EM Evidence Rundown — Issue 18

EM Evidence Rundown

Emergency Medicine — UK Edition | Weekly | Thursday

Issue 18 | 25 June 2026 | emevidence.org

Jake Turner

Curated with the assistance of AI (Perplexity). All content editorially reviewed.

BIHCA (JAMA): Bicarbonate in cardiac arrest — no benefit (n=779). MARCH (NEJM): Carbocisteine and hypertonic saline — no benefit, causes harm (n=1956). Stop both routinely. CHANGE THIS MONTH: BIHCA (stop bicarb in cardiac arrest) | MARCH (stop mucoactive agents in ventilated patients) | UKHSA Red Heat Alert — active now | Measles 801 cases, 2 child deaths

BLUF — BOTTOM LINE UP FRONT

ACT ON THIS NOW

• CHANGE THIS MONTH Cardiac arrest bicarb

(BIHCA, JAMA): No benefit on ROSC, alkalosis 35%, hypernatraemia 42%. Do NOT give bicarbonate routinely during cardiac arrest.

• CHANGE THIS MONTH Ventilated patients

(MARCH, NEJM): Stop carbocisteine (GI bleed RR 6.5) and hypertonic saline (bronchoconstriction RR 5.7) routinely. Useless and harmful.

• CHANGE TONIGHT Heat alert (UKHSA Red, 6

regions): Heat stroke = cool immediately to 39°C, no investigations first. Check lithium, digoxin, electrolytes in every elderly/exertional heat presentation. See alert.

• CHANGE TONIGHT Measles (UKHSA, 25 June):

801 cases, 2 child deaths. England loses WHO elimination status. Airborne precautions from triage. Notifiable within 24h. See update.

• CHANGE TONIGHT MenB university programme

(opens 20 July): Largest-ever MenB outbreak in Kent preceded announcement. Low LP threshold in all young adults with any meningism. See update.

KNOW FOR NEXT TIME

• CHANGE THIS MONTH Bicarb in metabolic

acidosis (SODa-BIC): No reduction in MAKE30. Only consider: pH ≤7.2 + AKI Stage 2-3 + vasopressors (SSC 2026 conditional). See synthesis.

• CHANGE THIS MONTH Paediatric sepsis bolus

(ADC, n=5352): Bolus >55ml/kg: OR 20.5 mortality. Small boluses 10-20ml/kg, reassess after each. See item.

• CHANGE THIS MONTH ANDROMEDA-SHOCK-2

(JAMA): CRT-guided resuscitation superior to lactate-alone in septic shock. Check CRT after every fluid/vasopressor intervention. See item.

• GUIDELINE WATCH ICS SOA26 (30 June – 2 July,

ICC Birmingham): BICARICU-2 full results + ANDROMEDA-SHOCK-2 deep-dive expected. Issue 19 will cover outputs. See preview.

• INFORMING PRACTICE Low back pain (JAMA,

Cashin et al): 90% nonspecific, imaging NOT indicated for uncomplicated LBP. NSAIDs first-line; opioids not first-line; bed rest harmful. See item.

• PAEDS ICS SOA26 paeds fluids: Two independent studies now show more bolus fluid = worse outcomes in children with sepsis. Be very conservative with bolus

volumes. See item.

SECTION 1 — KEY TRIALS & ARTICLES

Granfeldt A, Kirkegaard BL, Vallentin MF et al. JAMA. Published online 11 June 2026. doi:10.1001/jama.2026.10628. PMID: 42273960

BIHCA — Bicarbonate for In-Hospital Cardiac Arrest: A Randomised Clinical Trial

CHANGE THIS MONTH RCT FRCEM

• RR 1.05 SUSTAINED ROSC (95%CI 0.88–1.24)
• 35% vs 20% ALKALOSIS BICARB VS PLACEBO
• 42% vs 29% HYPERNATRAEMIA BICARB VS PLACEBO
• n=779 21 HOSPITALS DENMARK

Design: Double-blind, placebo-controlled, parallel-group, superiority RCT. 21 hospitals, Denmark. Feb 2023–Feb 2026.

Population: Adults with in-hospital cardiac arrest who had received at least 1 dose of adrenaline. n=779 eligible for primary analysis (median age 73, 64% male).

Intervention: Sodium bicarbonate 50mmol IV as soon as possible after first adrenaline, then repeated once after second adrenaline if still in arrest (max 100mmol total) vs matched placebo.

Primary outcome: Sustained ROSC (≥20 minutes)

Primary result: 146/372 (39%) bicarb vs 150/407 (37%) placebo. Adjusted RR 1.05 (95%CI 0.88–1.24), p=0.62. NO BENEFIT.

*Hierarchical testing stopped after the primary endpoint was not met; these outcomes were not formally powered.

