Case 7: Newborn - transient tachypnea of the newborn

Question 1

Mgmt:

1 hour old infant in nursery with grunting

Born at 35 0/7 weeks, SROM, vaginal delivery, clear fluid
Apgars 7 and 8
Prenatal labs “normal”, GBS unknown
Shortly after delivery noted to have increased respiratory effort
Now what?

Vital signs: T 37.4, HR 168, RR 72, BP 68/46, Sat 86% in RA
Gen: Small infant in mild distress
HEENT: NCAT, AFOF. + nasal flaring
CV: RRR, no murmur
Lungs: Coarse to auscultation bilaterally without focal findings. + intercostal and subcostal retractions
Abdomen: Soft, NTND, NABS, no HSM
Neuro: Alert, good tone, MAEW

Answer 1

Still have risks of prematurity (though lower than those born <34w)

1) Oxygen (NC, blow by, head box, mask)
2) continuous monitoring
3) Transfer to NICU
4) infection labs, CXR, pre and post-ductal sats

Diffdx

• infection
• RDS due to surfactant deficiency ==> preterm, more distress than TTN
• Transient Tachypnea of the Newborn ==> presents within 2 hours, lasts <72 hours, tachypnea most prominent (“happy tahypnea”). Usually 24-37 weeks
• Meconium aspiration
• Persistent pulmonary hypertension ==> Usually term, splitting of pre and post ductal sats, often with meconium aspiration; esp with tachypnea
• Congenital heart disease ==> usually presents later
• Structural lung defects (diaphragmatic hernia, pulmonary hypoplasia)

Question 2

RDS CXR findings

Answer 2

air bronchograms

ground glass

Question 3

RDS tx

Answer 3

1) Surfactant (with intubation)
2) CPAP == distention of airways
- or HFNC ~ PEEP.

Question 4

RFs for neonatal respiratory distress

Answer 4

• maternal diabetes
• prematurity (<36w) ==> lung immaturity, lack of surfactant
• maternal GBS ==> neonatal sepsis& respiratory distress
• C/S ==> transient tachypnea of the newborn (TTN)
• prolonged PROM (>/= 18h) ==> neonatal sepsis
• meconium in amniotic fluid ==> meconium aspiration syndrome

Question 5

what conditions is the apgar affected by?

what does it mean?
what does it NOT mean?

Answer 5

• gestational age
• maternal medications
• resuscitation
• cardiorespiratory & neurologic conditions in theinfant

documented asphyxia ==> poor neurologic outcome
dx = arterial blood gases for metabolic acidosis

NOT

• conclusive markers of acute intrapartumhypoxic event
• future neurological outcome of term infant

Question 6

Neonatal birth weight

- what does it mean

Answer 6

==> indicator of health of intrauterine environment

Plot: weight v. gestational age

Question 7

large for gestational age (LGA)

• define:
• etiology:
• potential clinical problems:

Answer 7

• define: birth weight > 90%ile
• etiology: constitutionally large; maternal T2DM/GDM
• potential clinical problems: complications with C/S, foreceps, vacuum extraction; birth injuries (fractured clavicle, brachial plexus injury, facial nerve palsy), perinatal hypoglycemia (chronic hyperinsulinemia)

Question 8

define: appropriate for gestational age (AGA)

- define:

Answer 8

birth weight 10%ile - 90%ile

Question 9

define: small for gestational age (SGA)
- define:
- etiology:
- potential clinical problems:

Answer 9

birth weight: 3%ile - 10%ile

• etiology: prematurity, constitutionally small (parental ethnicity, parity, weight/height)
• potential clinical problems: hypothermia, hypoglycemia (inadequate glycogen stores), polycythemia, hyperviscosity

Question 10

is SGA and IUGR the same thing?

