8: 6-day-old female with jaundice Flashcards
1
Q
Newborn Bilirubin Physiology
A
most (~75%) of the bilirubin produced in the healthy newborn comes from physiological breakdown of red blood cells.
2
Q
At high levels, unconjugated bilirubin unbound to albumin
A
can cross the blood-brain barrier and cause neurologic toxicity.
3
Q
Acute bilirubin encephalopathy occurs in the first few weeks of life.
A
- -Initial signs include poor suck, high-pitched cry, hypotonia, lethargy, seizures
- -Later signs include extensor hypertonia, opisthotonus (abnormal posturing that involves rigidity and severe arching of the back, with the head thrown backward)
4
Q
Kernicterus
A
- -pathological term used to describe staining of the basal ganglia and cranial nerve nuclei by bilirubin.
- -also describes the chronic clinical condition that results from the toxic effects of high levels of unconjugated bilirubin.
5
Q
Kernicterus results in abnormalities in
A
tone and reflexes, choreoathetosis, tremor, oculomotor paralysis, sensorineural hearing loss and cognitive impairment.
6
Q
In the setting of a significantly elevated serum bilirubin (e.g > 20-25 mg/dL), the following are risk factors for toxicity:
A
- Hemolysis (e.g. isoimmune hemolytic disease, G6PD deficiency)
- Asphyxia
- Significant lethargy
- Temperature instability
- Sepsis
- Acidosis
- Albumin < 3.0 g/dL
7
Q
Physiologic Jaundice definition
A
- total bilirubin level ≤ 15 mg/dL (≤ 257 μmol/L) in full-term infants who are otherwise healthy and have no other demonstrable cause for elevated bilirubin.
- Almost all newborn infants have hyperbilirubinemia, but it is benign and self-limited.
8
Q
Numerous factors promote the increased enterohepatic circulation that results in physiologic jaundice:
A
- Increased bilirubin production (from the breakdown of the short-lived fetal red cells)
- Relative deficiency of hepatocyte proteins and UDPGT
- Lack of intestinal flora to metabolize bile
- High levels of β-glucuronidase in meconium
- Minimal oral (enteral) intake in the first 2-4 days of life, resulting in slow excretion of meconium (especially common with breastfed infants).
9
Q
Jaundice Associated with Breastfeeding 1/2
A
- Happens early in the first week of life and occurs when the milk supply is relatively or absolutely low, resulting in limited enteral intake.
- this may be referred to as a “lack-of-breast milk jaundice” or “breastfeeding-associated jaundice.”
- The low intake results in decreased gastrointestinal motility that in turn promotes retention of meconium.
- The β-glucuronidase in meconium deconjugates bilirubin and the unconjugated bilirubin is reabsorbed via the enterohepatic circulation, causing an elevation of serum levels.
- Occasionally, persistently low vol of breast milk can cause the neonate to become dehydrated and malnourished. difficult to distinguish f/m physiologic jaundice.
10
Q
Jaundice Associated with Breastfeeding 2/2
A
- Begins in the first 4 to 7 days of life but may not peak until about 10 to 14 days.
- Not the result of low breast milk volume.
- While the cause is not completely understood, one explanation is that β-glucuronidase present in breast milk deconjugates bilirubin in the intestinal tract; the unconjugated bilirubin is then reabsorbed via enterohepatic circulation.
- Breast milk jaundice can persist for up to 12 weeks, but total bilirubin concentration rarely, if ever, reaches concerning levels.
11
Q
Etiologies of early newborn jaundice: Hemolysis
A
- Ab-positive hemolysis is labeled “direct Coombs” or “direct antibody test (DAT)” positive. The m/c forms of ab-positive hemolysis include:
- -Rh incompatibility (mother is Rh-negative and baby is Rh-positive)
- -ABO incompatibility (mother is type O and baby is type A or B)
- -Incompatibilities with minor blood group antigens (much less common)
- Ab-negative hemolysis occurs in infants who have rbc membrane defects (e.g., spherocytosis) or rbc enzyme defects (G6PD or pyruvate kinase deficiency).
12
Q
Etiologies of early newborn jaundice: Non- hemolytic red cell breakdown
A
- Inc bilirubin production and development of jaundice and occurs in a variety of conditions, inc:
- –Extensive bruising from birth trauma
- –Large cephalohematoma or other hemorrhage (e.g., intracranial)
- –Polycythemia
- –Swallowed blood (large amounts) during delivery
13
Q
Etiologies of early newborn jaundice: Other Causes aka Metabolic errors
A
- Crigler-Najjar syndrome type 1 and type 2
- Gilbert Syndrome is a much less severe but more common cause of unconjugated hyperbilirubinemia than Crigler-Najjaar.