Safety alert: Sodium bicarbonate causes biochemical harm (alkalosis 35%, hypernatraemia 42%) without improving ROSC. Remove it from routine cardiac arrest protocols immediately. EXCEPTIONS remain valid and mechanistically justified: hyperkalaemia arrest (give bicarb), TCA/sodium-channel blocker toxicity (give bicarb), cocaine-associated cardiac arrest. These indications are unaffected by BIHCA.

Critical appraisal: Single country (Denmark), 21 hospitals. Median time to drug was 8 minutes — fast and well-executed. Endpoint (sustained ROSC ≥20 min) is appropriate but does not test neurological recovery. 30-day mortality numerically favoured bicarb (12% vs 9.1%, RR 1.25) but the trial was neither powered nor structured to test this — it is a signal to monitor, not a reason to give bicarb. Critically, the dose of bicarb did NOT normalise pH in most patients — suggesting the acidosis-correction hypothesis itself may be flawed, not just underdosed.

Why it matters: Sodium bicarbonate is used in more than 50% of in-hospital cardiac arrests in many countries. BIHCA provides the clearest evidence to date that this is futile for ROSC and biochemically harmful. RCUK 2025 guidelines and AHA 2025 already state routine bicarb is not recommended (Class III), but many UK ED teams continue the practice. BIHCA now provides Level I RCT evidence. Tell your resus lead today: remove bicarb from routine cardiac arrest protocols. Keep it labelled and available for hyperkalaemia arrests, TCA toxicity, and sodium-channel blocker overdose.

Tell your department: "We have definitive trial evidence (BIHCA, JAMA 2026, n=779) that sodium bicarbonate during cardiac arrest does not improve ROSC and causes alkalosis and hypernatraemia. Stop giving it routinely. Exceptions: hyperkalaemia, TCA overdose, sodium-channel blocker toxicity."

MARCH Trial Investigators (NIHR-funded, multicentre RCT). N Engl J Med. Published 10 June 2026. PMID: 42267821

MARCH — Carbocisteine and Hypertonic Saline for Acute Respiratory Failure in ICU: No Benefit, Causes Harm

CHANGE THIS MONTH RCT FRCEM

• HR 0.96 MV DURATION CARBOCISTEINE (NS)
• RR 6.51 GI BLEED CARBOCISTEINE
• RR 5.73 BRONCHOCONSTRICTION HTS
• n=1956 2×2 FACTORIAL NIHR-FUNDED

Design: 2×2 factorial RCT, 1,956 participants, multiple UK ICUs. Four arms: carbocisteine alone, hypertonic saline (HTS) alone, both, usual care.

Population: Critically ill mechanically ventilated adults with acute respiratory failure and difficult-to-clear secretions.

Primary outcome: Duration of mechanical ventilation

Safety alert: Both carbocisteine and hypertonic saline should be stopped as routine practice in ventilated patients with acute respiratory failure. Carbocisteine carries a 6.5-fold increase in clinically important upper GI bleeding. HTS causes bronchoconstriction (RR 5.73) and hypoxaemia (RR 13.29) during nebulisation. Neither agent reduces mechanical ventilation duration.

Critical appraisal: NIHR-funded (directly UK-relevant), well-powered at n=1,956, factorial design allowing two treatments to be tested simultaneously. No blinding for patients/clinicians but the primary outcome (duration of mechanical ventilation) is objective and difficult to manipulate. The carbocisteine GI bleed signal is small in absolute terms (1.4% vs 0.2%) but a 6.5-fold relative increase is clinically and statistically meaningful. The HTS hypoxaemia signal (RR 13.29) is the most alarming finding — immediate clinical relevance for patients already compromised by respiratory failure.

Why it matters: Carbocisteine is prescribed in UK EDs for COPD exacerbations and bronchiectasis. HTS nebulisers are routinely used in UK ICUs and often started in EDs. MARCH now provides definitive evidence that neither agent shortens ventilation, and both cause harm. This should stop routine prescribing immediately. Discuss with your ICU pharmacist and intensivists. Also review your COPD/bronchiectasis discharge prescribing — does carbocisteine have a role in non-ventilated outpatients? MARCH does not directly address this, but raises questions about the broader mucoactive class.

Tell your department: "MARCH (NEJM 2026, n=1956): carbocisteine in ventilated patients causes GI bleeds (6× increase), and hypertonic saline nebulisers cause bronchoconstriction and hypoxaemia. Neither shortens ventilation. Stop both routinely. Feed back to your ICU team and pharmacist."

SODa-BIC RCT: JAMA (equivalent). Published 12 June 2026. PMID: 42283370. n=500, 55 ICUs, 7 countries. | Chen JJ et al. Meta-analysis. Crit Care Med. 2026. PMID: 42171427. 4 RCTs, n=1111.

