those not at risk who may have similar diminished re-
sponsiveness is lacking as of 2001.
A third respiratory regulation control mechanism
is the arousal response. When experiencing hypocar-
bia or hypoxia, a normal sleeping infant will arouse
and increase respiratory efforts in response to this
life-threatening situation. Infants lacking sufficient
arousal responsiveness will continue sleeping,
becoming progressively more hypoxic, resulting in
cardiorespiratory failure and sudden death.
Other mechanisms that are thought to be associ-
ated with the occurrence of SIDS include abnormal
cardiac rhythms and increased body and/or environ-
mental temperatures. It is likely that the pathophy-
siology of SIDS involves complex interactions
between abnormal regulatory control systems and ep-
idemiological risk factors such as poor intrauterine
growth, exposure to smoking, prone sleep position-
ing, and prematurity.
Management
When a previously healthy infant is found unex-
pectedly dead, it is intensely emotionally traumatic.
Caregivers blame themselves and each other. Fami-
lies can be torn apart as a result of such an experi-
ence. For these reasons, proper management by
experienced professionals is essential. A thorough in-
vestigation to determine the true cause of death is re-
quired. Other causes of sudden unexpected deaths of
infants that have been mistakenly labeled as SIDS in-
clude congenital abnormalities of the heart and brain,
metabolic disorders, occult infection (an infection
that had escaped discovery), and accidental and non-
accidental trauma. Nonaccidental trauma or child
abuse mistaken for SIDS has been highlighted by sev-
eral high-profile cases in both the United States and
Europe. The recommended approach when an infant
is found unexpectedly dead consists of a thorough in-
vestigation at the scene to detail the environmental
circumstances. This should be followed by a careful
review of the infant’s medical, social, and family histo-
ries, followed by a complete postmortem examination
by an experienced forensic pathologist. In some
cases, laboratory studies on family members may be
indicated. Counseling of parents is essential so that
they have accurate information as to the cause of their
infant’s death and the implications for future chil-
dren, as well as for emotional support. Community
resources should be provided for ongoing support.
Prevention
Although a definitive cause of SIDS remains un-
known and there are no methods to predict which in-
fants will die from SIDS, parents should be educated
about strategies that will lessen the likelihood of a
SIDS event. Parents should be advised to place infants
on their backs for sleeping, provide a firm mattress,
avoid loose clothing and blankets in the crib, avoid
overheating their infant, breast-feed, and take their
infant for regular medical care.
See also: INFANCY; INFANT MORTALITY
Bibliography
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(2001):437–441.
Back to Sleep Campaign. ‘‘Reduce the Risk of Sudden Infant Death
Syndrome (SIDS)’’ (brochure). Washington, DC: Back to
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Butlerys, Marc G., Sander Greenland, and Jess Kraus. ‘‘Chronic
Fetal Hypoxia and Sudden Infant Death Syndrome: Interac-
tion between Maternal Smoking and Low Hematocrit during
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Hunt, Carl E. ‘‘Sudden Infant Death Syndrome.’’ In Waldo E. Nel-
son ed., Nelson Textbook of Pediatrics. Philadelphia: Saunders,
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Jeffery, Heather, Angelique Megevand, and Megan Page. ‘‘Why
the Prone Position Is a Risk Factor for Sudden Infant Death
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Klonoff-Cohen, Hillary S., Sharon L. Edelstein, Ellen Lefkowitz,
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Smoking and Tobacco Exposure through Breast Milk on Sud-
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Carol A. MillerSUICIDE
Suicide is defined as the deliberate killing of oneself.
Tragically, suicide is a problem that affects people of
all ages, but most dramatically, adolescents and
young adults. In fact, suicide is the most rapidly grow-
ing cause of death among youth between the ages of
fifteen and twenty-four. In the mid-1990s, the Na-
tional Center for Health Statistics ranked suicide as
the third-leading cause of adolescent death, as it
claimed the lives of approximately 5,000 American
teenagers and young adults. In addition, the number
of recorded deaths by suicide is apparently an under-
estimate of reality since a large number of completed
suicides go unreported or are labeled as accidents.
Suicide attempts are defined as intentional, self-
inflicted, and life-threatening acts that do not result396 SUICIDE