Pathophysiology
•
Critical Periods of Development •
 Alcohol,
a known teratogen, readily crosses the placenta and enters the developing fetus.
The specific effect of maternal alcohol intake on the developing fetus is a
result of the interaction of the timing of the exposure, the dose or amount
of the substance imbibed by the mother, and the fetus' susceptibility to the
alcohol. There are critical periods of development that dictate which organ
system(s) may be most affected by prenatal alcohol use.
The
gestational term is divided into three distinct periods: the pre-differentiation
period of fertilization and implantation, the embryonic period, and the fetal
period. During the first week of gestation, fertilization occurs in the upper
third of the fallopian tube. Over the next seven days, the zygote (the product
of conception) makes its way down to the uterine cavity. It implants on or about
the seventh day after fertilization. During this time, cells are rapidly multiplying
through the process called mitosis. If there is an exposure to a teratogen,
the zygote will then respond in accordance with what some experts refer to as
the "all or nothing" principle: Either the zygote dies or it survives,
with no shades of moderate adverse effects. Death results from the cessation
of mitotic cellular division, and the zygote will not implant. If the zygote
dies the woman may never even know she was pregnant, although she may experience
a late period or a heavier than usual menstrual flow. The zygote that survives
may be so strong that there are no residual effects.
Alcohol
in the animal model has been shown to result in death of the developing
zygote. However, if implantation occurs, then the zygote has passed to
the embryonic stage. At this time, the germ layers are being laid down
to create all the organs and structures that will ultimately form the
fetus. In the animal model of FAS, an exposure to alcohol on day 7 or
8 of gestation adversely affects craniofacial development. The results
include micrognathia (small jaw), low-set ears, short philtrum (shortened
distance between the nose and mouth), and sometimes even a cleft palate
and lip. There may be microcephaly (small head circumference in relationship
to the chest and overall length) and various brain malformations. Alcohol
exposure on day 9 or 10 in animals results in urogenital defects, usually
urinary obstructions, as well as limb defects such as shortened or malformed
limbs. By week three of gestation, there is already a beating heart and
the structures are visible for the developing neurologic system. Weeks
4 to 8 of gestation are periods of great differentiation and growth of
organs, referred to as organogenesis. Any alcohol exposure at this
time may result in specific organ damage.
The
most rapidly growing organ system at any given time is the most vulnerable to
any type of insult. During the fetal period, arising from weeks 9 through term
or 40 weeks, alcohol exposure will affect the growth of the organs, and the
linear growth of the fetus. The cells that are growing the most rapidly, such
as those in the neurologic system, are the most vulnerable to damage. Slowed
brain cell growth increases the chances of mental retardation and cognitive
problems, as well as gross and fine motor impairment. Thus, no period of gestation
is safe for alcohol use.
Etiology/Triggering
Stimuli
•
Maternal Drinking Patterns •
Babies
with FAS or FAE are more likely to be born to women who are older and
who have had at least two or three prior pregnancies. The reason for this
maternal profile is due to the woman's drinking patterns. If she is truly
dependent or addicted to alcohol, its use will increase over time. Also,
there is a good likelihood that the mother's nutritional status will suffer
more as her alcohol intake increases. Chronic alcohol use is associated
with the development of a fatty liver or cirrhosis of the liver, which
affects the woman's metabolism. Her body is less able to clear the alcohol
from her system; thus the level of alcohol remains higher for a longer
period of time. The fetal alcohol level is usually several times higher
than the woman's level and stays higher longer, due to the absorption
of the alcohol into the fetal fatty tissues and the inability of the immature
fetal liver to excrete the alcohol. It is not unusual for the mother to
die of alcohol-related complications before her alcohol-exposed offspring
is four or five years old.
A
woman who is known to binge drink, and for the pregnant woman this is defined
as three or more drinks at one time, is more likely to produce a child with
FAS or FAE than a woman who does not binge. Other considerations are that alcohol
dependence and other substance use, including smoking, go hand and hand. Alcohol
can enhance the effects of other drugs, while the other drugs may diminish the
hangover from alcohol. Cocaine and other drugs are often used in conjunction
with alcohol, compounding the negative effects on the fetus. Use of substance
combinations along with alcohol has made it difficult in some instances to tell
which substance caused what effects in the newborn. From the nursing perspective,
an accurate prognosis for the child depends on the disclosure of all substances
that the mother is taking in her health history.
