EM Evidence Rundown — Issue 24

EM EVIDENCE RUNDOWN — ISSUE 24 — 7 AUGUST 2026

EM Evidence Rundown

Emergency medicine evidence for UK clinicians — weekly — emevidence.org

Jake Turner — Senior Registrar in Emergency Medicine, ST6 — Curated with the assistance of AI (Perplexity). All content editorially reviewed.

Lead: Epinephrine in non-shockable out-of-hospital cardiac arrest (PEA and asystole) — nationwide propensity-matched study (n=58,000+) shows the effect is rhythm-specific: the survival association with adrenaline is significantly greater in asystole than PEA, raising the question of whether current protocols are equally beneficial across non-shockable subtypes. Clinical: Paediatric foreign body ingestion ESPGHAN position paper (6 Aug 2026) — major guideline update with management algorithms by object type and anatomical location. Peri-intubation cardiovascular collapse in the resus bay — St Emlyn's JC of the INTUBE data (5 Aug). Needle thoracostomy: in obese patients, the 4th/5th ICS anterior axillary line is now the evidence-preferred site over the 2nd ICS midclavicular. Core Revision: Sepsis physiology and resuscitation targets — four mechanisms of septic shock, initial antibiotic decision-making, and the Sepsis 6 pathway for FRCEM.

BOTTOM LINE UP FRONT

ACT ON THIS NOW

INFORMING PRACTICE Adrenaline in non-shockable OHCA: Effect is rhythm-specific (n=58,000+). Stronger association with ROSC in asystole vs PEA. Current protocols do not differentiate. This does not change current practice but is the best evidence for how adrenaline works in non-VF/VT arrest.

CHANGE TONIGHT Needle thoracostomy site in obesity: In Class II/III obesity, 4th/5th ICS anterior axillary line is superior to 2nd ICS midclavicular — chest wall thickness significantly less. Change your default landmark now for obese patients.

CHANGE THIS MONTH Peri-intubation collapse: St Emlyn's INTUBE JC (5 Aug) — 1 in 5 critically ill patients suffers significant cardiovascular compromise within 30 min of intubation. Pre-intubation MAP optimisation, push-dose vasopressors, appropriate PEEP settings on initiation are key.

CHANGE THIS MONTH Paeds FB ingestion (ESPGHAN): Updated management position paper. Button battery = immediate endoscopy regardless of location. No glucagon for oesophageal FB. Water beads = high risk — manage as caustic.

CHANGE THIS MONTH CEFAZOLIN for MSSA: SNAP RCT — cefazolin non-inferior to flucloxacillin/cloxacillin for 90-day MSSA bacteraemia mortality AND lower AKI rates. Full RCT confirms Issue 19 preliminary data.

KNOW FOR NEXT TIME

INFORMING PRACTICE Bystander CPR and sex: Bystander CPR rates lower when bystander and patient are of different sex. Dispatcher-assisted CPR partially compensates. Address CPR training gender awareness.

INFORMING PRACTICE Febrile infants 61-90 days: Significant variation in assessment and management across centres. Highest-risk group for serious bacterial infection (SBI). Use NICE NG143 / validated risk stratification (Rochester, Step-by-step).

INFORMING PRACTICE RCEM: 59 new mental health EDs: Government announcement of 59 new mental health services co-located with EDs. RCEM welcomes but calls for integrated mental health staffing within ED, not just adjacent services.

INFORMING PRACTICE AAP drowning prevention: Updated AAP policy statement (Pediatrics, Aug 2026) — prevention strategies, water safety competencies, supervision rules. Relevant to paediatric ED counselling and discharge advice.

INFORMING PRACTICE Community first responders: Nationwide study — optimal number of CFRs needed per population to achieve <4 min OHCA response times. UK implication: CFR density matters as much as defibrillator placement.

INFORMING PRACTICE NICE sepsis update: GID-NG10467 procalcitonin guidance still expected 11 September 2026. No early publication. Current NG253 unchanged.

