Complete definition of Hypoxic Ischemic Encephalopathy, clinical manifestations according to Sarnat staging system, risk factor, pathophysiology and details of management and approaches to be used.
2. Outline
At the end of presentation you will be able to:
• Recall definition, pathophysiology, symptoms of HIE.
• Recommend appropriate treatment plan.
• Discuss management of HIE.
• Identify future prospect medications.
2
3. Background
• Despite major advances in monitoring technology and knowledge of
fetal and neonatal pathologies, perinatal asphyxia or, more
appropriately, hypoxic-ischemic encephalopathy (HIE), remains a
serious condition that causes significant mortality and long-term
morbidity.
• HIE is characterized by clinical and laboratory evidence of acute or
subacute brain injury due to asphyxia (i.e., hypoxia, acidosis). Most
often, the exact timing and underlying cause remain unknown.
3
Neonatal hypoxic ischemic encephalopathy. ucsfbenioffchildrens.org. (n.d.). Retrieved April 28, 2022, from https://www.ucsfbenioffchildrens.org/conditions/neonatal-
hypoxic-ischemic-encephalopathy#:~:text=Hypoxic%20ischemic%20encephalopathy%20(HIE)%20is,and%20encephalopathy%20means%20brain%20disorder.
4. Definition
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Ohio hie lawyers pursue brain damage claims on behalf of newborns. Ohio HIE Lawyers | Infant Hypoxic Ischemic Encephalopathy. (n.d.). Retrieved April 28, 2022, from
https://www.birthinjuryohio.com/brain-injuries/hie/
5. Assessment
Apgar score of <5 at 5 minutes and 10 minutes
Fetal umbilical artery pH <7.0, or base deficit ≥12
mmol/L, or both
Acute brain injury seen on brain MRI
Presence of multisystem organ failure (kidney, lung,
liver, heart,…)
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Assessment of Hypoxic ischemic Encephalopathy. Retrieved April 28, 2022, from https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(18)30051-
8/fulltext
6. Clinical Feature
Abnormal state of consciousness (hyper-alert, irritable, lethargic, or obtunded)
Diminished spontaneous movements
Weak or absent cry
Respiratory or feeding difficulty
Poor tone
Abnormal posturing
Abnormal primitive reflexes
Seizures
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Allen, K. A., & Brandon, D. H. (2011, September 1). Hypoxic ischemic encephalopathy: Pathophysiology and experimental treatments. Newborn and
infant nursing reviews : NAINR. Retrieved April 28, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3171747/
7. 7
Clinical Feature – Sarnat Staging System
Severity of hypoxic ischemic encephalopathy ... - researchgate. (n.d.). Retrieved April 28, 2022, from
https://www.researchgate.net/publication/334575225_Severity_of_hypoxic_ischemic_encephalopathy_and_heart_rate_variability_in_neonates_A_systematic_review/fulltext/5d31fed5a6fdcc370
a4e8f7c/334575225_Severity_of_hypoxic_ischemic_encephalopathy_and_heart_rate_variability_in_neonates_A_systematic_review.pdf
10. Pathophysiology
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• Birth Injury: an injury that occurred
during the process of birth
• Birth Asphyxia: asphyxia that occurred
during 2nd and 3rd stages of labor
• Perinatal Asphyxia: asphyxia that
occurred anytime between
conception to first month of life.
11. 11
Pathophysiology (Con’t)
Santina A Zanelli, M. D. (2021, April 3). Hypoxic-ischemic encephalopathy. Practice Essentials, Background, Pathophysiology. Retrieved April 28, 2022, from
https://emedicine.medscape.com/article/973501-overview
12. Intervention and Therapies
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Criteria
• Gestational age ≥36 weeks and ≤6 hours of age
And one of the following:
1. Metabolic or mixed acidosis with a pH of ≤7.0 or a base
deficit of ≥16 mmol/L in a sample of umbilical cord blood or
any blood obtained within the first hour after birth
2. A 10-minute Apgar score of ≤5
3. Ongoing resuscitation (eg, assisted ventilation, chest
compressions, or cardiac medications) initiated at birth and
continued for at least 10 minutes
• Moderate to severe encephalopathy on clinical examination
Guideline: Hypoxic ischaemic ... - queensland health. (n.d.). Retrieved April 28, 2022, from https://www.health.qld.gov.au/__data/assets/pdf_file/0014/140162/g-hie.pdf
13. Therapeutic Hypothermia
• Must be initiated within 6 hours of birth
• All external head sources off
• Desired temperature: 33.5 ± 0.1 Centigrade
• Monitor temperature every 15 minutes
• Maintain for 72 hours
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Intervention and Therapies
Guideline: Hypoxic ischaemic ... - queensland health. (n.d.). Retrieved April 28, 2022, from https://www.health.qld.gov.au/__data/assets/pdf_file/0014/140162/g-hie.pdf
14. Whole Body Head Only
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Intervention and Therapies
Therapeutic Hypothermia
Guideline: Hypoxic ischaemic ... - queensland health. (n.d.). Retrieved April 28, 2022, from https://www.health.qld.gov.au/__data/assets/pdf_file/0014/140162/g-hie.pdf
15. 1. Reduce metabolic rate and energy depletion.