Answer 10

no

SGA = small for gestational age
- at time of birth

IUGR= intrauterine growth restriction
- during pregnancy
==> has not reached growth potentail

Question 11

describe the transition from intrauterine to extrauterine life

Answer 11

1) FIRST BREATH = replace fluid with air ==> (a) fluid squeezed out during uterine contractiosn with vaginal delivery; (b) absorption by pulmonary lymphatics; (c) cry to force it out
(2) FIRST HOUR = elevated RR (40-60), HR (120-160)
(3) SECOND HOUR = elevated RR (60-80), HR (160-180)

Question 12

describe oxygenation in the fetus

• differentiate from newborn

Answer 12

FETUS = passive, placenta-provided source
- placental oxygenated blood from mother
==> UMBILICAL VEIN
==> liver, (1) ductus venosus
==> IVC
==> (2) PFO to LA ==> coronary, cerebral, upper body arteries; or to RV ==> lower body arteries

8-10% of blood from RV flow through

NEWBORN = active, respiration-based

Question 13

describe oxygenation in the fetus

• differentiate from newborn

Answer 13

FETUS = passive, placenta-provided source
- placental oxygenated blood from mother
==> UMBILICAL VEIN
==> liver, (1) ductus venosus
==> IVC
==> (2) PFO to LA ==> coronary, cerebral, upper body arteries; or to RV ==> lower body arteries
- 8-10% == pulmonary vaculature
- 90-92% ==(3) PDA ==> descending aorta

NEWBORN = active, respiration-based

Question 14

define: transient tachypnea of the newborn (TTN)

- prognosis

Answer 14

TTN = postnatal pulmonary edema

d/t delayed absorption of pulmonary fluid
- more common with C/S

==> continued improvement over next 12-24h
= will not likely recur

Question 15

diffdx: abnormal transition from intra to extrauterine life

Answer 15

• transient tachypnea of the newborn (TTN) == persistent postnatal pulmonary edema
• persistent pulmonary HTN of the newborn (PPHN) == persistence of fetal circulation

Question 16

signs of respiratory distress in a newborn

Answer 16

• tachypnea
• grunting == @ end-expiration ==> air being expelled thru partially closed glottis as infant attempts to increase transpulmonary pressures, increase lung volumes, improve gas exchange
• intercostal, subcostal retractions==d/t decreased lung compliance (primary lung pathology / pulm edema)
• increased respiratory effort

Question 17

conditions to consider in cyanotic newborn

common & uncommon

Answer 17

RESPIRATORY
(common)
- TTN
- RDS
(uncommon)
- pneumothorax
- diaphragmatic hernia
- choanal atresia
- pulmonary hypoplasia
- persistent pulmonary HTN of the newborn (PPHN)

CYANOTIC CONGENITAL HEART DEFECTS
(common)
- tetralogy of fallot
- transposition of the great arteries (esp. with GDM); usuallly associated with VSD.
(uncommon)
- truncus arteriosus
- tricuspid atresia
- total anomalous pulmonary venous  return
- pulmonary atresia

CNS

• hypoxic-ischemic encephalopathy
• intraventricular hemorrhage
• sepsis/meningitis

INFECTIOUS

• septic shock
• meningitis
• Respiratory depression 2/2 maternal medications
• hypothermia
• polycythemia/hyperviscosityt syndrome

Question 18

fetal effects of maternal hyperglycemia

Answer 18

maternal hyperglycemia

==> fetal hyperglycemia ==> stimulated fetal pancreatic beta cells; hyperinsulinemia

• T3 = increased growth of insulin-sensitive organ systems (heart, liver, muscle); fat synthesis & deposition ==> LGA
• appropriate size of other organs (brain, kidneys)

==> fetal malformations = DIRECTLY related to T1 HbA1c levels
- HbA1c > 12% == 12x increase in major malformations

==> respiratory problems

• RDS —> surfactant deficiency, delayed lung maturation
• TTN
• heart defects –> CHF

Question 19

does maternal insulin cross the placenta

Answer 19

no

but high levels of glucose in maternal serum ==> crosses placenta to stimulate insulin production in fetus