- Galactosemia and hypothyroidism
14
Q
Etiologies of early newborn jaundice: Neonatal sepsis
A
While sepsis can lead to jaundice, jaundice as the only sign of sepsis is rare.
15
Q
Etiologies of early newborn jaundice: Congenital Infection
A
- In utero exposure to one of the TORCH infections can lead to jaundice.
- Physical findings may include hepatosplenomegaly, microcephaly, and/or rash.
16
Q
successfully breastfed baby
A
- -typically nurses 8-12 times in 24 hours.
- -Feedings may initially last up to 60 minutes but gradually become shorter in duration, ~10-15 minutes at each breast. (Increasingly frequent or consistently lengthy feeding sessions may indicate a problem, especially if the infant is not gaining weight.)
17
Q
Benefits of breastfeeding for infants
A
- Maternal-infant bonding
- Protection against some infections (e.g. otitis media, respiratory infections, diarrhea)
- Reduced rates of Sudden Infant Death Syndrome
- Reduced rates of some allergic reactions
18
Q
Benefits of breastfeeding for mothers
A
- Dec postpartum bleeding and more rapid uterine involution
- Lactational amenorrhea and delayed resumption of ovulation with increased child spacing
- Earlier return to pre-pregnant weight (compared with women who formula-feed)
- Improved bone remineralization postpartum with reduction in hip fractures in the postmenopausal period
- Decreased cost, relative to formula
- Ready availability without preparation time
19
Q
Carbohydrates
A
- Both human milk and standard infant formulas contain lactose as the major carbohydrate.
- Lactose intolerance is uncommon in the first year of life.
20
Q
Lipids
A
- Approximately 50% of calories in human milk come from lipids.
- The lipid concentration in breast milk inc as the nursing episode proceeds; therefore, its important that an infant empty the breast before going to the next breast.
21
Q
Proteins
A
- Human milk contains a combo of whey proteins (70%) and casein (30%).
- Formulas provide nutrition comparable for all major nutrients to human milk, although they contain slightly more protein than human milk.
- The casein:whey ratio of cow-milk-based formulas varies.
- Unmodified cow milk contains approx 3x the protein content of human milk and has ~80% casein and 20% whey proteins.
22
Q
Common breastfeeding problems
A
- Enlarged, tender breasts-commonly caused by engorgement, mastitis, or plugged ducts (galactocele)
- Improper latch, suckle
- Prolonged feedings
- Infants fall asleep before they finish feeding
- Maternal inexperience/anxiety
23
Q
Hemolysis leading to elevated circulating bilirubin and possible jaundice can be caused by a variety of disorders in the red blood cell, including:
A
- Intrinsic cell membrane defects (such as spherocytosis and elliptocytosis)
- Enzyme disorders (such as G6PD deficiency <> and pyruvate kinase deficiency) -Hemoglobinopathies (such as the thalassemias and sickle cell anemia)
24
Q
Biliary Atresia
A
- -A healthy-appearing infant who develops jaundice, dark urine, and acholic (pale) stools between 3 and 6 weeks of age may have biliary atresia.
- -Any infant who develops jaundice after 2wk must be evaluated with fractionated bilirubin (i.e., total and direct bilirubin levels).
- -A pt suspected of having biliary atresia generally will be referred to a peds gi or pediatric surg.
25
Biliary atresia treatment
- When diagnosed early, biliary atresia can be treated surgically with the Kasai procedure (anastomosis of the intrahepatic bile ducts to a loop of intestine to allow bile to drain directly into the intestine).
- If done early, the Kasai procedure will restore bile flow and prevent liver damage.
26
Voiding in the NBN
- Urination changes in the first days after birth:
- Day 3: The baby should be voiding 3-4 times a day.
- Day 6: Baby should be voiding at least 6-8 times a day.
- Urine should be pale yellow.
27
Stooling in the NBN
- Day 3: Meconium should no longer appear in the stool and bowel movements should begin to appear yellow.
- Day 6 or 7: Most newborns have 3-4 stools per day, although many infants pass stool with every feeding.
- Stool passed by breastfed infants has little odor. You should be concerned if an infant's stool gradually loses color and becomes "acholic" (without bile), as this may be a sign of biliary atresia.
