Sepsis & Septic Shock for FRCEM SBA: A Practical Guide for Emergency Medicine Doctors


What Is Sepsis & Septic Shock and Why Does It Matter in the ED?


Sepsis is now defined (Sepsis-3) as “life-threatening organ dysfunction caused by a dysregulated host response to infection.” Septic shock is a subset of sepsis where circulatory and metabolic abnormalities are so profound that mortality exceeds 40%—clinically: sepsis with vasopressor requirement to maintain MAP ≥65 mmHg and lactate >2 mmol/L despite adequate fluid resuscitation. (PMC)


In the ED, sepsis is bread-and-butter yet deadly: it’s a leading cause of ICU admission and in-hospital mortality. Early recognition, risk stratification, timely antibiotics, and appropriate fluid resuscitation are core EM skills. NICE’s updated sepsis guidance (NG253/254/255) and the 2021 Surviving Sepsis Campaign (SSC) guidelines emphasise early recognition, prompt risk-based treatment, and escalation when patients deteriorate. (NICE)


From an FRCEM SBA perspective, sepsis and septic shock appear everywhere: triage questions, early warning scores, “1-hour bundle” style management, ICU referral, and pitfalls like missing occult sepsis or over-treating low-risk infection.


How Sepsis & Septic Shock Appear in the FRCEM SBA Exam


Typical question angles:

  • Diagnosis / recognition
    • Distinguishing uncomplicated infection vs sepsis vs septic shock.
    • Applying Sepsis-3 definition, NEWS2, or risk criteria (red/amber flags). (PMC)
  • Risk stratification & triage
    • Using NEWS2, clinical red flags, or age-specific NICE algorithms to decide who needs urgent review, sepsis pathway activation, or ICU referral. (The UK Sepsis Trust)
  • Initial investigation choice
    • Blood cultures, lactate, blood gases, imaging; when to CT vs US vs CXR; when to delay or not delay antibiotics.
  • First-line management
    • ABCDE, oxygen, fluid resuscitation, timing and choice of IV antibiotics, source control, vasopressors.
  • Complications / red flags
    • AKI, ARDS, DIC, septic cardiomyopathy, multiorgan failure.
  • Service / safety themes
    • Early warning systems, escalation failures, “Martha’s Rule”-style escalation of concern. (The Times)


Common formats:

  • Classic vignette: pyrexial, hypotensive, tachycardic patient with suspected pneumonia or UTI.
  • Guideline-based next step: “According to NICE/SSC guidance, what is the most appropriate next step?”
  • Data questions: interpreting NEWS2 trends, rising lactate, or U&E changes.


Example micro-scenario:

A 72-year-old with dementia presents from a care home with confusion, RR 28, SpO₂ 92% RA, BP 88/52, HR 118, temp 38.6°C, lactate 4.1 mmol/L. You suspect pneumonia. What is the single most appropriate next step in management?


Core Concepts You Must Know About Sepsis & Septic Shock


Definitions & Key Criteria


You should be fluent in:

  • Sepsis (Sepsis-3)
    • Infection + acute organ dysfunction, often operationalised as an increase in SOFA score ≥2. (PMC)
  • Septic shock
    • Sepsis + vasopressor requirement to maintain MAP ≥65 mmHg and lactate >2 mmol/L despite adequate fluids. (PMC)
  • Organ dysfunction examples
    • Hypotension, rising lactate, oliguria/AKI, hypoxaemia, altered mental state, coagulopathy, liver dysfunction.
  • Risk tools
    • NEWS2 used across the NHS for deteriorating adults. (The UK Sepsis Trust)
    • NICE age-stratified sepsis risk tables (now split into NG253, NG254, NG255). (NICE)


For exam purposes, don’t forget the lay definition (e.g. UK Sepsis Trust / NG51 legacy): dangerously abnormal response to infection causing organ damage—this often appears in communication/ethics SBAs. (The UK Sepsis Trust)


Assessment & Investigations


History & examination


  • Focus on: 
    • Source: chest, urinary, abdominal, skin/soft tissue, line/device, CNS.
    • Risk factors: extremes of age, immunosuppression, pregnancy/recent pregnancy, surgery, lines, prosthetic devices.
    • Red flag symptoms: rigors, confusion, oliguria, breathlessness, mottling.


