Which vitamin is essential for blood clotting?

Bihar CHO - 2021

Applied Nutrition & Dietetics

Easy

Appeared in: Bihar CHO - 2021

Explanation

Vitamin K is a fat-soluble vitamin essential for the synthesis of blood clotting factors in the liver.
It functions as a coenzyme for the gamma-carboxylation of precursor proteins for factors II (prothrombin), VII, IX, and X.
This carboxylation step is critical as it allows the clotting factors to bind calcium ions, thereby activating them to participate in the coagulation cascade.
Its name, Vitamin K, originates from the German word 'Koagulation' (coagulation).

Option A: Vitamin A is primarily involved in vision, immune function, cell growth, and maintaining epithelial tissue. It does not have a direct role in the synthesis of blood clotting factors.
Option C: Vitamin C (ascorbic acid) is vital for collagen synthesis, wound healing, and acting as an antioxidant. While severe deficiency (scurvy) can lead to bleeding due to weakened capillary walls, it does not affect the enzymatic pathway of blood coagulation.
Option D: Vitamin B refers to a complex of several different vitamins (B1, B2, B3, B6, B12, etc.) that are mainly involved in energy metabolism, DNA synthesis, and neurological function. They are not directly involved in the production of clotting factors.

Clinical Relevance

Nursing practice connection: Knowing Role of vitamins in blood coagulation helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Nurses administer a prophylactic intramuscular injection of Vitamin K to all newborns to prevent Vitamin K Deficiency Bleeding (VKDB), a potentially life-threatening condition.
When caring for patients on Warfarin (a Vitamin K antagonist), nurses must monitor the INR closely and provide patient education on maintaining a consistent dietary intake of Vitamin K to avoid sub-therapeutic or supra-therapeutic levels.
What if? A patient with end-stage liver failure is actively bleeding. The cause is the liver's inability to synthesize clotting factors, not a dietary deficiency of Vitamin K. In this scenario, administering Vitamin K would be ineffective; the correct intervention is to transfuse Fresh Frozen Plasma (FFP), which contains the pre-formed clotting factors.

How to Approach the Question

This is a factual recall question that tests your knowledge of the specific functions of different vitamins.
First, identify the key physiological process mentioned in the question stem: 'blood clotting'.
Next, systematically review the primary functions of each vitamin listed in the options.
Recall that Vitamin A is for vision, Vitamin C is for collagen and immunity, and the Vitamin B complex is for energy metabolism.
This process of elimination strongly suggests Vitamin K is the correct answer.
Confirm this by recalling that Vitamin K's name comes from the German word for coagulation ('Koagulation') and that it is essential for synthesizing clotting factors II, VII, IX, and X.

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