•
Genetic and Environmental Influences •
Sensitivity
to alcohol appears to be associated with certain configurations of maternal
genes or genotype; this may be true for the fetal genotype as well. Though there
are no specific genetic linkages known for alcoholism or alcohol metabolism,
it is an area of research currently being explored. Such linkages might explain
the differences in the degree of anomalies or physical or psychological/cognitive/behavioral
effects seen in neonates and children. Research has found that children with
FAS are at risk for the development of alcoholism at a later period in their
life. This finding lends credibility to the side in favor of genetic linkages.
It may be that the genes act to modify the effect of the alcohol on the developing
fetus. The opposing viewpoint is that children learn from observation of their
parents, and the use of alcohol is learned behavior. While either position may
be true, from the nursing perspective, the concern is not so much how the child
came to be at risk for later development of alcoholism, but rather that the
risk for alcoholism is greater in children born to alcoholic mothers.
The
environment may also play a role in the development of FAS or FAE in terms of
long-term effects. From this perspective, the focus is on the family and the
home environment. It is known that impaired neurobehavioral development is one
of the key features of FAS/FAE. When this is coupled with a potentially addicted
mother and a possibly dysfunctional family unit, it is then not surprising that
the home stability and family interactions with the neonate, infant, and child
can also be affected. If the parents are not sensitive to infant cues or are
absorbed in their own addiction, then little effort may be made to promote positive
development. Lack of parental interaction with the infant may further impede
cognitive and behavioral growth, thus exacerbating the effects of the alcohol
itself. It becomes a vicious cycle as the child may be restless, inattentive
and irritable, thus making it difficult for the parent to interact positively
with the child. The mother may be intolerant of these behaviors, leading to
an increase in her stress level that in turn may cause her to drink more alcohol
to cope. The child may also be at risk for child abuse or neglect. Nurses must
be adept at assessing parent-infant interactions in order to detect faulty parenting
skills, faulty attachment, and inappropriate interactions that might put the
child at risk.
Clinical
Manifestations
•
Dysmorphology of the Neonate •
The
neonate with true FAS will exhibit certain classic characteristics. These
include microcephaly (small head circumference in relationship to the
chest size and overall length), decreased linear growth, small size for
gestational age (often less than the 10th percentile for growth), craniofacial
anomalies, and neurobehavioral manifestations. The specific craniofacial
anomalies are midline facial defects. The eyes appear wide spaced; the
nasal bridge flattened (this feature may really be responsible for the
eyes appearing wide spaced as upon measurement the distance may be close
to that of a healthy infant); the nose upturned slightly; short palpebral
fissures or eye slits (another reason for appearance of wide spaced eyes);
smooth, short philtrum (area between nose and upper lip); and a thin upper
lip (vermillion border).
The
neurobehavioral manifestations include opisthotonos (hyperextension of
the body with the back arched upward), weak suck, disorganized sleep/wake
cycles, and difficulties in habituating. There may or may not be other
major organ system effects. The most common cardiac anomaly is ventricular
septal defect (VSD), and urinary obstructions may affect the genitourinary
system. Skeletal malformations may include abnormal palmar creases, camptodactyly
(crooked little finger) or clinodactyly (shortened little finger), and
hypoplastic finger or toenails.
The
classic triad of symptoms is growth retardation, the pattern of minor anomalies,
and some neurologic effects. This triad is usually used by physicians and dysmorphologists
(physicians who specialize in anomalies) to make the diagnosis. Although instrumentation
is being developed that would help identify FAS infants and children through
the use of a scoring tool, there are currently no standardized methods for diagnosing
FAS/FAE. Many physicians admit that the signs are so subtle that they are not
always able to make a definitive diagnosis. At times, the dysmorphic features
associated with FAS are not apparent at birth and even when they are, they often
fade over time.
•
Neurological Effects and Cognitive/Behavioral Manifestations •
The
primary effect of alcohol on the developing brain is to create faulty wiring
or cause short circuits in neurological function. Alcohol disrupts the normal
growth and migration of neural cells, leading to structural defects within the
confines of the brain. Upon autopsy of several fetal alcohol-exposed infants,
both the neuronal and glial portions of the brain were found to be immaturely
developed. The glial portion of the central and peripheral nervous system contains
cells that seem to be related to metabolism and metabolic functions supporting
the neurons and the nervous system blood vessels. When these cells are adversely
affected by alcohol there are often widespread effects throughout the nervous
system.
