Vasopressors are medications that are used to:

RIMS Nursing Officer - 2022

Pharmacology

Easy

Appeared in: RIMS Nursing Officer - 2022

Explanation

Vasopressors are drugs that cause vasoconstriction, which directly increases Systemic Vascular Resistance (SVR).
Many vasopressors, like norepinephrine and epinephrine, also have positive inotropic effects (beta-1 stimulation), which increase cardiac contractility and, consequently, Cardiac Output (CO).
The combined effect of increasing both SVR and CO leads to a rise in Mean Arterial Pressure (MAP), which is the primary goal for improving organ perfusion in shock states.
Norepinephrine, the first-choice vasopressor in septic shock, has potent alpha-adrenergic effects (increasing SVR) and modest beta-adrenergic effects that help maintain or increase CO.

Option A: This describes the action of vasodilators or drugs used to treat hypertension, which is the opposite effect of vasopressors.
Option C: The primary purpose and direct effect of a vasopressor is to increase, not decrease, the Mean Arterial Pressure (MAP).
Option D: The therapeutic goal of using vasopressors is to restore and improve blood flow (perfusion) to vital organs by raising a critically low blood pressure.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacology and Hemodynamic Effects of Vasopressors as background academic context rather than a clinical decision trigger.
In clinical practice, vasopressors are critical in managing distributive, cardiogenic, and hypovolemic shock after adequate fluid resuscitation.
Nurses must titrate vasopressors to a specific MAP target (usually greater than 65 mmHg) while continuously monitoring for signs of effectiveness (e.g., improved urine output, mental status) and adverse effects (e.g., tachycardia, arrhythmias, peripheral ischemia).
Vasopressor extravasation (leakage into surrounding tissue) is a medical emergency that can cause severe tissue necrosis. It is crucial to administer these drugs through a central line whenever possible and to know the protocol for managing extravasation, which includes stopping the infusion and administering an antidote like phentolamine.

How to Approach the Question

First, identify the core term in the question: 'Vasopressors'.
Recall the basic definition and mechanism of this drug class. The prefix 'vaso-' refers to blood vessels, and 'pressor' means to press or constrict.
Therefore, the primary action is vasoconstriction, which increases the pressure against which the heart pumps. This pressure is known as Systemic Vascular Resistance (SVR).
Consider the effect on the heart. Many common vasopressors also stimulate the heart to pump harder, which increases Cardiac Output (CO).
Evaluate the options based on these two main effects: increased SVR and often increased CO.
Eliminate options that state the opposite (decrease SVR, CO, MAP) or describe an adverse outcome rather than the therapeutic goal (decrease perfusion).

Concept Tested & Keywords

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