Wrapping or bracing an injured JOINTor limb pro-
vides support during activity. Ice to the affected
area soothes INFLAMMATION, slowing the release of
prostaglandins and other biochemicals that stimu-
late the pain response. Heat and therapeutic mas-
sage help tight, stiff muscles relax and improves
BLOODflow to the HEALINGarea. Alternating heat
and ice can provide substantial relief for muscu-
loskeletal pain.
See alsoANESTHESIA; DERMATOME; EYE PAIN; MAS-
SAGE THERAPY; NEURORECEPTOR; PATIENT CONTROLLED
ANALGESIA(PCA); TERMINAL PAIN.
aging, changes in pain perception that occur
with The perceptions of PAINand the responses
to pain relief methods change across the spectrum
of age. A long-held belief is that infants experi-
ence pain only in the most rudimentary fashion;
current research shows that infants experience
nearly the same range and nature of pain as do
adults. They also have the capacity to remember
pain experiences. Children of all ages have sur-
prisingly sophisticated understanding of pain and
pain relief. At the other end of the spectrum, for
about a third of people over age 60 pain is a daily
experience. But as the body ages its ability to
respond to ANALGESIC MEDICATIONS and other
approaches to pain relief changes. So does its abil-
ity to generate its own natural pain relievers,
endorphins and enkephalins.
Pain in Infants and Children
Though an infant’s NERVOUS SYSTEMcontinues to
develop after birth, the mechanisms for nocicep-
tion (stimulation of nerves to transmit pain signals
to the CENTRAL NERVOUS SYSTEM) are capable of
function at about 28 weeks of gestational age—12
weeks before a full-term delivery. Though infants
under age 12 months cry when in pain and
exhibit reflexive behaviors to avoid painful stim-
uli, it is difficult to determine the severity of the
pain. Young children (ages 1 to 5 years) are able to
assess the severity of their pain and convey this to
caregivers. A common pain scale for young chil-
dren is the Wong-Baker Faces Scale, which uses a
series of smiling-to-frowning faces for children to
describe how their pain feels. Other pain assess-
ment scales make use of the child’s physical
behaviors and degree to which the child responds
to comforting measures to help caregivers assess
the level of pain the child is experiencing.
Because a child’s body is not fully developed, it
metabolizes medications differently from that of
an adult’s body. Analgesic medications to relieve
pain thus have different therapeutic levels, dura-
tions of effectiveness, and toxic levels. Some anal-
gesics have undergone clinical study to quantify
their actions and side effects in children though
many have not. Pediatric dosing for analgesics is
sometimes imprecise and tends to err on the side
of undertreating pain in children. Children who
have significant or CHRONIC PAIN should receive
care from pediatric pain specialists to ensure that
they receive adequate pain relief.
Pain in the Elderly
The number of peripheral sensory receptors grad-
ually diminishes with aging, affecting the PERIPH-
ERAL NERVOUS SYSTEM’s ability to detect pain and
convey pain signals to the central nervous system.
This can result in more serious injury before there
is adequate stimulus to avoid the situation. An
older person may experience scalding and damage
to the SKINfrom water that is too hot, for example,
before nociceptors detect the danger. Sensory
receptors, including nociceptors, are also more
susceptible to dysfunction and may overrespond
to stimuli, resulting in MALDYNIA.
Other changes that take place in the body affect
the METABOLISMof drugs, which in many circum-
stances means that less of the medication is neces-
sary to achieve the desired therapeutic effect. The
body may take longer to clear the medication,
meaning doses should be farther apart (such as
every six hours instead of every four hours) or that
the DRUGmay more quickly accumulate to a level of
toxicity. Changes in gastric acid production and
STOMACHfunction make the lining of the stomach
more vulnerable to damage from highly acidic
products, increasing the risk of bleeding with acidic
medications such as ibuprofen and aspirin. Because
of this the American Geriatric Society recommends
that most people over age 65 take acetaminophen
as the first choice for mild to moderate pain relief.
Because older people are more likely to have
health conditions that require regular medications,
364 Pain and Pain Management