The silent chest phenomenon is the most dangerous clinical finding in acute paediatric asthma — the absence of wheeze in a severely distressed child signals near-complete airway obstruction, not resolution. Wheeze requires turbulent airflow through narrowed bronchi; when obstruction is critical, there is insufficient flow to generate sound. Clinical correlates that accompany a silent chest: markedly increased work of breathing (subcostal, intercostal, and suprasternal recession), tachycardia, pallor or cyanosis, and deteriorating consciousness. Any child who was wheezing and then becomes quiet while still distressed is getting worse. BTS/SIGN severity thresholds to memorise: Moderate = SpO₂ ≥94%, PEFR 50–75%, increased WOB, can speak. Severe = SpO₂ <92%, PEFR <50%, unable to speak/feed, HR >140 (under 5) or >120 (5–12). Life-threatening = SpO₂ <92% + any of: silent chest, cyanosis, poor respiratory effort, exhaustion, altered consciousness. The foreign body inhalation differential is particularly important in pre-school children — approximately 80% of inhaled foreign body cases occur in children under 4 years old. Common objects: coins, small toy parts, nuts, grapes, hard sweets. The clinical pattern: sudden onset of coughing/choking (the inhalation event), followed by asymmetric wheeze (object lodges in a mainstem bronchus — usually the right, which is wider and more vertically oriented). Failure of salbutamol to improve wheeze in a toddler = foreign body until excluded by chest X-ray and bronchoscopy. Note that chest X-ray is normal in 30–40% of FB cases (most FBs are radiolucent).

The viral-induced wheeze vs atopic asthma distinction in pre-school children has critical management implications — VIW is driven by non-specific bronchospasm during viral URTIs without underlying eosinophilic inflammation, whereas early atopic asthma has persistent airway eosinophilia that ICS targets. Multiple RCTs show ICS does NOT reduce VIW episode frequency or severity — meaning a child with pure VIW prescribed daily ICS receives steroid exposure without benefit. The clinical discriminators: VIW has wheeze exclusively with viral URTIs (no exercise, cold air, or allergen-triggered episodes), complete absence of any symptoms between viral illnesses, no personal or family atopic history. Early atopic asthma has multiple trigger types, interval symptoms (wheeze on non-viral days), and atopy. When uncertain, a 6–8 week trial of ICS (beclometasone 200 mcg/day) with reassessment is appropriate — response to ICS in terms of episode reduction supports atopic asthma and justifies continuation. For VIW, intermittent SABA PRN (and possibly intermittent ICS at the start of each viral episode — evidence for this is emerging) is the preferred approach. Vocal cord dysfunction in adolescents mimics exercise-induced asthma so precisely that it is estimated 30–40% of teenagers diagnosed with exercise-induced asthma actually have VCD. The key diagnostic question: does the wheeze/stridor occur on inspiration (suggests VCD — vocal cord adduction restricts inspiration) or on expiration (suggests asthma — expiratory airflow limitation in obstructed bronchi)? Most teenagers cannot answer this accurately, making exercise spirometry with flow-volume loop analysis (showing inspiratory flattening) and laryngoscopy (visualising the paradoxical vocal cord movement) the gold standard investigations.

NICE NG80 (Asthma: diagnosis, monitoring and chronic asthma management, 2017 updated 2021) introduced a significant change to UK asthma diagnosis practice — it requires objective confirmation of variable airflow obstruction for all patients over 5, rather than allowing symptom-based diagnosis alone. The FeNO test is placed first in the diagnostic pathway because it is non-invasive, quick, not affected by recent bronchodilator use, and directly measures the eosinophilic inflammation that ICS targets. A FeNO >35 ppb in a child with typical asthma symptoms supports an ICS-responsive eosinophilic phenotype — this child should be treated. A child with typical symptoms but FeNO <25 ppb may have a non-eosinophilic phenotype (VIW, exercise-induced bronchoconstriction without eosinophilia, VCD) and may not respond to ICS. The practical implication: FeNO can prevent both under-treatment (missing asthma diagnosis) and over-treatment (prescribing ICS to a non-atopic child with VIW). GPs who do not have FeNO can use spirometry + PEFR diary as the objective confirmation. The key quality standard is: do not diagnose asthma and start ICS based on symptoms alone without at least one objective test result. This has been a QOF requirement since 2019 (MAS006 — spirometry confirmation before asthma diagnosis coding).

The 15-minute reassessment after initial salbutamol is the most practically important decision point in acute asthma management in primary care — if a child has received 10 puffs of salbutamol via a correctly used spacer (critical — ensure the spacer is age-appropriate and held correctly) and shows no improvement in PEFR, work of breathing, or SpO₂ at 15 minutes, this constitutes a poor response requiring hospital referral regardless of the absolute severity. The failure to respond to bronchodilator is more prognostically important than the initial severity classification. A common primary care error is giving only 2–4 puffs (the maintenance dose) rather than the acute treatment dose of 6–10 puffs. The British National Formulary clearly states that in acute severe asthma, salbutamol should be given as 2.5–5 mg by nebuliser or 6–10 puffs via spacer, not as the maintenance 1–2 puffs. GPs should keep this dose memorised. The ipratropium addition at moderate-severe severity (4–8 puffs via Atrovent MDI via spacer) is evidence-based and should be routine practice — a Cochrane review showed ipratropium added to salbutamol in the first hour of acute asthma reduces hospitalisation rates by approximately 30% compared to salbutamol alone. Atrovent 20 mcg MDI is the appropriate preparation (not the Atrovent UDV nebules, which require a nebuliser). GP emergency bags should contain salbutamol MDI + spacer + Atrovent MDI.