Question 20

what are the insulin sensitive organ systems

Answer 20

heart
liver
muscle

Question 21

what are the recommendations for feeding an infant with respiratory distress

Answer 21

CONCERNS

• greater stress
• breastfeeding interruption
• if RR 60-80 ==> oral feeds
• worsened respiratory distress with feeding ==> NG feeding +/- IV fluids
• RR > 80 ==> IV fluids +/- NG feeding
• mother should pump breasts as soon as possible after delivery ==> initiate milk production; ensure adequate supply when baby is able to feed
• infant fed with expressed breast milk +/- formula (esp in first 2-48h)

Question 22

define: neonatal hypoglycemia
- who is at risk
- physiology
- complications
- indications for intervention

Answer 22

• not precise definition; often asymptomatic
• at risk: SGA, LGA, late-preterm, infants of diabetic mothers (hyperinsulinemia)
• physio:
  1) UTERO: glucose crosses placenta ==> fetal BG = 2/3 maternal BG
  2) BIRTH: separation of placenta ==> (a) 1-2h of life = decline in infant glucose levels; (b) 3-4h of life = mean levels of 65-71mg/dL
  (esp. for hyperinsulinemic babies of diabetic mothers)

-complications (even asymptomatic) == negative long-term neurodevelopment

• indications for interventions (target prior to feed > 45mg/dL) ==> IV glucose
  1) symptomatic + BG <40mg/dL
  2) Asx in first 4h +post-prandial glucose < 25mg/dL
  3) Asx in 4-24h +post-prandial glucose < 35mg/dL

Question 23

evaluation of gestational age

Answer 23

Ballard score (+/- 2w)
- performed within 12-24h of life

Ballard = neuromuscular score + physical score

Question 24

Developmental dysplasia of thehip (DDH)
- sxs:
- RFs:
- screening recommendations:
-

Answer 24

== congenital dysplasia of the hip

• sxs: partial/complete dislocation; instability of femoral head
• RFs: breech position; female; Fhx
• screening recommendations
• serial clinical exams of ALL infants up to 6-12mo
• hip imaging (US) for female infants ONLY
  born in breach (optional for boys ONLY in breech, girls ONLY with positive family hx), <6mo

Question 25

diffdx for tachypnea in the newborn
==> causes
–> who is at risk

Answer 25

RDS (respiratory distress syndrome)
==>
d/t deficiency of lung surfactant, delayed lung maturation
–> in =37w gestation, infants of diabetic mothers (IDM)

TTN (transient tachypnea of the newborn)
==> delayed clearance of fluid from the lungs after birth
–> IDM; C/S; term & preterm

PNEUMOTHORAX
==> collection of gas in pleural space –> collapse of lung tissue
–> mechanical ventilation / underlying lung dz (meconium aspiration, severe infant RDS); premature infant with RDS

HYPOGLYCEMIA (w/ tachypnea being a non-specific response)
==> chronic hyperinsulinemic state
–> IDM; premature

CHF (congestive heart failure)
==> congenital heart defect –> early cardiac failure, tachypnea
==> IDM –> increase risk of heart defects

NEONATAL SEPSIS
==> infection with GBS from mother during labor –> (1) tachypnea, (2) rapidly more serious illness
–> prolonged PROM
** tachypnea may be the ONLY sign of early sepsis or pneumonia

PNEUMONIA

CONGENITAL DIAPHRAGMATIC HERNIA (usually L; bochdalek hernia posteriolaterally)
==> defect in development of diaphragm –> passage of abd organs into chest cavity –> pulmonary hypoplasia: absent breath sounds / prsence of bowel sounds on one side of chest

SEVERE COARCTATION OF THE AORTA
==> severe L ventricular outflow tract obstruction –> respiratory distress

MECONIUM ASPIRATION
==> in utero / at time of delivery –> respiratory distress, tachypnea

MATERNAL DRUG EXPOSURE

HYPOTHERMIA
==> low core temp –> tachypnea
–> premature newborns (small body size)

Question 26

what is the most common cause of respiratory distress in premature infants?

