Typical finding in anaphylactic shock?

Appeared in: KPSC Staff Nurse - 2015

Explanation

Wheezing is a classic respiratory sign of anaphylaxis caused by bronchoconstriction (narrowing of the airways) and airway edema.
This occurs due to the release of inflammatory mediators like histamine and leukotrienes from mast cells and basophils.
It is an audible, high-pitched whistling sound, primarily heard during expiration, indicating lower airway obstruction.

Option A: Anuria (absence of urine) is a sign of acute kidney injury due to prolonged and severe hypotension. It is a late complication of shock, not a typical initial finding.
Option B: Anaphylactic shock causes hypotension, which triggers a compensatory tachycardia (rapid heart rate), not bradycardia (slow heart rate).
Option D: Anaphylaxis is characterized by widespread vasodilation, which leads to severe hypotension (low blood pressure), the opposite of hypertension.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Clinical manifestations of anaphylactic shock as background academic context rather than a clinical decision trigger.
Prompt recognition of wheezing as a sign of anaphylaxis is a critical nursing skill that enables the immediate initiation of life-saving interventions, primarily the administration of epinephrine.
A delay in treatment can lead to complete airway obstruction, respiratory arrest, cardiovascular collapse, and death.
What if? If the patient presented with stridor (a high-pitched sound on inspiration) instead of or in addition to wheezing, it would indicate upper airway obstruction (laryngeal edema). This is an even more critical emergency, signaling impending airway closure and requiring immediate, aggressive airway management.

How to Approach the Question

First, identify the core concept of the question: the characteristic signs of anaphylactic shock.
Recall the basic pathophysiology of anaphylaxis, which involves a massive release of inflammatory mediators like histamine.
Consider the effects of these mediators on the body's systems. Histamine causes bronchoconstriction, vasodilation, and increased capillary permeability.
Evaluate each option based on this pathophysiology:
Bronchoconstriction directly leads to wheezing.
Vasodilation leads to hypotension, which the body compensates for with tachycardia, making bradycardia and hypertension incorrect.

Concept Tested & Keywords

Q1GXWAeSxQM3EZ6ckBDyCt

E6 Medicine Harrison 22e Part 2 p. 716-718

E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 1448-1450

E6 Pathology- ROBBINS & COTRAN PATHOLOGIC BASIS OF DISEASE 10TH Ed p. 215-217

Practise the full KPSC Staff Nurse - 2015

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