Perinatal Asphyxia / Hypoxic Ischemic Encephalopathy

It is an insult to the fetus or newborn infant due to lack of oxygen (hypoxia) and/or a lack of perfusion (ischemia) to various organs
Hypoxic Ischemic Encephalopathy
H  : Lack of oxygen
I   : Lack of perfusion
E  : Damage to various organs
Incidence : 1 – 1.5% in term baby
Aetiology Of PNA
A. Antenatal cause
     1. Anoxic anoxia
          a. Pre-eclampsia
          b. Premature placental separation
          c. Prolonged labour
     2. Anaemia due to any cause
          a. Haemorrhage
          b. Rh incompatibility
          c. Fetal haemorrhage
     3. Stagnant hypoxia
          a. Umbilical cord compression
          b. Prolapse of the cord
          c. Knotting of the cord
          d. Twisting of the cord
B. Natal & post natal cause
     1. Postpartum haemorrhage
     2. Obstructed labour
     3. Severe anaemia
     4. Shock
Effects Of PNA
In 70 – 80% of cases brain is affected.
In mild PNA, 20 – 30% of cases organ dysfunction does not take place
Effects of PNA occurs due to lack of oxygen (Ischemia & perfusion)
A. In the brain
     1. Infarction
     2. Intracranial haemorrhage
     3. Seizure
     4. Cerebral oedema
     5. Hypotonia / Hypertonia
B. In the kidney
     1. Acute tubular necrosis leading to acute renal failure
C. In cardiovascular system
     1. Poor contractility
     2. Heart failure
     3. Myocardial infarction
D. In pulmonary system
     1. Respiratory distress syndrome
     2. Pulmonary infarction
     3. Pulmonary haemorrhage
E. In gastrointestinal tract
     1. Necrosis (Necrotizing enterocolitis)
     2. Haemorrhage
     3. Ulceration
G. Metabolic disorders
     1. Acidosis
     2. SIADH
     3. Hyponatraemia
     4. Hypocalcaemia
     5. Hypoglycaemia
H. In adrenal glands
     1. Haemorrhage (Waterhouse Friderichsen syndrome)
J. In blood
     1. Disseminated intravascular coagulation
K. In skin
     1. Subcutaneous fat necrosis
PNA is a multisystem & multiorgan disease
Severity & Grading Of PNA
It is determined by the degree of effects on the brain.
Importance Of Grading Of PNA
     1. For the management protocol
     2. For the assessment of prognosis
Traits
S1 – Mild
S2 – Moderate
S3 – Severe
1. Appearance
Awake

Irritable / Hyperactive

Lethergic

Movement is less

Unconscious & coma
2. Tone Normal Hypotonic Flaccid
3. Sucking of milk Normal / Weak
Vary / Absent

Ryle’s tube feeding is given

4. Seizure
+
++
5. Pupil Mydriasis Miosis Unequal pupil
6. Respiration Spontaneous respiration Spontaneous respiration with apnoea Periodic respiration with apnoea
7. Heart rate Tachycardia > 180 Bradycardia < 100 Variable
8. EEG Normal Abnormality detected Abnormality detected
9. Outcome 100% recovery 80% recovery
50% moratality

50% morbidity

Management Of Perinatal Asphyxia
It depends on the….
     1. Degree of staging
     2. Severity
     3. At the time of presentation
Immediate resuscitation of the baby
It is done in the delivery room immediately after birth, when the baby develops PNA.
Management is explained in a inverted shaped pyramid

Ⓐ Ⓑ Ⓒ Ⓓ should be performed in a thermoneutral environment (25 – 26 °C)
BMR is optimum at this temperature, so that the baby doesn’t gain or lose temperature
Other supportive treatment
It is done to give support to the organs affected, according to the patients need
1. Temperature should be maintained
2. Feeding the baby according to the need
3. Correction of fluid & electrolytes
4. Respiratory support
5. Anticonvulsants
6. Cardiotonic drugs
7. Antibiotics
PDF Format of this article can be downloaded from below.
Source : Prof. (Dr.) Didarul Alam. MBBS, DCH, MD, FCPS – USTC Lecture Notes
Latest posts by Dr. Pasindu Suriapperuma (see all)
0 0 vote
Article Rating
Subscribe
Notify of
guest
0 Comments
Inline Feedbacks
View all comments