Croup Overview and Practice Questions Illustration

Croup: Overview and Practice Questions (2023)

by | Updated: Nov 8, 2023

Croup, predominantly seen in children, is a respiratory condition that often sends parents rushing to the doctor in the middle of the night.

Characterized by its telltale “barking” cough and a raspy voice, this inflammatory condition that affects the windpipe and voice box is primarily due to viral infections.

Understanding the causes, symptoms, and appropriate treatments for croup is crucial for medical professionals to ensure prompt and high-quality care.

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What is Croup?

Croup is a respiratory condition primarily affecting young children, characterized by a distinctive barking cough and stridor, a high-pitched noise when breathing in. It results from inflammation and narrowing of the airway below the vocal cords, typically due to viral infections. Early recognition and management can reduce complications.

Child with Croup Vector


Croup is predominantly caused by viral infections, with the parainfluenza virus being the most common culprit. Other viruses, such as adenovirus, respiratory syncytial virus (RSV), and measles, can also lead to croup.

While bacterial infections are less common causes, they can occasionally result in a more severe form known as bacterial tracheitis.

Environmental factors, like exposure to allergens or irritants, can exacerbate the symptoms, although they’re not primary causes.

Typically, a child with croup has been exposed to the virus a few days before the onset of symptoms, making early detection and isolation crucial in preventing its spread.

Signs and Symptoms

Croup is distinct in its presentation, especially in children. Recognizing the signs and symptoms early can aid in effective management.

Here are the predominant signs and symptoms of croup:

  • Barking Cough: The most characteristic symptom of croup is a cough that sounds like a seal’s bark. It often worsens at night.
  • Stridor: This is a high-pitched, wheezing sound that’s most noticeable when the child breathes in. It results from the narrowing of the airway below the vocal cords.
  • Hoarse Voice: The voice becomes raspy or muffled due to inflammation of the voice box.
  • Difficulty Breathing: Some children may show signs of labored breathing. The skin between the ribs or at the base of the neck might pull in with each breath—a sign of increased breathing effort.
  • Fever: A low-grade fever is sometimes present.
  • Restlessness or Irritability: Especially during the night when symptoms often exacerbate.
  • Red or Watery Eyes: Due to the strain of coughing or a concurrent viral infection.

Note: It’s crucial to monitor the severity of these symptoms. While mild cases of croup can be managed at home, more severe symptoms, such as pronounced difficulty breathing, bluish discoloration of the lips or face, or extreme lethargy, warrant immediate medical attention.


Treatment for croup aims to alleviate symptoms and ensure the child can breathe easily. The vast majority of cases of croup can be treated at home with simple measures, such as:

  • Humidifiers or steam inhalation
  • Cool-mist vaporizers
  • Oral fluids
  • Over-the-counter pain relievers

In severe cases, hospitalization may be necessary for observation and other treatment methods, including:

  • Intravenous fluids
  • Oxygen therapy
  • Aerosol medications
  • Corticosteroids

Note: Intubation and mechanical ventilation may be indicated for severe upper airway obstruction that puts the child at risk of respiratory failure. This requires inserting a breathing tube through the nose or mouth and connecting it to a machine for ventilatory support.

Croup Practice Questions

1. What is croup characterized by?
Croup is characterized by hoarseness, a resonant cough described as “barking” or “brassy,” varying degrees of inspiratory stridor, and varying degrees of respiratory distress resulting from swelling or obstruction in the region of the larynx and subglottic airway.

2. What is another name for croup?

3. What are the therapeutic management strategies for laryngotracheobronchitis?
The major objective of medical management is maintaining the airway and providing adequate respiratory exchange. The application of humidity with cool mist provides some relief in mild cases. Severe cases require the use of nebulized epinephrine. Oral steroids are an effective treatment of croup. Intubation and mechanical ventilation may be required during cases of severe airway obstruction.

4. What is the most common cause of stridor?

5. What is a common cause of stridor but is more severe than croup?

6. What are the signs and symptoms of croup?
Barking cough, hoarse voice, inspiratory stridor, difficulty breathing, and retractions.

7. What is the most common cause of croup?

8. What is the sign of croup on an x-ray?
Steeple sign

9. What is the most common age for getting croup?
6 months to 1.5 years (and a maximum of 36 months)

10. Where does croup start?
It often starts in the upper respiratory tract and progresses to the larynx and trachea.

11. What is stridor?
Stridor is a high-pitched, wheezing sound caused by disrupted airflow, often indicating an obstruction in the upper airway.

12. What are the clinical manifestations of croup?
Clinical manifestations of croup typically include a distinctive barking cough, hoarseness, stridor (a high-pitched wheezing sound, particularly noticeable when inhaling), and varying degrees of respiratory distress. These symptoms are often more pronounced at night and can be accompanied by a low-grade fever.

13. What is the primary clinical diagnosis of croup?
An x-ray that shows subglottic narrowing and an airway that appears as a steeple.

14. What are the medications for croup?
The primary medications for croup include: Oral corticosteroids (like dexamethasone) to reduce airway inflammation and swelling. Nebulized epinephrine for severe cases, offering quick relief from airway swelling in emergency situations.

15. Why is croup more common in infants than children?
Croup is more common in infants and toddlers due to their smaller airways. The inflammation and swelling associated with croup have a more significant impact on the narrower airways of young children, leading to the characteristic symptoms like stridor and the barking cough. As children grow and their airways enlarge, the same degree of swelling is less likely to cause severe symptoms.

