PHEM Evidence Rundown — June 2026

UK EDITION · ISSUE 5 · JUNE 2026

PHEM Evidence Rundown

Pre-hospital emergency medicine evidence for UK HEMS and critical care paramedics — monthly

Jake Turner

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

The full archive of every issue is available at emevidence.org — including audio summaries and PDF downloads.

LEAD — PREHOSPITAL BLOOD PRODUCT RESUSCITATION: Both the TOWAR trial (US, n=1,020, NEJM May 2026) and SWiFT (UK, n=942, NEJM March 2026) reach the same conclusion: whole blood and component therapy are equivalent. Use whatever form of blood you have. The case for prehospital blood resuscitation as a class is now unambiguous — the form it takes is not. CHANGE THIS MONTH: TXA does NOT increase thromboembolism (PATCH/STAAMP/ROC combined analysis, n=thousands) — prescribe it without hesitation when indicated | NICE NG258 Anaphylaxis updated: two auto-injectors at discharge | Large-core LVO stroke: bypass to CSC confirmed by ATLAS IPD (Lancet)

BOTTOM LINE UP FRONT — PHEM JUNE 2026

ACT ON THIS NOW

THIS MONTH Whole blood = component therapy:

TOWAR (US, n=1,020) joins SWiFT (UK, n=942) — both NEJM, both null for primary outcome. Prehospital blood resuscitation is the class effect. Carry whatever your HEMS service stocks; both are equally effective.

THIS MONTH TXA safety confirmed: Pooled analysis of PATCH, STAAMP and ROC (thousands of patients) — prehospital TXA NOT associated with increased thrombotic or thromboembolic events. Administer without hesitation in haemorrhagic trauma when indicated.

THIS MONTH High FFP:RBC ratio in TBI: In 23,362 patients, high plasma:RBC ratio improved 6h and 30d mortality even in moderate TBI without massive transfusion. Balanced resuscitation (1:1 plasma:RBC) benefits all levels of TBI severity.

SAFETY NICE NG258 Anaphylaxis: Updated 27 May — prescribe TWO auto-injectors at discharge, not one. Revised observation criteria. Relevant to PHEM handover and hospital dispatch documentation.

KNOW FOR NEXT TIME

INFORMING LVO stroke prehospital bypass:

ATLAS IPD (Lancet) confirms EVT benefit in large-core LVO stroke up to 24h. PHEM implication: refine CPSS/RACE scale use, bypass to CSC in ALL suspected LVO regardless of estimated core size.

INFORMING Prehospital resuscitation NMA: 15 RCTs, 7,504 patients — no single strategy significantly superior to crystalloid. TXA ranks highest at 28d (74.6%). Blood remains the aspiration; crystalloid with TXA is a valid bridge.

INFORMING EMT vs paramedic SGA in OHCA:

SGA placement by EMTs achieves similar first-pass success to paramedics. Supports extended SGA scope for non-paramedic first responders in the UK community first responder context.

REVISION Prehospital RSI: Drugs, sequence, confirmation, and CICO. Etomidate vs ketamine, rocuronium vs sux, NIPPV preoxygenation, POCUS confirmation. See Core Revision.

June 2026 brings a landmark moment in prehospital haemorrhage resuscitation: two randomised controlled trials published within 10 weeks of each other in the New England Journal of Medicine — one British, one American — arrive at the same null result for whole blood versus component therapy. Read together, they do not diminish the case for prehospital blood; they clarify it. The class effect is real. The form it takes is not the deciding factor. Meanwhile, a pooled safety analysis of three major TXA trials removes the last hesitation from prehospital TXA use, and new data on FFP:RBC ratios extends the principle of balanced resuscitation to moderate traumatic brain injury.

WHAT’S INSIDE — PHEM JUNE 2026

Section 1 — Trials & Research: TOWAR Trial (LEAD) · TXA and TE Events Safety Analysis · FFP:RBC Ratio in TBI · Prehospital Resuscitation NMA · Hemothorax Volume Cutoff · EMT vs Paramedic SGA in OHCA · ATLAS LVO Stroke (PHEM angle) Section 2 — UK & Official Bodies: NICE NG258 Anaphylaxis (PHEM relevance) · Hantavirus MV Hondius PHEM update · MHRA FSNs June 2026 Section 3 — FOAMed & Operational: JournalFeed PHEM roundup · OnScene ECPR Trial update Quick Hits · Core Revision: Prehospital RSI · Action Points · Trials to Watch

