Master CPS - Paediatrics
for MSRA

What the MSRA Tests in CPS - Paediatrics

CPS - Paediatrics on the MSRA tests clinical problem-solving in children from birth to adolescence. Candidates must recognise acute presentations (e.g., fever, breathlessness, seizures, abdominal pain) and chronic conditions (e.g., asthma, eczema, ADHD). Emphasis is on age-specific physiology, red flags for serious illness (e.g., sepsis, meningitis, intussusception), and evidence-based management per UK guidelines (NICE, BNFc). You must demonstrate safe decision-making around investigations, first-line treatments, and when to escalate or refer. Growth and development milestones, immunisation schedules, and safeguarding are also core.

High-Yield Concepts

• Fever in under-5s (NICE CG160): Use traffic light system: green (low risk) manage at home; amber (intermediate risk) requires observation/urine culture; red (high risk) needs immediate senior review, bloods, and antibiotics. Temperature ≥38°C in <3 months is red. For 3-6 months, ≥39°C is red. Always check capillary refill, neck stiffness, and non-blanching rash.
• Acute asthma exacerbation (BTS/SIGN 2023): Assess severity: moderate (SpO2 ≥92%, PEFR >50%), severe (SpO2 <92%, PEFR 33-50%), life-threatening (silent chest, cyanosis, exhaustion). First-line: inhaled salbutamol (10 puffs via spacer or 2.5-5mg nebulised) plus ipratropium bromide (250-500mcg) in severe cases. Oral prednisolone 20mg (<2 years) or 40mg (2-5 years) for 3 days, or IV hydrocortisone 4mg/kg if vomiting.
• Meningitis and meningococcal septicaemia: In children, classic triad (fever, neck stiffness, photophobia) is often absent; look for irritability, poor feeding, bulging fontanelle (infants), non-blanching rash. Immediate IV ceftriaxone 80mg/kg (max 4g) within 1 hour of suspicion. If pen-allergic, use cefotaxime. Do not delay LP if unstable. Dexamethasone 0.15mg/kg 6-hourly for 4 days if bacterial meningitis confirmed.
• Paediatric basic life support (PBLS) – Resuscitation Council UK: Ratio 15:2 for all ages (single rescuer). Compression depth: at least 1/3 chest depth (~4cm infant, 5cm child). Rate 100-120/min. For choking: back blows (infant) or abdominal thrusts (child >1 year). Defibrillation: 4J/kg for shockable rhythms. Adrenaline 10mcg/kg IV/IO every 3-5 minutes in cardiac arrest.
• Urinary tract infection in children (NICE CG54): In <3 months, refer urgently. For 3 months-3 years: dipstick for leukocyte esterase/nitrite; send urine culture if positive. First-line: trimethoprim 4mg/kg BD or nitrofurantoin 750mcg/kg QDS (if >3 months). Prophylaxis only if recurrent (≥2 UTIs). Renal ultrasound for atypical or recurrent UTI. Always consider constipation as precipitant.
• Growth and development milestones (UK-WHO charts): By 6 weeks: social smile. 6 months: sits unsupported, transfers objects. 12 months: pincer grip, walks with support, says 1-2 words. 2 years: runs, speaks 2-word phrases. 4 years: hops on one foot, tells a story. Red flags: loss of skills, asymmetric motor function, no speech by 18 months. Use centile charts; crossing >2 centiles requires investigation.
• Child safeguarding – non-accidental injury (NAI): Suspect if: bruises in non-mobile infant, patterned marks (e.g., handprint, belt), burns in glove/sock distribution, femoral fracture in <1 year. All suspected NAI requires child protection referral. Skeletal survey for <2 years. Always document mechanism and inconsistency with history. Differential: osteogenesis imperfecta, bleeding disorders.
• Acute gastroenteritis (NICE NG29): Assess dehydration: no signs (0-3%), some (3-5%: dry mucous membranes, sunken eyes, reduced skin turgor), severe (≥5%: shock, very sunken eyes). First-line: oral rehydration solution (ORS) 50ml/kg over 4 hours for some dehydration. Ondansetron (oral 0.15mg/kg) if vomiting persists. Do not routinely use antibiotics. Zinc supplementation (10-20mg/day) for 10-14 days in developing countries.

Common Traps in CPS - Paediatrics Questions

• Do not use amoxicillin for first-line UTI in children; it has high resistance rates – use trimethoprim or nitrofurantoin.
• In febrile child, do not rely on white cell count alone to rule out serious bacterial infection – CRP and procalcitonin are more specific.
• Do not give ibuprofen to children with asthma exacerbation; it can trigger bronchospasm.
• In meningitis, do not delay antibiotics for a lumbar puncture if the child is unstable or has signs of raised ICP (e.g., focal neurology, GCS <13).
• Do not diagnose ADHD solely on parent-teacher reports without using validated rating scales (e.g., SNAP-IV) and ruling out other causes (e.g., sleep deprivation, anxiety).
• In a limping child, do not forget septic arthritis of the hip – urgent aspiration and IV antibiotics (flucloxacillin 50mg/kg QDS) are needed; do not rely on X-ray alone.

How to Revise CPS - Paediatrics for the MSRA

Prioritise NICE guidelines for fever, asthma, UTI, and gastroenteritis – these generate the most questions. Memorise the traffic light system thresholds, asthma severity criteria, and PBLS algorithms. Questions often present a short clinical vignette (e.g., '2-year-old with fever and limp') and ask for the next step in management or diagnosis. Practise recognising red flags quickly and differentiating between similar conditions (e.g., viral vs bacterial pneumonia, gastroenteritis vs appendicitis). Use BNFc for drug doses but focus on first-line choices. Revise immunisation schedule (UK routine, including MenB and rotavirus) and safeguarding principles. Time is tight; do not over-read vignettes – identify age, key symptom, and severity markers immediately.

Practise it: MedLumen has 50 CPS - Paediatrics questions for the MSRA, each with a full explanation and references.