HERMES Paediatric Respiratory common mistakes
HERMES Paediatric Respiratory · Understand the traps and how to avoid them.
When asked to assess severity in a child with acute asthma, the candidate quotes adult cut-offs (e.g. peak flow percentage of predicted, or 'silent chest' as the only red flag) instead of paediatric-specific severity markers such as inability to complete sentences or feeds, subcostal recession, and oxygen saturation in air.
Adult respiratory training and most revision resources are adult-centric, so adult thresholds are over-learned and retrieved first under time pressure; peak flow is also often impossible in children under about 5, which pushes candidates toward remembered adult numbers.
What to do instead
Build a one-page paediatric asthma severity grid from the current national paediatric asthma guideline and rehearse it against short vignettes; for every vignette, explicitly state age, ability to talk/feed, work of breathing, saturations, and response to initial bronchodilator before assigning severity.
The candidate interprets an infant's respiratory rate or oxygen saturation using adult normal ranges, or labels a rate 'tachypnoea' without adjusting for age and sleep state.
Normal ranges change markedly through infancy and childhood and are rarely memorised as a table; candidates default to the adult 12-20 range they use daily.
What to do instead
Memorise and apply age-banded normal ranges (neonate, infant, preschool, school-age) and always state the age band used; in exam answers, write the observed value alongside the expected range for that age so the marker can see the adjustment.
The candidate manages a child with noisy breathing by pattern-matching the sound ('wheeze') to a diagnosis without first distinguishing inspiratory stridor from expiratory wheeze and without considering the level of obstruction.
Wheeze is the most familiar paediatric respiratory sign and is over-applied; stridor is less commonly encountered in general training, and audio descriptions in vignettes are easy to skim.
What to do instead
Adopt a fixed first step for any noisy-breathing vignette: phase of respiration (inspiratory/expiratory/biphasic), level of obstruction (upper vs lower), and then differential. Practise classifying ten short sound descriptions into stridor, wheeze, grunting, and stertor before choosing management.
The candidate investigates a child with recurrent or persistent 'wheeze' or chronic cough for asthma and starts inhaled corticosteroids without considering alternative diagnoses such as inhaled foreign body, structural airway abnormality, cystic fibrosis, primary ciliary dyskinesia, or tuberculosis.
Asthma is common and the reflex answer; red-flag features (onset in the first year of life, failure to thrive, focal signs, clubbing, chronic productive cough, systemic symptoms) are not systematically checked.
What to do instead
Before committing to asthma, run a structured red-flag screen and state it in the answer: age at onset, growth, focal or unilateral signs, clubbing, chronic sputum, systemic symptoms, and response to bronchodilator. If any red flag is present, name the alternative diagnosis and the first-line test for it.
The candidate describes the management of acute bronchiolitis using interventions that are not indicated, such as routine bronchodilators, corticosteroids, antibiotics, or routine chest physiotherapy, rather than supportive care with oxygen, hydration, and escalation criteria.
The urge to 'do something' and transfer of asthma management onto a wheezing infant; many candidates also confuse bronchiolitis with recurrent viral wheeze.
What to do instead
Learn the supportive-care bundle plus the explicit escalation criteria (apnoea, increasing oxygen requirement, exhaustion, poor feeding, age under 3 months or prematurity). In practice questions, justify each withheld treatment with the reason it is not indicated, which demonstrates the reasoning rather than just the list.
The candidate answers a question about a child with a chronic respiratory condition by describing adult management, for example adult dosing of inhaled corticosteroids, adult cystic fibrosis regimens, or adult home oxygen criteria, without scaling to weight, age, and device.
Adult protocols are readily recalled and dose calculations under time pressure are error-prone; device choice (spacer plus face mask versus mouthpiece) is often ignored entirely.
What to do instead
For every drug answer, state dose per kilogram or age-banded dose, the delivery device appropriate to age, and the monitoring parameter. Keep a personal table of paediatric respiratory drug doses and device-by-age choices and rehearse it weekly.
The candidate describes a procedure such as pleural aspiration, chest drain insertion, or foreign body removal without stating the site, depth, imaging, and safety steps specific to children (e.g. safe triangle in a small chest, ultrasound guidance, sedation and analgesia, and the need for senior support).
Procedural knowledge is often learned from adult descriptions; paediatric anatomical differences and the need for age-appropriate sedation are under-emphasised in general revision.
What to do instead
For each core procedure, write a fixed answer skeleton: indication, consent, imaging and site selection, analgesia/sedation, technique, confirmatory check, and complications. Include the paediatric-specific modification explicitly in each skeleton.
The candidate gives a management plan for a child with an acute respiratory presentation without stating the immediate resuscitation and monitoring steps, jumping straight to the diagnosis-specific treatment.
Examination technique focuses candidates on reaching a diagnosis, and acute paediatric assessment (airway, work of breathing, circulation, saturations, glucose) is often assumed rather than written.
What to do instead
Use a fixed opening paragraph for every acute vignette: airway, breathing (rate, work, saturations, air entry), circulation, conscious level, glucose, and immediate actions (positioning, oxygen target range, monitoring, IV access, senior help). Then proceed to diagnosis-specific management.
The candidate interprets a chest radiograph or blood gas in a child using adult reference values or adult pattern recognition, for example treating a child's compensated respiratory acidosis or a normal-looking neonatal chest film as reassuring.
Paediatric reference ranges and normal appearances differ by age, and neonatal and infant films are difficult to read; candidates rely on pattern matching from adult practice.
What to do instead
Learn age-specific blood gas ranges and the common paediatric radiographic patterns (neonatal lung volumes, thymic shadow, viral versus bacterial infiltrates). In answers, state the reference range or expected appearance for the child's age before interpreting the result.
The candidate writes a safe-sleeping, home-oxygen, or discharge-planning answer that omits the family and safeguarding dimension: parental smoking, housing, adherence, immunisation status, and who will monitor the child at home.
Clinical revision tends to focus on pathophysiology and drug treatment; social and preventive aspects are treated as optional extras rather than examinable content.
What to do instead
End every chronic or discharge-planning answer with a standard paragraph covering smoking cessation advice, immunisations, inhaler technique and adherence, written action plan, follow-up interval, and safeguarding or social concerns where relevant. Rehearse this paragraph until it is automatic.