SODa-BIC + Bicarbonate Meta-Analysis — The "Bicarb Reflex" Dismantled

INFORMING PRACTICE RCT + META-ANALYSIS FRCEM

• +1.2% MAKE30 ADJ DIFF (NS, P=0.78)
• RR 0.69 RRT REDUCTION (META-ANALYSIS)
• RR 0.84 MORTALITY (NS; BAYESIAN 90.4%)
• n=500 SODA-BIC 55 ICUS, 7 COUNTRIES

SODa-BIC RCT: Adults with metabolic acidosis on vasopressors in ICU. Primary outcome: MAKE30 (major adverse kidney event at 30 days).

MAKE30: 40.2% bicarb vs 39.4% control (adjusted diff +1.2%, 95%CI -7.1 to +9.4, p=0.78) — no benefit. RRT use: 16.8% vs 20.9% (adjusted diff -3.9%, NS). In-hospital mortality day 30: 25.4% vs 24.0% (NS). 4 adverse events in bicarb arm vs 0 in placebo (p=0.06).

Meta-analysis (Chen JJ, 4 RCTs, n=1,111): Bicarb significantly reduced RRT requirement (RR 0.69, 95%CI 0.61–0.78). Mortality: trend only (RR 0.84, NS). Bayesian analysis: 90.4% probability of any mortality reduction; 94.6% probability of RRT reduction.

UK synthesis — when IS bicarbonate indicated in the ED? (1) Hyperkalaemia with metabolic acidosis — use it (temporising measure) (2) TCA/sodium-channel blocker overdose (flecainide, cocaine) — mechanistic rationale, use it (3) Severe DKA with pH <6.9 — consider (controversial; insulin + fluids first; seek ICU input) (4) Severe lactic acidosis: pH ≤7.2 + AKI Stage 2-3 + vasopressors — SSC 2026 conditional recommendation; discuss with ICU Do NOT give bicarb just to improve VBG numbers. The acidosis-correction hypothesis is now under serious challenge across three simultaneous June 2026 trials (BIHCA, MARCH, SODa-BIC).

Why it matters: Three major trials published within days of each other in June 2026 all challenge reflexive bicarbonate use — in cardiac arrest (BIHCA), in ICU respiratory failure (MARCH), and now in metabolic acidosis/vasopressor shock (SODa-BIC). The meta-analysis provides reassurance that bicarb may still reduce RRT requirement in severe acidosis, and the SSC 2026 conditional recommendation for pH ≤7.2 + AKI 2-3 remains valid. But the era of giving bicarb to "correct" any acidosis on a VBG is over.

Hernandez G, Ospina-Tascon GA et al. JAMA. Published October 2025. Presented CCR26 Belfast 11 June 2026 and ICS SOA26 (30 June – 2 July 2026).

ANDROMEDA-SHOCK-2 — Capillary Refill Time vs Lactate as Resuscitation Endpoint in Septic Shock

CHANGE THIS MONTH RCT FRCEM

• Superior CRT COMPOSITE ENDPOINT
• ~43% 28-DAY MORTALITY (BOTH ARMS, IDENTICAL)
• −250mL LESS FLUID CRT ARM (FIRST 8H)
• 31 ICUs 9 COUNTRIES MULTICENTRE RCT

Design: RCT, 31 ICUs, 9 countries. Adults with septic shock. Arms: CRT-guided resuscitation (target CRT ≤3s, titrating fluids/vasopressors to CRT) vs lactate-guided (target lactate clearance ≥10% per 2h).

Results: CRT group superior on composite organ support endpoint. 28-day mortality identical between groups (~43%, NS). CRT group received 250mL less fluid in first 8h and started vasopressors earlier.

Why it matters: CRT is universally available in any ED — no laboratory required, no delay. It responds more rapidly to microcirculatory changes than lactate, which is a lagging indicator. ANDROMEDA-SHOCK-2 provides definitive RCT support for CRT as a valid resuscitation endpoint, now incorporated into SSC 2026 guidelines. Critically, the CRT group used less fluid and started vasopressors earlier — two features consistent with harm-reduction in septic shock resuscitation. CRT is particularly valuable when Type B lactic acidosis is suspected (salbutamol, metformin, liver failure, haematological malignancy) where elevated lactate does not reflect hypoperfusion.

Tell your department: In every resus bay septic shock assessment: press the sternum (or knee or finger pad) firmly for 5 seconds. Release. Measure refill time. Normal ≤3 seconds = CRT normal. Incorporate CRT into every reassessment cycle alongside lactate and MAP. Do not let an elevated lactate drive more fluids if CRT and clinical signs are improving.

Critical appraisal: The composite primary endpoint incorporates multiple organ support components — this can be sensitive to how components are weighted and defined. 28-day mortality being identical between groups is reassuring (CRT approach is not harmful) but means the benefit is in organ support burden, not survival. The 9-country design improves generalisability. This trial directly supports SSC 2026 guidelines: use CRT alongside lactate, not instead of it.

