Croup in children, the barking cough at night

Croup is a viral infection that swells the voice box and windpipe in young children. It causes a harsh, barking cough, a hoarse voice and sometimes a noisy breath in. Most cases are mild and settle in two to three days. A single dose of a steroid medicine works well, and a few signs mean you should go to hospital straight away.

What is croup?

Croup is swelling of the upper airway, mainly the voice box (larynx) and windpipe (trachea), caused by a virus. It is most common in toddlers and young children.

A child's airway is narrow, so even a little swelling makes a big difference to airflow. It usually starts like an ordinary cold with a runny nose and mild fever. Then, often at night, the barking cough begins. Croup is diagnosed from the sound and a careful examination. Blood tests and X-rays are rarely needed.¹

What does croup sound like?

The croup cough sounds like a seal or a dog barking. Many parents tell Dr Dutta it woke the whole house.

The voice may be hoarse and the cry croaky. Some children also make a high-pitched, harsh noise when breathing in. This noise is called stridor. A barking cough with no stridor at rest is usually mild croup. Stridor when your child is calm or asleep means the airway is more narrow and needs a doctor promptly.

What is stridor and when is it an emergency?

Stridor is a harsh, squeaky sound heard when a child breathes in through a narrowed upper airway. Stridor while your child is calm or resting is an emergency sign.

Stridor only during crying or coughing is common in croup and less worrying. Go to hospital at once if your child has:

• Stridor at rest or during sleep.
• The skin pulling in at the neck, between the ribs or below the ribs with each breath.
• Drooling, trouble swallowing, or refusing to talk or drink.
• Blue or grey lips, or a pale and sweaty look.
• Unusual sleepiness, agitation or a sudden quiet after hard breathing.

A child who becomes quiet and drowsy after a long struggle may be tiring, not improving.

Why is croup worse at night?

Croup often flares between late evening and early morning. The exact reason is not fully known.

Lying down and the upset of waking suddenly may play a part. Crying makes the swelling feel worse because the child breathes faster and harder through a narrow airway. So the first thing to do is to stay calm and keep your child calm. Hold your child upright on your lap and speak softly. Your calm breathing helps more than you might think.

Does steam or a humidifier help croup?

No good evidence shows that steam helps croup, and hot steam can cause burns. Dr Dutta does not recommend it.

A review of trials found that breathing humidified air did not meaningfully improve croup scores in children with mild to moderate croup.² For decades parents were told to sit in a steamy bathroom. We now know the steroid medicine is what makes the real difference. If you want to sit in a bathroom with your child to calm them, keep well away from hot water and never use a bowl of boiling water.

Does cold air help croup?

Cool fresh air may ease croup for a short while. It is fine to try, but it does not replace a doctor's assessment.

In a trial in Switzerland, children who sat outside in cold air (below 10 degrees C) for 30 minutes after getting a steroid improved more quickly than those kept indoors.³ Kolkata winters are rarely that cold, so the effect here may be smaller. Standing by an open window, or near an AC on a cool setting, while you get ready to see a doctor is reasonable. Keep your child warmly wrapped.

Which medicine treats croup?

A single dose of a steroid medicine, usually dexamethasone given by mouth, is the main treatment for croup. It reduces airway swelling and works within hours.

A Cochrane review of 45 trials with almost 6,000 children found that steroids reduced croup symptoms within 2 hours and the effect grew over the next 12 hours.⁴ Even children with mild croup benefit. In a trial of 720 children with mild croup, one dose of dexamethasone halved the number who had to return for more care (7 percent compared with 15 percent) helped children lose less sleep, and reduced parents' stress.⁵

The dose is worked out from your child's weight by a doctor. Do not give leftover steroid tablets at home without advice.

Is prednisolone as good as dexamethasone for croup?

Yes. A large trial found that a lower dose of dexamethasone, or prednisolone, worked as well as the standard dexamethasone dose.⁶

This matters in India because prednisolone is cheap and widely available. Your doctor will pick what suits your child. One dose is usually enough, and a second dose is only sometimes needed the next day.

What happens in hospital for severe croup?

In hospital, children with severe croup get a steroid plus an adrenaline (epinephrine) nebuliser. Adrenaline shrinks the swelling quickly, but the relief is temporary.¹

Because of this, a child who gets adrenaline is watched for a few hours afterwards to make sure the stridor does not return. Oxygen is given if levels are low. Very few children need a breathing tube. Most children go home the same day or after one night.

Do antibiotics or cough syrups help croup?

No. Croup is caused by viruses, so antibiotics do not help. Cough syrups do not help either and can make a child drowsy, which hides warning signs.

Paracetamol in the right dose for weight can ease fever and a sore throat. Fluids help. The rest is time and the steroid dose if your doctor advises it.

How long does croup last?

Croup is usually short. Most children are much better within 2 days, though a mild cough and runny nose can last a week.

A systematic review found that croup symptoms had settled by about 2 days in 9 out of 10 children.⁷ The barking cough is often worst on the first or second night. Some children have a lighter repeat episode the following night, so keep an ear open even if the day seems fine.

Is croup contagious?

The viruses that cause croup are contagious, but most people who catch them just get a cold. Only some young children develop the barking cough.

Spread is through coughs, sneezes and hands. Wash hands often, and keep a child with fever at home from playschool until the fever has gone. Siblings may catch a cold but often do not get croup.

Can croup come back?

Yes. Some children have croup more than once, usually with a new cold. Most outgrow it as the airway gets bigger.

If your child has croup many times, croup at an unusual age such as under 6 months, or noisy breathing between illnesses, your paediatrician may look for another cause, such as a narrow airway from birth, reflux or allergy. Croup-like symptoms that start very suddenly without a cold can also mean a swallowed or inhaled object.

How can I care for croup at home?

Keep your child calm, upright and comfortable, and watch the breathing closely through the night.

• Hold your child on your lap and read or sing quietly.
• Offer small sips of water or breastfeed often.
• Give paracetamol for fever or discomfort, in the right dose for weight.
• Keep the room free of smoke, incense and mosquito coils.
• Sleep in the same room for a night or two so you can hear any change.

When should I take my child to a doctor or hospital?

See a doctor the same day for any child with a barking cough, so a steroid dose can be considered. Go to hospital immediately if you notice:

• Stridor (a harsh noise on breathing in) while calm or asleep.
• Chest or neck pulling in with breathing, or fast breathing.
• Drooling, difficulty swallowing, or sitting forward to breathe.
• Blue, grey or very pale lips or face.
• Your child is very sleepy, floppy, or suddenly quiet after struggling.
• High fever with a very unwell look.
• A baby under 6 months with croup-like breathing.
• Symptoms that began suddenly after choking on food or a small object.