Answer 26

RDS (respiratory distress syndrome)

Question 27

what types of respiratory distress are more common in term infants? preterm?

Answer 27

term == TTN
+ infants of diabetic mothers (IDM); C/S

preterm == RDS, pneumothorax, hypoglycemia, hypothermia
+ (DM

Question 28

evaluation of a cyanotic newborn w/ respiratory distress

Answer 28

1) arterial blood gases –> oxygenation, ventilation, and acid base status
2) blood, CSF cultures–> concerns of sepsis; identify organism
3) CBC with differential –> neutropenia, leukopenia, abn immature-to-total neutrophil ratio, thrombocytopenia ==> SEPSIS
4) CXR –> HEART: size, shape; LUNGS: pneumonia, meconium aspiration, RDS, pneumothorax
5) ECHO –> congenital cardiac lesions; PPHN ==> for persistent cyanosis, no indication of lung dz, other signs of heart defect (murmur, abn ECG, CXR showing abn cardiac contour)
6) O2 challenge (hyperoxia) test: differentiate cardiac and pulm etiology ==> if RESPIRATORY - O2 suppl will increase PaO2; if CARDIAC- O2 suppl will not increase PaO2
6) physical exam –> identify cardiac murmurs, respiratory findings causing cyanosis [but some mrumursmay not present early in life d/t elevated pulmonary vascular pressure]
7) Pulse Ox

Question 29

cxr in neonate - how to assess inspiratory effort / hypo-hyperinflation?

Answer 29

8+ intercostal spaces of lung fields on both sides

Question 30

evaluation of a cyanotic newborn w/ respiratory distress

Answer 30

1) arterial blood gases –> oxygenation, ventilation, and acid base status
2) blood, CSF cultures–> concerns of sepsis; identify organism
3) CBC with differential –> neutropenia, leukopenia, abn immature-to-total neutrophil ratio, thrombocytopenia ==> SEPSIS
4) CXR –> HEART: size, shape; LUNGS: pneumonia, meconium aspiration, RDS, pneumothorax
5) ECHO –> congenital cardiac lesions; PPHN ==> for persistent cyanosis, no indication of lung dz, other signs of heart defect (murmur, abn ECG, CXR showing abn cardiac contour)
6) O2 challenge (hyperoxia) test: differentiate cardiac and pulm etiology ==> if RESPIRATORY - O2 suppl will increase PaO2; if CARDIAC- O2 suppl will not increase PaO2
6) physical exam –> identify cardiac murmurs, respiratory findings causing cyanosis [but some mrumursmay not present early in life d/t elevated pulmonary vascular pressure]
7) Pulse Ox

Question 31

cxr in neonate - how to assess inspiratory effort / hypo-hyperinflation?

Answer 31

8+ intercostal spaces of lung fields on both sides

Question 32

risk factors for hypoxemia

Answer 32

• shock
• severe sepsis
• CNS depression
• tachypnea
• perinatal asphyxia

Question 33

CXR: transient tachypnea of the newborn (TTN)

Answer 33

“wet” looking lungs
no consolidation
no air bronchograms

Significant perihilar streaking: interstitial fluid and engorged lymphatics.

Coarse, fluffy densities that represent fluid-filled alveoli.

