Introduction

Acute respiratory failure refers to when your lungs are unable to release enough oxygen into your blood and therefore breathing is very difficult. It is responsible for 20% of the deaths of under five-year-olds around the world.¹ 

It is often caused by factors such as certain types of lung diseases, blockages of the airways, and neuromuscular disorders. It is more dangerous to children than adults because of how their airways are different. In this article, we will explore what acute respiratory failure is in a little more detail, and how it is treated in children.

What is acute respiratory failure in children?

Our respiratory system (breathing system) allows gases (such as oxygen and carbon dioxide) to be exchanged between our body and our external environment. In particular, it provides the body with oxygen and removes carbon dioxide.

When it cannot do this properly, it is referred to as respiratory failure. The sudden onset of this is acute respiratory failure. This can cause shortness of breath and dizziness, and it can even make your extremities such as fingers and toes, turn blue.²

It is a very common issue among the paediatric population (children) and is a frequent reason for their admission to intensive care. This is because children are more susceptible to respiratory failure than adults – in other words, they are more vulnerable to suffering from it than adults.³

Why are children more susceptible to respiratory failure?

Children are known to be more vulnerable to any kind of disease or infection that involves the respiratory system; they often present with more severe symptoms. This is due to the differences between adult's and children’s respiratory systems.³

From when they are born and throughout their childhood, children’s respiratory system is still in the process of developing. This means that:⁴

• Their chest walls are more compliant (soft/flexible) than those of an adult, so it is more difficult for them to draw in enough air to fill their lungs
• Their chest wall has less ‘elastic recoil’ – it does not go back to its original shape as quickly as an adult’s
• Parts of their respiratory system like the pores of Kohn or Lambert (small openings between the air sacs in the lungs) are not formed before the age of 4, so they are more likely to experience problems related to their air sacs
• Their airways are narrower and do not have as much support from cartilage as adults so are more susceptible to being compressed or blocked by diseases

Causes of acute respiratory failure in children

The majority of cases of acute respiratory failure are caused by one of three categories: 

1. Interstitial lung disease: a group of diseases which involve scarring of the lungs
2. Airway obstruction: something blocking the airways and stopping air from getting to the lungs
3. Neuromuscular conditions: disorders/diseases impacting the nerves that control voluntary muscles – the muscles you choose to move

Treatment for acute respiratory failure in children 

In many cases, if a child is suspected of experiencing acute respiratory failure, a healthcare professional will be able to get an idea of the cause and decide how to proceed with treatment following a physical examination. 

Oxygenation therapy

The frontline treatment for acute respiratory failure is oxygen therapy. This is where additional oxygen is supplied to the child to help them breathe, and this can be delivered in different ways. In many situations, children can be treated effectively using a non-invasive form of oxygen therapy. However, in severe circumstances, invasive forms may be necessary. 

In this section, we will explore the different types of oxygenation therapy. Non-invasive ventilation (NIV) – a term used to describe the ventilation process of the child to help their oxygenation without using invasive methods i.e. intubation and tracheostomy. Supplementary oxygen can be administered through nasal prongs which are inserted just inside their nostril or a facial mask covering their nose and mouth. However, if more oxygen is required, a healthcare professional may decide to treat them with high-flow nasal cannula oxygen therapy (HFNC) instead.

High-flow nasal cannula oxygen therapy (HFNC)

High-flow nasal cannula oxygen therapy (HFNC) is a more recently discovered method of supplying someone with additional oxygen, but the difference is that this oxygen has been heated and humidified. This puts less pressure on the lungs and means that the child can breathe in more oxygen without too much effort. The oxygen is delivered through nasal prongs, and the amount and the pressure can be controlled to suit the child’s needs. In the UK, the treatment will often be administered with an ‘Airvo’ machine or an ‘Optiflow’ machine.⁵

Mechanical ventilation  

In severe cases where children require emergency treatment, mechanical ventilation may be used for treatment. For this, the child will be put on a machine called a ventilator which will take over their breathing. It includes non-invasive ventilation and invasive ventilation. Research has shown that non-invasive ventilation can be a very effective treatment for children with acute respiratory failure, with it improving both survival rates and quality of life after treatment. However, whilst there are very few side effects, if used long-term it could have an impact on the facial bone structure.⁶

Non-invasive ventilation

This type of ventilation consists of supporting the child's ventilation without taking full control of it i.e. while the child is awake. Depending on the timing and amount of support that is given different methods of ventilation are applied. Like continuous positive airway pressure (CPAP) and Bi-level positive airway pressure (BiPAP). These NIV methods consist of a mask attached to a machine which is placed on the child’s nose and mouth however with different settings.⁶

Invasive ventilation

A tube called an ‘endotracheal tube’ (ET) will be placed through their mouth and down their windpipe – a process which is called ‘intubation’. Often, the child will be sedated for this process to minimise pain or discomfort. The ventilator will then supply a mix of oxygen and air through this tube to expand the child’s lungs and essentially breathe for them. 

The supply of oxygen can be altered according to the child’s health status. In some cases, the ventilator will breathe for a patient entirely, in others, the patient’s breathing may be assisted by the ventilator. When appropriate, healthcare professionals will change the ventilator parameters to gradually help the child learn to breathe without it.⁷

Tracheostomy

Another treatment option in some emergency or severe circumstances is a tracheostomy. For this procedure, a hole will be made in the child’s neck so that a tube can be inserted into the windpipe to help them breathe. The aim of this procedure in children is to secure their airways and aid recovery. However, this will only be considered as a treatment option where necessary, given that it requires an expert surgeon and a lot of post-operative care.⁸

Treating the underlying cause

Finally, as well as treating the immediate symptoms of acute respiratory failure, the underlying cause will also need to be treated while ensuring adequate oxygenation and ventilation as required. For example, if it has been caused by a respiratory infection, the doctor will evaluate what medications to prescribe to treat the infection – such as antibiotics. Nonetheless, the first actions in handling cases of acute respiratory failure should focus on evaluating the airway, breathing, and circulation (ABC).²

Summary

• Acute respiratory failure is when your lungs cannot release enough oxygen into your blood and breathing becomes difficult
• Children are more susceptible to it than adults because their respiratory systems are still developing
• Acute respiratory failure in children can be caused, among other things, by interstitial lung diseases, an obstruction to their airways or neuromuscular disorders
• Treatment options for acute respiratory failure in children include: 
  • Supplementary oxygen: delivering oxygen through nasal prongs or a mask
  • High-flow nasal cannula oxygen therapy (HFNC): delivering heated, humidified oxygen through nasal prongs
  • Mechanical ventilation: non-invasive such as CPAP or BiPAP or invasive like an ET tube is inserted into the windpipe and connected to a machine which can breathe for the child, or assist their breathing (for severe/emergency cases)
  • Tracheostomy: a procedure where a hole is made into the windpipe to help breathing
  • Treating the underlying cause of the respiratory failure: for example, taking antibiotics for a bacterial infection