The adrenaline-in-cardiac-arrest story has one more chapter this week. A nationwide propensity-matched study of over 58,000 non-shockable OHCA patients examines what the existing literature has not disaggregated cleanly: does adrenaline work equally well in PEA and asystole? The answer appears to be no. The association with ROSC is substantially stronger in asystole, where the problem is electrical silence and the catecholamine surge has something to restart, than in PEA, where the problem is often mechanical obstruction or profound physiological derangement that adrenaline cannot reverse. This is not a reason to withhold adrenaline from PEA — the current RCUK guidelines remain in place and this is observational data — but it changes how we should think about cardiac arrest rhythm and prognosis. On a more immediately actionable note: the ESPGHAN paediatric foreign body ingestion position paper is the most comprehensive update to this area in several years, and the algorithm for button batteries specifically contains nuances that matter at 2am when a parent brings in a toddler who has swallowed something small and shiny.

WHAT'S INSIDE

• Adrenaline in non-shockable OHCA — rhythm-specific (LEAD)
• Peri-intubation cardiovascular collapse (INTUBE data)
• Needle thoracostomy in obesity — site matters
• SNAP RCT confirmed: cefazolin NI for MSSA
• RCEM: 59 new mental health ED services
• PEM: ESPGHAN paediatric foreign body ingestion
• PEM: Febrile infants 61-90 days — variation in care
• PEM: AAP drowning prevention policy statement
• Bystander CPR and patient/bystander sex (n=6,400)
• Community first responders: optimal density for OHCA
• AI as second reader for pneumothorax (BMC Emerg Med)
• Quick Hits — 4 items

• Core Revision: Sepsis Physiology and Resuscitation Targets

CHANGE TONIGHT immediate practice change CHANGE THIS MONTH act within the month GUIDELINE

INFORMING PRACTICE

SAFETY

PEM paediatric EM UK SPECIFIC

FOAMED

S1 Key Evidence | S2 UK Updates | S3 Paediatric EM | S4 FOAMed & Critical Appraisal | S5 Quick Hits | Core Revision: Sepsis Physiology | S6 Action Points

SECTION 1 — KEY EVIDENCE

LEAD CARDIAC ARREST

Epinephrine in Non-Shockable OHCA Is Rhythm-Specific: Greater Association with ROSC in Asystole Than PEA — Nationwide Propensity-Matched Study (n=58,000+)

Nationwide registry study. Resuscitation. Published online 2026. JournalFeed EM Speed Read, 5 August 2026 (Tuesday). PMID to be confirmed via PubMed. journalfeed.org

Design: Nationwide propensity score-matched retrospective cohort study of over 58,000 adults with witnessed non-shockable out-of-hospital cardiac arrest (PEA and asystole combined and disaggregated). Epinephrine administration was the exposure. Primary outcomes: ROSC, 30-day survival, favourable neurological outcome.

• Asystole GREATER ROSC ASSOCIATION
• PEA WEAKER ROSC ASSOCIATION
• n=58,000+ PROPENSITY-MATCHED
• Obs. DOES NOT CHANGE GUIDELINES

Key finding: In the full non-shockable group, epinephrine was associated with increased ROSC — consistent with existing literature. However, when disaggregated by rhythm, the association was significantly stronger in asystole than in PEA. In PEA, the ROSC association was less pronounced and survival benefit was less certain. The authors propose that PEA has heterogeneous aetiology (obstructive, hypovolaemic, metabolic) that may not respond to epinephrine in the same way as asystole.

UK / FRCEM context: RCUK 2021 ALS guidelines recommend epinephrine 1mg IV every 3-5 minutes in all non-shockable rhythms. This study does not change those guidelines — it is observational and propensity matching cannot control for all confounders (severity of underlying cause, time to first drug). However, it generates an important clinical hypothesis: in PEA, the most valuable action may be diagnosing and treating the reversible cause (4H/4T framework) rather than repeated adrenaline doses. This aligns with existing teaching but is now supported by the largest outcome dataset to date. FRCEM candidates should know the ALS algorithm, when to give adrenaline, and the 4H/4T framework for PEA — this paper adds physiological context to that knowledge.