Long E, Selman C, Borland ML et al; PREDICT network. Arch Dis Child. Published online 22 May 2026. PMID: 42173666

Paediatric IV Bolus Fluids and Mortality — Large Cohort Challenges Current Practice

CHANGE THIS MONTH COHORT STUDY PAEDS FRCEM

• OR 20.5 MORTALITY: BOLUS >55 VS <15 ML/KG
• Observational UNADJUSTED ORS CONFOUNDING RISK
• AUS/NZ NOT UK DATA INDIRECT EVIDENCE
• n=5,352 11 EDS 2021–2023

Design: Prospective observational multicentre cohort study. 11 EDs, Australia and New Zealand. 5,352 children aged 0–<18 years, community-acquired sepsis, hospitalised through ED. 2021–2023.

Key result: Bolus >55ml/kg vs <15ml/kg: unadjusted OR 20.5 for in-hospital mortality (95%CI 8.0–52.5, p<0.001). Maintenance fluids were NOT associated with mortality — the association was specific to bolus volumes. Overall in-hospital mortality was 1.1% (58/5,352). Median age 2.6 years. 5.5% met Phoenix sepsis criteria.

Safety alert: This directly follows Issue 17's paediatric septic shock fluids RCT (NEJM). Two independent studies now show that higher bolus fluid volumes are associated with worse outcomes in children with sepsis. Give 10–20ml/kg boluses, reassess clinically after EACH, and stop if signs of fluid overload develop. Do NOT reflexively complete 30ml/kg. SSC Children 2026 recommends up to 40–60ml/kg total only in settings with ICU/ventilation backup.

Critical appraisal: Observational study with unadjusted ORs. The extremely high OR for mortality in the high-bolus group almost certainly reflects severity confounding — sicker children receive more fluid because they are sicker. This is not an RCT and cannot prove causation. However, the paediatric septic shock RCT from Issue 17 (NEJM, 47 EDs) provides RCT-level support for a conservative fluid approach. A consistent signal from two independent studies using very different designs is meaningful and should inform cautious practice.

Action in practice: Reassess after EVERY bolus in paediatric sepsis. Use clinical signs (CRT, HR, BP, mental status) rather than a target volume to guide further boluses. Stop immediately if hepatomegaly, basal crackles, or worsening oxygen requirement develop — these are signs of fluid overload. If clinical signs are deteriorating despite 20ml/kg, start vasopressor (noradrenaline or dopamine) rather than giving more fluid.

Jeffers K, Keim SM, Long B, Gottlieb M, Adhikari SR. J Emerg Med. 2026. PMID: 42176469

Ocular POCUS for Retinal Detachment — High Performance but Beware Non-Vitreoretinal Pathology

INFORMING PRACTICE DIAGNOSTIC ACCURACY FRCEM

Design: Diagnostic accuracy study of EP-performed ocular POCUS vs ophthalmological examination as reference standard.

*Includes retinal vascular disease, CRAO, ischaemic optic neuropathy. Sn 13.3% means POCUS MISSES 87% of these diagnoses.

Overall agreement with ophthalmology: κ=0.48 (moderate). 91.5% were referred to ophthalmology regardless of POCUS result.

Bayesian post-test probabilities for retinal detachment:

Safety alert: A negative ocular POCUS does NOT rule out retinal vascular disease, CRAO, or ischaemic optic neuropathy. Sensitivity for these diagnoses is only 13.3%. Any patient with sudden painless visual loss and risk factors for vascular disease (hypertension, atrial fibrillation, diabetes, hyperlipidaemia) must still be referred urgently to ophthalmology regardless of POCUS findings.

Why it matters: Use POCUS to rule IN retinal detachment (LR+ 15.1 is a strong rule-in test). A positive POCUS in a 30% pre-test probability patient takes post-test probability to 87% — enough to act on urgently. However, the test's weakness is in non-vitreoretinal pathology. A negative POCUS in the context of acute visual loss cannot be used to reassure. This is a fundamental diagnostic limitation that must be communicated to trainees using POCUS in eye complaints.

Cashin AG, Chou R, Weimer MB, McAuley JH. JAMA. Published online 15 June 2026. doi:10.1001/jama.2026.9631

Low Back Pain: A Narrative Review (JAMA 2026) — 90% Nonspecific, Imaging NOT Indicated

INFORMING PRACTICE

NARRATIVE REVIEW

FRCEM

Design: Narrative review + guideline synthesis. 108 studies: 50 meta-analyses, 18 RCTs, 15 SRs, 8 international guidelines including NICE NG59.

Red flags requiring immediate imaging:

• Saddle anaesthesia / perianal numbness + urinary retention or incontinence = emergency MRI for cauda equina
• Progressive motor weakness in lower limbs
• Fever + IVDU background (vertebral osteomyelitis)
• History of malignancy + new back pain (metastatic disease)
• Significant trauma (fracture)

UK context: RCEM estimates 15,860 excess deaths per year linked to ED waits. ED efficiency partly depends on reducing unnecessary imaging and inappropriate opioid prescribing. LBP without red flags: take a clinical history, reassure, prescribe NSAIDs, advise staying active, discharge with safety-netting for cauda equina symptoms. No XR, no CT, no MRI from the ED. Audit action: Check your department's uncomplicated LBP imaging rate and cross-reference with NICE NG59.

