Effect of vasodilator includes, except?

AIIMS Rishikesh & Jodhpur NO - 2017

Pharmacology

Medium

Appeared in: AIIMS Rishikesh & Jodhpur NO - 2017

Explanation

Vasodilators are medications that open (dilate) blood vessels, which decreases systemic vascular resistance.
This mechanism of action directly leads to a fall in blood pressure, an effect known as hypotension.
Hypertension, or high blood pressure, is a primary indication for prescribing vasodilator drugs. Therefore, it is the condition they treat, not an effect they cause.

Option A: This is incorrect because hypotension (low blood pressure) is the primary and expected therapeutic effect of a vasodilator.
Option C: This is incorrect because diuresis (increased urine output) can be an indirect effect of some vasodilators, especially when used in heart failure, as they can improve cardiac output and thus enhance blood flow to the kidneys.
Option D: This is incorrect because sweating is a documented side effect of certain vasodilators, such as hydralazine. It is often associated with flushing or the body's reflex response to a drop in blood pressure.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacological effects of vasodilators as background academic context rather than a clinical decision trigger.
A key nursing responsibility is to monitor the patient's blood pressure closely after administering a vasodilator to prevent and manage symptomatic hypotension.
Patient education should include instructing patients to report signs of hypotension like dizziness, lightheadedness, or fainting, and to change positions slowly (e.g., from lying down to sitting up).
What if? If the patient is also taking another antihypertensive, such as a diuretic, the risk of severe hypotension is significantly increased. This requires more frequent blood pressure monitoring and potential dose adjustments.

How to Approach the Question

First, analyze the core term in the question: 'vasodilator'. Break it down: 'vaso' refers to blood vessels, and 'dilator' means to widen or expand.
Next, identify the negative framing of the question by spotting the keyword 'except'. This means you are looking for the one option that is NOT an effect of vasodilators.
Logically deduce the primary effect: if a blood vessel widens, the pressure of the fluid (blood) inside it will decrease. This leads to hypotension (low blood pressure).
Evaluate each option based on this understanding. Hypotension is a direct effect. Hypertension (high blood pressure) is the opposite of this effect.
Consider the other options. Sweating and diuresis are known potential side effects or indirect effects of these medications.
Conclude that hypertension is the only option that is fundamentally contrary to the action of a vasodilator.

Concept Tested & Keywords

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