Understanding severe croup: An overview

Croup defines a range of lung infections present in children. Rarely, croup can present as severe symptoms causing significant illness and requiring urgent, comprehensive treatment. Croup resolves completely after treatment, however, in some cases, complications can arise later in life impacting well-being. In this article, we shall discuss the complications of severe croup and how to avoid them.

What is croup?

Commonly seen in infants and young children, croup is a contagious condition that causes swelling in the respiratory system. Starting from the nose and throat, the swelling can progress to the upper part of our lungs. Usually caused by viruses, croup causes symptoms such as a characteristic barking cough and hoarseness of voice. These develop gradually, starting with a stuffy and runny nose with a mild fever and lasting about a week before it resolves. However, sometimes croup can become severe, causing significant swelling in the throat, windpipe and lungs, a high fever and difficulty in breathing.¹

What happens when croup becomes severe?

Severe croup is an emergency requiring urgent attention and treatment. The throat and the upper airways become swollen making it difficult to breathe in. This reduces the oxygen levels of the blood making it very frightening for the child and the caregivers.² While mild croup presents with a barking cough and noisy breathing, the child is generally alert. In moderate croup, the child has noisy high-pitched breathing, sucking in the skin around the ribs and sternum (called chest retractions) and may present as slightly disoriented.² A child with severe croup has all the symptoms of mild and moderate croup but presents as agitated yet tired. The chest retractions are visible and there may be a blue tinge to the skin (cyanosis) due to low oxygen levels.^1,2 Let us discuss the causes and symptoms below in further detail.

Causes and symptoms of severe croup

The parainfluenza virus most commonly causes severe croup. Other culprits may be the respiratory syncytial virus and the influenza virus. Rarely, croup could be bacterial, requiring a different approach to treatment. Highly contagious, croup can be spread by the air droplets expelled during sneezing and coughing from infected individuals.³

Warning symptoms of severe croup

• Barking cough: commonly described as resembling the sound of a seal or a barking dog, the child may have bouts of cough. This characteristic sound is due to the swelling of the voice box, which is present in the throat
• Stridor: this is a high-pitched wheezing sound that occurs while breathing in. In severe croup, this can be heard even when the child is resting.
• Retractions in the ribs: Due to the swollen airways, there is an increased effort in breathing by the muscles of the chest. This causes visible retractions or sucking in the skin between the ribs during breathing
• Cyanosis: A blue tinge may be seen on the child’s lips, nose, cheeks, fingers, nails, earlobes, inside of the cheek and in severe cases, other areas of the skin. This is due to a decrease in oxygen levels due to incomplete breathing
• Swollen lymph nodes and conjunctivitis: Sometimes, there may be redness in the eyes and swollen lymph nodes in the neck or underarms of the child. This depends on the virus that has caused the croup
• Behavioural changes: The child may be agitated, crying inconsolably, exhausted and frightened⁴

Croup is diagnosed based on these symptoms especially when they present during the colder parts of the year. Usually, scans and laboratory tests are not needed for diagnosis but may be done to monitor the general condition and functioning of the child.⁵ 

Management of severe croup

Severe croup is a life-threatening condition and requires urgent admission. Some supportive treatment may be started in the ambulance or the accident and emergency department itself.

Treatment depends on the symptoms and signs that the child presents with and the severity of the illness. Usually, it includes the following:

• Oxygen supplementation: this is done with a facemask or through the nostrils to increase oxygen levels in the blood.  This is done when the child shows signs of cyanosis (blue tinge to skin, nails, tongue, cheeks)⁶
• IV fluids: The medical team will place an intravenous (IV) cannula in the arm to ensure that fluids and medications are administered urgently to the child. Due to the fever, cough and breathing difficulties, the child may not be able to consume fluids and show signs of dehydration⁶
• Breathing tube: Rarely (<1%), children with severe croup need a tube placed through the mouth into the throat, a procedure called intubation. This is done when the swelling is extremely severe, especially in the throat and the child is unable to breathe, disoriented or unconscious⁶
• Medications: to reduce the swelling in the respiratory tract quickly, healthcare professionals have to administer medications such as epinephrine and dexamethasone. These medications rapidly reduce swelling in the tract and reduce the difficulty in breathing. Epinephrine is administered through a mist that is breathed in through the facemask or an injection in the muscle. Dexamethasone is administered through injection in the muscle or through the IV line⁶

Antibiotics, cough medicines, decongestants and sedatives are not preferred in children with croup. Antibiotics are ineffective against viruses so are not recommended. Cough medicines and decongestants can be counterproductive as they can mask the symptoms of difficulty in breathing and low oxygen levels leading to severe symptoms in the long run.⁷

Long-term consequences

Severe croup usually resolves completely with prompt treatment. However, depending on the severity of symptoms, the treatment pathway and the child’s response to the treatment, some long-term consequences can be expected, though rarely. The impact of croup can extend beyond the acute attack itself and show up differently at different points of the child’s life. Here we delve into the potential complications that a severe episode of croup can pose at various stages of a child’s life and into adulthood.

