Low Birth Weight Infants

Question 1

What is the definition of Low Birth Weight (LBW)?

Answer 1

Birth weight < 2.5 kg (5 lbs 8 oz)

Question 2

What is Very Low Birth Weight (VLBW)?

Answer 2

< 1.5 kg

Question 3

What is Extremely Low Birth Weight (ELBW)?

Answer 3

< 1 kg

Question 4

What is Critically Low Birth Weight?

Answer 4

< 0.75 kg

Question 5

What are the main types of LBW infants?

Answer 5

Preterm LBW, Term LBW, Small for Gestational Age (SGA/IUGR)

Question 6

Define Preterm baby.

Answer 6

< 37 weeks gestation

Question 7

Define Term baby.

Answer 7

37–41 weeks + 6 days

Question 8

Define Post-term baby.

Answer 8

≥ 42 weeks

Question 9

Definition of IUGR/SGA?

Answer 9

Birth weight <10th percentile or 2 SD below the mean for gestational age

Question 10

What is Symmetrical IUGR?

Answer 10

Wt, Length, and OFC all <10th percentile; due to early (1st trimester) insult; intrinsic causes

Question 11

What is Asymmetrical IUGR?

Answer 11

Wt <10th percentile; OFC & Length normal; due to late (2nd/3rd trimester) insult; extrinsic causes

Question 12

What is Large for Date (LGA)?

Answer 12

Birth weight > 4 kg

Question 13

Causes of Preterm Birth

Answer 13

Fetal:
Maternal:
Placental:
Uterine:
Others:

Question 14

Fetal causes

Answer 14

Multiple gestation

Congenital anomalies

Question 15

Maternal causes

Answer 15

Pre-eclampsia

Chronic illness (e.g. cyanotic heart disease, renal disease)

Infections (Listeria, Gp B Streptococcus , UTI, chorioamnionitis)

Drug abuse (cocaine)

Question 16

Placental:

Answer 16

Placenta previa
Abruptio placenta

Question 17

Uterine

Answer 17

Bicornuate uterus
Incompetent cervix

Question 18

Others:

Answer 18

PROM
Polyhydramnios
Iatrogenic causes
Previous preterm birth

Question 19

Causes of IUGR / SGA

Answer 19

Fetal:
Maternal:
Placental:

Question 20

Fetal:

Answer 20

TMR
Chromosomal: Trisomies

Infections: TORCH

Syndromes: Russell-Silver, Cornelia de Lange

Radiation

Multiple gestation

Question 21

Maternal:

Answer 21

Toxemia,
Hypoxemia (e.g. high altitude, cyanotic heart disease)
HTN, renal disease
Malnutrition, chronic illness
Drugs: narcotics, alcohol, smoking, cocaine

Question 22

Placental:

Answer 22

↓ placental weight or cellularity
Infarction
Abruption
Tumors (chorioangioma, hydatidiform mole)

Question 23

Clinical Signs: Premature vs Term Infant

Answer 23

Sole Creases
Breast Nodule
Scalp Hair
Earlobe
Testes/Scrotum
Female Genitalia

Question 24

Sole Creases

Answer 24

Preterm
- one or 2 transverse creases
- smooth posterior three fourths of foot

Term
- multiple creases
- anterior two thirds or the entire sole

Question 25

Breast Nodule

Answer 25

Preterm - 2mm or absent before 33 weeks Term - 4-7 mm

Question 26

Scalp Hair

Answer 26

Preterm - fine and woolly - fuzzy Term - coarse and silky - single stranded

Question 27

Earlobe

Answer 27

Preterm - no cartilage - folds easily Term - moderate to thick elastic cartilage - stiff

Question 28

Testes/Scrotum

Answer 28

Preterm - Partially descended, few rugae Term - Fully descended, many rugae

Question 29

Female Genitalia

Answer 29

Preterm - Prominent clitoris & labia minora Term - Labia majora covers clitoris

Question 30

Short-Term Complications

Answer 30

- CNS - CVS - Respiratory - GI - Haematology - Metabolic - Immunologic

Question 31

CNS complications in preterm infants?

Answer 31

Periventricular hemorrhage (esp. <33 wks) due to - immature brain and fragile vessels - poor autoregulation of cerebral blood flows

Question 32

CVS issues in preterms?

Answer 32

PDA, or reopening of DA common in infants with RDS and cause apnoea and bradycardia.

Question 33

Respiratory complications?

Answer 33

RDS (due to surfactant deficiency) Apnea of prematurity Aspiration risk (poor gag/cough, poor coordination)

Question 34

GI complications?

Answer 34

Paralytic ileus NEC (necrotizing enterocolitis): abd distension, bile-stained aspirate, bloody stools Feeding intolerance

Question 35

Hematologic issues?

Answer 35

Anemia of prematurity (↓ EPO) Thrombocytopenia (sepsis, hypothermia) Hyperbilirubinemia (immature liver) Vitamin E & K deficiencies

Question 36

Metabolic complications?

Answer 36

Hypothermia (larger skin surface area for weight, less well developed brown fat stores, reduced sub-cu fat stores ) Hypoglycemia ( deficient glycogen stores) Electrolyte issues: hyponatremia, hypokalemia, hypocalcemia, acidosis Rickets of prematurity

Question 37

Immune system issues?

Answer 37

Poor immunity (↓ IgG, complement), ↑ infections

Question 38

Long-Term Complications

Answer 38

ROP Major handicaps Sensory impairments Poor growth

Question 39

Eye complications in preterms?

Answer 39

Retinopathy of prematurity (ROP) — risk with <32 wks or <1.5 kg, O2 toxicity

Question 40

Major developmental issues?

Answer 40

Cerebral palsy Mental retardation Language disorders Learning disability, hyperactivity Cognitive delay

Question 41

Sensory issues

Answer 41

Squint Visual defects Hearing loss

Question 42

Growth issues?

Answer 42

Poor postnatal growth