16. How is croup described?
Croup is described as a respiratory condition primarily affecting young children, characterized by a distinctive barking cough, hoarseness, stridor, and difficulty breathing, often resulting from viral infection and inflammation of the larynx, trachea, and bronchi.

17. What is often seen in croup?
Narrowing and edema in the airway below the glottis. 

18. What is the most common type of croup?
Acute laryngotracheobronchitis

19. What age does acute laryngotracheobronchitis affect children?
Children less than 5 years old

20. What are the causes of acute laryngotracheobronchitis?
RSV, influenza type A and B, parainfluenza types 2 and 3, measles, and mycoplasma pneumoniae.

21. How is the onset of acute laryngotracheobronchitis?
Gradual onset with low-grade fever

22. What happens to the airways in acute laryngotracheobronchitis?
They become narrow, which makes it hard for the child to breathe.

23. What do infants and young children exhibit in acute laryngotracheobronchitis?
Intercostal retractions, nasal flaring, tachypnea, and stridor.

24. When does croup typically occur?
Most likely occur overnight from 10 pm to 4 am or early morning from 7-11 am.

25. What is the most common cause of croup?
Parainfluenza virus type 1

26. How does the virus infect the nasal and pharyngeal mucosal epithelium?
It spreads along the respiratory epithelium to the larynx and trachea.

27. What happens in severe cases of croup?
Mucosal edema, fibrinous exudates, and pseudomembranes can build up on the tracheal surface and further contribute to airway narrowing.

28. Does croup affect the subglottic or supraglottis region?

29. What are the clinical features of croup?
Gradual onset and initially present with URI symptoms (e.g., coryza, congestion).

30. How does croup progress over 12‐48 hours?
Fever, hoarseness, barking cough (expiratory), and stridor (inspiratory).

31. What are the factors associated with severe croup?
Sudden onset of symptoms, rapid progression (< 12 hours), previous episodes of croup, abnormality of the airway, and medical conditions that predispose respiratory failure (e.g., neuromuscular disorders, asthma, cystic fibrosis).

32. What is the hallmark chest x-ray finding with croup?
Steeple sign

33. What are the complications of croup?
Hypoxemia, respiratory failure, pulmonary edema, pneumothorax, secondary bacterial infection, tracheitis, bronchopneumonia, and pneumonia.

34. How does croup begin?
It begins as an upper respiratory infection with nasal congestion and coughing.

35. What area does croup affect, and how?
It affects the larynx and subglottic area, causing inflammation that leads to obstruction, swelling, and exudate.

36. What infection does croup lead to?

37. What is laryngotracheobronchitis?
Laryngotracheobronchitis is another name for croup.

38. What is a croup tent?
A croup tent is an outdated method that was used to provide a cool, moist environment for children with croup to alleviate symptoms. It was a clear plastic tent or hood placed around a child’s bed, often with cool mist directed into it.

39. What is the difference between croup and whooping cough?
Croup is caused by a viral infection leading to a barking cough and stridor due to swelling of the upper airway. Whooping cough, or pertussis, is a bacterial infection characterized by severe coughing fits followed by a high-pitched “whoop” sound during the intake of breath.

40. What does a croup cough sound like?
A croup cough is distinctive and sounds like a seal’s bark, often being described as “barking.” It’s typically louder and harsher than a regular cough.

41. What virus is most commonly associated with causing croup?
Parainfluenza virus

42. At what age range is croup most commonly seen?
Children between 6 months and 3 years of age are most commonly affected.

43. What is the hallmark symptom of croup?
A barking cough

44. How can you differentiate between croup and whooping cough?
Croup is characterized by a barking cough and stridor, while whooping cough, or pertussis, features severe coughing fits followed by a “whooping” sound during the intake of breath.

45. What type of medication is commonly used to treat croup?
Oral corticosteroids, like dexamethasone, are commonly used.

46. Can croup be treated at home, and if so, how?
Mild cases can often be managed at home with cool mist, hydration, and keeping the child calm.

47. What is stridor, and how is it related to croup?
Stridor is a high-pitched wheezing sound during inhalation, common in croup, indicating narrowed airways.

48. Why should aspirin be avoided in children with croup?
Aspirin is linked to the risk of Reye’s syndrome in children, especially during viral illnesses.

49. In which scenario should a parent seek immediate medical attention for a child with croup?
Seek immediate attention if the child has severe breathing difficulty, stridor at rest, blue lips, or is extremely lethargic.

50. Can adults get croup?
Although rare and typically milder due to larger airways, adults can get croup, with symptoms like a barking cough and hoarseness.

Final Thoughts

Croup is a prevalent pediatric respiratory ailment, distinguishable by its unique cough and stridor.

While most cases are mild and resolve without complications, timely identification and appropriate medical intervention are crucial, as severe cases can progress to life-threatening respiratory obstruction.

As with many illnesses, early detection and a basic understanding of the condition can equip caregivers and parents with the tools needed to ensure optimal outcomes for affected children.

Written by:

John Landry, BS, RRT

John Landry is a registered respiratory therapist from Memphis, TN, and has a bachelor's degree in kinesiology. He enjoys using evidence-based research to help others breathe easier and live a healthier life.


  • Rrt, Des Terry Jardins MEd, and Burton George Md Facp Fccp Faarc. Clinical Manifestations and Assessment of Respiratory Disease. 8th ed., Mosby, 2019.
  • Faarc, Kacmarek Robert PhD Rrt, et al. Egan’s Fundamentals of Respiratory Care. 12th ed., Mosby, 2020.
  • Sizar O, Carr B. Croup. [Updated 2023 Jul 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023.

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