Childhood 

Persistent respiratory symptoms

• Symptoms such as wheezing, coughing and breathlessness during activity may recur even after the episode of severe croup has been resolved. This can have an impact on the normal activity levels of children⁸
• There are chances of recurrence of the croup episode as well, which must be attended to immediately⁸

Psychological impact

• The experience of the symptoms of croup and hospitalisation in the intensive care unit can be a traumatic experience for children and their families⁹
• Children may develop a fear of respiratory symptoms such as breathlessness, which can lead to avoidance of physical activities for the fear of having another episode⁹

Adolescence

Increased risk of Asthma

Children who have had an episode of severe croup may have a higher chance of developing asthma in childhood or adolescence. ¹⁰

Asthma is a respiratory illness characterised by breathing difficulties, wheezing, cough and rapid incomplete breathing patterns in response to certain triggers like exercise, allergens or psychosocial stress.¹⁰

Reduced lung function

Long-term follow-up studies of adolescents who have had croup in their childhood have reported reduced breathing capacity than their peers.

This could be found in a breathing test (spirometry) that measures the lung capacity of the individual.¹¹

Increased risk of respiratory infections

Adolescents with a history of croup may fall sick with breathing-related symptoms often.¹¹

They can also be more susceptible to more severe symptoms during common colds or the flu.¹¹

Adulthood

Increased risk of respiratory and heart problems

Asthma may increase the risk of developing lung abnormalities like chronic obstructive pulmonary disease in the future if adequate treatment is not maintained throughout life.¹²

Long-term respiratory conditions may also increase the risk of heart disease.¹²

Management and prevention of long-term effects

Follow-up care and monitoring

Children who have experienced an episode of severe croup are given a follow-up schedule to monitor progress and symptoms or new concerns.

The medical professional may prescribe tests to check the child’s lung function, called pulmonary function tests.

X rays or other imaging scans may be done if the doctor suspects changes to the structure of the lungs and checks the airways.¹³

Respiratory therapy

Children with persistent breathing symptoms may benefit from physiotherapy targeted towards breathing exercises.

Gradually improving physical activity levels in a controlled environment can improve the child’s relationship with exercise and deal with breathing changes.

Inhalers or corticosteroids may be prescribed after the episode to prevent the episode from occurring again.¹³

Psychological support

An episode of severe croup, the subsequent hospitalisation and the urgency of the situation can be traumatic to the child and the family members. ¹⁴

Understanding the disease, having a detailed discussion with the medical team, reading associated patient information material given by the hospital, counselling, support groups, and sometimes psychology referrals are beneficial in dealing with the event healthily.¹⁴

Healthy lifestyle choices

Encouraging a healthy and nutritious diet, lots of fluids and fresh produce is vital to ensure proper healing.

Taking prescribed medications on time and in the correct dosage as per the doctor’s instructions is important.¹³

If you have been prescribed glucocorticosteroids, there are specific instructions regarding when to take them and the dosage. You cannot stop these medications without the guidance of your doctor.¹⁵

FAQ’s

What are the complications of severe croup?

Complications of severe croup can include respiratory distress, cyanosis, and respiratory failure. In some cases, croup can lead to bacterial infection of the windpipe, pneumonia, or an ear infection.¹¹

What happens if croup does not get better?

If croup doesn't improve with treatment, it can lead to worsening respiratory distress and potentially life-threatening complications. In severe cases the windpipe and voice box get swollen and airway obstruction may occur, necessitating urgent medical intervention.¹¹

Can croup be permanent?

No, croup itself is not permanent. However, in some cases, children with severe or recurrent croup may develop long-term respiratory symptoms, such as wheezing or coughing, which may persist.⁸

Can croup damage the lungs?

Croup typically affects the upper airway and does not directly damage the lungs. However, severe cases of croup can cause inflammation and swelling in the airway, leading to respiratory distress. Prolonged or recurrent episodes of croup may increase the risk of developing asthma or other respiratory conditions later in life.^8,10

What is the longest croup can last?

The duration of croup can vary depending on the severity and underlying cause. Most cases of croup resolve within a few days, with symptoms improving within 48 hours of treatment. However, in some cases, croup symptoms may persist for up to a week or longer, especially if the condition is not effectively managed.¹

Can croup turn into asthma?

While croup itself does not turn into asthma, children who have had croup may have an increased risk of developing asthma later in life. Studies have shown that children with a history of croup are more likely to develop asthma, although the exact mechanisms underlying this association are not fully understood. ¹⁰

When to worry about croup?

Parents should seek medical attention if their child experiences severe or worsening symptoms of croup, such as difficulty breathing, stridor at rest, cyanosis, or signs of respiratory distress. Additionally, if a child's symptoms do not improve with home remedies or standard treatments, a trip to the hospital is necessary.⁴

Summary

• Croup is a group of infections in the upper respiratory tract of young children, occurring in the colder times of the year. It is characterised into mild, moderate or severe based on the severity of symptoms
• Severe croup is a life-threatening condition characterised by croup symptoms such as barking cough, noisy breathing or stridor, sucking in of the skin between the ribs called chest retractions and a bluish tinge in the skin called cyanosis
• The treatment involves urgent admission into the hospital. First, the oxygen levels are improved through oxygenation, then fluid levels are maintained through an intravenous line and then medications like epinephrine and dexamethasone are administered to reduce the swelling in the airways
• The long-term effects of a severe croup episode include increased susceptibility to respiratory infections, increased risk of asthma in adolescence, lower lung function in comparison with peers, psychological distress and comparatively higher rate of cardiovascular diseases in adults (if the episode of croup leads to developing a chronic respiratory disorder like asthma).5. Some ways to prevent long-term complications include regular follow-up and monitoring post-severe croup events, adhering to the correct dosage, technique and timing of taking medication, a healthy lifestyle and balanced diet, breathing exercises under the guidance of a respiratory therapist and psychological support for the child and their guardians