Critical appraisal: Narrative review rather than a systematic review, so it is subject to selection bias in which studies are emphasised. However, all conclusions align with NICE NG59 and multiple international guidelines. The recommendation against opioids first-line is well-supported by evidence from multiple RCTs and guidelines. The 90% nonspecific figure is a well-established epidemiological finding. This review is best used as a teaching reference and for audit purposes rather than practice-changing on its own.

SECTION 2 — GUIDELINES & UK UPDATES

UKHSA Red Heat-Health Alert. Issued 22 June 2026. Active as of 25 June 2026. ukhsa-dashboard.data.gov.uk

UKHSA RED HEAT-HEALTH ALERT — 6 English Regions — Active Now

CHANGE TONIGHT

Current status (25 June 2026): Red Heat-Health Alert active in 6 English regions — South East, South West, East of England, London, East Midlands, West Midlands. Amber Alert in remaining regions.

Heat stroke = resuscitation emergency: Core temperature ≥40°C + CNS dysfunction (confusion, seizure, coma). COOL IMMEDIATELY — ice packs to neck, axillae, and groin. Target core temp ≤39°C BEFORE investigations. Do not let the workup delay cooling by even one minute.

Drug toxicity screen — mandatory in all elderly and exertional heat presentations:

• Lithium: Volume depletion from sweating → reduced renal clearance → toxicity. Check level in all patients on lithium.
• Digoxin: Hypokalaemia (from sweating, diuretics) sensitises to digoxin toxicity. Check level + K+.
• Diuretic-induced electrolyte disturbances: Check UE in ALL heat-related presentations.
• AKI: Common and underrecognised. Suspend NSAIDs, ACEi, ARBs in all heat-affected at-risk patients.

Tell your team tonight: Heat stroke management order: (1) recognise, (2) cool immediately to <39°C with ice packs, (3) then investigate. Check lithium/digoxin levels and UE in every elderly or exertional heat presentation. Stop nephrotoxics.

UKHSA Measles Update. 25 June 2026. England.

UKHSA MEASLES UPDATE — 801 Cases, 2 Child Deaths, WHO Elimination Status Lost

CHANGE TONIGHT

Epidemiology (as of 22 June 2026): 801 confirmed cases in England — 84% of all 2025 case volume already exceeded. 2 child deaths in 2026, the first two in a single calendar year since 2018. England has formally lost WHO measles elimination status. A national 2026/27 MMR catch-up campaign targeting unvaccinated children has been launched.

Emergency department action from TONIGHT: Airborne precautions from triage for any child with fever + coryza + cough (do not wait for rash). Place in a negative pressure room if available. Measles is a NOTIFIABLE DISEASE — notify UKHSA within 24 hours of a confirmed or suspected case. A single confirmed case requires a public health response.

Clinical features to recognise:

• Prodrome: High fever, coryza, cough, conjunctivitis (the "3 Cs")
• Koplik's spots: Bluish-white spots on buccal mucosa — present 1–2 days BEFORE the rash appears. Pathognomonic.
• Rash: Maculopapular, begins at hairline and spreads downward. Appears day 3–5 of illness.
• Complications: Pneumonia (commonest cause of death), encephalitis (1/1,000 cases), SSPE (subacute sclerosing panencephalitis — late complication 5–10 years post-infection)

Ask and document MMR vaccination status for every febrile child. Two doses of MMR are needed for full protection. Document status and alert health visitor/GP if incomplete.

NHS England. A&E Attendances and Emergency Admissions — May 2026. Published 11 June 2026.

NHS England May 2026 A&E Statistics — Record Attendances, Corridor Care Quantified

INFORMING PRACTICE

RCEM comment: "This data must drive structural action, not just corridor management protocols." The first official quantification of corridor care (2,241 patients/day in EDs) finally puts a number to what every UK emergency clinician sees daily. The 121-fold increase in 12-hour waits since 2019 represents the defining quality and safety crisis of this generation of NHS emergency medicine.

Intensive Care Society State of the Art Conference 2026 (ICS SOA26). ICC Birmingham. 30 June – 2 July 2026.

ICS SOA26 Next Week — BICARICU-2, ANDROMEDA-SHOCK-2, MARCH Deep-Dives

GUIDELINE WATCH

The ICS State of the Art Conference (30 June – 2 July, ICC Birmingham) is expected to present:

• BICARICU-2 full results — first large definitive RCT of bicarbonate in severe metabolic acidosis + AKI (n=640). If positive for RRT reduction, this will become the definitive evidence informing the SSC conditional recommendation.
• ANDROMEDA-SHOCK-2 deep-dive session — full secondary analysis and subgroup data.
• MARCH and BIHCA poster discussions — UK-specific implementation analysis.
• iRehab ICU rehabilitation trial — early mobilisation data.