Triage and risk stratification


  • Apply NEWS2 at triage and serially; NEWS2 ≥5 (or rapidly rising) is high risk.
  • Use NICE high/medium/low risk criteria by age group; treat “red flag sepsis” as time-critical. (The UK Sepsis Trust)


Key investigations (typical SBA options)


  • Bloods: FBC, U&E, LFTs, CRP, clotting, lactate, blood cultures (pre-antibiotic if no delay). (NCBI)
  • ABG/VBG with lactate.
  • Urinalysis ± MSU.
  • Chest X-ray; targeted imaging (US/CT) if source unclear or to guide source control.
  • Consider ECG and troponin in older/at-risk patients.


Ethically/safety-flavoured SBAs may test taking relatives’ concerns seriously (e.g. “Martha’s Rule” context where family escalate sepsis concern). (The Times)


Initial ED Management


You need a crisp mental model of the first hour:


  • ABCDE and oxygen
    • Treat airway/respiratory compromise; titrate oxygen to appropriate target (e.g. 94–98%, or 88–92% in CO₂ retainers). (Lippincott Journals)
  • IV access and bloods
    • Two large-bore IV lines; send bloods including cultures and lactate early.
  • Fluids
    • SSC 2021 suggests an initial 30 mL/kg crystalloid for patients with hypotension or lactate ≥4, modified by comorbidities. (Lippincott Journals)
    • In the UK ED exam context, think 500–1000 mL bolus, re-assess frequently, more cautious in HF/ESRF.
  • Antibiotics
    • NICE now emphasises risk-based timing rather than blanket “1-hour for everyone”. High-risk (“red flag”) patients should receive IV antibiotics within 1 hour of recognition; lower-risk patients may allow brief further evaluation. (The UK Sepsis Trust)
  • Source control
    • Drain abscesses, remove infected lines, arrange surgical review/IR for collections early. (Lippincott Journals)
  • Vasopressors
    • If hypotension persists despite adequate fluids, start noradrenaline (usually via central line/ICU/HDU setting) and target MAP ≥65 mmHg. (Lippincott Journals)
  • Monitoring & escalation
    • Continuous obs, urine output, repeated lactate; early senior review and ICU outreach where indicated.


Red Flags and Pitfalls


High-yield examable red flags:


  • Hypotension (SBP <90 or MAP <65) or need for vasopressors.
  • Lactate ≥2 (especially ≥4) mmol/L. (PMC)
  • New confusion, GCS drop, or agitation.
  • Oliguria/anuria or rising creatinine.
  • Rapidly increasing NEWS2.


Common pitfalls (and SBA traps):


  • Anchoring on a “simple infection” diagnosis and missing early organ dysfunction.
  • Delaying antibiotics for “perfect” imaging in a high-risk patient.
  • Over-resuscitating fluids in florid pulmonary oedema or end-stage HF.
  • Failing to act on staff or family concern about deterioration.


Special Populations


  • Children
    • Use age-specific NICE (NG254) criteria; tachycardia, tachypnoea, poor feeding, mottling, non-blanching rash, parental concern are big exam flags. (NICE)
  • Pregnant/recently pregnant
    • Atypical physiology; lower threshold for escalation; refer to NG255. (NICE)
  • Elderly/frail
    • Delirium or sudden functional decline may be the main clue; vitals may be only subtly abnormal.
  • Immunocompromised
    • Steroids, chemo, haematological malignancy, transplant; broader differential and aggressive search for source.