Fluid in the pleural space and a small amount of fluid in the fissures on the lateral view

Question 34

risk factors for hypoxemia

Answer 34

• shock
• severe sepsis
• CNS depression
• tachypnea
• perinatal asphyxia

Question 35

CXR: transient tachypnea of the newborn (TTN)

Answer 35

“wet” looking lungs
no consolidation
no air bronchograms

Question 36

CXR: respiratory distress syndrome (RDS)

Answer 36

• diffuse reticulogranula apperarance (“ground glass”)

- air bronchograms

Question 37

management of hypoglycemia in the neonate

Answer 37

DX

1) (screen) glucometer <40mg/dL
2) (confirmatory) serum/plasma glucose

TREATMENT - glucometer or lab results of hypoglycemia

1) if able to take oral ==> breast/bottle feeding of pumped breast milk / formula +/- glucose ==> b/c more stable increase in glucose, w/out rebound hypoglycemia
2) if unable to intake adequate oral glucose ==> NGT + breast milk / formula; resume breast / bottle-feeding ASAP
3) Sxs –> IV dextrose ASAP
4) +/- D5W + asap breast milk / formula feeding
- concerns of only transient increase in blood glucose, then REBOUND HYPOGLYCEMIA within 1-2h if infant is hyperinsulinemia (IDM)

MONITORING (once feeds have been initiated)

• until BG >45mg/dL and stable
• q0.5-3h

Question 38

in an infant with hypoglycemia, why is it better to give breast milk than D5W?

Answer 38

BREAST MILK

• more reliable increase in glucose
• more stable increase in glucose
• NO rebound hypoglycemia

D5W

• need to give it with breast milk ASAP after
• transient increase in serum glucose
• REBOUND HYPOGLYCEMIA within 1-2h if infant is hyperinsulinemia (IDM)

Question 39

ADAM:
Birth history: C-section due to breech presentation at 36 weeks’ gestation, by dates

Normal fetal ultrasound at 20 weeks

Birth wt: 3600 grams (7.94 lbs)

Apgar scores were 8 at 1 minute and 9 at 5 minutes

Rupture of membranes 8 hours before delivery

No maternal fever

No meconium in the amniotic fluid

Mother is a 24-year-old diabetic with “fair” glucose control during the pregnancy. Her Group B strep status is unknown.

Initial vital signs were normal, but his respiratory rate has been increasing over the past hour. Current signs include:

HR: 130/minute

RR: 80/minute while at rest

Rectal temp: 36.5 C (97.7 F)

BP: 64/42 mm Hg (right arm)
Glucose at 1-hour check: 40 mg/dL

Which of the following are risk factors for Adam’s respiratory distress? Select all that apply.

A Mother is a 24 y.o. diabetic whose glucose control was “fair” during the pregnancy.
B Gestational age, by dates, is 36 weeks.
C Group B strep status is unknown.
D Membranes ruptured 8 hours before delivery. There was no maternal fever.
E There was no meconium in the amniotic fluid.
F Adam was delivered by c-section due to breech presentation.

Diffdx for tachypnea and respiratory distress

Answer 39

A, B, C, F

• maternal diabetes
• prematurity (<36w) ==> lung immaturity, lack of surfactant
• maternal GBS ==> neonatal sepsis& respiratory distress
• C/S ==> transient tachypnea of the newborn (TTN)
• prolonged PROM (>/= 18h) ==> neonatal sepsis
• meconium in amniotic fluid ==> meconium aspiration syndrome
• Infant respiratory distress syndrome (RDS)
• Transient tachypnea of the newborn (TTN)
• pneumothorax
• Hypoglycemia
• Congestive heart failure (CHF)
• Neonatal sepsis/pneumonia –> esp with GBS unknown, and premature
• Congenital diaphragmatic hernia
• severe coarctation of the aorta

Question 40

persistent pulmonary HTN of the newborn

• patho
• etiology
• sxs

Answer 40

== elevated pulmonary vascular resistant ==> venous blood bypass lungs; diverted through fetal channels (ductus arteriosus and foramen and ovale) in the systemic circulation ==> systemic arterial hypoxemia

• PFO: mixed blood between RA & LA/LV
• PDA: mixed blood between pulmonary artery & aorta
• etiology: meconium aspiration syndrome, diaphragmatic hernia, hypoplastic lungs, in utero asphyxia
• sxs:
• tachypnea
• tachycardia
• respiratory distress ==> expiratory grunting, nasal flaring
• generalized cyanosis
• low O2 levels (even while receiving 100% O2)