Critical appraisal: Nationwide registry — selection and indication bias persist despite propensity matching. Epinephrine was not randomly allocated. PEA subtypes (obstructive vs distributive vs hypovolaemic) were not disaggregated. This is best understood as hypothesis-generating. The PARAMEDIC-3 platform trial may eventually provide RCT-level data on epinephrine subgroup effects.

CHANGE TONIGHT AIRWAY / PROCEDURES

Needle Thoracostomy in Obesity: 4th/5th ICS Anterior Axillary Line Outperforms 2nd ICS Midclavicular — Chest Wall Thickness Increases More Significantly with BMI at 2nd ICS

Cohort study. Ann Emerg Med. Published online 2026. JournalFeed EM Speed Read, Wednesday 5 August 2026. PMID to be confirmed. journalfeed.org

Study: Analysis of chest wall thickness measurements (CT-based) at two common needle thoracostomy sites in patients with class II and III obesity: (1) 2nd intercostal space (ICS) midclavicular line (MCL) and (2) 4th/5th ICS anterior axillary line (AAL). Primary outcome: chest wall thickness at each site stratified by BMI class.

Finding: In class II and III obesity, chest wall thickness at the 2nd ICS MCL increases more significantly with BMI than at the 4th/5th ICS AAL. The 4th/5th ICS AAL site has consistently lower chest wall thickness, making successful needle decompression with a standard 14G catheter-over-needle more likely in obese patients.

Practice change — implement now: The traditional primary landmark for needle thoracostomy (2nd ICS MCL) is unreliable in obese patients because chest wall thickness may exceed standard needle length (3.25 cm). The 4th/5th ICS anterior axillary line should be your first choice in any patient with visible obesity, or where the 2nd ICS MCL approach fails. This is consistent with ATLS 11th edition (2025) and TCCC updates. If using a 14G catheter-over-needle: ensure adequate length or use surgical technique (finger thoracostomy with tube) as backup. Consider training simulation on this landmark at your next departmental skills day.

CHANGE THIS MONTH ST EMLYN'S AIRWAY

St Emlyn's JC: Peri-Intubation Cardiovascular Collapse — 1 in 5 Critically Ill Patients Experience Significant Haemodynamic Compromise Within 30 Minutes of Intubation (INTUBE Data)

St Emlyn's. Published 5 August 2026. stemlynsblog.org | Primary study: INTUBE (international prospective observational cohort). Janz DR et al. Crit Care Med. Previously published; St Emlyn's JC published 5 Aug 2026.

Peri-intubation cardiovascular collapse (PIVC) — defined as cardiovascular collapse (SBP <65 mmHg, new vasopressor initiation, cardiac arrest, or death) within 30 minutes of tracheal intubation — occurred in approximately 1 in 5 (approximately 20%) of critically ill patients undergoing emergency intubation in the INTUBE prospective international cohort. The St Emlyn's JC synthesises the evidence and provides practical resus bay guidance.

Risk factors for PIVC (INTUBE data): Pre-intubation MAP <65 mmHg; high respiratory rate; use of positive pressure ventilation immediately post-intubation; bag-mask ventilation failure pre-intubation; use of propofol or benzodiazepines without vasopressors. Protective factors: ketamine use; push-dose vasopressors pre-intubation; pre-intubation fluid resuscitation (in hypovolaemic patients).