Magnetic
resonance imaging (MRI) studies of brain development in children with FAS have
shown reduced brain volume, especially in the cerebellum, basal ganglia, and
diencephalon, as well as a small or absent corpus callosum. Cerebellar functions
include posture, balance, motor coordination, and some integration of cognition.
The basal ganglia are involved in memory. The diencephalon is a key message
center of the brain, and the corpus callosum is the nerve center transferring
signals from one side of the brain to the other. Electroencephalograms (EEGs)
reveal more brain electrical activity than expected during both REM sleep and
quiet sleep, potentially leading to poor motor and cognitive development. These
defects reflect structural changes, but there are associated functional changes
as well. In fact, positron emission tomography (PET scan) reveals more functional
changes in brain activity than the structural changes would suggest.
The
most common neurobehavioral manifestations vary in their intensity. They may
be as subtle as fine tremors or as severe as seizures. In general, the neonate
will present with poor or weak sucking, irritability or hypersensitivity to
stimuli, exaggerated movements, and uncoordinated responses to caregiving attempts.
In the older infant and child, there may be hyperactivity, fine or gross motor
problems including incoordination, attention deficits, learning disabilities,
delayed language development, poor memory and judgment, impulsivity, and other
cognitive impairments. Mental retardation is strongly associated with FAS/FAE.
The more severe the physical manifestations, the more likely the IQ will be
severely impacted. Children who exhibit primarily cognitive symptoms may not
be diagnosed until they reach school age. Their facial features and overall
growth pattern may be close to normal. If the symptoms affect academic performance,
the school system may be the entity that determines there is a problem. Unfortunately,
teachers and school administrators often do not know much about Fetal Alcohol
Syndrome (FAS) or Fetal Alcohol Effects (FAE), and may not feel comfortable
in addressing their suspicions with the family.
•
Primary and Secondary Disabilities •
Research
differentiates between those disabilities that the child is born with,
termed primary disabilities, and those that are acquired over time,
termed secondary disabilities. Primary cognitive disabilities may
manifest themselves as deficits in general intelligence level; in ability
to master a specific academic skill such as reading, spelling, or arithmetic;
or in adaptive functioning. Thus the child with FAS may have a reading
and spelling level closely associated with their IQ level, but their math
ability, language development, and daily living skills as well as their
adaptive behavioral skills may be well below the expected level.
Secondary
disabilities result from a lack of attention to the primary disabilities, a
delay in diagnosis, or a lack of parental or other early intervention. The secondary
disabilities then, can include mental health problems, inappropriate sexual
behavior, disrupted school experience, legal difficulties, and alcohol or other
substance abuse problems. Studies suggest that secondary disabilities arise
from the ongoing interplay among the primary disabilities and the individual's
environment and life experiences. It is presumed that with some intervention
the secondary disabilities could be ameliorated. Whether the manifestations
are primary or secondary, a thorough assessment must be made.
Their
behaviors may bring children with FAS/FAE to the attention of school or legal
authorities first, and then later if at all to the health care community. Some
of these children will have never been diagnosed with FAS or FAE until then.
Even if they have had characteristic physical features early in their childhood,
the blending of facial features that occurs as the face elongates with increasing
age may make the dysmorphologies less noticeable. The microcephaly may also
become less prominent as the child's overall weight increases, especially at
puberty. The shortened stature, however, remains throughout life.
Assessment
Factors
•
How To Assess An Alcohol Exposed Fetus/Neonate •
The
neonate suspected of in utero alcohol exposure should be assessed for the hallmark
or classic triad of symptoms: intrauterine growth retardation (IUGR), craniofacial
anomalies, and central nervous system problems. The neonate should be observed
for poor sucking, uncoordinated movements, tremors, seizures, disturbed sleep/wake
patterns, hypersensitivity to stimuli, and inability to habituate to environmental
stimuli. The nurse in the delivery room at the time of the birth should attempt
to smell the amniotic fluid. If the amniotic fluid smells like alcohol, this
would be a red flag indicating exposure. Compare the head circumference, length,
and weight to determine if this infant is small for gestational age (SGA) and
has microcephaly. Assess for heart murmur that is often associated with ventricular
septal defects (VSD). This murmur, if present, will have to be followed, as
some perfectly healthy infants have murmurs due to patent ductus arteriosus
for the first few days of life. The FAS-related murmur will, however, persist.
