Jaundice

Question 1

What is the normal level of bilirubin in an infant

Answer 1

Less than 35umol/l

Question 2

What is the level where the bilirubin becomes dangerous

Answer 2

Above 200umol/l

Question 3

Why is a baby most susceptible to jaundice in the first week

Answer 3

This is because in utero the baby keeps its bilirubin unconjugated so that it can be passed to the mother through the placenta thus the baby’s liver enzymes are not as effective at conjugation until the first week. The babies intestines also contain enzymes that deconjugated the bilirubin

Question 4

What causes increased production of bilirubin 4

Answer 4

1. Cephalohaematoma
2. Polycythemia
3. Infection
4. Haemolytic disease

Question 5

What are 3 possible causes of slow conjugation

Answer 5

1. Slow initiation of the enzymes in the liver
2. Preterm infants are born before the liver enzymes are ready
3. Congenital hypothyroidism: Causes slowing of the maturation of the liver

Question 6

What are the 2 possible causes of decreased secretion

Answer 6

1. Hepatitis: Infection
2. Billary atresia

Question 7

What is meant by physiological jaundice

Answer 7

14 days of increased bilirubin after the birth of the infant

Question 8

What are the 4 conditions that must occur for ABO hemolytic disease to occur

Answer 8

1. The mother should be O
2. The father must be A, B or AB
3. The infant must be A or B
4. The Coombs test must be positive

Question 9

What is the dose of anti-D immunoglobulins that are given to prevent maternal sensitization

Answer 9

100ug

Question 10

What makes prem babies more susceptible to high bilirubin levels

Answer 10

They have improperly formed BBB

Question 11

What are some of the risk factors that place infants at risk for bilirubin encephalopathy 3 and why do these occur

Answer 11

1. Hypoxia
2. Hypoglycemia
3. Infection
   These all increase the permeability of the BBB

Question 12

Which infants should get phototherapy

Answer 12

Any infant with a TSB of above 80 after 6 hours

Question 13

What are the ranges of phototherapy in a prem infant

Answer 13

1. Less than 1250g above 125
2. Less than 1500g above 150
3. Less than 2000g above 200

Question 14

What is the main risk factor of phototherapy

Answer 14

The infant can become dehydrated due to the increased passage of stools

Question 15

What is bronzing and how does it occur

Answer 15

This is when an infant that has an issue in excretion conjugated bilirubin e.g. in biliary atresia is placed under phototherapy and so the unconjugated is converted but there is still no excretion of the conjugated

Question 16

What is important to remember even after the visible jaundice disappears in phototherapy

Answer 16

That the infant might still have high levels of TSBW

Question 17

What is the benefit of phenobarbitone

Answer 17

It shows little benefits and makes the infant lethargic

Question 18

What are the 4 main indications for an exchange transfusion

Answer 18

1. A TSB above 400 despite phototherapy
2. A TSB in preterm between 250 and 350
3. Rapidly rising TSB
4. When there is high TSB and the presence of infection, hypoxia, hypoglycemia, or hypothermia

Question 19

What is considered the normal values for anemia

Answer 19

1. Packed cell volume: 45-65%
2. HB: 15 - 25g/dL

Question 20

What is considered an anemia

Answer 20

Below 35%, 12g/dL

Question 21

Why do premature babies have a fall in their HB 3

Answer 21

1. They have underdeveloped kidneys that produce low amounts of EPO
2. The fetal RBC has a shorter lifespan
3. Infants have low iron because most of the iron transfers in the tritrimester

Question 22

When should treatment with packed red blood cells be given to a premature baby

Answer 22

If the Hb falls below 8.5 or the PCV is below 25%

Question 23

What are the 2 criteria for polycythemia

Answer 23

1. PVC of more than 65%
2. An Hb Above 25g/dL

Question 24

What are the 3 possible causes of polycythemia

Answer 24

1. Chronic fetal hypoxia
2. Maternal diabetes
3. Over transfusion: This can be twin to twin or iatrogenic