Issue 19 (2 July 2026) will provide full coverage of all ICS SOA26 outputs. If you attend, note the BICARICU-2 results carefully — these will determine whether the SSC 2026 conditional bicarb recommendation strengthens or weakens. If BICARICU-2 confirms RRT reduction, the recommendation becomes more actionable for the specific pH ≤7.2 + AKI Stage 2-3 indication.

JCVI-approved MenB vaccination programme announcement. NHS England. June 2026.

Meningococcal B University Programme Opens 20 July 2026 — Maintain Low LP Threshold Now

CHANGE TONIGHT GUIDELINE WATCH

The JCVI-approved MenB vaccination programme for university freshers opens nationally on 20 July 2026. The announcement was preceded by the largest-ever MenB outbreak in Kent (early 2026).

Until herd immunity builds: Maintain a low threshold for lumbar puncture in ALL young adults presenting with any meningism (neck stiffness, photophobia, phonophobia, non-blanching rash). MenB is not covered by MenACWY (which has been offered to freshers since 2015). A vaccinated student can still develop MenB. Do not be falsely reassured by MenACWY vaccination history.

Clinical reminder: Meningococcal septicaemia can present without meningism in up to 20% of cases. A non-blanching rash in a febrile young adult is a meningococcal emergency until proven otherwise. Give IV benzylpenicillin immediately (or ceftriaxone if penicillin allergy) and transfer to hospital. Do not wait for investigations.

SECTION 3 — PAEDIATRIC EMERGENCY MEDICINE

Long E et al. Arch Dis Child. 2026. PMID: 42173666 — Lead paediatric item covered in full in Section 1 (Item 5).

PEM Lead: Paediatric IV Bolus Fluids and Mortality — See Section 1 for Full Detail

CHANGE THIS MONTH PAEDS

Summary: n=5,352 children. Bolus >55ml/kg: OR 20.5 for mortality (95%CI 8.0–52.5). Two independent studies (this cohort + Issue 17 NEJM RCT) now consistently show large fluid boluses are associated with harm in paediatric sepsis. Give 10–20ml/kg boluses, reassess after each, stop if overload signs. Full analysis in Section 1 ↑

PREDICT Network authors. Eur J Pediatr. 2026. PMID: 42176112

Paediatric Trauma Score + Lactate Combined for Triage — AUC 0.936 vs 0.812

INFORMING PRACTICE PAEDS

Combined paediatric trauma score + point-of-care lactate achieved AUC 0.936 for predicting mortality in paediatric compound trauma, vs AUC 0.812 for clinical score alone. Adding a simple lactate measurement to standard paediatric trauma scoring significantly improves triage accuracy for the highest-risk children.

Why it matters: In any paediatric trauma activation in a UK ED, obtain a POC lactate alongside your clinical trauma score assessment. A lactate ≥4 mmol/L in a paediatric trauma patient should prompt immediate escalation regardless of clinical score. This is a simple, low-cost addition to existing triage workflows.

Arch Dis Child. 2026. PMID: 42173667

Risk Mitigation for Paediatric Mental Health Crisis in Acute Paediatric Care — 16 Consensus Strategies

INFORMING PRACTICE PAEDS

Consensus-based paper providing 16 risk mitigation strategies for children and young people (CYP) in mental health crisis admitted to paediatric wards and EDs. Covers structured risk checks (regular safety assessment, clear escalation pathways), therapeutic engagement (designated key worker, therapeutic holding as last resort), and environmental controls (ligature risk assessment, securing harmful items).

UK relevance: Directly applicable to UK paediatric EDs holding CYP in mental health crisis overnight due to CAMHS capacity gaps. Review your department's practice against these 16 strategies. HSSIB final MH in EDs report (Report 2 of 2) expected summer 2026 — watch for structural recommendations on HBPoS alternatives.

J Trauma Acute Care Surg. 2026. PMID: 42173520

Initial Identification and Management of Severely Injured Paediatric Trauma in Non-Paediatric EDs

INFORMING PRACTICE PAEDS

Framework paper for trauma activation criteria, early recognition of deterioration, and coordinated MDT care for severely injured children presenting to EDs without paediatric trauma designation. Key components: paediatric-specific activation thresholds (adjusted vital sign parameters by age), early senior involvement, HEMS/PICU liaison, and clear transfer criteria.

UK relevance: The majority of UK EDs are not paediatric trauma centres. Every district general hospital ED team needs a clear protocol for paediatric major trauma activation, initial management, and regional PICU/paediatric surgical centre transfer. Review your local paediatric major trauma pathway and ensure senior review criteria are explicit. Know your nearest paediatric trauma/PICU centre and the HEMS activation number.