Question 41

newborn screening for congenital heart disease

Answer 41

1) Hypoplastic left heart syndrome
2) Pulmonary atresia
3) Tetralogy of Fallot
4) Total anomalous pulmonary venous return
5) Transposition of the great arteries
6) Tricuspid atresia, and
7) Truncus arteriosus

Question 42

newborn screening for congenital heart disease

Answer 42

1) Hypoplastic left heart syndrome
2) Pulmonary atresia
3) Tetralogy of Fallot
4) Total anomalous pulmonary venous return
5) Transposition of the great arteries
6) Tricuspid atresia, and
7) Truncus arteriosus

Question 43

what tests would not be reliable in the newborn period and why?

when would they be reliable?

Answer 43

esp. with concerns of sepsis.

1) serum electrolytes
2) serum calcium
==> newborn’s levels reflect mother’s status; effect of medications to mother during labor

==> infant’s status > 12-24h.

3) urine culture

==> infant’s status > 4d.

Question 44

Newborn hospital discharge considerations

Answer 44

• Physical examination without major defects
• Minimal or no jaundice = measured tbili prior to discharge; w/ observation for development of jaundice over next several days
• No blood group incompatibility
• Breastfeeding well every 2-4 hours, feeding 10-15min on each side
• Transition from meconium to seedy, soft, tan-yellow stools
• Weight loss < 10%
• Car seat available
• Good support for mother at home
• Back-to-Sleep program reviewed –>
• Prescription for vitamin D 400IU completed –> until infant is weaned to cow’s milk or formula in 6-12 mo.
• Follow-up arranged with an identified primary care physician –> w/in first week; if discharged <48h of life, f/up within 48h.
• Infant co-bedding reviewed –> should NOT share beds with other kids or parents during sleep (only for nursing/comforting), esp. when parent is very tired / sedating drugs. Can place bassonet / crib in parents’ room

Question 45

Newborn hospital discharge considerations

Answer 45

Dr. Martin asks you to review Adam’s current condition and decide if he is ready to be discharged home. Which of the following will you include in your decision making about discharge home? Select ALL that apply.

 Multiple Choice Answer:
A		Physical examination without major defects	
B		Minimal or no jaundice	
C		No blood group incompatibility	
D		Breastfeeding well every 2-4 hours	
E		Transition from meconium to seedy, soft, tan-yellow stools	
F		Weight loss < 10%	
G		Car seat available	
H		Good support for mother at home	
I		Back-to-Sleep program reviewed	
J		Prescription for vitamin D completed	
K		Follow-up arranged with an identified primary care physician	
L		Infant co-bedding reviewed

Question 46

Adam is a 2-hour-old infant born at 32 weeks’ gestational age via spontaneous vaginal delivery to a healthy mother with negative group B streptococcus status. There was no premature rupture of membranes and no meconium in the amniotic fluid. His Apgars were 8 at one minute and 9 at five minutes. Over the last two hours he has become progressively tachypneic. On physical examination he is large for gestational age. His vital signs are respiratory rate 75, temperature 36.5 C and heart rate is 130 beats per minute. His lung exam is remarkable for intercostal and subcostal retractions, grunting, and equal breath sounds. His heart exam reveals normal rhythm, normal S1 and S2, no murmurs, and normal peripheral pulses and capillary refill. Which of the following is the most likely cause of the patient’s condition?

A		Transient tachypnea of the newborn (TTN)	
B		Pneumothorax	
C		Congestive heart failure	
D		Respiratory distress syndrome	
E		Sepsis

Answer 46

D

Respiratory distress syndrome (RDS) causes tachypnea and is therefore an important consideration in this case. RDS is more common in premature infants. Given the lack of history of maternal diabetes, an NSVD birth, and few risk factors for sepsis other than prematurity, Adam is likely to have RDS.