Observe the intake and output of the infant, as some will have hydronephrosis
or urinary obstruction and therefore a diminished urinary output. A neonate
should have approximately 1 cc/kg/hour urinary output. Because many of the manifestations
are subtle and do not appear in every alcohol-exposed neonate, the diagnosis
is often delayed until preschool or school age.
•
Maternal History •
One
of the old diagnostic criteria for FAS was a positive maternal drinking history;
however, this is not generally required now. Some of these children may be placed
in foster or adoptive family care, so the mother's drinking history is not always
known. Sometimes, the birth mother may have died before the child comes to the
health professional's attention, thus making a positive maternal drinking history
impossible to obtain. However, if the mother's history can be obtained, determine
if there is documented alcohol or other substance use, including smoking during
the pregnancy. Elicit parity including any abortions or stillbirths. Determine
if there is any history of alcoholism in the family. If the mother has a history
of sexually transmitted diseases (STDs), is HIV positive, has hepatitis, or
exhibits signs of generally deteriorating health, there is a possibility that
she may have been using alcohol and other substances during her pregnancy.
Interventions
•
Primary Prevention •
Primary
prevention refers to the elimination of causes for a particular health problem
and focuses on reducing the occurrence of that problem. In the case of FAS,
the goal is to have no babies exposed to alcohol in utero. Therefore, abstinence
during pregnancy is the only way to guarantee the primary prevention of all
FAS and FAE in children.
In
considering primary prevention strategies, fathers become an integral part of
the process when dealing with FAS. The father of the baby must be encouraged
to adopt a non-drinking attitude also, in order to provide strong social support
and give additional meaning to the importance of not drinking during this time
period. Extended family members and peers can play an important role as well.
Education
is the key to primary prevention. Electronic and printed information can support
and reinforce positive action through knowledge about the adverse effects of
alcohol on the unborn baby.
•
Secondary Prevention •
Early
detection and prompt, effective interventions are measures associated with secondary
prevention. These are measures aimed at reducing the effects/severity of a particular
condition. In children with FAS, identification is a critical component that
is necessary in offsetting the severity of developmental effects associated
with in utero alcohol exposure. The sooner the neonate or child is recognized
as fetal alcohol exposed, the earlier inventions can be implemented to impede
secondary disabilities from occurring.
•
Developmentally Supportive Environment •
Developmental
care and a developmentally supportive environment are buzzwords in the area
of neonatal care. While most neonates with FAS/FAE are full term, some are exposed
to other substances or have other health-related problems that will cause them
to require a Neonatal Intensive Care Unit (NICU) stay. Developmental care refers
to sensitivity to infant cues of stability or stress, with appropriate interventions
to promote positive neurobehavioral development.
Stability
signals include such manifestations as even respirations, stable color,
smooth movements, hand to mouth movements, flexed posture, good muscle
tone, and organized sleep/wake patterns. The stress cues generally
include gaze aversion, yawning, disorganized sleep/wake patterns, tremors
or seizures, vomiting, irritability, labile shifts in responsiveness,
irregular breathing patterns, poor color, poor muscle tone, and poor posture.
A
developmentally supportive environment attempts to provide care that promotes
stability and discourages stress for the neonate and the family unit. It allows
the infant to dictate the timing of most care and requires the caregiver to
focus on clustering care activities to support long periods of undisturbed sleep.
Developmentally supportive care is cue-based and not task-oriented. Developmental
principles are integrated into caring for the infant and not performed as a
separate part of the nursing care. Specific interventions that may help support
the irritable infant include positioning techniques and providing boundaries.
Containment or nesting devices such as towel rolls placed behind the infant's
back or at the infant's feet provide boundaries for support and security. Swaddling
with blankets and bringing extremities to midline to move the infant into an
approximation of the fetal position has a calming effect.
An
infant that has been exposed to cocaine as well as alcohol may require vertical
rocking and a turning away from the human face in order to be consoled or quieted.
The rationale for these interventions is that vertical rocking takes into consideration
the alcohol-related changes in brain wiring, especially in the cerebellum and
glial or neuroglial areas. The human face is very stimulating, and often the
infant cannot take too much stimulation at one time.
Another
important aspect of this care is teaching the family or caregivers of
the infant to recognize stability and stress cues, so that these interventions
can be continued at home. This teaching can be viewed as positive for
the family if the emphasis is placed on what they can do for their
infant. Pointing out how they can keep the infant happy and safe may help
the mother feel better about herself and her caregiving abilities. She
needs to see that she has something that will work to soothe an otherwise
"cranky" infant. If she does not view the infant or her ability
to parent the infant as positive, then there is a greater risk for child
abuse and neglect. The parents need to be observed while they attempt
the developmental care interventions. This will provide cues to the nurse
as to how positively they interact with the child.
