Name two common secondary insults after TBI that worsen outcomes.

• A. Hypoglycemia and infection.
• B. Hypoxia and hypotension.
• C. Hyperthermia and hyponatremia.
• D. Seizures and anemia.

Answer: (B)

The main idea is that after a traumatic brain injury, the brain is especially vulnerable to secondary insults that cut off oxygen delivery or brain perfusion. The two most impactful and commonly seen are hypoxia and hypotension. When oxygen levels fall, brain cells can’t produce enough energy, leading to failure of ion pumps, calcium overload, excitotoxic injury, and expansion of the damage. Low blood pressure lowers cerebral perfusion pressure (especially if intracranial pressure is high), which reduces cerebral blood flow and starves brain tissue of oxygen and nutrients. This combination accelerates neuronal death, increases edema, and worsens functional outcomes.

In practice, preventing these insults is essential: ensure adequate airway and oxygenation to keep oxygen saturation high, and maintain blood pressure to sustain sufficient cerebral perfusion. Other factors like fever, hyponatremia, seizures, anemia, or infection can worsen outcomes as well, but hypoxia and hypotension are the most consistently identified two that drive the worst prognosis when they occur after TBI.