EXAM 1 (presentations) Flashcards
what is the normal hematocrit at birth?
43-65%
**hematocrit normally elevates in the first few hours/day and normally falls back to normal by 1 week d/t to fluid shift
what is Neonatal Polycythemia ?
hemotacrit >65%
Venous vs Capillary blood r/t to hematocrit
Capillary blood sample will have higher hematocrit
Venous sample is more accurate
what is partial exchange transfusion
treatment to remove polycythemia
–> by infusing saline or a blood product (albumin) to decrease the hematocrit
done through the umbilical artery
Fetal hemoglobin
15g/dL
higher than adult because they have higher affinity for oxygen
Neonate hemoglobin increases up to 6g/dL w/in a few hours after birth (fluid shift)
Hemoglobin peaks at 4-6 hours & decreases to cord blood value w/in 1 week
(left shift on oxygen-hemoglobin dissociation curve meaning that oxygen is more tightly bound to the hemoglobin)
neonatal hemoglobin
14-20g/dL
**newborns have both fetal hemoglobin and adult hemoglobin
**adult hemoglobin slowly takes over
so fetal hemoglobin breakdown faster causing physiological anemia at 6-8 weeks of age. average is 12.0g/dL in a 2 month old.
adult hemoglobin
12g/dL
signs and symptoms of polycythemia
hct >65% or hgb >22g/dL ruddy appearance plethora (high blood content) causes: chronic hypoxemia, maternal smoking altitudes, cyanotic heart disease, IUGR, maternal hypertensive disorders, DM mothers, trisomy 13, 18 & 21, Beckwith-Wiedemann syndrome or congenital adrenal-hyperplasia Uncommon if less than 34 weeks gestation
newborn urinary system
*** fetus–>empty/fill bladder every 20-30min
newborns are born with an adult number of nephrons, however immature.
newborn renin-angiotension system
increases !
as result the renal blood flow increases markedly w/in 24 hours of life
newborn kidneys still have limitations both in structure and function (shorter uterer)
when do newborns begin to regulate urine
at 3 months of age
newborns can only concentrate their urine to half of adult levels
glomerular filtration rate in newborns
doesn’t catch up with respect to body surface area until age 1
this mean in healthy full term newborns the kidney are immature
**at risk for overhydration/dehydration
**at risk for drug toxicity
what is normal –> teaching about urine system of newborn
there is urine in the bladder at birth
patient should expect the first void w/in 24 hours at birth (95%) but up til 48 hours !
urine should be pale straw colored
there are sometimes uric acid crystals present in the urine (1st day or two otherwise it is a sign of dehydration)
how much voids is normal
1 per day for the first 48 hours
6-10 voids per day in day #3-5 (breastfed/bottle fed)
water for baby
water supplements is extremely dangerous for infant d/t risk of water intoxication
GI system (fetal)
primarily to remove the amniotic fluid
at 38 week–> establish suck/swallow/breathing coordination
GI system (newborn)
supplying newborn’s energy nutritional and fluid needs.
intestinal motility tends to be disorganized and slower in NBs. this leads to increased transit time and delayed emptying, putting the NB at risk for regurgitation
NB’s colon does not conserve water as efficiently as adult colon and can lead to severe water loss.
intestinal surface of the newborn
immature intestinal surface leads to DECREASED absorptive surface
decrease turnover of intestinal epithelia cells leads to inadequate functional surface area. this affects digestion, absorption and host defense
- **feeding after birth stimulates the intestinal lining promoting rapid cell turnover and stimulating production of microvillanous enzymes such as amylase, trypsin, and pancreatic lipase
- **most NBs are able to digest and absorb proteins and carbohydrates but not as efficiently as adults **
Glucoamylase
is a brush border enzyme evenly distributed along the small intestine which helps the NB digest glucose polymers found in breast milk and formula
what is gut closure
the GI system serves as a continuation of human immune system
In NB the “gut closure” does not occur til 4-6 months of age. this means macromolecules and bacterial can penetrate the mucosal lining increasing risks for infection and allergies.
Newborn intestine
intestine are sterile at birth but rapidly colonize
intestinal bacteria are an important source of vit. K, but it take up to 6 weeks for NB to build an adequate supply
*in breastfed infants maternal secretory IgA working at local level restricts immune activation and bacterial attachment
why passage of meconium is important
because it is essential step in initiation of intestinal function. if meconium stays in the gut over a prolonged period there is an increased risk of hyperbilirubenemia !
GI colonization process
change in symbiotic relationship with beneficial organisms which promote immune homeostasis
**disrupt of immune homeostasis has been found to increase the incidence of asthma and other immune diseases later in life.
