Paeds SAQs · infectious-diseases
Paediatric sepsis: diagnosis, antimicrobial treatment and source control — formative SAQs
Two MedVellum formative short-answer questions on paediatric sepsis, covering Phoenix-criteria recognition, the first-hour bundle (cultures, empiric antibiotic within one hour, judicious fluids, early vasoactives), source control, reassessment and escalation. The marks and timing support transparent self-assessment; they are not an official board format or pass standard.
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Target exams
SAQ 1 — A school-age child with septic shock
Question 1 — 10 formative marks; suggested time 15 minutes [1]
A previously well 7-year-old boy presents with two days of fever and cough. He is now less interactive, mottled from the knees down, and has cool peripheries with a capillary refill of 4 seconds. His heart rate is 150, blood pressure 92/50, respiratory rate 36, and he is oliguric. A venous lactate is 4.2 mmol/L. [1] [12]
- Classify his state using the Phoenix criteria and define the syndrome. (2 marks)
- Outline your first-hour bundle, including the antibiotic timing target and fluid strategy. (4 marks)
- Describe your reassessment loop and the triggers to stop fluids and start vasoactives. (2 marks)
- Justify how the FEAST and Fluids in Shock evidence shapes a cautious fluid approach. (2 marks)
Full-credit answer — SAQ 1
Reveal full-credit answer for SAQ 1
1. Phoenix classification
This child has suspected infection (fever, cough, probable pneumonia) with life-threatening organ dysfunction. His circulatory failure — impaired perfusion, oliguria and a raised lactate — gives him at least one Phoenix cardiovascular point, so he meets both sepsis and septic shock. A normal-range blood pressure does not exclude shock; children are hypotensive late because they compensate with tachycardia and vasoconstriction. [1] [2]
2. First-hour bundle
I would assign a team leader, call the senior paediatric and critical-care teams, attach monitoring and estimate his weight. I would draw two blood cultures from separate sites and a lactate before antibiotics only because it will not delay the first dose; I would add urine and, if stable, cerebrospinal fluid cultures when safe. I would give the first broad-spectrum, weight-based antibiotic within one hour of recognising sepsis — a third-generation cephalosporin, with vancomycin if resistant organisms are possible per local guidance. [3]
For fluids I would give a 10 mL/kg crystalloid aliquot and reassess immediately, repeating only if shock persists and he remains fluid-responsive, and stopping at a locally agreed ceiling rather than chasing a target. This is cold shock, so if he remains poorly perfused I would start adrenaline (epinephrine) as the first vasoactive, titrated to perfusion and age-appropriate mean arterial pressure. [3] [12]
3. Reassessment loop and escalation triggers
After every intervention I would reassess mental state, perfusion, capillary refill, pulse quality, lactate trend, liver size, breath sounds and urine output. I would stop fluids and start or escalate vasoactives if he develops new hepatomegaly, a gallop rhythm, bilateral crackles, a rising lactate despite fluids, or persistent shock with signs of fluid overload. I would involve PICU early and request retrieval before local capability is exceeded. [3] [11]
4. Evidence for a cautious fluid approach
The FEAST trial showed that fluid boluses increased mortality in African children with severe infection, although that population lacked intensive-care rescue; the Fluids in Shock pilot then showed that a restricted-bolus strategy is feasible. Together these support aliquots with reassessment and a ceiling, applied with judgement to the resources that can rescue the child, rather than an uncritical drive to a fixed volume. [8] [9]
Marking grid — SAQ 1
| Domain | Full-credit requirements | Marks |
|---|---|---|
| Recognition & classification | Correct Phoenix classification of septic shock; explains why blood pressure is late | 2 |
| First-hour bundle | Cultures-if-no-delay, antibiotic within 1 hour, fluid aliquots, adrenaline for cold shock | 4 |
| Reassessment & escalation | Loop checks; explicit triggers to stop fluids and start vasoactives | 2 |
| Evidence base | Accurate, setting-aware account of FEAST and Fluids in Shock | 2 |
Common pitfalls — SAQ 1
- Treating blood pressure as the threshold for shock, or continuing fluids past the ceiling.
- Delaying antibiotics for imaging or an unsafe lumbar puncture.
- Forgetting source control (chest imaging, empyema drainage).
- Quoting FEAST uncritically without noting the population and rescue-resource limits.
You have read the opening of this SAQ. The complete unit — every section and its primary-source references — is part of the Paediatrics Fellowship fellowship atlas.
References8Show ledgerHide ledger
- [1]Sanchez-Pinto LN, Bennett TD, DeWitt PE, et al. Development and Validation of the Phoenix Criteria for Pediatric Sepsis and Septic Shock. JAMA, 2024.PMID 38245897
- [2]Schlapbach LJ, Watson RS, Sorce LR, et al. International Consensus Criteria for Pediatric Sepsis and Septic Shock. JAMA, 2024.PMID 38245889
- [3]Weiss SL, Peters MJ, Oczkowski SJW, et al. Surviving Sepsis Campaign International Guidelines for the Management of Sepsis and Septic Shock in Children 2026. Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies, 2026.PMID 41869844
- [8]Maitland K, Kiguli S, Opoka RO, et al. Mortality after fluid bolus in African children with severe infection. The New England journal of medicine, 2011.PMID 21615299
- [9]Inwald DP, Canter R, Woolfall K, et al. Restricted fluid bolus volume in early septic shock: results of the Fluids in Shock pilot trial. Archives of disease in childhood, 2019.PMID 30087153
- [11]Paul R, Niedner M, Riggs R, et al. Bundled Care to Reduce Sepsis Mortality: The Improving Pediatric Sepsis Outcomes (IPSO) Collaborative. Pediatrics, 2023.PMID 37435672
- [12]Bjorklund A, Resch J, Slusher T Pediatric Shock Review. Pediatrics in review, 2023.PMID 37777656
- [13]Rutman L, Richardson T, Auletta J, et al. Association between Child Opportunity Index and paediatric sepsis recognition and treatment in a large quality improvement collaborative: a retrospective cohort study. BMJ quality & safety, 2026.PMID 40345682