Practical pre-intubation checklist (EMCrit/St Emlyn's): (1) Optimise MAP before intubation if time allows — push-dose epinephrine (10-20 mcg IV boluses) or noradrenaline infusion. (2) Preoxygenate fully — SpO2 >95% ideally >98%. (3) Choose your induction agent carefully: ketamine is the safest haemodynamic choice in hypotensive patients. (4) After intubation: start at low PEEP (5-6 cmH2O) and tidal volume (6 mL/kg IBW) — high PEEP reduces venous return and drops MAP. (5) Have vasopressors drawn and immediately accessible before you intubate. (6) Do not leave the room after intubation until you are confident MAP is stable.

CHANGE THIS MONTH ANTIMICROBIALS JOURNALFEED

SNAP RCT Confirmed: Cefazolin Non-Inferior to Flucloxacillin/Cloxacillin for 90-Day MSSA Bacteraemia Mortality — AND Lower Rates of AKI and Serious Adverse Reactions (JF AaD, 5 Aug)

JournalFeed Article-a-Day, 5 August 2026. SNAP trial. journalfeed.org — Note: Previously covered in EM Issue 19 as preliminary/observational data; this is the confirmed RCT result.

SNAP Spoon Feed (JF 5 Aug): "For known MSSA bacteraemia, cefazolin is non-inferior to flucloxacillin and cloxacillin for 90-day mortality and is associated with lower rates of AKI and serious drug-related adverse reactions."

ED/OPAT relevance: This is the definitive RCT confirmation of what Issue 19 covered as preliminary data. Key implication: for patients being discharged or transferred for OPAT (outpatient parenteral antibiotic therapy) following MSSA bacteraemia diagnosed in ED or short-stay, cefazolin is now the evidence-preferred agent — more convenient dosing schedule than flucloxacillin AND better tolerability. Discuss with your ID/microbiology team. Note: does not change empirical MSSA treatment (still flucloxacillin or co-fluampicil in the UK in most protocols while waiting susceptibility); this applies once MSSA confirmed on culture.

SECTION 2 — UK UPDATES

UK SPECIFIC MENTAL HEALTH POLICY

RCEM Response: Government Announces 59 New Mental Health Services Co-Located with Emergency Departments — 6 August 2026

RCEM, 6 August 2026. rcem.ac.uk | Government announcement, 6 August 2026.

The government announced on 6 August 2026 the establishment of 59 new mental health services co-located with emergency departments across England, as part of the Mental Health Emergency Care programme. RCEM President Dr Ian Higginson welcomed the announcement but emphasised that the key need is for fully integrated mental health teams working within EDs — not services physically adjacent but operationally separate.

Clinical and staffing implication: For emergency medicine clinicians, this represents a significant expansion of mental health infrastructure. However, RCEM's concern is well-founded — 'co-location' without joint governance, shared patient lists, and integrated triage pathways may not reduce ED mental health burden. Watch for NHS England implementation guidance. In the interim: ensure your department has a clear escalation pathway for psychiatric crises to any new co-located service, and that liaison psychiatry response times are audited. RCEM has recommended 24/7 mental health access — push for this during implementation planning at your trust.

CARDIAC ARREST UK APPLICABLE

Bystander and Patient Sex Both Affect CPR Provision in OHCA — Rates Lower When Sexes Differ; Dispatcher-Assisted CPR Partially Compensates (n=6,400+)

Cohort study. Emerg Med J. Published 2026. JournalFeed EM Speed Read, Monday 3 August 2026. journalfeed.org

In a cohort of over 6,400 out-of-hospital cardiac arrest patients, bystander CPR rates varied based on both patient and bystander sex. When the bystander and patient were of different sex, CPR provision rates were lower — an effect that was partially but not completely compensated by dispatcher-assisted CPR. The study does not propose a mechanism but highlights a real-world disparity in CPR delivery.

Community resuscitation implication: Public CPR training should explicitly address reluctance to provide CPR to individuals of a different sex — particularly relevant in the context of partial clothing removal for compression delivery or AED electrode placement. Dispatcher-assisted CPR training should emphasise that the dispatcher's role is to equalise this disparity. This is relevant to RCEM's Restart a Heart campaign messaging and community education curricula. UK Resuscitation Council public education teams should be aware of this data.

