Birth asphyxia occurs when the fetus is deprived of oxygen during or shortly after birth. It can cause complications including hypoxic ischemic encephalopathy, cerebral palsy, seizures, and death. Risk factors include prematurity, maternal infection, hypertension, and complications during labor or delivery that interrupt oxygen delivery to the fetus. Treatment involves resuscitation, monitoring for complications, controlling seizures, and in some cases therapeutic hypothermia. Preventing birth asphyxia requires close fetal monitoring and careful management of at-risk deliveries.

1. Birth asphyxia
1
JOSEPH GASPER KIMARO, MD
DAR ES SALAAM, TZ
11/28/13

2. 2
Introduction
Risk factors
Pathophysiology
Apgar scoring VS Birth Asphyxia
Management
Complications
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3. Introduction
3
• Birth asphyxia occur when the fetus is deprived of
an adequate supply of oxygen at birth.
–
Failure to initiate or maintain spontaneous resp at birth .
• Intrauterine Hypoxia is used to describe
inadequate oxygen availability during the gestation
period.
• Perinatal asphyxia a state of decreased oxygen
delivery to the fetus or neonate resulting in
inadequate tissue perfusion.
–
Common cause of perinatal death
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4. Introduction ct
4
BA may occur
1.
2.
3.
Immediately prior to(intrauterine),
During( intrapartum) or
Just after delivery(postpartum).
There is considerable controversy over the diagnosis
of birth asphyxia due to medicolegal reasons
Because of its lack of precision, the term is avoided
in modern obstetrics
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5. Requirements for resp
5
• Intact neuro and resp apparatus
• Clear airway
• Adequate alveolar area
• Expanded alveoli with surfactant
• Sufficient pulmonary perfusion
• Satisfactory lymphatic drainage
• Oxygen diffusion and dissociation capacity
• Carbonic anhydrase activity of the blood
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6. Why birth asphyxia?
6
10% NB need some
assistance
1% more adv
measures
717,000 (23%) NB
deaths related to
BA
Incidence for sev.
BA. 1/1000 V.S 510
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7. Where Tz stands
7
2.9miln NB deaths in
2012
1.8mln in 10 countries
alone making up
for 2/3
Same account for
nearly 57% of MD
worldwide
Tz , IMR 65.74 deaths
per 1,000 live births
and
NMR rate of 26 deaths
per 1000 live births in
2012
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8. Local findings
8
Hege et al 2012, Birth asphyxia , a major cause of neonatal mortality in Northern
Tanzania. (Journal American Academy of Paediatrics) prospective study at
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Haidomu

9. Risk factors for asphyxia..
9
ANTEPARTUM
–
–
–
maternal hypotension
Reduced maternal oxygenation
Inadequate placental perfusion/gas exchange
•
•
•
–
–
–
Maternal hypotension
Hypertension
Vascular diseases
Congenital infections/anomalies
IUGR
DM
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10. …
10
• INTRAPARTUM
– Interruption of umbilical circulation
•
•
•
–
True not
Cord prolapse
Cord avulsion
Inadequate placental perfusion/gas exchange
•
•
•
•
Abruptio
Ruptured uterus
Severe materna l hypotension
Abnornal uterine contractions
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11. 11

Traumatic deliveries



Abnormal maternal oxygenation





Breech delivery
Shoulder dystocia
Pulmonary edema
to prolonged labor
maternal sedation
premature infants
Severe cardiopulmonary abnormalities
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12. ….
12
POSTNATAL



Persistent pulmonary hypertension of the newborn
Severe circulatory insufficiency (eg, acute blood loss, septic
shock)
Congenital heart diseaseal
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13. …
13
When deprived of oxygen, either before or after
birth, infants demonstrate a well-defined sequence
of events leading to apnea
Oxygen deprivation results initially in a transient
period of rapid breathing.
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14. …
14
If such deprivation persists- primary apnea.


