Winter is Coming: Bronchiolitis Update for 2025

This has been well covered by DFTB so have a wander over there.

To summarise: it’s mostly a self-limiting viral infection predominantly in the under 3s, causing coryza, fever, and shortness of breath.  Auscultation may reveal a wheeze and upper airway sounds. Symptoms typically last 7-10 days, usually peaking at nights 2-3, with a cough that can persist for up to four weeks afterwards. It’s most commonly caused by RSV (80% of cases) which is really infectious. Treatment is generally supportive.

Risk factors for severe infection

Children who are at risk of severe infection should be admitted for observation, even if symptoms are mild. It is important to remember that approximately half of children with severe infections do not have any risk factors for severe infection. These risk factors are:

• Less than 1yr, particularly if <6 weeks old
• Ex-premature infants
• Chronic respiratory illness
• Pulmonary hypertension
• Previous bronchiolitis requiring CPAP or PICU admission
• Immunodeficiency
• Inborn errors of metabolism
• Cystic fibrosis
• Trisomy 21

Is it bronchiolitis or is it viral-induced wheeze?

Generally, the younger the child, the less likely they are to have bronchospasm.

Wheeze in babies under 1 year of age is usually caused by the oedema and mucus of bronchiolitis narrowing the airways; no amount of bronchodilator will help with that.

Newborns may present with apnoeas. Starting high-flow won’t help with these. Get PICU and senior paeds help and consider caffeine IV if they are pre-term.

Children over the age of 2 are more likely to have bronchospasm, so the wheeze comes on more quickly (hours not days) and is more likely to respond to bronchodilators. In that middle group, aged 1-2 years, if you’re not sure, a trial of inhalers is not evidence based, but may help you make the diagnosis. Make sure that the same person listens before and then again 10-15 minutes after treatment. Plenty of things can confound this; a child who screams through 10 puffs of salbutamol may well shift that mucus plug causing their wheeze and falsely reassure you that it was your treatment that helped, so keep an open mind.

What else could it be?

Focal crepitations and lack of wheeze suggest pneumonia rather than bronchiolitis or viral wheeze – if the child’s well, the treatment is the same, anyway. If the child requires intubation, you’ll be getting an X-ray. It’s important to note that most respiratory conditions in children do not need an X-ray unless they are very unwell and it doesn’t change management other than to increase unnecessary antibiotic prescribing.

Congenital cardiac abnormalities are predominantly picked up prior to discharge from postnatal care, however undetected abnormalities can lead to congestive cardiac failure (CCF) which can mimic symptoms of bronchiolitis. Clues will be in the examination and history; excessive tachycardia, hepatomegaly, and a murmur will point you towards CCF, as will the child not following the typical pattern of illness, peaking at days 2-4 and then improving.

Keep in mind that just because your practice is evidence based, doesn’t mean that everyone else’s is. You are likely to see variations on the practice outlined here, and it is always good to (politely) question accepted norms. Some departments are much better at this than others.

Edward Snelson @sailordoctor describes assessment and decision-making in bronchiolitis really nicely here and talks about wheeze and the causes at different ages here.

Generally, bronchiolitis is self-limiting and treatment is supportive. Nasal or upper airway suctioning risk trauma, and for this reason it’s not recommended. Although bacterial infection can co-exist, these children generally aren’t given antibiotics.

Don’t give bronchodilators, adrenaline nebulisers, hypertonic saline, steroids, Montelukast and, most importantly,  no trial of inhalers (see also gppaedstips.) Your paediatricians will consider giving at risk children Palivizumab – a monoclonal antibody.

The main indications for admission to hospital (aside from observation in more vulnerable patients as above), are for apnoeas (observed or reported), persistent severe respiratory distress (RR>70, marked chest recessions, grunting), or when respiratory support or rehydration is required.

Rehydration and fluid maintenance

Make sure to take a clear history on the child’s normal oral intake when they are well and at present as they are sick – for younger children parents will often talk in terms of “bottles” or ounces. If taking less than 50% of their usual feeds, nasogastric feeding may be needed. Children requiring high flow O2 can still have NG feeds. Isotonic fluids intravenously may be needed for impending respiratory failure or those unable to tolerate NG.

IV or NG fluids? How and when to pass an NG in children?

We thought earlier about when to do a CXR. The same goes for IV access. Think about why you need it. Are you considering a bacterial LRTI and therefore considering IV antibiotics? Or will a cannula just upset a miserable child who can be hydrated using NG feeds?

The official line is to admit and consider NG tube feeding for babies taking less than about half of their usual feeds. There’s a feeding calculator available on Twitter.

Image from Twitter awaiting permissions

In reality, if a baby is appearing to have moderate to severe respiratory distress and/or looking tired I would pop an NG down and see how they do with a bottle or breast feed. If it looks like they’re too tired to maintain feeding orally and they aren’t tolerating “little and often” feeds, use that NG tube. It will conserve their energy for respiratory effort and avoids the need for IV fluids.

