PBL 3

Question 1

describe the score system for Apgar

Answer 1

appearance
0 pale
1 Body pink, extra blue
2 all pink

pulse
0 absent
1 less than 100
2 over 100

griamce
0 no response
1 grimace
2 cry

activity
0 limp
1 some flexion
2 active motion

respiration effort
0 absent
1 slow cry
2 good cry

Question 2

what does the response to resuscitation results based on

Answer 2

• Neurological status.

* Effects on other systems.

Question 3

What is the sarnat score

Answer 3

grading system for hypoxic effects on the brain (usually carried out at 24 hours).
• Can be used as a broad outcome

Question 4

what grades is the sarnat score made out of

Answer 4

Grade I
Grade II
Grade III

Question 5

describe the sarnat scoring system

Answer 5

Grade I: hyper alert, tachycardic, jittery, hyper-reflexic, dilate pupils and no fits.
• 100% survive and are usually neurologically normal.

Grade II: lethargic, not comatose, bradycardic, hypotonic, convulsions.
• 5% will die, 20% of survivors will have some neurological deficit.

Grade III: flaccid, stuporose (near-unconscious), poorly reacting pupils, prolonged fits.
• 75% will die, 100% of survivors will have neurological deficit.

Question 6

what happens in grade III of the sarnat score and what is the prognosis confirmed by

Answer 6

If the baby falls into grade III it a poor prognosis can be expected (with severe neurological deficit).
• Confirmed by MRI  shows significant areas of possible infarction

Question 7

what is the baby at high risk of development of

Answer 7

Baby is at very high risk of going on to develop microcephaly and spastic quadriplegia, difficult to control fits, learning difficulties and feeding difficulties (overall hypoxic-ischaemic encephalopathy).

Question 8

What is the role of hypothermia in the treatment of hypoxic-ischaemic encephalopathy

Answer 8

o Involves the baby being cooled at a temperature of 33 to 34 degrees for 72 hours followed by a slow rewarming of 0.5 degrees per hour.
o It decreases cerebral metabolism, decreases energy use, decreases accumulation of excitotoxicity amino acids and decrease NO synthase/free radical activity.
• i.e. tries to prevent secondary energy failure.

Question 9

what specific does hypothermia do to the brain

Answer 9

o It decreases cerebral metabolism, decreases energy use, decreases accumulation of excitotoxicity amino acids and decrease NO synthase/free radical activity.

Question 10

Ventouse

Answer 10

a cup-shaped suction device applied to the baby’s head in childbirth, to assist the birth

Question 11

Meconium

Answer 11

dark green substance forming the first faeces of the infant.

Question 12

Apgar score

Answer 12

measure of physical condition of a newborn infant.

Question 13

Phenobarbitone

Answer 13

barbiturates (cause prolonged receptor opening of GABAA receptors).

Question 14

What is the prevelance of birth asphyxia

Answer 14

birth asphyxia accounts for 7-10% of cases of severe neurological handicap
• There is no uniform definition but reported rates of birth asphyxia are 3-9/1000 births.

Question 15

what is a poor indication of birth asphyxia

Answer 15

At birth a poor Apgar score is most widely used as an indicator of birth asphyxia.

Question 16

What are the indications of birth asymphixa

Answer 16

•	Prolonged time to onset of spontaneous respirations.
•	Low umbilical vessel blood pH.
•	Abnormal fetal heart rate patterns.
•	Abnormal neonatal neurological signs. 
-      poor agar score

Question 17

what are the fetal rate tracing signs of hypoxia

Answer 17

• Flat trace (loss of beat-to-beat variation
• Tachycardia: >160/mt.
• Bradycardia: <110/m.

Question 18

What is a type I dip

Answer 18

• Type I dips: decelerations which occur with contractions.
 Also, known as early decelerations.
o Immediately recovers when contraction is over
o Due to head compression (normal).

Question 19

What is a type II dip

Answer 19

• Type II dips: decelerations which persist after contraction.
o Due to uteroplacental insufficiency (UPI).