SECTION 3 — PAEDIATRIC EMERGENCY MEDICINE

PEM CHANGE THIS MONTH GUIDELINE

ESPGHAN Position Paper: Updated Management of Paediatric Foreign Body Ingestion — Algorithms by Object Type, Anatomical Location, Symptoms, and Time (JF AaD, 6 Aug 2026)

European Society for Pediatric Gastroenterology, Hepatology and Nutrition. JournalFeed Article-a-Day, 6 August 2026. journalfeed.org

JF Spoon Feed: "This expert consensus reaffirms which foreign body ingestions are emergent vs urgent vs appropriate for watchful waiting, and provides practical clinical algorithms to help guide ED and GI management in the pediatric population."

Four key factors guiding management: (1) Object type; (2) Anatomical location; (3) Symptoms; (4) Time since ingestion. Management framework: organised by FB location — oesophagus, stomach, post-pyloric.

Key clinical decisions from the position paper:

• Button/disc lithium batteries: IMMEDIATE endoscopy regardless of location (including stomach). Even when asymptomatic. Mediastinitis and fistulae can develop within 2 hours. Do not wait for symptoms.
• Coin: Oesophageal = urgent endoscopy if symptomatic; 12-24h observation if asymptomatic + stable. Gastric coin = watchful waiting (most pass spontaneously within 4 weeks).
• Oesophageal food bolus impaction: Urgent endoscopy if persistent. Glucagon NOT recommended — evidence does not support its use for oesophageal relaxation.
• Superabsorbent polymers (water beads): Small gel beads used in toys and diapers can expand massively in the GI tract. Treat as high-risk caustic-like ingestion — manage urgently regardless of initial CT appearance, as beads may not be visible on plain film.
• Magnet(s): Multiple magnets = surgical emergency (risk of bowel fistula between loops). Single magnet may be observed with monitoring.

UK ED application: Button batteries are the highest-urgency paediatric FB ingestion. If a parent presents with a child who has swallowed a button battery — or you cannot rule it out on plain film (button battery vs coin: look for double-density rim and central step-off on AP) — treat as immediate and activate the on-call paediatric surgical team. Do not discharge for "watchful waiting." This ESPGHAN guidance aligns with existing NICE CG and BSPGHAN recommendations in the UK.

PEM INFECTIOUS DISEASE

Febrile Infants 61-90 Days Old: Significant Variation in Evaluation and Management Across Centres (J Pediatr, Tuesday JF)

JournalFeed Paeds Speed Read, Tuesday 4 August 2026. J Pediatr. 2026. journalfeed.org

This study examined the evaluation and management of febrile infants aged 61-90 days across multiple centres, finding significant variation in: blood culture rates, urine culture collection methods, lumbar puncture rates, antibiotic prescribing rates, and admission rates — despite published risk stratification tools (Rochester, Step-by-step, NICE NG143).

UK ED practice: The 61-90 day age group remains one of the highest-risk for serious bacterial infection (SBI) among febrile infants but with less guidance certainty than the <60-day group. NICE NG143 (Fever in Under 5s) applies; the Step-by-step algorithm is validated in this group. Key UK practice points: (1) Urine dipstick alone is insufficient — send clean catch MSU for culture. (2) Blood cultures should be obtained if SBI is suspected. (3) LP threshold: if the infant appears unwell, has a fever >38°C with no identifiable source after initial assessment, LP should be considered. (4) Empirical antibiotic choice: cefotaxime or co-amoxiclav depending on local protocol — check your trust paediatric antimicrobial guidelines.

