A client is scheduled for a subtotal Thyroidectomy. Iodine solution (Lugol solution, potassium iodide solution) is prescribed. A nurse prepares to administer the medication, knowing that the therapeutic effect of this medication is to.

1. A

   Replace thyroid hormone

2. B

   Increase thyroid hormone production

3. C

   Prevent the oxidation of iodide

4. D

   Decrease Vascular and size of thyroid gland

Appeared in: PGIMER Sangrur NO - 2023

Explanation

• Lugol's solution, a strong iodine preparation, is given for 10-14 days before thyroid surgery.
• Its primary therapeutic effect is to decrease the vascularity (blood flow) and overall size of the thyroid gland.
• This action makes the gland firmer and less friable, which significantly reduces the risk of hemorrhage during the surgical procedure.
• It also temporarily inhibits the release of thyroid hormones (T3 and T4), helping to stabilize the patient and prevent a thyrotoxic crisis (thyroid storm).

Why Other Options Were Wrong

• Option A: This describes hormone replacement therapy, which is used to treat hypothyroidism (an underactive thyroid), not hyperthyroidism.
• Option B: Increasing hormone production would worsen the patient's hyperthyroid state and increase the risk of complications like thyroid storm.
• Option C: This is the mechanism of action for thionamide drugs, such as methimazole and propylthiouracil (PTU), not iodine solution.

Related Visual

Clinical Relevance

• Nursing practice connection: Knowing Preoperative pharmacological management for thyroidectomy helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
• Proper administration of pre-operative iodine solution is a critical nursing role to ensure surgical readiness and prevent intraoperative hemorrhage.
• Nurses must educate the patient on how to take the medication (diluted, with a straw) to improve tolerance and prevent side effects like teeth staining.
• Monitoring for signs of iodism (iodine toxicity), such as metallic taste, mouth sores, or gastric distress, is essential. If these occur, the nurse must withhold the dose and notify the provider.

How to Approach the Question

• First, identify the key components of the question: the procedure is a thyroidectomy, the drug is an iodine solution (Lugol's), and the question asks for its therapeutic effect in this specific pre-operative context.
• Recall the specific pharmacological action of high-dose iodine on the thyroid gland, which is different from its nutritional role.
• Analyze Option A: 'Replace thyroid hormone' is for hypothyroidism. The patient is having surgery for hyperthyroidism. Eliminate this option.
• Analyze Option B: 'Increase thyroid hormone production' would worsen the patient's condition. This is incorrect. High doses of iodine are inhibitory. Eliminate this option.
• Analyze Option C: 'Prevent the oxidation of iodide' describes the mechanism of a different class of antithyroid drugs (thionamides like PTU). This is a distractor. Eliminate this option.
• Analyze Option D: 'Decrease Vascular and size of thyroid gland' directly addresses the primary reason for giving iodine before thyroid surgery—to reduce bleeding risk and make the gland easier to remove. This aligns with known pre-operative protocols.

Concept Tested & Keywords

• Concept Tested: Preoperative pharmacological management for thyroidectomy
• Stem keywords: subtotal Thyroidectomy, Iodine solution, Lugol solution, potassium iodide solution, therapeutic effect
• Lead-in keywords: therapeutic effect
• Negative lead-in flag: false

Question ID

QNMPLv8Bi6UDbgvrw6uWG7

Copy ID

Reference Book

E6 Pharmacology KD Tripathi Essentials 9e Part 1 p. 306-308

E6 Medicine Davidson Principles Practice 24e p. 665-667

E6 Nursing Brunner Adult Health 3SA Vol 1 Part 4 p. 21-23