcome experience and they expect pain.
- However, to soldiers in
battle, going to the hospital is a welcome experience.
- Their feelings
are of relief, not of dread.
- So, pain can be affected by the
environment, and that probably forms the basis for behavioral
treatments for pain.
- The physiology of pain is has been described by gate theory.
- In
gate theory, two types of pain pathways are proposed.
- One type
conducts the pain impulse quickly, the other slowly.
- They both come
into a "gate."
- Usually we cannot prevent the fast-acting pain from
being detected.
- However, gate theory says that if the gate is
stimulated, say by rubbing, then the slow-acting pathway will be
closed.
- Take the following example.
- You hit your thumb with a hammer by
accident.
- Then you quickly rub your thumb. By doing that you may
close the slow-acting pathways, and not feel throbbing pain in your
thumb later.
- Drugs that relieve pain are called analgesics.
- Aspirin and tylenol
are analgesics.
- So is morphine, a very powerful analgesic.
- Unfortunately, morphine also has addictive properties.
- Endorphins are
analgesics manufactured by the body.
- They are produced in response to
pain and they may account for individual differences in pain
perception.
- One person may just produce more endorphins than another
in response to the same painful stimulus, and thus report less pain.
- Anesthetics are drugs that deaden all of the skin senses.
- When you go
to the dentist for a tooth extraction or cavity, you will get an
anesthetic, novacaine.
- Novacaine causes you not to feel pain, touch,
hot, or cold.
- So, when you attempt to put a little water into your mouth to rinse it, you cannot
keep your lips on the cup easily, or feel the cup.
- I was shocked when
a surgeon once injected me with xylocaine, (a fast-acting anesthetic) and immediately picked up his
scalpel.
- I thought he would wait awhile, but he assured me he did not
need to, and proceeded to remove a small abscess, without my feeling
anything.
- I watched as he painlessly cut my arm, bled, and later sutured the wound.
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