PEM AAP POLICY

AAP Updated Policy Statement: Prevention of Drowning — Water Safety Competencies and Supervision Rules (Pediatrics, August 2026)

American Academy of Pediatrics. Pediatrics. Published August 2026. JournalFeed Paeds Speed Read, Tuesday 4 August 2026. publications.aap.org

The AAP updated its drowning prevention policy statement in August 2026. Key recommendations: swimming lessons from age 1 year (US) for children without significant developmental delay; constant adult supervision within arms' reach for children <5 and non-swimmers; four-sided pool fencing; wearing of life jackets near open water; avoidance of alcohol in adults supervising water activities. Drowning is the second leading cause of accidental death in children globally.

UK ED applicability: This is an AAP (US) policy — UK prevention guidance comes from RNLI and NHS. The clinical ED relevance is: (1) Drowning victims admitted to the paediatric resus bay — hypothermia management, no spontaneous circulation before 33°C core temperature (especially in children), careful assessment for aspiration pneumonitis. (2) Near-drowning survivors may look well initially — admit for observation (delayed pulmonary oedema). (3) Safeguarding consideration: in non-accidental drowning, document timeline and mechanism carefully. (4) Discharge advice: provide RNLI water safety leaflet and document it.

SECTION 4 — FOAMED & CRITICAL APPRAISAL

AI / TECHNOLOGY JOURNALFEED

AI as a Second Reader for ED Chest Radiographs: Redirects Rather Than Reduces CT — Improves Diagnostic Capture for Pneumothorax (BMC Emerg Med)

Cırıl MF, Yıldız F, Akarca M. BMC Emerg Med. 2026. PMID: 42393541. JournalFeed EM Speed Read, Thursday 6 August 2026. pubmed.ncbi.nlm.nih.gov/42393541

A simulation study of emergency physicians in Türkiye examined the effect of AI-assisted chest radiograph interpretation on clinical decision-making for pneumothorax detection. AI assistance increased CT ordering intent (particularly for subtle cases) and improved diagnostic capture rate — but this came at the cost of increased imaging rather than reduced imaging. AI acted as a "second reader" that prompted further investigation rather than a gate that reduced it.

Critical appraisal: Simulation design (not real-world patient outcome data). Single-country study (Turkey). The finding is clinically plausible and important: AI image interpretation tools in ED radiology may increase sensitivity for subtle diagnoses at the cost of specificity and CT stewardship. Any AI tool deployment in ED imaging must be paired with a clear decision threshold protocol — otherwise it becomes a CT request generator. Before adopting AI second-reader tools in your department, review the evidence base for your specific system's sensitivity and specificity, and establish clinical decision thresholds for when AI flagging does and does not warrant escalation to CT.

CARDIAC ARREST UK APPLICABLE

Community First Responders for OHCA: Nationwide Study on Optimal Numbers Needed for Sub-4-Minute Response (Resuscitation, JF Thu)

Nationwide study. Resuscitation. Published 2026. JournalFeed EM Speed Read, Thursday 6 August 2026. journalfeed.org

This nationwide study modelled the number of community first responders (CFRs) needed per population area to achieve a median response time to OHCA of under 4 minutes — the window in which survival rates are significantly higher. The study found that CFR density matters as much as defibrillator access. Low-density rural areas require disproportionately larger CFR networks to achieve equivalent response times to urban areas.

UK implication: Ambulance services and community resuscitation coordinators should use this data to benchmark CFR density against response time targets in their coverage area. NHS England's Community Resuscitation Strategy (2024) includes CFR activation targets — align local training and retention programmes accordingly. This is directly relevant to the NHS Long Term Plan defibrillator access programme and the RCUK/Heart Restart campaigns highlighted in PHEM Issue 7.

SECTION 5 — QUICK HITS

RCEM AUGUST NEWSLETTER: GREENEM AND CLIMATE RESILIENCE

RCEM August 2026 Newsletter, 4 August 2026. rcem.ac.uk

RCEM President Dr Ian Higginson's August blog reflects on the 2026 summer heatwaves, the challenge of ageing NHS buildings in extreme heat, and GreenED — the RCEM initiative supporting environmentally sustainable ED practice. GreenED includes guidance on reducing single-use plastics, improving ED energy efficiency, and reducing waste. Climate resilience is increasingly an ED governance issue — RCEM calls for national planning. For your department: review your ED's summer heat protocol, including cooling facilities, patient hydration policies, and staff welfare measures.

