Which of the following is a cause of altered mental status?

• A. TBI
• B. Hypoxemia
• C. Shock
• D. TBI, Hypoxemia, and Shock

Answer: (D)

Altered mental status in a trauma patient often results from problems that impair brain function or its oxygen supply. The three most common contributors are traumatic brain injury, hypoxemia, and shock. Traumatic brain injury directly damages brain tissue and disrupts neuronal signaling, producing confusion, agitation, or unconsciousness. Hypoxemia lowers the oxygen carried to the brain; since the brain is highly sensitive to oxygen deprivation, even brief drops can quickly cause AMS. Shock causes insufficient blood flow and perfusion, including to the brain, leading to reduced cerebral oxygen delivery and impaired mental status. In many cases, more than one of these factors is present, so recognizing that all three can cause AMS guides rapid, targeted treatment—secure the airway and provide adequate oxygen, and address circulation to restore cerebral perfusion.