What is choanal atresia?

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

Explanation

Choanal atresia is a congenital condition where a bony or membranous septum blocks the posterior nasal passage (choana).
This obstruction prevents the normal flow of air from the nasal cavity into the nasopharynx.
The term 'choana' refers to the posterior nasal apertures, and 'atresia' means the absence or abnormal narrowing of a body opening.
Therefore, the definition directly corresponds to a congenital obstruction involving the nasopharynx.

Option B: This is incorrect. An obstruction of the middle ear would affect hearing and balance and involves structures like the Eustachian tube or ossicles, not the nasal airway.
Option C: This is incorrect. The urethra is part of the urinary system. An obstruction here, such as posterior urethral valves, affects urination and is unrelated to the respiratory system.
Option D: This is incorrect. The oropharynx is the part of the throat located behind the mouth. Choanal atresia is an obstruction at the junction of the nasal cavity and the nasopharynx, which is superior to the oropharynx.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Congenital anomalies of the upper respiratory tract as background academic context rather than a clinical decision trigger.
Bilateral choanal atresia is a neonatal emergency presenting with 'cyclic cyanosis'—the infant becomes cyanotic during quiet breathing or feeding and pinks up when crying (as this forces mouth breathing).
Immediate nursing action for a suspected bilateral atresia is to establish an oral airway to bypass the nasal obstruction until surgical correction can be performed.
A simple bedside diagnostic test is the inability to pass a small-caliber catheter through each nostril into the oropharynx.

How to Approach the Question

First, identify the key medical term in the question: 'choanal atresia'.
Break down the term into its components. 'Choana' refers to the posterior openings of the nasal cavity. 'Atresia' means the absence or abnormal closure of a body orifice or passage.
Combine the meanings: Choanal atresia is the closure of the posterior nasal passages.
Consider the anatomy. The posterior nasal passages open into the nasopharynx (the upper part of the throat, behind the nose).
Evaluate the options based on this anatomical understanding. An obstruction between the nose and the pharynx is an obstruction of the nasopharynx.
Eliminate the other options as they refer to anatomically incorrect locations: the middle ear (hearing), the urethra (urinary system), and the oropharynx (behind the mouth).

Concept Tested & Keywords

Q6BoTnc9uHkOkPTn7WBik8

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 330-332

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

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