Hypoxic Ischemic Encephalopathy (Cerebral Hypoxia, HIE)

Drug overdose Drowning Lack of oxygen due to smoke inhalation Extremely low blood pressure Strangulation Injury or complication during birth Cardiac arrest Carbon monoxide poisoning High altitudes Choking Compression or injury to the trachea that reduces or stops breathing Complications from general anesthesia Diseases that cause paralysis of the respiratory organs or muscles (such as myasthenia gravis or Guillane-Barre syndrome) Risk Factors A risk factor is something that increases your chance of getting a disease or condition. Any injury, complication, or health condition that causes the brain to have a reduction in blood flow and oxygen deprivation is a risk factor for hypoxic ischemic encephalopathy. Symptoms Symptoms include: Mild case: Difficulty concentrating or paying attention Poor judgment Poor coordination Extreme Lethargy Severe oxygen deprivation: Coma No brain stem reflexes (eg, breathing and responding to light) Only blood pressure and heart function reflexes are functioning Diagnosis The doctor must work quickly to perform a physical exam.

Tests may include the following: CT scana scan that uses x-rays and computer software to make pictures of your brain MRI scana test that uses magnetic waves to make pictures of structures inside the brain Electrocardiogram (EKG, ECG)a test that records the hearts activity by measuring electrical currents through the heart muscle Echocardiograma test that uses high-frequency sound waves (ultrasound) to examine the size, shape, and motion of the heart Blood tests, including arterial blood gases and blood glucose levels Electroencephalogram (EEG)a test that records the brains activity by measuring electrical currents through the brain Evoked potentialsa test that shows whether or not the brain has an electrical response to sensations like sight and touch Treatment Treatment depends on the underlying cause of the condition, as well as the severity of the damage to the brain. Treatment options include: Life-Sustaining Treatment If brain function has stopped but damage is not yet extensive, life-sustaining treatment is administered. Mechanical Ventilation Mechanical ventilation may be needed to sustain breathing. Treatments for the Circulatory System Treatments are administered to maintain heart function and control blood pressure.

Seizure Control Medications and general anesthesia may be administered to control seizures. Cooling Blankets Hypoxic brain damage is often caused by heat, so cooling blankets or other means of cooling may be applied to reduce the body's temperature. Prevention Prevention is dependent upon the cause of the condition, but in most cases hypoxic ischemic encephalopathy is unexpected and cannot be prevented. To prevent significant or long-term brain damage once the oxygen supply has been reduced, CPR may be administered. RESOURCES: Brain Injury Association of America http://www.biausa.org/ National Institute of Neurological Disorders and Stroke http://www.ninds.nih.gov/ CANADIAN RESOURCES: Hotchkiss Brain Institute http://www.hbi.ucalgary.ca/ Ontario Brain Injury Association http://www.obia.on.ca/ References: Brain injury secondary to carotid intervention [review]. J Endovasc Ther. 2007 Apr;14:219-231. Harrington DJ, Redman CW, Mouldan M, Greenwood CE. The long-term outcome in surviving infants with Apgar zero at 10 minutes: a systematic review of the literature and hospital-based cohort [review]. Am J Obstet Gynecol. 2007;196:463.e1-5. Hypoxic ischemic encephalopathy (HIE). Neurographics website. Available at: http://www.neurographics.org/2/1/1/4.shtml.Accessed June 2, 2007.

Itoo BA, Al-Hawsawi ZM, Khan AH. Hypoxic ischemic encephalopathy. Incidence and risk factors in North Western Saudi Arabia. Saudi Medical Journal. 2003;24:147-153. Available at: http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=12682677&dopt=Abstract. Puohit, D and Silverstein, S. Perinatal hypoxic-ischemic encephalopathy. In: Gilman S, ed. MedLink Neurology. San Diego, CA: MedLink Corporation. Available at: http://www.medlink.com. Accessed August 10, 2007. Schulzke SM, Rao S, Patole SK. A systematic review of cooling for neuroprotection in neonates with hypoxic ischemic encephalopathy-are we there yet? BMC Pediatr. 2007;7:30. US National Library of Medicine website. Available at: http://www.nlm.nih.gov/medlineplus/ency/article/001435.htm. Last reviewed April 2008 by Rimas Lukas, MD Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.