to carry oxygenated blood from the placenta to the fetus
What is the role of the ductus venosusin the fetal cardiovascular system?
allows for the majority of the umbilical vein blood to bypass the liver and merge with blood moving throught vena cava, bringing it to the heart sooner
What is the purpose of the foramen ovale in the fetal heart?
to allow more than half the blood entering the right atrium to cross imediately to the left atrium, thereby passing the pulmonary circulation.
The physical forces of the contractions of labor and birth, mild asphyxia, increased intracranial pressure as a result of cord compression and uterine contractions, as well as cold stress immediately experienced after birth lead to an increased release in __________________ that is critical for the changes involved in the transition to extrauterine life.
the increased levels of _________ and __________stimulate increased cardiac output and contractility, surfactant release, and promotion of pulmonary fluid clearance
epinephrine and norepinephrine
Describe fetal respiratory system.
fluid filled, high pressure system causes blood to be shunted from the lungs through the ductus arteriosus to the rest of the body.
Describe the newborn respiratory system.
air filled, low pressure system encourages blood flow through the lungs for gas exchange; increased oxygen content of blood in the lungs contributes to the closing of the ductus arteriosus (becomes a ligament).
Where is the site of gas exchange in the fetus?
Where is the site of gas exchage in the newborn?
Describe circulation through the heart of a fetus?
Pressures in the right atrium are greater than in the left, encouraging blood flow through the foreman ovale.
Describe circulation through the heart of a newborn.
Pressures in the left atrium are greater than in the right, causing the foreman ovale to close.
Describe hepatic portal circulation in the newborn.
Ductus venosus closes (becomes a ligament); hepatic portal circulation begins.
How is thermoregulation maintain in the fetus?
body temperature is maintained by maternal body temp and the warmth of the intrauterine environment.
How is thermoregulation maintained in the newborn?
Body temp is maintained through a flexed posture and brown fat.
What is the normal HR in a newborn?
in the first few minutes of life it is 120-180 bpm and then begins to decrease to an average of 120-130 bpm
Transient functional cardiac murmurs may be heard during the neonatal period as a result of the changing dynamics of the cardiovascular system at birth.
Tachycardia may be found with volume depletion, cardiorespiratory disease, drug withdrawal, and hyperthyroidism.
Bradycardia is often associated with apnea and is often seen with hypoxia.
What is the estimated blood volume of a term infant?
80-85 mL/kg of body weight.
could vary as much as 25-40 % depending on when the umbilical cord was clamped.
What is considered to be early umbilical clamping?
before 30 to 40 seconds of birth
What is considered to be late umbilical clamping?
after 3 minutes
What is the life span of the newborn's red blood cells?
adult- 120 days
What happens to the hemoglobin initially as a result of a decrease in neonatal red cell mass?
levels decline (called physiologic anemia of infancy)
What blood cells are elevated as a result of birth trauma soon after birth?
leukocytes (white blood cells)
The newborn's platelet count and aggregation ability are higher/lower/same when compared to adults?
When drawing blood from a newborn, which site has higher levels of hemoglobin and hematocrit?
capillary blood as opposed to venous blood
What is tidal volume?
amount of air brought into the lungs
What is surfactant and what is its purpose?
a surface tension-reducing lipoprotein found in the newborn;s lungs that prevents alveolar collapse at the end of exiration and loss of lung volume.
What it the normal hemoglobin range in a newborn?
What is the normal Hematocrit range in a newborn?
What is the normal Platelets range for a newborn?
What is the normal red blood cell range in a newborn?
What is the normal white blood cell range in a newborn?
All of the following must occur for the newborn's lungs to maintain repiratory function.
intiation of respiratory movement
expansion of the lungs
establishment of functional residual capacity (ability to retain some air in the lungs on expiration)
increased pulmonary blood flow
redistribution of cardiac output
Describe normal respirations pattern and rate of a newborn.
shallow and irregular
ranging from 30 to 60 bpm with short periods of apnea (less than 15 seconds)
What is periodic breathing?
cessation of breathing that lasts 5 to 10 seconds without changes in color or heart rate.
requires close monitoring
What is the normal newborn's temp range/
36.5-37.5 C (97.9 to 99.7 F)
What is thermoregulation?
process of maintaining the balance between heat loss and heat production.
The newborn temp can decrease 3 to 5 degrees within minutes after leaving the warmth of the mother's uterus.
What is conduction?
transfer of heat from one object to another when the two objects are in direct contact with each other.
What is convection?
flow of heat from the body surface to cooler surrounding air or to air circulation over a body surface.
What is radiation?
loss of body heat to cooler, solid surfaces in close proximity but not in direct contact with the newborn.
