Wilderness and Rescue Medicine 8th Edition

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Wilderness and Rescue Medicine

Chapter 6 Review: The Nervous System

• Brain failure can lead to loss of nervous system control over other critical systems. Possible causes are summarized by the mnemonic STOPEATS. • Subtle changes in mental status are often the earliest indicators of a problem with brain perfusion and oxygenation and may indicate progression toward brain failure. • Traumatic brain injury (TBI) is a common cause of temporary brain failure and carries the antici- pated problem of increased intracranial pressure (ICP). Other causes of increased ICP include stroke, electrical injury, hyperthermia, and hypoxia. • Increasing ICP produces a pattern of symptoms beginning with persistent vomiting, severe headache, and mental status changes. Late signs include seizure, unequal pupils, and posturing. • The treatment for increased ICP includes urgent evacuation to neurosurgical care, airway protection, ventilation as needed, and maintaining body core temperature. • Seizure is an emergency when it is caused by ICP or an undiagnosed problem. It is less of an emer- gency in a patient with a history of epilepsy who recovers to normal mental status following seizure. • Exercise-associated hyponatremia is usually due to low blood salts from too much water intake and it is most common with extreme athletes. • The signs and symptoms of hyponatremia include altered mental status, slow mentation, seizures, and nausea. • Hyponatremia patients who do not begin to improve quickly with water restriction and salt intake should be evacuated to definitive care. • Hydration should be initiated for hyponatremia only if signs and symptoms of dehydration are also present and blood electrolytes can be measured. • Any condition of persistent altered mental status that cannot be corrected is an emergency.