Where is Choanal atresia, a congenital anomaly, located at?

Appeared in: DSSSB 12 August 2024

Explanation

Choanal atresia is a congenital blockage of the posterior nasal apertures, known as the choanae.
The choanae are the passages that connect the back of the nasal cavity to the nasopharynx, the upper part of the throat behind the nose.
Therefore, the obstruction in choanal atresia is located at the nasopharynx.
The blockage can be composed of bone (90% of cases) or soft tissue (10% of cases) and can affect one or both nasal passages.

Option A: Atresia of the common bile duct is a different condition known as biliary atresia. It affects the liver and digestive system, not the respiratory tract.
Option B: The gallbladder is an organ that stores bile and is part of the biliary system. It is not a passage that can have atresia. Choanal atresia is an anomaly of the respiratory tract.
Option D: Atresia of the anal canal is a condition called imperforate anus or anal atresia. It is a congenital defect of the gastrointestinal tract.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Anatomical location of choanal atresia as background academic context rather than a clinical decision trigger.
Bilateral choanal atresia is a neonatal respiratory emergency because newborns are obligate nose breathers. Nurses must be able to recognize the signs of respiratory distress immediately after birth.
A key assessment finding is 'cyclic cyanosis': the infant becomes cyanotic (blue) at rest or during feeding and then 'pinks up' when crying, as crying forces mouth breathing.
Immediate nursing intervention involves establishing an oral airway (e.g., using an oral airway device or a modified feeding nipple) and notifying the medical team for definitive treatment.

How to Approach the Question

First, identify the key terms in the question: 'Choanal atresia' and 'located at'.
Break down the medical term 'Choanal atresia'. 'Atresia' means the absence or blockage of a natural opening or passage.
Focus on the anatomical root word 'Choanal', which refers to the choanae.
Recall or deduce that the choanae are the posterior apertures of the nasal cavity that open into the pharynx.
Connect the two parts: 'Choanal atresia' is a blockage of the passage between the nose and the pharynx.
Evaluate the options. The nasopharynx is the upper part of the pharynx located directly behind the nasal cavity, making it the correct location. The other options relate to the biliary and gastrointestinal systems and can be ruled out.

Concept Tested & Keywords

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

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