A survey of parents of children who required both NG and IV insertion reported 80% of parents would select NG over IV rehydration given the choice (Srinivasan 2017). Babies are less likely to feel hungry, so less likely to get unsettled, plus enteral feeding is always a better option, physiologically.

If we are heading towards intubation the NGT will be useful to keep in. Don’t forget, an upset baby will cry and swallow lots of air, which will distend the stomach and splint the diaphragm, making respiratory distress worse – aspirating the NG tube can help with this. Babies needing bag-mask ventilation also benefit from NG aspiration for the same reasons, especially just prior to intubation.

NICE guidelines advise IV fluids in children who do not tolerate NG feeds, or have impending respiratory failure.

For tips on how to put an NG in, look at DFTB and remember, confirm the position according to local policy before starting any feed.

Give oxygen if saturations are persistently less than 90% for children over 6 weeks, or less than 92% in babies under 6 weeks or children of any age with underlying health issues. In most cases you’ll start with nasal cannulae, and escalate to high-flow humidified nasal oxygen (Optiflow, Airvo, Vapotherm) if saturations can’t be maintained on “normal” oxygen. Make sure to speak to your paeds team early!

Consider CPAP for impending respiratory failure, with discussion with PICU or your local retrieval service.

The next step from here is intubation and ventilation.

Using high-flow, humidified nasal cannula oxygen

High-flow, humidified nasal cannula oxygen (HFNC) is used when we’re unable to keep the oxygen saturations above 92% on standard oxygen therapy. There is no evidence for using HFNC for early treatment for bronchiolitis in ED, and if you want to read more about the evidence for its use in ED check DFTB  here and here.

Before you start HFNC, check your local guidelines – most places will need this child cared for in HDU, and this has a huge impact on capacity. In many trusts, this is a Consultant Paediatrician decision, because of the implications of starting, or not starting. Also, this is an AGP, so if the child is in your ED and they need to get to paeds, you can’t move them down the corridor on it. Can they transfer first and start NIV in HDU?

Use the airvo2 app to help – even if you’re an experienced optiflow user, it just helps you remember what the buttons do!

Summary of main steps:

Review label on machine or see instruction video here. There’s also a quick reference guide here. The pictures below illustrate the process wonderfully, but we’re not sure where they came from, so are asking forgiveness for reusing them.

1. Install auto fill water chamber remove the blue port caps, unwind the water tube but leave the water bag spike in the plastic bracket so it stays clean. Fit the chamber adaptor firmly on to the chamber ports. Clip the water tube into position. The chamber is ready. Slot the water chamber into the AIRVO 2.

2. Connect water supply hang the water bag and push the tube spike into the fitting. Open the vent cap and watch the water enter the chamber.

3. Check water level is below the mark if the water rises above the mark, the chamber is faulty and must be replaced.

4. Connect the breathing tube the end with the blue sleeve attaches to the AIRVO 2. Slide the sleeve back, and line up the connector with the port on the top of the AIRVO 2. Push the connector on and slide the sleeve down to lock the breathing tube into place.

5. Attach the nasal cannulae see ‘Commencing Therapy’.

Information video available for cleaning and disinfecting available from fphcare.

When to intubate

Involve the anaesthetic team early if you are clinically concerned regarding the work of breathing, or if the baby is tiring.

It’s challenging for us as emergency medicine practitioners to call the anaesthetic team without numbers like blood gases, but a trend of observations will give you a really good picture of what’s going on.

Also remember the parents! Compare everything to what the parents say is their baseline and re-evaluate frequently so you can determine if the baby is improving, stable, or deteriorating.

If you are considering intubation, get hold of your retrieval service early.

How and when to do a cap gas in children, and how to interpret them

It’s tempting to want to know a blood gas on a patient who appears in respiratory distress, and is often the first thing we consider in our adult patients. However, in our paediatric patients it can be a bit different. Do a blood gas in patients who require escalation of care to NIV (to some, all kids with bronchiolitis look unwell). There is no evidence to support CO2 monitoring in these kids, if oxygen saturations are normal then I don’t think CO2 should change management.

If you’re considering a cannula, don’t upset the child by doing a cap gas first.

To do a cap gas, follow the instructions here or watch this video from DFTB – remember to analyse it immediately as unlike adult samples, it clots quickly!

When interpreting, remember it’s a mixed sample so the pO2 and pCO2 aren’t 100% reliable but everything else should be. For more information look at the RCEMLearning blood gas article.

Chest X-rays

Wouldn’t a chest X-ray be helpful in knowing what is actually going on?

It’s a fine line in bronchiolitis between deciding when to intervene and when to let the child settle and give them a break from handling.

If the clinical exam shows bilateral diffuse crackles and wheeze, and there are no focal signs, it is far more likely to be a bronchiolitis than a LRTI. Routine blood gases and chest X-rays are not recommended. This will only anger the baby and make their work of breathing much harder, plus there’s the whole exposure to radiation to think about, and the ALARA principle (As Low As Reasonably Achievable).