Question 20

What is an unprovoked dip

Answer 20

• Unprovoked dips: decelerations not associated with uterine contractions (variable dips).
o Associated with umbilical cord compression.

Question 21

What are the 3 types of dip

Answer 21

Type I dip
Type II dip
unprovoked dip

Question 22

what criteria has to be met for a obstetric forceps or venous extractor be used

Answer 22

• Full cervical dilation.
• Engaged fetal cephalic presentation.
• Ruptured membranes.
• Empty bladder.
• No pelvic contracture/obstruction to fetus.
• Adequate analgesia.
• Experienced deliverer.

Question 23

what happens if you don’t meet the criteria for an obstetric forceps or venous extractor

Answer 23

proceed to Caesarean section

Question 24

what can inappropriate use of obstetric forceps or a venous extractor lead to

Answer 24

• Pelvic soft tissue injuries.
• Fetal cranial fractures.
• Nerve plexus trauma.

Question 25

what is meconium

Answer 25

• Contained within the fetal bowel (made up of desquamated bowel cells and bowel secretion).
o It is a green/black colour and is of a thick consistency.

Question 26

what is meconium made out of

Answer 26

made up of desquamated bowel cells and bowel secretion)

Question 27

what happens in asphyxia to the meconium

Answer 27

• Asphyxia can cause the fetus to evacuate the bowel allowing meconium to pass into the liquor
o This may prevent onset of normal respiration.
 Baby will remain hypoxic and normal process of physiological change from fetal to neonatal circulation will fail to occur.

Question 28

what are the respiratory changes occurring at birth

Answer 28

• Initial first gaps generate negative intra-thoracic pressure (as low as -60 to 90 cm H20)
• Air fills the lung and much of the fetal lung fluid is expelled.
• Remainder is absorbed into the pulmonary lymphatics/capillaries

Question 29

what causes the ductus arteriosus to occur

Answer 29

• Oxygen levels (PaO2) increases from 2-3.5 kPa in the fetus to 9-13 kPa in the first few breaths. This hyperoxia causes the ductus arteriosus to close.
o Some babies = have murmur in first day that disappears as ductus closes

Question 30

what keeps the ductus arteriosus open in utero

Answer 30

• In utero: ductus is kept open under the influence of prostaglandin E1, but the influence declines as term approaches.
o This decline causes the smooth muscle of the ductus to constrict

Question 31

What is pulmonary vascular resistance

Answer 31

there is a marked fall in pulmonary vascular resistance shortly after birth (so pulmonary blood flow increases

Question 32

what happens to the foramen ovale

Answer 32

There is also a drop-in pressure on the right side of the heart, so there is no shunting through foramen ovale (is firstly reversed before it closes to allow for oxygenated blood in systemic circulation).

Question 33

what happens to the ductus venous

Answer 33

decrease in blood flow in inferior vena cave = ductus venosus is closed and becomes the ligamentum teres

Question 34

what happens to the umbilical vessel

Answer 34

close and fuse within 10 days.

Question 35

describe the timings of functional and anatomical closure of

• umbilical vessels
• ductus arteriosus
• ductus venous
• foramen ovale

Answer 35

Functional

• Umbilical vessels = 5 minutes
• Ductus arteriosus = 12 hours
• Ductus venous = 1-3 weeks
• foramen ovale = varaible

anatomical

• umbilical vessels = 10 days
• ductus arteriosus =4-7 days
• ductus venous = 1-3 weeks
• foramen ovale = 6 months - never

Question 36

what is the effects of apraxia on circulation

Answer 36

• Results in poor O2 delivery to vital organs and can lead to multi-organ failure.
o Baby can die from renal failure, hepatic failure or cardiac failure

Most elaborate manifestations: seen in the neurological system.
• Ranges from sings of irritability to fits/coma.

Question 37

when is the Apgar score tested

Answer 37

• Used to quickly asses the health of an infant one to five minutes after birth using 5 components and scoring these from 0-2.