Chvostek’s sign and Trousseau’s sign are clinical indicators of:

RML 2023

Medical & Surgical Nursing

Easy

Appeared in: RML 2023

Explanation

Hypocalcemia (low serum calcium) leads to increased neuromuscular excitability, a condition known as tetany.
Chvostek's sign (facial muscle twitching when the facial nerve is tapped) is a direct result of this nerve hyperexcitability.
Trousseau's sign (carpal spasm with cuff inflation) is also a classic manifestation of tetany caused by nerve ischemia and hyperexcitability.
The combination of both signs is a hallmark diagnostic clue for hypocalcemia.

Option A: Hyperkalemia (high potassium) primarily affects cardiac muscle and electrical conduction, leading to ECG changes (peaked T waves) and muscle weakness, not the specific tetany of Chvostek's and Trousseau's signs.
Option C: Hyponatremia (low sodium) primarily affects the central nervous system by causing cerebral edema. This leads to symptoms like confusion, headache, lethargy, and seizures, not peripheral neuromuscular signs like tetany.
Option D: While severe hypomagnesemia can also cause tetany and positive Chvostek's and Trousseau's signs, the combination of both is most classically and directly attributed to hypocalcemia. Often, hypomagnesemia leads to hypocalcemia, so the signs appear, but hypocalcemia is the more direct cause.

Clinical Relevance

Nursing practice connection: Knowing Clinical signs of hypocalcemia helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Recognizing Chvostek's and Trousseau's signs is a critical nursing assessment skill. A positive finding must be reported to the provider immediately as it indicates significant hypocalcemia.
Symptomatic hypocalcemia is a medical emergency due to the risk of life-threatening complications such as seizures, laryngospasm (which can obstruct the airway), and cardiac dysrhythmias.
Nurses should be especially vigilant for these signs in post-operative patients who have had thyroid or parathyroid surgery, as these glands are crucial for calcium regulation.

How to Approach the Question

First, identify the key terms in the question: 'Chvostek’s sign' and 'Trousseau’s sign'. Recognize these as specific clinical assessment findings.
Recall or deduce the pathophysiology associated with these signs. Both relate to increased neuromuscular excitability or 'tetany'.
Consider the options, which are all electrolyte imbalances. Evaluate how each imbalance affects neuromuscular function.
Eliminate options that cause different primary symptoms. Hyperkalemia affects the heart and causes weakness. Hyponatremia affects the brain (cerebral edema).
Differentiate between the remaining options. Both hypocalcemia and hypomagnesemia can cause tetany. However, the combination of Chvostek's and Trousseau's signs is the classic, hallmark presentation of hypocalcemia.
Select hypocalcemia as the most direct and common cause of these specific signs.

Concept Tested & Keywords

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