Focal crepitations may suggest pneumonia, however if the child is not severely unwell the treatment is the same and a chest X-ray will not alter your management. Any child requiring intubation will receive an X-ray.

More on chest X-rays here and investigations here.

Viral swabs

Swabs won’t help with clinical management (viral respiratory illnesses all need a similar treatment pathway), but may help with infection control and cohorting of babies with similar causative organisms. Some Trusts no longer cohort children with RSV or treat them any differently from those with other viruses.  POC RSV and flu testing is now common and you may not need a full viral PCR, although local guidance might require this. Following the COVID-19 pandemic extended viral swabs have become more commonplace for children being admitted with severe bronchiolitis, rather than an NPA. Keep in mind that nasal swabs are less accurate than aspirate swabs (and adc.bmj.com).

Although bronchiolitis can occur at any time of the year the annual surge in winter is inevitable and can be a demand on your department, both in terms of resources and staff morale. Here are some points to consider:

Start planning for the epidemic NOW!

• Find and update your bronchiolitis guideline!
• Liase with adult critical care about possibility of taking children >12 years as surge capacity.
• Have discussions about utility of POC testing.

Education

• Train all staff in recognition and treatment of bronchiolitis. There are some fab resources to do this asynchronously from elfh and here on DFTB.
• Familiarise yourself with HFNC, in whichever brand you use locally. Ask staff to download the airvo2 app if appropriate.
• Make sure you have a clear and easily locatable bronchiolitis guideline.
• Consider reaching out to mother and baby groups in your areas to educate them about bronchiolitis and when to worry (and when not to!).
• Consider a patient questionnaire so you can get lots of information from them quickly, without having to ask it. We made an example proforma here – please review it, use it, modify it, and feedback.
• Consider a bronchiolitis clerking pathway, preferably one that enables single clerking. (Send us your clerking examples – #RCEMBronch)

Have discussions about a bronchiolitis follow-up clinic so you can send home your day 3 bronchiolitic baby, knowing they will get a day 4 and onwards review when they are likely to be at their peak. If anyone does this, please get in touch and let us know how it works!

There’s a nice summary infographic here from Twitter.

Equipment

• Do you have enough high-flow consumables? How quickly can you get them?
• Does Paeds have enough piped oxygen?
• Do you have enough paediatric non-rebreathe masks and enough nasal cannulae?
• Do you have enough NG tubes and pH strips?

Infection Control 

• Consider infection control posters in all rooms and staff areas.
• Arrange extra cleaning to reduce fomite spread.
• Make sure you have enough aprons and gloves available.
• Educate all staff about the importance of infection control.

Wellbeing

All the links we shared for Covid wellbeing are really important. It’s likely your workforce are tired (yes, paeds were busy and redeployed too). This epidemic is likely to receive less media attention than Covid and this might mean parents are less understanding, especially as children are more emotive. This is going to make it hard. So…

• Arrange regular debrief or Balint groups. Yes you’re busy, but yes they’re important.
• Publicise those wellbeing contact details.
• Get AL and rest in… now.

The CATs webinair: Recorded here
RCPCH webinair: Recorded here
Paediatric Critical Care Society: 15th July. Details here

Guidelines
EMBRACE Generic Guidelines including intubation checklists.

References

• #EM3, Carl Van Heyningenm updated version here, old but discussed version Lightning Learning: Bronchiolitis.
• RCEMLearning, Snelson E. Coughing, Wheezy and Stridulous Children
• RCEM Local Guidelines Paediatric Bronchiolitis
• Henry Goldstein. Bronchiolitis, Don’t Forget the Bubbles, 2013.
• Andrew Tagg. Nasogastric tubes, Don’t Forget the Bubbles, 2018.
• Andrew Tagg. COVID and RSV, Don’t Forget the Bubbles, 2021.
• Ben Lawton. Following bronchiolitis guidelines, Don’t Forget the Bubbles, 2021.
• Tessa Davis. Bronchiolitis guidelines, Don’t Forget the Bubbles, 2018.
• RCEMLearning, Abela N, W is for Winter.. and Wheeze: Paediatric Acute Asthma. 2016.
• NICE, Bronchiolitis in children: diagnosis and management. [Guideline NG9].  Published: 01 June 2015. Updated 2021.
• Respiratory Syncytial Virus (RSV) – Guidance for the Management of Ratified by: Infection Control & Decontamination Assurance Group: 3rd August 2017. Review date: March 2022.
• Public Health England, Respiratory syncytial virus (RSV): symptoms, transmission, prevention, treatment. 22 August 2008.
• Intensive Care Society Policy Statement
• DFTB Bronchiolitis

Test Yourself

RCEMLearning, Moore  AM, The Unhappy Wheezer. 2019.