Bronchiolitis
Definition
Epidemiology
Pathophysiology
Categories
Symptoms
Investigations
Management
DD
RSV
LRT inflammation
Usually <2yrs; winter; most common LRTI in children <2yrs; leading cause hospitalisation in children <1yr; 3-10%
SBI in children <1/12 presenting with bronchiolitis so do septic screen; 3-5% SBI in children >2/12 with
bronchiolitis, so do urine; 3-4% mortality if co-morbidities, usually <6/12
Cause: RSV (40-70%; 90% children infected by 2yrs), bocavirus (12%), rhinovirus (9%, mild), metapneumovirus
(2%), parainfluenza (1%), influenza (0.5%), coronavirus (0.5%), adenovirus (rare but causes more severe disease)
Pathophysiology: Infection of bronchiolar resp and ciliated epithelial cells  incr mucus secretion, cell death and
sloughing, peribronchiolar lymphocytic infiltrate, submucosal oedema, dynamic + fixed narrowing and obstruction
of small airways, VQ mismatch, bronchospasm, atelectasis, hyperinflation of LRT
Mild: OK
Mod: SOB on feeding, feeding >50%, mod WOB, SaO2 <94%, corrects with O2, brief apnoeic episodes, lethargic,
dehydrated, exp wheeze
Severe: unable to feed (<50% feeds), marked WOB, high O2 requirement, may not fully correct, frequent long
apnoeic episodes, fatigue, CO2 retention, insp and exp wheeze
Worsens 3-5/7, peak day 2-3, plateaus few days, improves over 2/52; apnoea usually occurs in 1st 3/7 of illness
RF for apnoea: <3/12, prem, LBW, co-morbidities, immunodef, chronic lung disease
Bloods: if T>38.5 / <1/12; FBC; U+E (if for IVF; SIADH, decr Na); Blood cultures; VBG (if impending resp failure); do
septic screen if <1/12
NPA: usually not required if >2/12; do if neonate, apnoea, severe, atypical, uncertain diagnosis, in-hospital
infection control; rapid Ag tests 85% sens, 99% spec; PCR higher sens
CXR: only if severe/atypical/suspect complication; hyperinflation, minor infiltrates, peribronchial cuffing,
segmental atelectasis
Urine: do if high fever in neonate (4% may also have UTI)
Apnoea monitor: if <1/12, history / PMH of apnoea
O2 to SaO2 >92% (if cannot maintain SaO2, need PICU assessment); fluids at 2/3 maintenance (bolus and
replacement of deficit over 24hrs if shocked); trial salbutamol if >6-8/12 / history of atopy / previous history of
wheeze (no change in LOS or admission rates if younger; if benefit, give as asthma), NP CPAP (in 3-7%), ABx (if
complicated by 2Y infection)
No benefit: physio, steam, oral decongestants, steroids (no difference in hospitalisation), ipratropium, LT
antagonists, Ig, ribavarin
?benefit: saline drops, suctioning, neb saline/hypertonic saline, palivizumab (monoclonal ab to RSV, monthly
injection in high risk groups, decr hospitalisation and ICU admits), adrenaline neb (no longer term impact), heliox,
caffeine (used in PICU only)
Admit if: mod/severe; <3/12, prem, SaO2 <92%, apnoeic episodes or RF for apnoea, significant dehydration,
severe WOB, co-morbidities, social, <1/12 and RSV +; 40% are admitted
Discharge if: Review within 24hrs, carer education, social circumstances, stable and improving, mild-mod severity,
SaO2 >92% off O2 >4hrs; taking at least 2/3 feeds; RR <45 <2/12, RR <40 6-24/12; mild WOB; adequate PO intake;
no history of intubation / apnoea
GORD, T-O fistula (feeding related), CF, immunodef (recurrent), CCF, myocarditis, epiglottitis, FB (stridor),
trachea/largyngomalacia, pneumonia, asthma, ALTE
Notes from: Dunn, Cameron (adult and child), TinTin, Starship Guidelines