Oligosaccharides
found in breast milk, act as prebiotics which preferentially promote the proliferation of bifidobacteria and lactobacillus.
implications for practice regarding GI system of newborn
–> breastfeeding promotion and support during antenatal intrapartum and postpartum
–> Skin to skin with mom right after birth with breastfeeding w/in 1 hour of birth
if mom unable to breastfeed expressed milk can be used to feed the baby
Documentation of passage of meconium
monitor NB for excessive wt. loss
teaching to parents about GI system
start breastfeeding as soon as baby is born can help protect baby against common diseases
Colostrum is easily swallowed and digested by baby it also helps with intestines to begin maturing faster
colostrum help baby pass meconium
most baby pass meconium by 24-48 hours after birth
better to breastfeed exclusively
do not introduce regular food til baby is at least 6 months old
fetus circulatory system
- -> neonate child & adult require more oxygen than fetus
- ->fetus is able to compensate by increase its oxygen perfusion rate (higher than of an adult) to maximize oxygen delivery to vital organs
- ->fetal lungs are in a collapsed state and the pulmonary arteries are thickened, creating a state of high pulmonary vascular resistance (increase PVR)
- -> increase PVR minimizes blood flow to lungs and encourages the return of blood to the placenta for oxygenation
umbilical vein
bring OXYGENATED BLOOD from placenta into the fetus
ductus venosus
BYPASSED the liver and connects to the inferior vena cava (IVC)
the oxygenated blood mixes with deoxygenated blood in the (IVC) and is transported into the right atrium (RA ) of the heart.
foramen ovale
connect the RIGHT ATRIUM to the LEFT ATRIUM and moves majority of the blood from the right to left
from left atrium blood moves to left ventricle and is ejected into the ascending aorta to deliver well oxygenated blood to the head neck and upper limbs via the left carotid, coronary and subclavican arteries
ductus arteriosus
connect PULMONARY ARTERY to the DESCENDING AORTA and BYPASSes approximately 90% of blood past the lungs to return it to the placenta
umbilical arteries
SPIRAL around umbilical vein and return the blood from internal iliac arteries to the placenta for reoxygenation.
neonatal circulation
-first breath
-placenta is removed
- foramen ovale: close w/in few hours
-ductus arteriosis : 10-96 hours close , total closure 1-2 mos
-ductus venosus: few days to one week.
umbilical vein close w/in few days turn into ligament .
umbilical arteries : clot quickly turn to ligament
physiologic changes
lung start working to oxygentate the bldy
closure of ductus arteriosus forament ovale, and ductus venosus
umbilical arteries constricts after birth
umbilical vein remains patent for some time
vascular pressure changes after birth
systemic vascular resistance (SVR) INCREASE
pulmonary vascular resistance (PVR) DECREASE
blood flow in the LEFT side of the heart INCREASE
Cardiac exam reveals systolic murmur and high pitch heart tones
in healthy newborn, functional murmurs, clicks, hums, and high pitch sounds of greater intensity can be normal findings as the newborn functionally transitions to extrauterine life.
MURMUR self resolve ! Murmurs are heard in approximately 1/3 of healthy infant though the firs 24 hours of life and 2/3 thought he first 48 hours of life.
systolic murmurs are more audible approximately 15% of healthy newborns for 5-6 hours after birth as DUCTUS ARTERIOSUS begins to close
implications for practice
recognize normal vs abnormal :
not uncommon to see baby with blueish extremities d/t acyanosis –>oxygen more to brain
Mindful resuscitation
it is estimated that approx. 1 out of 10 healthy newborns will require assistance with their first breath
life-saving interventions should benefit mother-infant interaction and unnecessary procedures (eg. routine suctioning immediate separation from mothers) should be discontinued
early and prolonged skin to skin has been shown to promote cardiopulmonary stability as well as decrease the distress level of the infant
innate immunity
barriers
inflammation
adaptive immunity
cellular
antibody mediated (humoral)
–> active acquire
—>passive acquire
physical mechanical and chemical BARRIERS of innate immunity
epithelial cells of the skin & mucous membranes
coughing and sneezing
mechanical cleaning and sloughing of cells
ciliary action
biochemical secretions such as mucous, perspiration, saliva, tears, and earwax
presence of protective proteins call antimicrobial peptides
normal bacterial flora
INFLAMMATORY response
–> heat redness edema & pain
vasodilation following an injury increases blood flow and capillary permeability goal is to dilute toxin producing bacteria
the vascular changes allow for delivery of leukocytes, plasma proteins and other biochemical mediators to the site of injury
Acute phase of Inflammatory response
there are 3 plasma protein system which play roles in inflammatory response
(1) complement system
(2) clotting system
(3) kinin system
* ***they work in conjunction w/ one another with anitmicrobial peptides and the cellular level to prevent bacterial invasion
* **cells involve in the inflammatory process include mast cells, neutrophils, monocytes, macrocytes, eosinophils, NK cells, platelets and nonleukocytic cells.
Mast cells (role in inflammatory response)
central role to all types of physical injuries and allergies reactions
neutrophil (role in inflammatory response)
aka POLYMORPHONUCLEUS NEUTROPHILS (PNM) are arrive w/in 6-12 hours and ingest bacteria damaged cells and debris
monocytes (role in inflammatory response)
produced in bone marrow migrate to the site & then transform into macrophages. Macrophages assist with cleaning the area and healing promotion
macrophages stimulate the activation of the adaptive immune system
eosinophil (role in inflammatory response)
minimize the extent of the inflammatory response which reduces healthy tissue damage. they also fight against parasitic invasion
NK cells
specializes in the elimination of viruses, abnormal cells and cancer cells
platelets
promote bleeding cessation and aid in inflammatory control
Antigen Binding & Destruction
can occur with only 3 types of lymphocyte receptors complexes :
(1) antibodies
(2) B-lymphocytes (B-cell receptor )
(3) T-lymphocytes (T-cell receptor)