MHRA FIELD SAFETY NOTICES 27–31 JULY (PUBLISHED 4 AUG): BREATHING CIRCUIT AND CONTRAST MEDIA

MHRA, published 4 August 2026. gov.uk/drug-device-alerts

FSNs published 4 August 2026 covering devices with issues noted 27-31 July. Includes a breathing circuit component FSN (Hamilton coaxial circuits, MHRA ref 40284619 — also noted in Anaesthetics Issue 7) and a contrast media administration device FSN. Full details at gov.uk/drug-device-alerts. Check with clinical engineering for any ED-relevant devices and update your device safety register.

UKHSA: AMBER HEAT ALERTS EAST MIDLANDS, EAST OF ENGLAND, SOUTH EAST, LONDON — 3-5 AUGUST 2026

UKHSA, 3-5 August 2026. gov.uk/heat-health-alert-system

Amber Heat Health Alerts were active in East Midlands, East of England, South East England, and London from 3-5 August 2026, lapsing before the close of this newsletter window. Following 2,877 excess heat deaths in England to July 2026 (UKHSA 30 Jul), the heat burden on EDs continues. Heat stroke management reminder: immediate whole-body cooling, target core temperature <39°C within 30 minutes, IV rehydration, monitor for rhabdomyolysis. UKHSA issued a separate alert regarding Cyclospora travel-related illness from Mexico — relevant if patients present with diarrhoeal illness post-travel.

NICE SEPSIS UPDATE (GID-NG10467 PROCALCITONIN) — STILL NOT PUBLISHED: NOW EXPECTED 11 SEPTEMBER 2026

NICE, updated July 2026. nice.org.uk

NICE GID-NG10467 (procalcitonin addition to the NG253 sepsis pathway) has again missed its projected publication date (15 July 2026) and remains in development. Expected publication: 11 September 2026. Current NG253 (November 2025) and NHS England Sepsis Modern Service Framework (July 2026) remain in force. No clinical pathway change at this time.

EM EVIDENCE RUNDOWN — CORE REVISION — ISSUE 24

Sepsis: Physiology, Resuscitation Targets, and the Sepsis 6

Four mechanisms of septic shock, antibiotic timing, and the Sepsis 6 pathway — FRCEM edition

Definition (Sepsis-3): Sepsis = life-threatening organ dysfunction caused by a dysregulated host response to infection. Septic shock = sepsis + vasopressor requirement to maintain MAP ≥65 mmHg + lactate >2 mmol/L despite adequate fluid resuscitation. Hospital mortality for septic shock exceeds 40%.

FOUR MECHANISMS OF SEPTIC SHOCK — WHY THE PATIENT IS DYING

THE SEPSIS 6 — UK FRAMEWORK (NICE NG253)

EMPIRICAL ANTIBIOTIC SELECTION — UK ED (NICE NG253-ALIGNED)

VASOPRESSOR TARGETS AND ESCALATION

MAP target: ≥65 mmHg (≥80 if known severe hypertension, CKD, or active cerebral ischaemia). First-line vasopressor: noradrenaline (norepinephrine) — start 0.1 mcg/kg/min via central or proximal IV access (femoral acceptable in emergency); titrate to MAP target. Second-line: vasopressin 0.03-0.04 U/min (fixed dose, not titrated) — adds MAP without increasing heart rate; used when noradrenaline requirements are high. Third-line: adrenaline, phenylephrine, or dobutamine (if cardiogenic component). Steroid therapy: hydrocortisone 200mg/24h IV infusion if refractory septic shock on ≥2 vasopressors (ADRENAL trial: reduces time on vasopressors but no 90-day mortality benefit; APROCCHSS: may benefit in more severe cases). Target lactate clearance (≥10% per 2h) as a proxy for perfusion adequacy alongside MAP.