Common FRCEM SBA Traps Related to Sepsis & Septic Shock


“Question writers love to test the difference between X and Y…”


  • Sepsis vs septic shock vs severe infection
    • Trap: Calling every septic patient “septic shock”.
    • Fix: Remember septic shock = sepsis + vasopressors + lactate >2 after fluids. (PMC)
  • Useful investigation vs best next step
    • Trap: Choosing CT abdomen when the patient is hypotensive and needs immediate fluids/antibiotics.
    • Fix: In unstable, high-risk sepsis, resuscitation and antibiotics precede non-essential imaging.
  • Treating all “possible sepsis” with immediate broad-spectrum
    • Trap: Giving meropenem within 10 minutes to a well patient with low NEWS2 and minor infection.
    • Fix: Use risk-based timing from updated NICE—1-hour antibiotics for high-risk, more nuanced for low/moderate risk. (The UK Sepsis Trust)
  • Ignoring lactate
    • Trap: Focusing solely on BP and missing high lactate as a marker of tissue hypoperfusion and mortality risk.
    • Fix: Lactate ≥2 (especially ≥4) should prompt urgent reassessment, fluids, and escalation. (PMC)
  • Over-reliance on SIRS
    • Trap: Using SIRS alone to diagnose sepsis or to withhold treatment because SIRS not fully met.
    • Fix: FRCEM will expect familiarity with Sepsis-3 and organ dysfunction, not purely SIRS.


High-Yield Clinical Patterns for Sepsis & Septic Shock in the ED


Classic Presentation


Age: 68History: 2 days of fever, productive cough, increasing breathlessness.Obs:HR 120 bpmRR 30/minBP 84/50 mmHgTemp 38.9°CSpO₂ 90% on airGCS 14 (confused in time)Lactate 4.2 mmol/LCXR: Right lower-lobe consolidation. Creatinine rising from baseline 80 to 160 µmol/L.


Pattern: Pneumonia with sepsis and septic shock (hypotension + high lactate despite initial fluids). Expect questions around immediate resuscitation, antibiotic choice, and ICU referral.


Atypical Presentation


Age: 82History: Brought by family with 24 hours of “not herself”, off legs, incontinent, no clear focus.Obs:HR 96 bpmRR 22/minBP 108/64 mmHgTemp 37.8°CSpO₂ 95% RAGCS 14 (confused, worse than baseline)


Here, vitals aren’t dramatic, but new confusion and functional decline with raised inflammatory markers and early AKI point to sepsis without shock and high risk due to age/frailty—great for SBAs testing subtle sepsis and escalation decisions.


Dangerous Mimics


Differentials FRCEM loves to contrast with sepsis:

  • Cardiogenic shock
    • Hypotension, cool peripheries, pulmonary oedema, raised JVP; echo/BNP and history of cardiac disease help distinguish.
  • Anaphylaxis
    • Rapid onset, urticaria/angioedema, bronchospasm; often no infection focus, responded to adrenaline.
  • Adrenal crisis
    • Hypotension, hyponatraemia, hyperkalaemia, known steroid use or pituitary disease.
  • Pulmonary embolism
    • Pleuritic chest pain, sudden dyspnoea, risk factors (surgery, cancer, immobility), possible fever but usually different pattern.


Being able to tease these apart quickly is exam-gold.


How to Revise Sepsis & Septic Shock Efficiently for the FRCEM SBA


Use Question Banks First, Then Guidelines


  1. Do blocks of 20–40 sepsis/septic shock SBAs: 
    • Adult, paeds, pregnancy, immunocompromised.
  2. Review explanations in detail, noting: 
    • Definition and risk stratification used.
    • Why that investigation/management step was “best next”.
  3. Then skim the key guideline sections: 
    • NICE suspected sepsis (NG253–255) – risk tables, antibiotic timing, escalation. (NICE)
    • 2021 Surviving Sepsis Campaign – bundles, fluids, vasopressors, source control. (Lippincott Journals)
    • Any local/RCEM sepsis toolkits in your trust or RCEM resource library. (RCEM)


This keeps your mental model aligned with real UK/International practice, not outdated “all antibiotics within 60 minutes for everyone” dogma.


Build Mini-Notes or Flashcards from Mistakes


Every time you miss a sepsis SBA:

  • Write what it tested: 
    • “Timing of antibiotics in moderate vs high-risk sepsis.”
    • “Definition of septic shock.”
  • Write why you were wrong: 
    • “I overlooked lactate; focused only on BP.”
    • “I chose CT before stabilising the patient.”
  • Finish with a one-liner rule: 
    • “High-risk (red-flag) sepsis: IV antibiotics within 1 hour of recognition; don’t delay for imaging.” (The UK Sepsis Trust)
    • “Septic shock = sepsis + vasopressors to keep MAP ≥65 + lactate >2 despite fluids.” (PMC)


These make perfect “last-week” flashcards.