The primary heat regulator is located where in the body?
hypothalamus and the central nervous system
Ways the newborn attemps to conserve heat and increase heat production.
increasing the metabolic rate
increasing muscular activity through movement
increasing peripheral vasoconstriction
assuming a fetal position to hold in geat and minimize exposed body surface
What is a neutral thermal environment (NTE)?
an environment in which body temp is maintained without an increase in metabolic rate or oxygen use
How the newborn respond to a decrease in environmental temperature?
consumes more oxygen
respiratory rate increases (tachypnea)
metabolic rate increases
What is the newborn's primary method of heat production?
brown fat (adipose tissue) is oxidized
brown fat- highly vascular fat only found in newborns; capable of intense metabolic activity
found between scapulae, at the nape of neck, in the mediastinum, and areas surrounding the kidneys and adrenal glands
makes up 2-6% of body weight
cold triggers increase in norepinephrine which stimulate brown fat metabolism by the breakdown of triglycerides
cardiac output increases blood flow through brown fat and warms blood as a result
What is cold stress?
excessive heat loss that requires a newborn to use compensatory mechanism (such as nonshivering thermogenesis and tachypnea) to maintain core body temp.
As the body temp decreases the newborn becomes less active, lethargic, hypotonic, and weaker.
Cold stress can lead to the following if not reversed.
depleted brown fat stores
increased oxygen needs
increased glucose consumption leading to hyoglycemia
decreased surfactant production
Avoid placement of skin temp probe over a bony area or one with brown fat, because it does not give an accurate assessment of the whole body temperature (most probes are placed over the liver when the newborn is supine or side lying).
The hepatic system function of a newborn include:
conjugation of bilirubin
At birth the newborn has iron stores sufficient to last approximately how long?
A newborn's blood glucose level is what % of mother's?
What is the main source of energy for a newborn the first several hours after birth?
Where does the newborn get it's glucose in the first 24 hours of life.
the liver releases glucose from glycogen stores
How and when are blood glucose levels assessed on a newborn?
upon admission to nursery and at 4 hours old using a heel stick sample
Because newborns produce bilirubin at a rate of 6-8 mg/kg/day (more than twice the production rate in adults) resulting from polycythemia and increased red blood cell turnover, it is common for them to develop what problem since the liver is immature and cannot conjugate bilirubin as quickly as needed?
Extemely elevated levels of bilirubin during the first week of life can cause __________.
kernicterus-permanent and devastating form of brain damage
Common risk factors for jaundice:
fetal-maternal blood group incompatibility
drugs- valium, pitocin, pediazole, chloromycetin
maternal gestational diabetes
trauma during birth resulting in cephalhematoma
previous sibling with hyperbilirubinemia
infection such as TORCH (toxoplasmosis, other viruses, rubella, cytomegalovirus, herpes simplex viruses)
ethnicity such as Asian or Native American
What is required for the production of vitamin K in the newborn?
colonization of the gut- should happen within 24 hours
dependent on oral intake
The capicity of the newborn's stomach is __________?
30 to 90 mL with an emptying time of about 2 to 4 hours
Why do newborn's have a limited ability to digest complex carbohydrates?
amylase and lipase levels are low at birth
How many kcals does the newborn require to gain weight from to 6 months?
What is meconium?
composed of amniotic fluid, shed mucosal cells, intestinal secretions, and blood usually passed within 12 to 24 hours of birth.
At what age does the newborn's kidneys begin to concetrate urine?
Until the kidneys are able to concentrate urine (at about 3 months of age) what is the expected specific gravity of newborn's urine.
1.001 to 1.020
What is an idication of adequate fluid intake in a newborn?
six to eight voidings daily
At what age does the renal cortex reach maturity?
12-18 months of age
Immunoglobulins are subdivided into five classes:
What are the main three immunoglobulins for defense mechanism in newborns?
makes up about 80% of all circulating antibodies
found in serum and interstitial fluid
only class able to cross placenta
produces antibodies against bacteria, bacterial toxins, and viral agents
second most abundant
does not cross placenta
maximum levels reached during childhood
protects mucous membranes from viruses and bacteria
predominantly found in gastrointestinal and respiratory tracts, tears, saliva, colostrum, and breast milk (major source)
found in blood and lymph fluid
first to respond to infection
does not cross placenta
levels are generally low at birth unless there is a congenital intrauterine infection
major source of protection from blood borne infection
predominant antibodies formed during neonatal or intrauterine infection
The first period of reactivity
begins at birth and last for 30 min
alert and moving and may appear hungry
myoclonic movements of eyes
spontaneous moro reflexes
fine tremors of extemities
respiration and HR elevated but gradually begin to slow
Period of deceased responsiveness
at 30 to 120 min of age
second stage of transition
sleep or decrease in activity
movements less jerky and less frequent
HR and RR decline as enter sleep phase
deminished response to outside stimuli
difficult to arouse or interact with
no interest in sucking
Second period of reactivity
begins as newborn awakens and shows interest in environmental stimuli
lasts 2 to 8 hours in normal babies
HR & RR increase
common to pass meconium during this period
motor activity and muscle tone increase in conjuction with an increase in muscular coordination
What is neurobehavioral respone?
how the newborn reacts to the world around them
The response of newbons to stimuli is called _______________.
