Text Book Reading

Hipoxic Ischaemic Encephalopaty

PRESENTAN:

DANIEL E. R. MALAU

LECTURER:

PROF. DR. M. I. WIDIASTUTI, PAK, SP.S(K), M.SC

Definitions

Hypoxia or Anoxia: A partial (hypoxia) or complete (anoxia) lack of oxygen in the brain or blood

Asphyxia: The state in which placental or pulmonary gas exchange is compromised or ceases altogether

Ischemia: The reduction or cessation of bloodflow to an organ which compromises both oxygen and substrate delivery to the tissue

Hypoxic-Ischemic Encephalopathy: Abnormal neurologic behavior in the neonatal period arising as a result of a hypoxic-ischemic event.

Incidence of HIE

Occurs in 2-9 per 1000 live term births in developed countries

WHO : 0.5 – 1 per 1000 live term birth

Surabya (dr Soetomo Hospital ) : 12.25 % fro,m 3405 live term birth

Etiology of HIE

Maternal:

HYPERTENSION

Vascular Diseases

Diabetes

Uterine Ruptur

Uteroplacental:

Placental abruption

Cord prolapse

Uterine rupture

Fetal:

Anemia

Infectio

Severe isoimmune hemolytic disease

Cardiac arrhythmia

Patophysiology Hipoxic Ischemic Encephalopaty

PATHOPHYSIOLOGYPotential pathways for brain injury after hypoxia-ischemia.

Perlman J M Pediatrics 2006;117:S28-S33

©2006 by American Academy of Pediatrics

Clinical Staging of HIE (Sarnat and Sarnat, 1976)

Diagnosis

There is no clear diagnostic test for HIE Abnormal findings on the neurologic exam in the first few days

after birth is the single most useful predictor that brain insult has occurred in the perinatal period

Essential Criteria for Diagnosis of HIE: Metabolic acidosis (cord pH <7 or base deficit of >12)

APGAR SCORE 0-3 un first 5 minutes

Early onset of encephalopathy

Multisystem organ dysfunction

Assessment Tools in HIE

Amplitude-integrated EEG (aEEG)

When performed early, it may reflect dysfunction rather than permanent injury

Most useful in infants who have moderate to severe encephalopathy

Marginally abnormal or normal aEEG is very reassuring of good outcome

Severely abnormal aEEG in infants with moderate HIE raises the probability of death or severe disability from 25% to 75%

Assessment Tools in HIE

Evoked Potentials Brainstem auditory evoked potentials,

visual evoked potentials and somatosensory evoked potentials can be used in full-term infants with HIE

More sensitive and specific than aEEG alone

However, not as available as aEEG and there is a lack of experience among pediatric neurologists

Therefore aEEG is preferred because of easy access, application, and interpretation

Assessment Tools in HIE

Neuroimaging Cranial ultrasound: Not the best in assessing

abnormalities in term infants. Echogenicity develops gradually over days

CT: Less sensitive than MRI for detecting changes in the central gray nuclei

MRI: Most appropriate technique and is able to show different patterns of injury. Presence of signal abnormality in the internal capsule later in the first week has a very high predictive value for neurodevelopmental outcome

Differential Diagnosis

1. Analgesia during delivery

2. Viral, Sepsis, Meningitis

3. Kongenital Anomaly in central nervous system, heart and lung

4. Neuromuscular diseases

5. Trauma during delivery

THERAPY

1. Adequate Ventilation

2. Adequate Oxygenation,

3. Temperature Controlled : Head Cooling and Whole Body Cooling

4. Acidosis Metabolic Correction

5. Blood Glucose Controlled ( between 75-100 mg/dl)

6. Prevent Seizures

Management - Hypothermia

Has become standard of care

Whole-body and head-cooling available

Unclear if one regimen is superior to the other -

currently either one is utilized, based on availability

Aim to get core (rectal) temperature to 33-35º C for 72 hours

Hypothermia - Mechanism of Action

Reduces cerebral metabolism, prevents edema Decreases energy utilization Reduces/suppresses cytotoxic amino acid

accumulation and nitric oxide Inhibits platelet-activating factor, inflammatory

cascade Suppresses free radical activity Attenuates secondary neuronal damage Inhibits cell death Reduces extent of brain damage

DEATH OR SEVERE DISABILITY AT 18 MONTHS OF AGE SIGNIFICANTLY REDUCED!!

Criteria for Hypothermia

Hypothermia is not effective for every baby

Currently only used in infants > 35 weeks Time interval between birth and initiation of

treatment important

Treatment must be started within 6 hours of birth to be effective

HYPOTHERMIA

1. HEAD COOLING 2. WHOLE BODY COOLING

HEAD COOLING WHOLE BODY COOLING

Pharmacologic Management

Allopurinol

Some trials have shown a decrease in mortality and a beneficial effect on free radical formation, cerebral blood flow and electrical brain activity

Meta-analysis concluded that more trials need to be done using allopurinol as an adjunct to hypothermia to make a conclusion on its effectiveness in treating HIE

Pharmacologic Management

Opioids

A few studies have demonstrated that morphine and fentanyl may have a neuroprotective effect after HIE with less severe signs of brain damage on MRI at 7 days of life and better neurologic outcomes at 13 months of age

However, long term effects of these medications are not known and more prospective randomized trials are warranted.

Prognosis

It is variated , from mild to severe :

1. Severa asphyxia

2. Seizures that cant controlled for 12 hours or more

3. Multi Organ Failure

4. Neurological problem that persisten

5. Persisten Oliguria

Microcephaly

Severe Abnormality in EEG

Ct Scan Severe Haemmorhage, periventrikel leukomalasi (PVL) atau nekrosis.

MRI 24-72 hours after birth.

THANK YOU