Mix Text-Based and Image-Based Questions


  • Combine vignette SBAs with: 
    • CXR images (pneumonia, ARDS).
    • US/CT clips (empyema, abscess, obstructed uropathy).
    • Charts of NEWS2 trends or shock indices.
  • Practise reading time courses: 
    • How lactate or creatinine evolves.
    • Response after first fluid bolus.


This mirrors real FRCEM SBA pattern recognition and OSCE prep.


How StudyMedical Covers Sepsis & Septic Shock in Its FRCEM SBA Question Bank


StudyMedical has a large spread of curriculum-mapped sepsis and septic shock questions across adult, paeds, and special populations, aligned with the RCEM 2021 curriculum and FRCEM blueprint.


For this topic, you can highlight that the bank includes:

  • Full-vignette sepsis SBAs
    • Each with complete vitals, ED context, and realistic investigations—pneumonia, UTI, meningitis, biliary sepsis, neutropenic sepsis, post-operative sepsis.
  • Image-based SBAs
    • CXRs, CT abdomens, echo snapshots, US clips and observation charts relevant to sepsis and shock patterns.
  • Guideline-anchored explanations
    • Explanations that explicitly reference NICE sepsis guidance, Surviving Sepsis Campaign 2021, and UK practice (NEWS2, red flag sepsis, antibiotic timing). (NICE)
  • Smart revision modes
    • New, Incorrect, and Flagged question filters so you can repeatedly hit the sepsis/shock cases you find trickiest until they’re automatic.


FAQs About Sepsis & Septic Shock in the FRCEM SBA


How often does sepsis appear in the FRCEM SBA exam?


Very often. Sepsis and septic shock cut across resus, acute medicine, PEM, ICU and ethics/safety, so you’ll see multiple questions per diet, both clinical and system-focused.


What’s the single most important thing to remember about sepsis for the exam?


Recognise organ dysfunction in the context of infection early, risk stratify using NEWS2/NICE criteria, and know the components and priorities of early management (oxygen, fluids, antibiotics, source control, escalation).


Are there must-know guidelines or scores related to sepsis?


Yes:

  • NICE suspected sepsis guidelines (NG253/254/255). (NICE)
  • Surviving Sepsis Campaign 2021 adult guidelines. (Lippincott Journals)
  • NEWS2 and local sepsis screening tools / UK Sepsis Trust red flag criteria. (The UK Sepsis Trust)


How many sepsis-related questions should I aim to do before the exam?


At least dozens, ideally 100+ dedicated sepsis/shock SBAs plus many more where sepsis is in the differential—enough that triage, recognition, and management become automatic thought patterns.


Key Takeaways: Sepsis & Septic Shock for FRCEM in 5 Bullet Points

  1. Define it properly: Sepsis = life-threatening organ dysfunction from infection; septic shock = sepsis + vasopressors for MAP ≥65 + lactate >2 despite fluids. (PMC)
  2. Risk-stratify early: Use NEWS2 and NICE risk criteria; treat red-flag, high-risk patients as time-critical. (NICE)
  3. Nail the first hour: Oxygen, IV access, bloods + lactate, appropriate fluids, early IV antibiotics, source control, and senior/ICU escalation. (Lippincott Journals)
  4. Avoid common traps: Don’t delay antibiotics in high-risk patients for imaging, don’t ignore lactate, and don’t over-treat low-risk cases with broad-spectrum “just in case.” (The UK Sepsis Trust)
  5. Practise, practise, practise: Use sepsis SBAs to hard-wire recognition and management patterns; then translate them into OSCE and real-life ED practice.


Ready to Test Yourself on Sepsis & Septic Shock?


Sepsis and septic shock are core FRCEM topics and a daily reality in EM:

  • Mastering them improves exam performance and real-world outcomes.
  • The fastest route is to combine pattern-recognition from SBAs with guideline-driven revision.