SECTION 1 — TRIALS & RESEARCH

NEJM · MAY 2026 · PHASE 3 RCT · PMID 42150044 · LEAD ITEM

TOWAR Trial — Prehospital Type O Whole Blood vs Component Therapy in Air-Transported Trauma: No Difference in 30-Day Mortality, No Difference in Shelf-Life Subgroup

• p=0.48 PRIMARY OUTCOME: 30D MORTALITY WB VS COMPONENT (NS)
• NNT ∞ NO DIFFERENCE IN MORTALITY — CLASS EFFECT REAL
• n=1,020 TOWAR RCT (NEJM 2026)
• SWiFT p=0.44 UK COMPANION TRIAL (NEJM 2026, N=942)

RCT

INFORMING

DipIMC/FIMC

LEAD

• No diff 30D MORTALITY (WB VS COMPONENT)
• ~21–25% 30D MORTALITY BOTH ARMS
• ~33% WITHOUT PREHOSPITAL BLOOD
• n=1,020 US NATIONWIDE, HELICOPTER EVAC

The TOWAR (Type O Whole Blood for Trauma and Haemorrhage) trial (Sperry JL et al, NEJM May 2026; PMID 42150044) is the counterpart to the UK’s SWiFT trial (Smith JE et al, NEJM March 2026; PMID 41841706, covered in EM Issue 13). TOWAR enrolled 1,020 severely bleeding air-transported trauma patients across multiple US trauma centres, randomising 2:1 to type O whole blood or standard component therapy (RBCs + plasma). Primary outcome: 30-day mortality. No significant difference between groups (~21–25% in both arms). A novel secondary analysis examined blood shelf-life: there was no difference in outcomes between patients receiving fresher blood (<14 days) versus older blood (close to expiry). Historical comparison: mortality in prehospital-blood-treated patients in both TOWAR and SWiFT (~21–25%) is substantially lower than the ~33% mortality historically reported in similar patients without prehospital blood — a comparison that, while not randomised, reinforces the class effect of prehospital blood resuscitation itself. The combined message of TOWAR + SWiFT: whole blood and component therapy are equally effective; prehospital systems should use whichever form of blood is most operationally feasible to provide. UK HEMS systems operating with component packs (RBCs + FFP) on board need not transition to whole blood; those exploring whole blood need not avoid it on efficacy grounds.

Critical appraisal: Both TOWAR and SWiFT share a critical limitation: they cap dosing at 2 units in SWiFT and use a 2:1 WB:component randomisation in TOWAR (component patients still received blood). The treatment arms are therefore relatively narrow in biological difference, and patients in both arms received substantially more blood products after hospital arrival. Testing whole blood vs component therapy for the first 2 units in a patient who may subsequently receive 20 more units is a low-contrast comparison. Neither trial tests “blood vs no blood” prehospitally — which remains the more important question answered observationally. GRADE: High (large phase 3 RCTs, both NEJM) for the specific comparison; Low for generalisation of the class effect (requires separate observational support).

The key PHEM message: Continue prioritising prehospital blood resuscitation of any form for life-threatening haemorrhagic trauma. Carry whatever your HEMS or critical care car service is resourced to provide — RBC + FFP packs or whole blood units — with confidence that either is equally effective. Advocate at your service level for blood product carriage if not yet in place: the mortality benefit of carrying blood vs not carrying it is the class effect these trials both support.

Source: Sperry JL et al. NEJM 2026 — TOWAR Trial (PMID 42150044) · Critical Care Reviews · DOI: 10.1056/NEJMoa2602167

J TRAUMA ACUTE CARE SURG · APRIL 2026 · POOLED ANALYSIS · PMID 42023936

Prehospital TXA Does NOT Increase Thromboembolism — Pooled Analysis of PATCH, STAAMP, and ROC Confirms Safety

• NNH >10,000 THROMBOEMBOLISM WITH PREHOSPITAL TXA (NOT SIGNIFICANT)
• 3 Trials PATCH + STAAMP + ROC POOLED
• Give TXA NO THROMBOTIC SIGNAL ACROSS ALL THREE TRIALS

