Bronchiolitis

Common in winter months (peak Oct to Mar) in infants under 12 months age; and becoming one of the commonest reason for paediatric admissions in winter.

Commonest cause is Respiratory Syncytial Virus

Also caused by Influenza, Rhinovirus, Parainfluenza, Human metapneumovirus, etc

History key features:

– Onset, sequence and duration of symptoms

– Was there coryza & cough at onset?

– When did breathlessness start?

– Noisy breathing, wheezy/ Grunting/ Stridor?

– Fever? Rigors?

– Any apnoea/ colour change?

– Poor feeding? Taken at least 50% of usual in 24h?

– Passing urine? When last PU?

– Any known illness or immunodeficiency? 

– Born prematurely? Chronic Lung Disease?

Examination:

– ABC; Looking unwell? 

– Apnoeas (esp if <6mo) ?

– Check HR, BP, RR, Temp, SaO2

  Cyanosis? Tired? Lethargic?

– ‘Bronchiolitic’ wet cough

– Increased work of breathing

  Nasal flare, Head bobbing,  

  Subcostal recessions, grunting

– RS: fine inspiratory crepts/ wheeze

High risk of severe disease (requires admission):

– Young infants (especially <3mo age)

– Born preterm

– Chronic Lung Disease

– Congenital Heart Disease

– Downs syndrome/ other anomalies

– Neuromuscular disorder/ Hypotonia

– Immunodeficiency

Investigations:

– Generally none for mild/ mod illness

– CXR if diagnostic uncertainity/ 

  likely secondary infection/ very unwell

– ABG/ CapGas if impending 

  respiratory failure

– Blood culture/ FBC/ CRP if 

  suspecting secondary infection

Common problems include:

1) Feeding management may need NGT/ IV fluids

2) O2 requirement to keep SaO2 >90%

3) Apnoeas, may require ventilation

4) Respiratory failure needing CPAP/ High-Flow/ Ventilation

5) Secondary infection/ sepsis needing antibiotics

 

Can be discharged after assessment if:

– Milder symptoms

– Older infant >6m

– No high risk factor

– Feeding well

– SaO2 >92% in air

– Warning symptoms explained

– Adequate safety-neting

Admission required if:

– Any high risk factor

– Appearing ill/ lethargic

– Moderate/ Severe illness with

– Marked recessions/ grunting

– Apnoeas

– SaO2 persistently <92% in air

– Feeding affected 

  (taking <50% of usual)

– Difficult social circumstances

– Early illness, day 1-2 as likely

  to worsen and peak at day 3-5

None. There is a perceived idea that nebulised hypertonic saline may loosen secretions (such as in Cystic Fibrosis) but this is not proven in bronchiolitis. In a large open label ‘SABRE’ study, nebulised hypertonic saline did not improve immediate feeding or reduce duration of hospitalisation in bronchiolitis.

 

A recent meta-analysis in 2020 also showed that use of hypertonic saline in bronchiolitis did not affect the length of stay in statistically significant or clinically relevant way. 

 

 

Ref:

Everard ML, Hind D, Ugonna K, et al. SABRE: a multicentre randomised control trial of nebulised hypertonic saline in infants hospitalised with acute bronchiolitis. Thorax 2014;69:1105–12

Heikkilä P, Korppi M Hypertonic saline in bronchiolitis: an updated meta-analysis. Archives of Disease in Childhood 2021;106:102.

Most paediatric units have started using HFNC therapy for moderate / severe bronchiolitis with many anecdotal evidence of reducing need for mechanical ventilation. HFNC appears to be more comfortable, less invasive and has fewer adverse events compared with standard oxygen therapy; and required less nursing input than nasal CPAP.

One systematic review in 2019 suggested HFNC is safe, but there is lack of evidence comparing it with standard O2 therapy or nasal CPAP.

Open-label RCT suggests that HFNC therapy outside PICU is feasible and reduced escalation to mechanical ventilation compared to standard-oxygen.

Ref:

Lin J, Zhang Y, Xiong L, et al. High-flow nasal cannula therapy for children with bronchiolitis: a systematic review and meta-analysis. Archives of Disease in Childhood 2019;104:564-576.

Franklin D, et al. PARIS and PREDICT. High flow in children with respiratory failure: A randomised controlled pilot trial – A paediatric acute respiratory intervention study. J Paediatr Child Health. 2021 Feb;57(2):273-281.

The recent Covid-19 pandemic has raised awareness about air-borne nature of respiratory viruses and increased general hygiene measures within community and hospitals.

Most countries have resorted to intermittent ‘lockdown’ restrictions, encouraged working from home wherever possible, use of facemasks, social distancing measures and emphasis on hand-washing.

These non-pharmacological measures have also resulted in blunting other seasonal respiratory illnesses such as RSV bronchiolitis in young children.

One report from Belgium suggested >99% reduction in confirmed RSV cases.

However, there is also a perceived risk that once the above hygiene measures and social distancing rules are relaxed, there could be a surge in RSV bronchiolitis or the winter wave may show higher peak and longer duration causing an upsurge in hospital admissions.

 

Ref:

Van Brusselen D, et al. Bronchiolitis in COVID-19 times: a nearly absent disease? Eur J Pediatr. 2021 Jun;180(6):1969-1973. 

Ralston SL et al. Clinical Practice Guideline: The diagnosis, management and prevention of bronchiolitis. American Academy of Pediatrics. Pediatrics 2014, 134, e1474-e1502.

NICE guideline: Bronchiolitis (NG9) May 2015.

SIGN. Scottish Intercollegiate Guideline Network. 91, Bronchiolitis in children November 2006.