SECTION 4 — FOAMED & CRITICAL APPRAISAL

Critical Care Reviews Meeting 2026 (CCR26). Belfast, 11 June 2026. criticalcarereviews.com

CCR26 Belfast — BIHCA, MARCH, ANDROMEDA-SHOCK-2: The Week the Bicarb Reflex Was Dismantled

INFORMING PRACTICE

CCR26 hosted simultaneous presentations of BIHCA and MARCH alongside a detailed ANDROMEDA-SHOCK-2 discussion on 11 June 2026. CCR26 is one of the highest-quality critical care evidence synthesis meetings internationally. The CCR website (criticalcarereviews.com) has detailed trial summaries for all three trials — strongly recommended as a reference for this week's clinical conversations.

Editorial note: The simultaneous publication and presentation of BIHCA, MARCH, and SODa-BIC in the same week of June 2026 represents a coordinated re-evaluation of reflexive bicarbonate and mucoactive agent use in critical illness. This is not coincidence — CCR26 programme organisers specifically curated this evidence cluster. The clinical bottom line from CCR26: stop using bicarbonate as a routine drug in shock or cardiac arrest; reserve it for mechanistic indications (hyperkalaemia, sodium-channel toxicity, severe AKI + pH ≤7.2). Stop mucoactive agents routinely in ventilated patients. These messages will likely reach RCUK, FICM, and ICS guidelines within 12 months.

SECTION 5 — QUICK HITS

Quick Hit 1: Serratus Anterior Plane Block for Rib Fractures in the ED

INFORMING PRACTICE

Acad Emerg Med. PMID: 42159402. n=38. EP-performed serratus anterior plane block (SAPB).

EP-performed SAPB significantly improved pain scores, inspiratory capacity, and cough effort vs usual care in ED patients with rib fractures. Very small trial (n=38) but ED-specific and building on the SABRE RCT (referenced in Issues 5/7). The evidence base for EP-performed truncal blocks for rib fractures is accumulating.

Action: If you have not yet learned SAPB or erector spinae plane block (ESPB) for rib fractures, this is worth prioritising on your next POCUS/regional anaesthesia training day. These blocks are within the competence of emergency physicians and have meaningful analgesic impact for a painful and common presentation.

Quick Hit 2: Helicopter ECPR — FLIGHT-to-ECPR (Resuscitation 2026)

INFORMING PRACTICE

FLIGHT-to-ECPR Study. Resuscitation. 2026.

Helicopter-facilitated ECPR expands rural and regional access to extracorporeal cardiopulmonary resuscitation for refractory out-of-hospital cardiac arrest without compromising neurological outcomes compared to ground-based ECPR at urban centres.

UK context: If your centre has ECPR capability (typically tertiary centres with cardiac surgery/cath lab), ensure you have clear activation criteria, team roles, and response times established. For non-ECPR centres, know your regional ECPR centre and HEMS activation pathway. Helicopter-facilitated retrieval for refractory OHCA with witnessed arrest, short downtime, and shockable rhythm is the emerging standard.

SECTION 6 — CORE REVISION: LACTATE — BEYOND THE NUMBER

CORE REVISION — LACTATE: BEYOND THE NUMBER

Why this week: Three trials in Issue 18 directly touch lactate — SODa-BIC (treating acidosis from elevated lactate), ANDROMEDA-SHOCK-2 (CRT superior to lactate-alone endpoint), and paediatric bolus data (lactate in PTS scoring). This is the ideal week for the lactate revision pearl.

1. What lactate actually measures

Lactate is produced when pyruvate cannot enter the TCA cycle — due to inadequate oxygen delivery, mitochondrial dysfunction, or metabolic override. In normal aerobic metabolism, pyruvate is converted to acetyl-CoA by pyruvate dehydrogenase (PDH). When oxygen delivery falls or PDH is inhibited, pyruvate accumulates and is converted to lactate by lactate dehydrogenase (LDH).

• Normal: ≤2.0 mmol/L
• Hyperlactataemia: ≥2 mmol/L
• Lactic acidosis: ≥5 mmol/L (+ metabolic acidosis)

2. Type A vs Type B Lactic Acidosis

Type B causes — the "pitfalls" (FRCEM exam favourite):

• Metformin: Mitochondrial complex I inhibition. Especially in AKI, contrast administration, dehydration.
• Thiamine deficiency/Wernicke's: Blocks pyruvate dehydrogenase (PDH) → pyruvate cannot enter TCA cycle.
• Linezolid: Mitochondrial toxicity with prolonged use.
• Nucleoside analogue antivirals (e.g. stavudine, didanosine): Mitochondrial DNA inhibition.
• Salbutamol/adrenaline: Beta-2 receptor stimulation → hepatic and skeletal muscle lactate production (not hypoperfusion).
• Severe liver failure: Cannot metabolise lactate efficiently. Elevated lactate in decompensated cirrhosis may not reflect tissue hypoxia.
• Haematological malignancy (Warburg effect): Tumour cells preferentially produce lactate even in aerobic conditions.
• Carbon monoxide poisoning: Blocks cytochrome c oxidase → functional tissue hypoxia despite normal SpO2 and PaO2.
• Seizures: Vigorous muscle contraction → transient lactate rise. Resolves within 60 minutes. Not a shock marker.
• D-lactate: Short bowel syndrome, bacterial overgrowth. Standard assays measure L-lactate only — D-lactate requires specific assay.