Remember,
too, that the father may also have an addiction and be adding to the mother's
dilemma of possibly feeling guilty about the infant's outcome. He may
pressure her to continue to drink or may blame her for the infant's illness,
leading her to increase her drinking in order to cope. Again, positive
coping skills sometimes can be increased with thorough teaching about
infant care needs and infant cues. Developmental care provides a good
vehicle for this type of teaching.
When
developmental care is implemented for an alcohol exposed infant, the results
are usually quite positive. Early intervention and the provision of developmental
care will promote positive neurobehavioral development and decrease the incidence
of secondary disabilities.
•
Early Intervention •
Early
intervention refers to strategies or services that are available to children
and families at risk for developmental disorders. These interventions can prevent
or ameliorate secondary disabilities for the neonate/infant with possible FAS
or FAE. The federal Individuals with Disabilities Education Act (IDEA) mandates
such programs, but FAS is only covered under IDEA if there are documented developmental
delays or disabilities. Thus it is imperative that developmental specialists
refer neonates who might be alcohol-exposed in utero for a comprehensive diagnostic
evaluation.
Once
the diagnosis of FAS/FAE is made, early intervention can begin. The focus of
early intervention is to support positive neurobehavioral development. The interventions
may be as simple as teaching parents how to stimulate their child without overstimulation,
how to repeat activities so learning occurs, and how to read their infant's
signals. The exact interventions are designed to meet the individual child's
needs and when possible are developmentally based according to the child's chronological
age.
Examples
of interventions based on chronological age include helping the infant during
feeding to make up for a weak suck, or swaddling the infant during feeding so
that the infant will feel more secure and be able to attend to the feeding.
If the mother is still drinking and is attempting to breast feed, she is taught
that alcohol crosses into the breast milk and that it is not good for the baby.
Not only do parents receive education on infant development so that they can
positively influence their child's growth, but they are supported in their own
growth during the process as well.
Children
with FAS or FAE who have gone through early intervention programs have shown
positive neurobehavioral growth, fewer attention problems, less severe learning
problems, and better language development than their counterparts who did not
receive such support. By working with the infant and family in a holistic way,
it is possible to decrease the long-term consequences of fetal alcohol exposure.
In
some areas of the country, programs that focus on early intervention strategies
for alcohol exposed children are referred to as "Zero to Three" programs,
because they include children in this age range and their families. In other
parts of the country, these programs are referred to as "Every Child Succeeds."
Healthy Families of America is another good resource for meeting early intervention
needs. Sometimes the pregnant alcoholic woman may have been enrolled in a Resource
Moms Program or a Healthy Families neighborhood program that uses nurses and
non-professionally trained personnel who make home visits to at-risk pregnant
women. The child and family enrolled in these programs are followed after birth
up to three years, again with the idea that early intervention for the child
and the family will help reduce the adverse effects of prenatal alcohol use.
For the woman who is pregnant and being seen in a local clinic with no home
visitation program, such community resources (if available) are important adjuncts
to traditional prenatal care. The March of Dimes Birth Defects Foundation in
White Plains, New York has a list of local March of Dimes agencies as well as
educational materials that cover alcohol and drug use during pregnancy.
Long-Term
Consequences of Fetal Alcohol Exposure
•
Infancy •
During
infancy, the primary manifestations of FAS/FAE are the same as those found
in the neonate. Affected infants are small in length and head circumference,
and their weight may be under the 50th percentile on growth charts. Many
exhibit disrupted sleep patterns. They continue to have feeding difficulties
due to a weak suck, and may exhibit failure to thrive. There are two types
of failure to thrive: organic and inorganic. Organic failure to
thrive has a definite systemic cause, due to their hyperirritability and
weak suck. Inorganic failure to thrive comes from psychosocial
rather than physiological causes and is commonly due to a dysfunctional
home and family environment.
•
Preschool Age •
Preschoolers
who are alcohol exposed in utero may exhibit language delays, hyperirritability,
temper tantrums and labile temperaments. They have difficulty adapting to change.
They cannot follow directions easily and therefore are often disobedient. They
may be difficult to toilet train and may have delays in walking.
They
are short in stature and often continue to be underweight.
|
National Center
of Continuing Education
