A drug used in a patient with shock?

Appeared in: VSSC Nursing Officer - 2021

Explanation

Dopamine is a vasoactive adrenergic drug indicated for the treatment of shock and hypotension.
It is a catecholamine that increases cardiac output and blood pressure.
Its effects are dose-dependent: low doses affect dopaminergic receptors (renal vasodilation), medium doses affect beta-1 receptors (increased contractility), and high doses affect alpha-1 receptors (vasoconstriction).

Option A: Nifedipine is a calcium channel blocker that causes vasodilation and lowers blood pressure, which would worsen the hypotension in a patient with shock.
Option B: Metoprolol is a beta-blocker that decreases heart rate and cardiac contractility. This would further reduce cardiac output and blood pressure, making it dangerous for a patient in shock.
Option C: Isoniazid is an antibiotic used specifically for the treatment of tuberculosis. It has no cardiovascular effects and is irrelevant to the management of shock.

Clinical Relevance

Nursing practice connection: Prioritize focused assessment, early escalation, and real-time monitoring when managing Pharmacological Management of Shock in acute care settings.
Administering vasopressors like dopamine is a critical nursing skill in intensive care.
Nurses must use an infusion pump for precise titration, preferably through a central line to prevent tissue damage (extravasation) from peripheral administration.
Continuous monitoring is essential, including heart rate, blood pressure (often via an arterial line), ECG, and urine output, to assess the drug's effectiveness and titrate the dose according to protocol to maintain a target Mean Arterial Pressure (MAP), typically greater than 65 mmHg.

How to Approach the Question

First, identify the core of the question. It asks for a drug used to treat 'shock'.
Recall the pathophysiology of shock: it's a state of inadequate tissue perfusion, most often characterized by severe hypotension (low blood pressure).
Therefore, the correct drug must be one that raises blood pressure and/or improves cardiac function.
Evaluate each option based on its primary mechanism of action:
Nifedipine: Lowers BP. Incorrect.
Metoprolol: Lowers heart rate and contractility. Incorrect.

Concept Tested & Keywords

Qh0uRM3zIpjfNI1NcyD7Js

E6 Pharmacology Nursing Lilley 11e Part 1 pp. 318-320, 317-319

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 690-692

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Attempt every question from this paper in a timed mock, then review the full solution for each one.