The near-fatal asthma history flag is a critical patient safety marker — a child who has ever been intubated and ventilated for asthma, admitted to PICU, or required IV bronchodilators carries an ongoing elevated risk of another near-fatal episode independent of current control status. These children must have: a clinical alert flag on their GP records, a personal asthma action plan with specific triggers and escalation steps, PICU-level emergency instructions, a low threshold for same-day hospital referral for any acute episode, and specialist respiratory follow-up at least 3-monthly. NICE NG80 and BTS/SIGN guidelines both identify previous near-fatal asthma as a top-tier risk factor for asthma death. GPs who receive discharge letters from PICU for asthma admissions should proactively create or update the clinical alert on the patient's record before the next routine encounter. The 48-hour post-acute review is a NICE quality standard — it provides the opportunity to: (1) confirm full recovery; (2) assess inhaler technique (the single most impactful intervention — 70–80% of children use their inhaler incorrectly); (3) update the WAAP (personal best PEFR may have changed); (4) consider step-up if this was the 3rd+ oral steroid course in 12 months; (5) identify and address the trigger; and (6) ensure the child has a spare salbutamol at school. This review can be a telephone consultation for mild episodes but should be face-to-face for moderate episodes.

The prednisolone dosing principle in acute childhood asthma is consistently underpractised — the correct dose is 1–2 mg/kg once daily (maximum 40 mg) for 3–5 days. A 20 kg child should receive 20–40 mg prednisolone; not 5 mg, not 10 mg. Studies consistently show GPs systematically underdose prednisolone in acute paediatric asthma, resulting in slower recovery and higher relapse rates. The short course (3–5 days) does not require tapering — adrenal suppression does not occur with courses under 7 days, and abrupt cessation is appropriate. Oral dexamethasone is now an evidence-based alternative to prednisolone for acute asthma in children (SIDREA trial and subsequent meta-analyses) — dexamethasone 0.3 mg/kg OD × 2 days is equivalent in efficacy to prednisolone 1 mg/kg OD × 5 days, with better tolerability (less vomiting, better taste). Some NHS trusts have adopted dexamethasone as their standard acute asthma steroid for children — GPs should be aware of this alternative. The ipratropium bromide acute treatment dose (4–8 puffs of 20 mcg/puff Atrovent MDI via spacer = 80–160 mcg) should be given as 4 separate puffs via the spacer for moderate asthma, and up to 8 puffs for severe. It works additively with salbutamol (different receptor — M3 muscarinic vs beta-2 adrenergic) and significantly reduces hospital admission rates when given in the first hour. It should be a standard component of any moderate-severe acute asthma treatment in primary care.

Montelukast neuropsychiatric effects — the MHRA 2020 Black Triangle warning — are important to discuss at every montelukast prescription: the drug can cause sleep disturbances (nightmares, insomnia), behavioural changes (aggression, irritability, anxiety), and in some children, depressed mood. These effects are reversible on stopping. The GP should: (1) inform the parent/carer at prescription; (2) review at 2–4 weeks specifically asking about sleep and behaviour; (3) document the discussion. The benefit-risk balance for most children remains favourable — montelukast is an excellent drug for atopic asthma, VIW, exercise-induced asthma, and combined asthma-rhinitis. But awareness of neuropsychiatric effects means problems are identified early. The LABA safety issue in children — LABA monotherapy without concurrent ICS is absolutely contraindicated in asthma (increases asthma death risk). LABAs should only be prescribed in children in a combined ICS/LABA formulation (Seretide, Fostair, Symbicort) — never as separate prescriptions. NICE NG80 and BTS/SIGN both emphasise this. GPs reviewing asthmatic children's repeat prescriptions should check that any LABA is co-prescribed with an ICS in the same device.

The school asthma action plan is a separate document from the home WAAP — schools require a specific form that names the child, their personal best PEFR, their prescribed inhalers, the yellow and red zone actions, and emergency contact details. The Asthma + Lung UK and NHS provide free downloadable templates. Research shows that children with a documented school asthma management plan have significantly fewer school-day absences from asthma and fewer acute attacks during school hours than those without one. The WAAP personal best PEFR requires a stable period of good asthma control to establish — it should be the highest PEFR recorded over 2 weeks of twice-daily measurements when the child is well. This personal best is more useful than predicted PEFR (which is based on height and may overestimate what the child achieves) because it reflects the child's individual maximum airway calibre. Update the personal best PEFR at every annual review if the child has grown, as the airways grow with them. The annual height measurement on an ICS is a medicolegal requirement — GPs must document annual height measured on a stadiometer (not estimated), plotted on a centile chart, and compared to the previous year's measurement. Declining height velocity (>1 centile channel crossed) should prompt review of whether ICS dose can be reduced.

The step-down principle is as clinically important as step-up in paediatric asthma management — many children remain on ICS doses that are higher than necessary because GPs are cautious about reducing them. NICE NG80 and BTS/SIGN both specify that once asthma has been well controlled for 3 months, a 25–50% reduction in ICS dose should be attempted, with reassessment after 3 months. The purpose is twofold: (1) minimise systemic exposure to corticosteroids (growth effects, adrenal suppression at high doses); (2) establish the minimum effective dose for that patient. In practice, many children in the UK are maintained on medium-dose ICS indefinitely without regular step-down attempts. An annual review that includes considering whether step-down is appropriate (using the question 'has this child been well-controlled for the past 3 months?') is good practice. Children who have had no exacerbations and no SABA use in the past 3 months are candidates for ICS step-down. Children approaching adolescence may experience spontaneous improvement in asthma severity — the majority of childhood asthma improves substantially by late adolescence, and some children can stop ICS entirely with close monitoring.