This stage is accompanied by a fall in heart rate and loss of
neuromuscular tone.
Simple stimulation and exposure to oxygen will usually reverse
primary apnea.
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15. …
15
If oxygen deprivation and asphyxia persist

the infant will develop deep gasping respirations followed by
secondary apnea.



a further decline in heart rate,
falling blood pressure,
loss of neuromuscular tone
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16. …
16
Infants in secondary apnea



will not respond to stimulation
will not spontaneously resume respiratory efforts.
Unless ventilation is assisted, death will occur
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17. ..
17
Clinically, primary and secondary apnea are
indistinguishable;


thus, secondary apnea must be assumed
resuscitation of the apneic infant must be started immediately.
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18. Apgar score Vs birth asphyxia
18
Apgar score-based on characteristics of





heart rate,
respiratory effort
, muscle tone,
reflex irritability,
and color
 assessed and assigned a value of 0 to 2
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19. ….
19
1-min As reflects the need for immediate
resuscitation.
5-min score


-effectiveness of resuscitative efforts.
prognostic significance for neonatal survival,
neonatal death


- 1 in 5000 (scores 7 to 10),
1 in 4( scores of 3 or less)
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20. ..
20
There has been erroneous definitions of asphyxia
and prediction for subsequent neurological outcome
basing upon low Apgar scores
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21. ..
21
certain elements of the Apgar score are partially
dependent on the physiological maturity of the
infant,

a healthy preterm infant may receive a low score only because
of immaturity
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22. …
22
Apgar scores may be influenced by a variety of
factors including,



fetal malformations,
maternal medications,
infection,
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23. ..
23
to equate the presence of a low Apgar score solely
with asphyxia or hypoxia represents a misuse of the
score
The Apgar score alone cannot establish hypoxia as
the cause of cerebral palsy
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24. Criteria for Neurological Injury to be related to
Asphyxia
24
• Profound metabolic or mixed acidemia (pH<7.0)
• Early onset of severe or moderate neonatal
encephalopathy in infants born at 34 or more weeks
of gestation
• Cerebral palsy of the spastic quadriplegic or
dyskinetic type
• Exclusion of other identifiable etiologies such as
trauma, coagulation disorders, infectious conditions,
or genetic disorders.
• Mulstisystem
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25. Management
25
Prophylactic




Antenatal high risk detection
Close fetal monitoring
Intrapartum use of electronic fetal monitoring
Judicious administration of anaethetics and sedatives during
labour
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26. Management
26
Definitive
Warmth
 Airway
 Suction
 drying
 tactile stimulation
- pulse, resp rate and colour

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27. 27
ABCDE resuscitation

A (air way)

B (breathing)

C (circulation)

D (drug)

E (evaluation)
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28. Complications of BA
28
BA can cause HIE


manifesting with-in 48 hours of birth
This results in an increased mortality rate, including an
increased risk of SIDS.
 Oxygen deprivation have been implicated in
 epilepsy
 Eating disorder
 Celebral palsy
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29. HIE classification sarnat and sarnat
29
• Grd1: Mild:
– hyperalert, hyperexcitable, normal muscle tone, no seizures
– sympathetic over-stimulation with tachycardia, dilated
pupils and jitteriness. EEG is normal
• Grd2: Moderate:
– hypotonia, decreased movements, coupious secretions
– EEG is abnormal and 70% of infants will have seizures
• Grd3: Severe:
– stuporous, flaccid, and absent primitive reflexes, usually
with seizures
– The infant may have seizures and has an abnormal EEG with
decreased background activity and/or voltage suppression.
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30. Mgt HIE-investigations
30
RBG
Serum Electrolytes
RFT
LFT
FBC
Sonography (Brain)
EEG
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31. MGT-HIE
31
Adequate resuscitation
Maintaion






Adequte ventilation
Adequate oxygenation
Adequate perfusion
Normal serum glucose
Fluid and electrolytes
Thermal neutral environment
Control seizures
Prevent cerebral oedema
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32. Mgt …
32
Lowering the core body temperature

begun within 6 hours of birth


effective therapy to reduce mortality
improve neurological outcome in survivors
Others
 Allopurinol
 Calcium chanel blockers
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33. Other Complications
33
RS: RDS, pulmonary hemorrhage
CVS: heart failure, cardiac shock,myocardial necrosis,
ventricular dysfunction
GIS: NEC, stress gastric ulcer, paralytic ileus
Renal:Oliguria, Anuria, acute tubular/cortical Necrosis Renal
failure
Liver: increase in Indirect bilirubin and decrease Clotting
factors
Hematologic: DIC, Thrombocytopenia
Metabolic: Acidosis, hypoglycemia, hypocalcemia,
hyponatremia, SIADH
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34. ..
34
Prevention of BA
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