What is the precautionary step to be taken before administering an antiserum (or) antitoxin?

RRB Nsg. Superintendent-20 July 2019 (Shift-2)

Pharmacology

Easy

Appeared in: RRB Nsg. Superintendent-20 July 2019 (Shift-2)

Explanation

Antisera and antitoxins are biological products, often derived from animal sources, which contain foreign proteins.
These foreign proteins can trigger a severe, life-threatening Type I hypersensitivity reaction (anaphylaxis) or a delayed Type III reaction (serum sickness).
A sensitivity test is performed to screen for this hypersensitivity by exposing the patient to a very small, controlled amount of the substance before administering the full therapeutic dose.
The test involves an intradermal injection of a diluted solution, and a positive result (wheal and flare) indicates a high risk of a systemic reaction.
This precaution is a critical patient safety measure to prevent anaphylactic shock.

Option A: A urine test assesses renal function, hydration status, and detects metabolic or urinary tract diseases. It does not provide any information about a patient's potential allergic response to foreign proteins.
Option B: While a blood test can measure total or specific IgE antibodies to assess for allergies, it is not the standard procedure for immediate, pre-administration screening for a specific antiserum. The results are not available quickly enough, and the skin test is a more direct and rapid assessment of immediate hypersensitivity.
Option C: A Cerebrospinal Fluid (CSF) test is a diagnostic procedure to analyze the fluid surrounding the brain and spinal cord. It is used to detect infections (like meningitis), bleeding, or neurological disorders. It has no role in allergy testing.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Precautionary measures before administering antiserum or antitoxin as background academic context rather than a clinical decision trigger.
A nurse's primary role during antiserum administration is patient safety. This includes correctly performing the sensitivity test, interpreting the results, and being prepared for an emergency.
Always have an anaphylaxis kit, including pre-drawn epinephrine (adrenaline), at the bedside before starting the sensitivity test or administering the serum. Seconds count in an anaphylactic reaction.
What if the sensitivity test is positive, but the antitoxin is life-saving (e.g., for a venomous snakebite)? The decision to proceed rests with the physician. The nurse must be prepared to assist with a rapid desensitization protocol and manage a potential severe reaction, often in an ICU setting.

How to Approach the Question

First, identify the core subject of the question: administering 'antiserum' or 'antitoxin'.
Recall the nature of these substances. They are biological agents, often made from non-human (animal) sources.
This should immediately trigger the concept of 'foreign proteins' and the associated risk of 'allergic reactions' or 'hypersensitivity'.
Evaluate the options based on this risk. Which test is designed to detect an immediate allergic sensitivity to a specific substance?
Eliminate the tests that are irrelevant to allergy detection: Urine test (kidneys), CSF test (central nervous system), and Blood test (not the primary, immediate screening tool).
Conclude that the 'Sensitivity test' is the only option that directly addresses the primary risk associated with administering foreign serum.

Concept Tested & Keywords

Concept Tested: Precautionary measures before administering antiserum or antitoxin.
Stem keywords: precautionary step, antiserum, antitoxin
Lead-in keywords: What is
Negative lead-in flag: false

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