What is habituation?
the newborn's abilty to process and respond to visual and auditory stimuli and become accustomed to activity
What are the names of the three shunts in the newborns heart that close and become ligaments over time?
Describe APGAR scores in terms of severe, moderate, and no distress.
0-3 severe distress
4-6 moderate distress
7-10 no distress
A gestational age assessment is performed how soon after birth?
within 2-12 hours of birth
What is the name of the scale used to determine gestational age?
New Ballard Scale
Normal ranges of physical measurements of newborns.( pg. 298 ATI)
Weight - 2,500-4,000 grams
Length - 45-55 cm (18-22 in)
Head Circumference - 32-36.8 cm (12.6-14.5 in)
Chest circumference - 30-33 cm (12-13in)
What weight is considered to be low birth weight?
2,500 g or less at birth
What is a (IUGR) intrauterine growth restriction?
growth rate does not meet expected norms
a baby born prior to the completion of 37 weeks of gestation is considered to be what?
preterm or premature
A baby born after the completion of 42 weeks of gestation is considered to be what?
A baby that is born after the completion of 42 weeks of gestation with signs of placental unsufficiency is termed?
List the sequence in which vital signs are performed.
When are short periods of apnea most likely to occur in newborns?
during the rapid eye movement sleep cycle
Crackles and wheezing are symptoms of what?
fluid or infection in the lungs
What is the normal blood pressure of a newborn?
60-80 mm Hg systolic
40-50 mm Hg diastolic
What happens if a baby becomes chilled (cold stress)?
oxygen demands can increase and acidosis can occur
What are small raised white spots on the nose, chin, and forehead called?
Milia- disappear spontaneously , should not be squeezed
Describe a mongolian spot.
bluish purple spots of pigmentation commonly noted on newborn's shoulder, back, and buttocks
frequently on dark skinned babies
What is the name for a flat pink or red mark that easily blanches and found on back of neck, nose, upper eyelids, and middle of forehead.
Telangiectatic nevi (stork bites)- usually fade by the second year of life
What is a Nevus flammeus (port wine stain)?
Capillary angioma below the surface of the skin that is purple or red, varies in size and shape, commonly seen on face and does not blanch or disappear.
What is a pink rash that appears suddenly anywhere on the body of a term newborn during the first 3 weeks called?
Erythema toxicum (erythema neonatorum)-- no treatment required
The head of a newborn should be how much larger than his chest circuference?
4 cm larger than chest indicates hydrocephalus
Head circ less than or equal to 32 cm indicates microcephaly
What is the approximate size and shape on the anterior fontanel?
5 cm with a diamond shape
What would a bulging fontanel indicate?
What would a depressed fontanel indicate?
What is caput succedaneum?
localized swelling of the soft tissues of the scalp caused by pressure on the head during labor
normal finding that may be palpated as a soft edematous mass and may cross over the suture line.
usually resolves in 3-4 days and does not require treatment
What is a cephalohematoma?
a collection of blood between the periosteum and the skull bone that it covers.
does not cross the suture line
results from trauma during birth such as pressure of the fetal head against the maternal pelvis in a prolonged difficult labor or forceps delivery.
appears in the first 1-2 days after birth and simultaneously resolves in 2-3 weeks
When is permanent eye color established in the newborn?
within 3 to 12 months
Ears that are set low can indicate what disorders?
Lack of ear cartilage indicates what?
What would be an indication of a tracheoesaphageal fistula in a newborn?
Describe epstein pearls?
small white cysts found on the gums and at the junction of the soft and hard palates
disappear a few weeks after birth
A protruding tongue may be a sign a which disorder?
What could absence of head control indicate in a newborn?
prematurity or down syndrome
How soon after birth should bowel sounds be present?
1 to 2 hours following birth
Urine should be passed within 24 hours after birth.
The rust color of urine is caused by what in the newborn?
Uric acid crystals
Reflexes that should be present until around 4 months of age:
Sucking and rooting
Moro reflex (startle)
Tonic Neck Reflex (fencer position) (3-4 Months)
Reflexes that should be present until around 6 months of age:
Reflexes that should be present until around 8 months of age:
Reflexes that should be present until around 1 year of age:
What is the normal hemoglobin value for a newborn?
14 to 24 g/dL
What is the normal hematocrit value for a newborn?