Respiratory: Laryngomalacia & Inhaled Foreign Body

Question 1

What is the most common congenital ariway disorder?

Answer 1

Laryngomalacia

Question 2

What is the most common cause of stridor in neonates?

Answer 2

Laryngomalacia

Question 3

What is laryngomalacia?

Answer 3

Characterised by flaccidity of the supraglotic structures.

The larynx is soft and floppy as a result and collapses during breathing.

Question 4

When does laryngomalacia typically present?

Answer 4

Within the first few weeks of life.

Typically resolves within the first two years, although in rare cases it can extend later into childhood.

Question 5

Why do symptoms in laryngomalacia typically peak at 6-8 months?

Answer 5

This is when respiratory function increases before the larynx (and hence diameter for airflow) increases in size.

Question 6

What causes inspiratory stridor in laryngomalacia?

Answer 6

Immature laryngeal cartilages collapse over the inlet to the larynx causing inspiratory stridor.

In particular these cartilages are:

• A long, curled, ‘omega-shaped’ epiglottis
• Tall, bulky aryepiglottic folds

Question 7

Clinical features of laryngomalacia?

Answer 7

1) Inspiratory stridor: worse on lying flat or exertion

2) Respiratory distress, failure to thrive and cyanosis are rare

3) Symptoms often mild with stridor being intermittent and not accompanied with other symptoms and no impact on growth.

Question 8

What are some signs of more severe causes of laryngomalacia?

Answer 8

• Respiratory distress
• Dyspnoea with intercostal / sternal recession
• Feeding difficulties or episodes of suffocation/cyanosis whilst feeding
• Poor weight gain
• Obstructive sleep apnoea

Question 9

Give 5 differentials for laryngomalacia

Answer 9

1) Vocal Cord Paralysis

2) Subglottic stenosis

3) Tracheomalacia

4) Croup

5) Supraglottitis / Epiglottitis

Question 10

Cause of bilateral vs unilateral vocal cord paralysis?

Answer 10

Bilateral –> most commonly congenital

Unilateral –> most common following surgery, causing recurrent laryngeal nerve injury

Question 11

What is the key investigation for confirming laryngomalacia?

Answer 11

Flexible endoscopy (laryngoscopy) via the nose or mouth to view the larynx and laryngeal cartilages.

Question 12

Management of mild cases of laryngomalacia?

Answer 12

Most (~90%) of cases are mild and do not require treatment.

Parents should be reassured that the condition will resolve by 12-16 months but symptoms may peak at 6 months and may be exacerbated following RTIs.

Question 13

Prognosis of laryngomalacia?

Answer 13

Prognosis is generally good and 99% will self-resolve with time.

Question 14

What are the 4 most common congenital airway abnormalities?

Answer 14

1) laryngomalacia
2) bilateral vocal cord paralysis
3) subglottic stenosis
4) laryngeal webs

Question 15

Give 3 differentials for a stridor in children

Answer 15

1) Croup

2) Epiglottitis

3) Laryngomalacia

Question 16

Give 4 differentials for a cough in children

Answer 16

1) CF
2) LRTI / pneumonia
3) TB
4) Pertussis (whooping cough)

Question 17

What are the most common objects that are inhaled (and cause problems)?

Answer 17

1) Food particles e.g. nuts, seeds
2) Toys e.g. beads
3) Small household items
4) Organic materials e.g. teeth

Question 18

Is the right or left bronchus more frequently involved in inhaled foreign bodies?

Answer 18

Right (due to its more vertical orientation)

Question 19

What is the classic triad of features with an inhaled foreign body?

Answer 19

1) Coughing paroxysms
2) Wheezing
3) Decreased breath sounds

Question 20

Clinical features of inhaled foreign body?

Answer 20

• Sudden onset choking or gagging
• Coughing paroxysms
• Stridor (if located above vocal cords)
• Wheezing or asymmetric breath sounds
• Decreased air entry on auscultation
• Cyanosis or respiratory distress
• Tachypnoea and tachycardia

Question 21

what are some complications of an inhaled foreign body?

Answer 21

Mechanical obstructoin of airflow –> atelectasis distal to the obstruction site

Granulation tissue formation and potential infection.

Question 22

What is the preferred method for removal of the foreign body?

Answer 22

Bronchoscopy

Question 23

What imaging may be useful in identifying the foreign body?

Answer 23

CXR
CT scan

Question 24

How is a diagnosis of laryngomalacia made?

Answer 24

Laryngoscopy or bronchoscopy

Question 25

When does laryngomalacia typically resolve?

Answer 25

Around 12-18 months as laryngeal muscles strengthen