28
Risk factors for severe hyperbilirubinemia (TSB > 95th percentile) (1/3)
Major Risk Factors:
- Pre-discharge total serum bilirubin (TSB) or transcutaneous bilirubin (TcB) level in the high-risk zone
- Jaundice observed in the first 24 hours of life
- Blood group incompatibility, with positive direct antiglobulin test
- Gestational age 35-36 week
- Previous sibling received phototherapy
- Cephalohematoma or significant bruising
- Exclusive breastfeeding, particularly if nursing is not going well and weight loss is excessive
- East Asian
29
Risk factors for severe hyperbilirubinemia (TSB > 95th percentile) (2/3)
Minor Risk Factors
- Pre-discharge TSB or TcB level in the high intermediate-risk zone
- Gestational age 37-38 week
- Jaundice observed before discharge
- Previous sibling with jaundice
- Macrosomic infant of a diabetic mother
- Maternal age >25 y
- Male gender
30
Risk factors for severe hyperbilirubinemia (TSB > 95th percentile) (3/3)
Decreased Risk
- TSB or TcB level in the low-risk zone
- Gestational age 41 week
- Exclusive formula eeding
- Black (lol)
- Discharge from hospital after 72 hours
31
cephalohematoma
- subperiosteal hemorrhage that is localized to the cranial bone that was traumatized during delivery.
- The swelling does not extend across a suture line.
- As the blood is reabsorbed from the cephalohematoma it will contribute to hyperbilirubinemia.
32
Bruising
on the head or elsewhere on the body from birth trauma or any other bleeding can also lead to increased bilirubin production because blood extravasated into tissues will be broken down and converted to bilirubin.
33
caput succedaneum
edematous swelling over the presenting portion of the scalp of an infant and is commonly seen in babies born vaginally in vertex position. Because the scalp overlies the periosteum, this boggy swelling crosses suture lines, easily differentiating it from a cephalohematoma.
34
Newborn physical findings: Anterior fontanelle
On the initial newborn examination, shortly after birth, the anterior fontanelle may barely be open because of overriding sutures. Within a few days as the sutures open up, the anterior fontanelle becomes more easily palpable. The average diameter of the anterior fontanelle is in the range of 2.5-5 cm.
35
Newborn physical findings: Posterior fontanelle
-In most full term newborns the posterior fontanelle is not palpable at birth or later.
Infants with significant hemolytic disease and jaundice in the first 24h may also have hepatosplenomegaly and pallor.
-Infants whose jaundice is caused by congenital infections such as CMV, toxo, syphilis, rubella, or herpes may have hepatosplenomegaly along w/ elevated direct and indirect bilirubin levels.
36
Weight Gain in Newborns
Breastfed infants may lose up to 7%-10% of their birth weight during the first 4 to 5 days of life, and typically regain birth weight by at least 2 weeks of age.
37
Tylenol #3
(a combination of acetaminophen and codeine, a narcotic analgesic) would not be recommended as a first choice. Codeine, which metabolizes to morphine, is passed into breast milk. Although the amt is probably insignificant, some women who are rapid metabolizers of codeine may excrete high levels of morphine in breast milk.
38
Supplementation: Vitamin D
To avoid the development of rickets, exclusively breastfed infants need vitamin D supplementation in the first 6 months of life.
39
Supplementation: Iron
- Most pediatricians do recommend the addition of iron-containing foods to the infant's diet, starting at age 6 months.
- Most standard formulas are iron-fortified.
40
Supplementation: Fluoride
- Breast- and bottle-fed infants both should receive fluoride supplements after the age of 6 months if the water supply lacks fluoride (< 0.3 ppm).
- most bottled and filtered water has low fluoride levels.
41
When jaundice persists, however, it is important to
- check for either dark urine or acholic-appearing stools that might signify the development of cholestasis.
- It is also reasonable to obtain total and direct bilirubin levels (also known as "fractionated bilirubin") to be sure that the direct bilirubin is not beginning to climb.
42
biliary atresia
can present anytime between birth and 8 weeks of age, but usually occurs after 2 weeks of age. Jaundice is usually the first presenting finding, along with acholic stools, dark urine (from increased bilirubin excretion) and hepatosplenomegaly if the problem goes unrecognized. Laboratory values classically show an increased level of direct or conjugated bilirubin > 2 mg/dL. If biliary atresia is confirmed with further laboratory testing and imaging, surgical intervention must be pursued as soon as possible.
