Which of the following is a component of the lethal diamond?

• A. Hypocalcemia
• B. Hypokalemia
• C. Hypoxia
• D. Hypernatremia

Answer: (A)

The lethal diamond represents a set of critical derangements that drive mortality in severe hemorrhagic shock. Calcium is essential for both the coagulation cascade and cardiovascular function. When calcium levels fall, clotting becomes impaired and the heart and vessels don’t contract and respond as well, making resuscitation and bleeding control much harder. In practice, citrate used in stored blood can bind calcium, and tissue injury itself can lower ionized calcium, so hypocalcemia directly worsens coagulopathy and hemodynamics. That’s why it’s identified as a component of the lethal diamond.

Hypokalemia isn’t a defining factor of this framework, and hypoxia and hypernatremia are not the characteristic components emphasized in this context.