Prematurity and Common Problems with Premature Newborns

Question 1

What is the official definition for premature infants?

Answer 1

< 37 weeks gestation

Question 2

What is the weight difference between Low Birth Weight (LBW), Very low birth weight (VLBW), and Extremely low birth weight (ELBW)?

Answer 2

LBW: < 2500 grams
VLBW: < 1500 grams
ELBW: < 1000 grams

Question 3

What is the definition of an Extremely low gestational age neonate (ELGAN)?

Answer 3

< 28 weeks gestation

Question 4

What gestation age is at greatest risk of RDS development?

Answer 4

< 34 weeks gestation

Question 5

At what gestational age does surfactant production start, and what age does a child produce mature levels of surfactant?

Answer 5

Starts = 24-29 weeks gestation

Mature lvls = 34-35 weeks gestation

Question 6

What is the pathophysiology of Respiratory Distress Syndrome in a premature infant?

Answer 6

caused by insufficiency of lung surfactant due to immaturity of type 2 pneumocytes = alveoli collapse due to high surface tension

Question 7

What maternal risk factor puts premature newborns at a higher risk of developing RDS?

Answer 7

Maternal DIABETES

• maternal glucose crosses placenta (NOT INSULIN) and fetus increases insulin production
• fetal insulin levels rise and cause negative feedback on surfactant production (glucose important in surfactant synthesis)

Question 8

What testing can be done to predict a developing fetus’s likelihood of developing NRDS?

Answer 8

FLM = Fetal Lung Maturity testing

• measures concentration of surfactant components in amniotic fluid
• obtained through amniocentesis

Question 9

Why can C-sections increase the risk of neonatal RDS?

Answer 9

Removes the stress placed on the neonate during birth

• stress = increased cortisol levels = increased surfactant production

Question 10

What is an air bronchogram?

Answer 10

air-filled bronchi seen on radiograph within spaces of consolidation

“black bronchi on white lung consolidation”

Question 11

What are the PaO2, PaCO2, and pH ranges that an infant with NRDS should be maintained within?

Answer 11

PaO2 = 50-80 mmHg
PaCO2 = 40-55 mmHg
pH = > 7.25

Question 12

What is seen on CXR of a child with NRDS?

Answer 12

“ground glass” opacities and air bronchograms

Question 13

What are the mainstay treatment options for NRDS patients?

Answer 13

CPAP –> intubation/mechanical ventilation (refractory to CPAP)
Exogenous surfactant (through ETT)

Question 14

What are the goal SpO2 and PaCO2 ranges for NRDS patients receiving CPAP?

Answer 14

SpO2 = 90-95%
PaCO2 = 45-65 mmHg

Question 15

What is the pathophysiology of Bronchopulmonary Dysplasia (BPD)?

How is it diagnosed?

Answer 15

barotrauma and reactive oxygen species damage lung tissue in premature lungs, causing exaggerated inflammatory response that impairs normal lung development

Dx: need for supplemental oxygen > 28 days of life

Question 16

Which neonates are more likely to develop BPD?

Answer 16

those born 23-32 weeks or that weight < 1250 grams at birth

Question 17

What is the typical treatment for newborns with BPD?

Answer 17

• increase calorie intake and limit fluid intake
• NONINVASIVE oxygen support (wean over 2-4 months)
• can consider diuretics, systemic corticosteroids, or bronchodilators

Question 18

What is the most common GI emergency in premature infants?

Answer 18

Necrotizing Enterocolitis

Question 19

What week(s) of life is NEC most likely to develop?

Answer 19

2nd-3rd week of life

Question 20

What is the reason that causes NEC to develop in premature infants?

Answer 20

likely due to immaturity of the gut, leading to inflammation, bowel ischemia, and possible perforation of the bowel wall

• typically develops following introduction of feeds

Question 21

What is the management of NEC patients without signs of perforation?

Answer 21

NPO, nasogastric decompression, IV fluids + TPN, Blood cultures + Abx (cover anaerobes)

• surgery if perforation, pneumoperitoneum, failure of medical treatment

Question 22

What are the two biggest risk factors for the development of NEC in premature infants?

Answer 22

prematurity and formula feeding

• human milk is PROTECTIVE against NEC

Question 23

Ophthalmology evaluation is necessary for all premature infants with what two criterion, in order to screen for Retinopathy of Prematurity?

Answer 23

1. weight < 1500 grams
2. gestational age < 30 weeks

Question 24

What are some of the treatment modalities that can be used to treat retinopathy of prematurity?

Answer 24

cryotherapy, PHOTOABLATION, anti-VEGF agents

Question 25

What is the pathophysiology of Retinopathy of Prematurity?

Answer 25

abnormal proliferation of immature retinal vessels in premature newborns receiving oxygen therapy

• can lead to blindness and retinal detachment

Question 26

When do most IVHs occur?

Answer 26

within 72 hours after birth

Question 27

All infants born before 30 weeks gestation should have what done to screen for IVH?

When should these infants receive their second round of screening?

Answer 27

cranial ultrasound 7-14 days after birth

second screening: 36-40 weeks postmenstrual age

Question 28

What is the difference in location between Grade I-IV IVHs?

Answer 28

Grade 1: into germinal matrix
Grade 2: < 50% lateral ventricle
Grade 3: > 50% lateral ventricle
Grade 4: periventricular white matter infarct

Question 29

What is the method of treatment for patients with IVH?

Answer 29

Goal: correct underlying condition that lead to development of IVH (RDS, shock, etc)

• if hydrocephalus present –> ventriculoperitoneal shunt can be placed