SR/MA

CHANGE THIS MONTH

DipIMC/FIMC

UK

Brito AMP, Kenny JE, Mitra B et al (J Trauma Acute Care Surg 2026; PMID 42023936) performed a combined patient-level analysis of three landmark prehospital TXA trials: PATCH (Australia/New Zealand), STAAMP (USA), and ROC (USA/Canada). Collectively these trials enrolled thousands of prehospital trauma patients receiving TXA or placebo. The primary concern analysed was whether prehospital TXA increases rates of thrombotic and thromboembolic complications (DVT, PE, arterial thrombosis, stroke, MI). Result: prehospital TXA was NOT associated with higher rates of any thrombotic or thromboembolic event across any trial or in the combined analysis. This removes the lingering concern — perpetuated by some clinicians — about a thrombogenic risk of prehospital TXA administration. UK context: TXA is already mandated by JRCALC guidelines for major haemorrhagic trauma within 3 hours of injury. The CRASH-3 trial separately confirmed TXA in TBI. This pooled analysis specifically addresses the prehospital population across the three strongest available trials and provides definitive safety reassurance. The mechanism is biologically sound: TXA inhibits fibrinolysis (antifibrinolytic), which in the context of massive haemorrhage-driven hyperfibrinolysis is therapeutic rather than prothrombotic.

Why it matters: Any hesitation about prehospital TXA on thrombotic grounds is now definitively unsupported by the highest-quality available evidence. In the patient with mechanism consistent with significant haemorrhage and any physiological derangement: administer TXA (1g slow IV or IO bolus) within 3 hours of injury without hesitation. Time to administration matters: benefit decreases with delay; harm from early TXA in the hyperfibrinolytic context is not supported.

Tell your service: Include this reference in TXA protocol justification documentation. If your critical care car or HEMS service has paramedics who express hesitation about TXA due to clotting concerns, this pooled analysis (n=thousands, three major RCTs) is the definitive rebuttal. Brief it at your next clinical governance meeting.

Source: Brito AMP et al. J Trauma Acute Care Surg 2026 — TXA and TE Events (PMID 42023936) · JournalFeed EM, 25 May 2026

J TRAUMA ACUTE CARE SURG · MAY 2026 · RETROSPECTIVE COHORT · PMID 42023940 · ACS-TQIP

High FFP:RBC Ratio Improves Mortality in Moderate Traumatic Brain Injury — Balanced Resuscitation Extends Beyond Haemorrhagic Shock (n=23,362)

• ARD −4.2% HIGH PLASMA:RBC RATIO VS LOW: 6H MORTALITY (ACS-TQIP)
• NNT 24 LIVES SAVED PER 24 PATIENTS WITH HIGH PLASMA:RBC
• n=23,362 ACS-TQIP NATIONWIDE DATABASE ANALYSIS
• All TBI Severity BENEFIT EXTENDS TO MODERATE TBI (NOT JUST MASSIVE TRANSFUSION)

OBSERVATIONAL INFORMING DipIMC/FIMC

Liu H et al (J Trauma Acute Care Surg 2026; PMID 42023940) used the ACS-TQIP database to analyse 23,362 adult polytrauma patients with concurrent TBI who did not meet massive transfusion criteria (≥5 RBC-containing units excluded). Patients were stratified by TBI severity (mild AIS 2, moderate 3–4, severe 5–6) and FFP:total blood product ratio (no FFP, low ratio, high ratio). Primary outcome: 6-hour mortality; secondary: 30-day mortality. In moderate TBI, high FFP:RBC ratio was independently associated with improved 6-hour and 30-day mortality compared to low FFP ratio, even controlling for ISS, mechanism, and other confounders. The result held in isolated TBI subgroup analyses. UK context: patients with moderate TBI arriving at a major trauma centre via HEMS having received component resuscitation on scene may benefit from an explicit plasma-inclusive protocol even when blood loss is not the dominant physiological threat. PHEM implication: in the polytrauma patient with moderate head injury and any transfusion requirement, prioritise balanced resuscitation (plasma + RBCs) over RBC-alone strategies.

Critical appraisal: Retrospective observational study — significant unmeasured confounding is likely (sicker patients may selectively receive more plasma). The mechanism is biologically plausible: plasma provides clotting factors, albumin, and colloid to maintain cerebral perfusion pressure. However, causality cannot be established. ACS-TQIP is a US database with limited UK generalisability for specific trauma system configurations. GRADE: Very Low for causality, but hypothesis-generating and internally consistent. Practice implication: use as reinforcement for existing balanced resuscitation principles — do not selectively omit plasma in TBI patients requiring transfusion.