NOT TTN
- more common in infants born to diabetic mothers. TTN is unlikely because he is 32 weeks, very premature, and was born via NSVD. RDS is much more likely, although TTN is still a possibility and would need to evaluated with a CXR

Question 47

A 3-hour-old infant boy, born by C-section at 36 weeks to a 30-year-old G1P1 with Apgars of 8 and 9 at 1 and 5 minutes, respectively, is found to be tachypneic in the newborn nursery. His mother has a history of Type II diabetes that was poorly controlled during her pregnancy. She was compliant with prenatal vitamins and took no other drugs during her pregnancy. Prenatal labs, including GBS, were negative. The mother’s membranes ruptured 9 hours prior to delivery, she was afebrile, and the amniotic fluid had no meconium. On physical exam, the infant is large for gestational age. He has good air movement through the lungs bilaterally, without retractions or nasal flaring. He appears well perfused with normal cardiac exam. He is not in a flexed posture and has a weak suck reflex. A screening test at 3 hours of life reveals blood glucose of 39 mg/dL. What is the most likely diagnosis?

A		Hypoglycemia	
B		Transposition of the great arteries	
C		Transient tachypnea of the newborn	
D		Neonatal sepsis	
E		Pneumothorax

Answer 47

A

ommon presentation in an infant born to a diabetic mother with poor glucose control during her pregnancy. The increase in maternal serum glucose stimulates fetal pancreatic beta cells to increase insulin production, and this hyperinsulinemic state leads to hypoglycemia when the placental glucose supply is discontinued after delivery. At < 4 hours of life, a glucometer reading of < 25 mg/dL without symptoms or < 40 mg/dL with symptoms would require intervention to correct the hypoglycemic state.

==> hypotonia, with absence of flexed posture and weak suck, and a blood glucose reading of 39 mg/dL, making hypoglycemia the most likely diagnosis.

Question 48

A male infant weighing 3200 grams is born to a G1P1 female at 39 weeks’ gestational age via planned C-section. Maternal PMH is unremarkable, and GBS status is unknown. Apgars are 7 and 8 at 1 and 5 minutes of life, respectively. The delivery is uncomplicated, and the infant initially appeared in good condition. However, one hour following delivery the infant develops increasing respiratory distress. RR is assessed as 90 breaths/min. All other vital signs are within normal limits. On exam, the infant is acyanotic with rapid respirations and robust capillary refill. Chest x-ray shows bilateral lung fields with the appearance of “a radio-opaque line of fluid in the horizontal fissure of the right lung.” No air bronchograms are noted. What is the most likely etiology of the infant’s respiratory distress?

A Transient tachypnea of the newborn (TTN)
B Respiratory distress syndrome (RDS)
C Neonatal sepsis
D Meconium aspiration

Answer 48

A

respiratory distress + cyanosis + SGA

residual fluid in the infant’s lungs following delivery, and usually resolves within several days. It is more common in babies delivered via C-section, as the normal mechanical force of labor that helps expel fluid from the lungs is lacking. Babies with TTN and other forms of respiratory distress are often unable to nurse and require feeding via NG tube until respiratory status stabilizes.

NOT meconium aspiration –> C/S

Question 49

what cause(s) of respiratory distress in newborns is associated with C/S

Answer 49

• TTN

Question 50

what cause(s) of respiratory distress in newborns is associated with vaginal delivery

Answer 50

• meconium aspiration

Question 51

Adam is a newborn male who was just born to a G2P1 mother at 36.2 weeks’ gestation via a vaginal delivery. The mother reports that she did not receive prenatal care because she did not have insurance. She says that she thinks her “water broke” about two days ago, but she did not have any contractions after that, so she decided not to come to the hospital. She did not start having contractions until 19 hours before she delivered. After delivery, Adam did not cry vigorously, was tachypneic, cyanotic, and febrile to 100.5 F. Amniotic fluid did not contain meconium. His chest x-ray is normal. Given Adam’s birth history, what is the most likely cause of his symptoms?

