Atropine is commonly used prior to administration of inhalant anaesthetics to reduce

RUHS, Jaipur, M.Sc Nursing Entrance Exam-2024

Pharmacology

Easy

Appeared in: RUHS, Jaipur, M.Sc Nursing Entrance Exam-2024

Explanation

Atropine is an anticholinergic/antimuscarinic drug used as a preanesthetic medication.
Its primary function in this context is to block muscarinic receptors, which leads to a significant reduction in salivary and bronchial secretions.
This action is crucial for preventing airway complications like laryngospasm and obstruction, which can be stimulated by inhalant anesthetics.
By drying up secretions, atropine helps maintain a patent and clear airway during surgery.

Option A: Atropine does not act on nicotinic receptors at the neuromuscular junction and therefore has no effect on skeletal muscle tone.
Option C: Atropine is not a primary antiemetic and can sometimes cause nausea. Its effects are not targeted at the chemoreceptor trigger zone responsible for vomiting.
Option D: Atropine blocks the parasympathetic (vagal) influence on the heart's sinoatrial (SA) node, which leads to an increase in heart rate (tachycardia), not a reduction.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacology of Atropine as a Preanesthetic Medication as background academic context rather than a clinical decision trigger.
Understanding the pharmacology of preanesthetic medications like atropine is critical for patient safety. The primary nursing role is to administer the medication as ordered and monitor for both therapeutic effects (dry mouth) and adverse effects (excessive tachycardia, urinary retention).
Nurses must be aware that while reducing secretions is the goal, the resulting dry mouth can be very uncomfortable for the patient. Providing mouth care can increase patient comfort.
What if? If a patient has pre-existing tachycardia (a high heart rate) or is at risk for it (e.g., due to anxiety or fever), the anesthesiologist might choose glycopyrrolate instead of atropine. Glycopyrrolate has a similar antisecretory effect but causes less tachycardia because it does not cross the blood-brain barrier as readily.

How to Approach the Question

First, identify the core of the question: What is the primary reason for giving atropine before anesthesia?
Recall the drug class of atropine. It is a classic anticholinergic (antimuscarinic) agent.
Think about the main effects of anticholinergic drugs: "can't see, can't pee, can't spit, can't..." (a common mnemonic). The "can't spit" part refers to drying up secretions.
Evaluate each option based on atropine's known pharmacological effects.
Eliminate 'Muscle tone' as that involves neuromuscular blockers.
Eliminate 'Nausea and vomiting' as that involves antiemetics.

Concept Tested & Keywords

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