During secondary assessment of hypothermia, ABG may show which finding?

• A. Normal ABG
• B. Moderate to severe acidosis with hypoxemia
• C. Alkalosis with hypoxemia
• D. Hypercapnia only

Answer: (B)

In hypothermia, reduced tissue perfusion and often impaired oxygen delivery push cells into anaerobic metabolism, causing lactic acid buildup and metabolic acidosis. At the same time, overall oxygenation can be compromised, so arterial oxygen tension falls, producing hypoxemia. So the common ABG pattern is moderate to severe acidosis with hypoxemia.

The other patterns don’t fit as well: a normal ABG would miss the significant derangements expected with hypoperfusion and lactic acidosis; an alkalosis would suggest net loss of acid or excess base not typical in hypothermia; and a sole hypercapnia implies a primary respiratory issue without the accompanying hypoxemia and metabolic acidosis usually seen in this scenario.