A Transient tachypnea of the newborn (TTN)
B Sepsis secondary to prolonged rupture of membranes
C Meconium aspiration syndrome
D Hypothermia
E Pneumothorax

Answer 51

B

prolonged PROM (>18h) =when the chorioamniotic membrane ruptures before the onset of labor. The main risks associated with PROM are preterm labor and delivery and neonatal sepsis. Adam’s mom said that her “water broke” two days ago, which indicates that she had PROM. Adam’s mother also did not receive prenatal care; therefore, she did not receive any of the prenatal screening tests that she should have, which increases the likelihood that she has an infection that could have potentially been transferred to Adam after the rupture of her membranes.

• history of PROM
• fever
• respiratory distress

Question 52

A newborn baby boy is born at 30 5/7 weeks’ gestation after induction of labor for the severe maternal preeclampsia. He is noted to have subcostal and intercostal retractions, grunting, nasal flaring, persistent cyanosis, and tachypnea 30 minutes after delivery. Apgars were 6 (–2 for color, –1 for breathing and –1 for tone) and 7 (–2 for color and –1 for breathing) at 1 and 5 minutes, respectively. Due to lack of prenatal care and the mother’s presentation with severe preeclampsia, betamethasone x 1 was given during induction, but she did not receive a second dose prior to delivery. A chest x-ray is obtained, which reveals diffuse ground-glass appearance and air bronchograms bilaterally. What is the most likely diagnosis?

A Meconium aspiration syndrome (MAS)
B Respiratory distress syndrome (RDS)
C Persistent pulmonary hypertension (PPHN)
D Transient tachypnea of the newborn (TTN)
E Bronchopulmonary dysplasia (BPD)

Answer 52

B

The baby boy is preterm, and his mother received only one dose of betamethasone, which puts him at increased risk for developing infant RDS, which is caused by insufficient surfactant. His physical exam and chest x-ray findings are consistent with RDS.

Question 53

meconium aspiration syndrome (MAS)

• define:
• sxs:
• RFs:
• pathophys:
• management
• prognosis

Answer 53

meconium aspiration syndrome (MAS)
- define: respiratory distress in newborns born through meconium-stained amniotic fluid whose sxs cannot be otherwise explained

• sxs
  1) mild RDS –> respiratory failure
  2) erythema toxicum
• RFs: thick meconium in amniotic fluid
• fetal hypoxia/stress; nonreassuring FHR tracing; postmature delivery (>41w); placental insufficiency, maternal HTN/preeclampsia, oligohydramnios, infection, acidosis, maternal tobacco/cocaine
• pathophys: occur in utero / prior to delivery of shoulders
  1) airway obstruction = complete (–> atelectasis); partial (–> air trapping, hyperdistension = “ball-valve effect” –> hyperinflation ==> pneumothorax, pneumomediastinum, pneumopericardium)
  2) surfactant dysfunction = meconium deactives and inhibits surfactant synthesis –> strips surfactant from alveolar surface = diffuse atelectasis
  3) chemical pneumonitis = w/in a few hours of aspiration –> gross VQ mismatch
  4) persistent pulmonary HTN of the newborn = chronic in-utero stress; thickening of pulmonary vessels –> further hypoxemia
  5) pulmonary infection
• management:
  1) resuscitation
  2) endotracheal intubation –> inadequate respiratory effort (gasping, labored breathing, poor oxygenation); HR (<100 bpm)
• prognosis = most have complete recovery of pulmonary fx / slightly increased incidence of respiratory infections in first year of life / reactive airway disease in first 6mo of life.

Question 54

are fetuses supposed to poop?

Answer 54

NO

–> predispose to meconium aspiration syndrome

Question 55

a baby is born with meconium-stained amniotic fluid. what do you NOT do? why?

Answer 55

VIGOROUS or NON VIGOROUS TERM INFANT

-DO NOT aspirate upper airways on the perineum to reduce risk of MAS –> delays time to resuscitation