2. Decrease excitatory transmission release.
3. Reduce alteration in ion flux.
4. Reduce apoptosis due to Hypoxic-Ischemic Encephalopathy
5. Reduce vascular permeability, edema, and disruption of BBB function.
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Intervention and Therapies
Therapeutic Hypothermia
Abate, B. B., Bimerew, M., Gebremichael, B., Mengesha Kassie, A., Kassaw, M. W., Gebremeskel, T., & Bayih, W. A. (2021). Effects of therapeutic hypothermia
on death among asphyxiated neonates with hypoxic-ischemic encephalopathy: A systematic review and meta-analysis of Randomized Control Trials. PLOS ONE,
16(2). https://doi.org/10.1371/journal.pone.0247229
16. Recommended lab
Glucose
CBC
Blood
culture
PT, PTT,
Fibrinog
en
ABG
LFTs
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Intervention and Therapies
Therapeutic Hypothermia
Douglas-Escobar, M., & Weiss, M. D. (2012, November 2). Biomarkers of hypoxic-ischemic encephalopathy in newborns. Frontiers in neurology. Retrieved April
28, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3486976/
17. Arrhythmia
• Bradycardia
• Ventricular tachycardia
Thrombocytopenia
Persistent acidosis Bleeding
Subcutaneous fat
necrosis ±
hypercalcemia
Death
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Intervention and Therapies
Therapeutic Hypothermia’s Complication
Texaschildrens.org ▷ Texas Children's Hospital. Webrate. (n.d.). Retrieved April 28, 2022, from https://webrate.org/index.php/site/texaschildrens.org/
18. • Warm slowly after 72 hours
Monitor very closely
• Increase temperature by 0.5 degree every hour
Until reach 36.5
• Once temperature reaches 36.5 for 1 hour
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Intervention and Therapies
Rewarming
Texaschildrens.org ▷ Texas Children's Hospital. Webrate. (n.d.). Retrieved April 28, 2022, from https://webrate.org/index.php/site/texaschildrens.org/
19. Supportive Management
• Aside from treatment with therapeutic hypothermia, suggested
management of neonatal encephalopathy includes the following
recommendations:
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Treat Seizure
Phenobarbital
Phosphenytoin
Lorazepam
Levetiracetam
Ventilation
Inhaled NO
Extracorporeal
membrane
oxygenation
Replace volume
Use of inotropes
Metabolic
disorder
Stop feeding
Correct acidosis
Vitamin
supplementation if
needed
Maintain
Euglycemia
Guideline: Hypoxic ischaemic ... - queensland health. (n.d.). Retrieved April 28, 2022, from https://www.health.qld.gov.au/__data/assets/pdf_file/0014/140162/g-hie.pdf
20. Follow – Up
Developmental
pediatric consult &
evaluation prior to
discharge
Neurology clinic
post discharge
Brain MRI at 1 year
of age
Developmental
clinic at 6 months, 1
year, and 18 months
(Bayley exam)
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Texaschildrens.org ▷ Texas Children's Hospital. Webrate. (n.d.). Retrieved April 28, 2022, from https://webrate.org/index.php/site/texaschildrens.org/
21. Promising Drugs
• Reduces apoptotic, inflammatory and oxidative brain
injury.
Erythropoietin
• Antioxidant, antiapoptotic, cross BBB,
neuroprotective
Melatonin
• Precursor of glutathione which is act as antioxidant
N-Acetylcycteine
(NAC)
• Antioxidant, inhibitor of superoxide and hydrogen
peroxide production
Allopurinol
21
Nair, J., & Kumar, V. H. S. (2018, July 19). Current and emerging therapies in the management of hypoxic ischemic encephalopathy in neonates. Children (Basel,
Switzerland). Retrieved April 28, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6069156/