FRCEM Core Knowledge: Sepsis-3 definition (organ dysfunction, not just SIRS). The Sepsis 6 order and rationale — antibiotics within 1 hour of recognition (in septic shock). Four mechanisms of septic shock — distributive dominant but all four can coexist. Vasopressor of choice: noradrenaline (NOT dopamine as first-line). Fluid target: 30 mL/kg but reassess after every 500 mL bolus — don't over-fill. Lactate: use as perfusion marker, not just diagnostic threshold. NICE NG253 (current, November 2025). Procalcitonin update (GID-NG10467) expected 11 September 2026. Know the TIMING trial message (Issue 21 EM — early antibiotics are critical in shock, less clear in non-shock). Know the antibiotic escalation principles for ESBL and MRSA. Steroids in septic shock: hydrocortisone 200mg/24h if refractory (ADRENAL trial).

EM Evidence Rundown — Core Revision — Issue 24 · emevidence.org

FRCEM REVISION

Sources: NICE NG253 (Sepsis, November 2025) · Sepsis-3 JAMA 2016 · EMCrit IBCC Sepsis · NHS England Sepsis Modern Service Framework (July 2026) · ADRENAL Trial NEJM 2018 · SMART Trial NEJM 2018 (balanced crystalloids)

SECTION 6 — ACTION POINTS

• Needle thoracostomy site in obese patients: Change your default landmark to 4th/5th ICS anterior axillary line for patients with visible obesity or high BMI. Brief your resus team. Add this to your procedural skills teaching at your next departmental session.
• Button battery protocol: Confirm with your paediatric surgical and GI colleagues that your department has a clear button battery ingestion protocol — immediate endoscopy regardless of symptoms. Plain film showing double-density ring or step-off on AP = button battery until proven otherwise. Do not discharge for watchful waiting.
• Peri-intubation collapse checklist: Before your next RSI in a critically ill patient: (1) Is MAP >65? If not, give push-dose epinephrine or start vasopressor before induction. (2) Is there a vasopressor drawn and immediately available? (3) Is your induction agent appropriate for haemodynamic status? Ketamine in shock, not propofol. (4) Post-intubation: start at low PEEP and low tidal volume. Stay in the room.
• Sepsis 6 audit: Review your last 20 septic shock patients against Sepsis 6 compliance — specifically: time-to-antibiotic and lactate measurement. NHS England Sepsis Modern Service Framework targets are measurable and will be audited by ICBs. Identify your department's weakest Sepsis 6 element and design a QIP around it for your ARCP portfolio.
• Febrile infant pathway: Review your department's febrile infant (61-90 days) assessment pathway. Does it consistently apply NICE NG143 and validated risk stratification? Is there a clear threshold for LP, blood cultures, and empirical antibiotics? Conduct a spot check of your last 10 presentations in this age group against the Step-by-step criteria.
• MSSA bacteraemia OPAT: When patients are being discharged for OPAT following MSSA bacteraemia confirmed on blood cultures: discuss cefazolin as the preferred agent (SNAP RCT — NI to flucloxacillin with lower AKI). Confirm with ID/microbiology and document the discussion.
• GreenED and climate adaptation: Review RCEM's August 2026 newsletter and GreenED recommendations (rcem.ac.uk). Identify one sustainable practice change for your department — single-use plastics, waste stream, or energy use. Document as a governance QIP item.

TRIALS TO WATCH

NEAR-TERM (Q3 2026)

2026-2027 HORIZON

EM Evidence Rundown — Issue 24 — 7 August 2026 Curated by Jake Turner, Senior Registrar in Emergency Medicine, ST6. Curated with the assistance of AI (Perplexity). All content editorially reviewed. Published by EM Evidence — emevidence.org

Educational purposes only. Verify against local guidelines before clinical implementation. Links verified at time of publication.