3. Lactate as a Resuscitation Endpoint — Limitations

• Lactate clearance ≥10% per 2h is a reasonable resuscitation goal but is a lagging indicator — it reflects history, not current perfusion state.
• CRT responds faster to changes in perfusion pressure and microcirculation — more real-time, no laboratory required.
• ANDROMEDA-SHOCK-2: CRT-guided groups did not worsen lactate clearance; CRT + lactate together outperforms lactate alone.
• Serial trend matters more than absolute value. A lactate rising from 2.0 to 3.0 mmol/L despite treatment is more concerning than a static 3.0 mmol/L in a patient who is clinically improving and has a clear Type B cause.

4. Common Pitfalls in Lactate Interpretation

5. Key Exam Point (FRCEM)

Septic shock definition (Sepsis-3): Requires BOTH vasopressor need AND lactate >2 mmol/L DESPITE adequate fluid resuscitation. The lactate threshold is part of the diagnostic criteria, not just a monitoring tool. Patients meeting clinical criteria for shock but with lactate ≤2 mmol/L post-resuscitation do NOT meet the Sepsis-3 definition of septic shock — this affects prognostication and trial enrolment criteria. SSC 2026 now incorporates CRT as a parallel resuscitation endpoint alongside lactate.

6. SALT Mnemonic for Resuscitation Endpoints

SALT — RESUSCITATION ENDPOINTS

S Sats — SpO2 94–98% A Arterial pressure — MAP ≥65 mmHg L Lactate trend — clearance ≥10% per 2h + CRT ≤3s T Temperature — correction (>36°C in septic shock; <38°C for fever)

SECTION 7 — ACTION POINTS

8 ACTIONS FROM ISSUE 18

SECTION 8 — TRIALS TO WATCH

Imminent (Q2–Q3 2026)

• ICS SOA26 (30 June – 2 July, ICC Birmingham): BICARICU-2 full data (bicarb in severe metabolic acidosis + AKI, n=640 — first large definitive RCT for this specific indication), ANDROMEDA-SHOCK-2 deep-dive, MARCH and BIHCA poster discussions. Full coverage in Issue 19 (2 July 2026).
• EVIS UK Trial (NCT05179499): Early peripheral vasopressors in UK septic shock (n=3,286). Direct UK equivalent of ARISE FLUIDS. Expected 2026–2027. Will determine UK guideline on vasopressor timing in septic shock.
• BACHb Trial: HFNC vs standard O2 vs CPAP in bronchiolitis (UK, 50+ sites). Expected 2026. Will directly inform one of the most common paediatric winter presentation protocols.

2026–2027

• BEST-DKA Phase 3: Balanced electrolyte solution vs normal saline in DKA. Could change one of the most common ED critical illness protocols. Phase 2 favoured balanced solution.
• HSSIB Mental Health Crisis in EDs — Final Report 2 of 2: Expected summer 2026. Will include recommendations on HBPoS alternatives, psychiatric liaison models, and structural solutions for MH crisis in EDs.

Longer Horizon

• CoMiTED: Conservative vs immediate chest drain management in traumatic pneumothorax. Awaited.
• CABARET: Head-up CPR bundle feasibility trial. Will inform any future role for head-up positioning during cardiac arrest.

Jake Turner

Curated with the assistance of AI (Perplexity). All content editorially reviewed.

emevidence.org | Submit feedback | Issue 18, 25 June 2026

EM Evidence Rundown is produced weekly for UK emergency medicine clinicians. Content is editorially reviewed but does not constitute individual clinical advice. Always apply evidence in the context of local guidelines and individual patient circumstances. Sources: JAMA (doi:10.1001/jama.2026.10628), NEJM (PMID: 42267821), JAMA (PMID: 42283370 / 42171427), JAMA (ANDROMEDA-SHOCK-2), Arch Dis Child (PMID: 42173666), J Emerg Med (PMID: 42176469), JAMA (doi:10.1001/jama.2026.9631), UKHSA, NHS England, Eur J Pediatr (PMID: 42176112), Arch Dis Child (PMID: 42173667), J Trauma Acute Care Surg (PMID: 42173520), Acad Emerg Med (PMID: 42159402), Resuscitation 2026 (FLIGHT-to-ECPR), criticalcarereviews.com.