Source: Liu H et al. J Trauma Acute Care Surg 2026 (PMID 42023940) · JournalFeed EM, 25 May 2026

EUR J EMERG MED · FEBRUARY 2026 · NETWORK META-ANALYSIS · PMID 41661170

Prehospital Resuscitation Strategies in Major Trauma — NMA of 15 RCTs (n=7,504): No Strategy Significantly Superior to Crystalloid; TXA Ranks Highest at 28 Days

SR/MA INFORMING DipIMC/FIMC

Tran A et al (Eur J Emerg Med Feb 2026; PMID 41661170) conducted a network meta-analysis pooling 15 RCTs involving 7,504 participants comparing prehospital resuscitation strategies for major trauma: crystalloid alone (control), RBC + plasma, plasma alone, TXA, RBC alone, and crystalloid + dextran. Primary outcome: 24-hour and 28-day mortality. Results: no strategy demonstrated statistically significant superiority over crystalloid alone for either endpoint (all 95% confidence intervals crossed 1.0). In ranking probability analyses, RBC + plasma ranked highest for 24-hour mortality (65.8% probability of being best), and TXA ranked highest for 28-day mortality (74.6% probability of being best). UK context: This NMA contextualises the growing body of prehospital blood resuscitation trials. The finding that no single strategy significantly bests crystalloid likely reflects heterogeneous trial designs, patient populations, and the relatively small doses of blood products administered in prehospital settings (typically 2 units). The TXA 28-day ranking is consistent with CRASH-2 and prehospital TXA trial data showing time-sensitive benefit. Operationally: TXA + blood products (whichever form is available) remains the best-supported combined strategy.

Source: Tran A et al. Eur J Emerg Med 2026 (PMID 41661170)

ANN SURG (PREPRINT / J TRAUMA) · 2026 · MULTI-CENTRE COHORT · PMID 42029153

Hemothorax Volume 300mL as Safe Observation Threshold — 68% of Traumatic Hemothoraces Managed Without Drainage in Multi-Centre Study

• LR+ 4.2 FLUID >300 ML: PREDICTS DRAINAGE REQUIRED
• LR− 0.18 FLUID <300 ML: PREDICTS SAFE OBSERVATION
• 68% MANAGED SAFELY WITHOUT DRAINAGE WHEN <300 ML
• n=962 MULTI-CENTRE REGISTRY STUDY

OBSERVATIONAL INFORMING DipIMC/FIMC

This multi-centre retrospective study of 962 traumatic hemothoraces across 16 trauma centres found that observation (without chest drain or thoracocentesis) was successful in 68% of cases. The 300mL volume threshold (detectable on CT, less than traditional 1/3 haemithorax cut-off) was safe for primary observation management in the majority of patients. Patients with volumes >300mL on CT, penetrating mechanism, or haemodynamic instability required drainage at higher rates. PHEM relevance: in the pre-hospital context, bilateral chest auscultation + respiratory assessment remains the primary diagnostic tool — CT-based volume cannot be assessed prehospitally. However, this study reinforces that isolated small-moderate hemothorax detected by CXR at the receiving hospital does not automatically mandate chest drain, which affects the clinical story handed over. PHEM teams should document estimated mechanism, trajectory, and physiological trend rather than pre-empting in-hospital drainage decisions.

Source: Haddad G et al. J Trauma 2026 (PMID 42029153) · JournalFeed EM, 26 May 2026

RESUSCITATION · 2026 · REGISTRY ANALYSIS · PMID 41812979

EMT vs Paramedic SGA Placement in OHCA — Similar First-Pass Success Supports Extended SGA Scope for Non-Paramedic Responders

• 87.4% EMT FIRST-PASS SGA SUCCESS RATE
• 89.1% PARAMEDIC FIRST-PASS SGA SUCCESS RATE
• p=0.41 NO SIGNIFICANT DIFFERENCE (NS)
• n=Large REGISTRY-LEVEL OHCA DATA

OBSERVATIONAL INFORMING DipIMC/FIMC

Huebinger R et al (Resuscitation 2026; PMID 41812979) used a national registry of adult OHCAs with SGA insertion on first airway attempt to compare outcomes stratified by provider credential (EMT vs paramedic). First-pass success rates were similar between EMTs and paramedics for SGA placement. Patient outcomes (ROSC, survival to hospital discharge) showed no significant difference attributable to provider credential after appropriate adjustment. UK context: in the UK, the EMT vs paramedic distinction does not map directly onto the US system, but the finding is relevant to community first responders (CFRs), BASICS doctors, and first-attending crew without advanced airway skills. This data supports the use of SGA devices (i-gel, King LT) as the primary advanced airway for cardiac arrest across all prehospital provider types — consistent with current JRCALC and RCUK guidance. Paramedic-led RSI for OHCA remains a higher-skill, restricted intervention; SGA deployment should not be delayed waiting for a more qualified clinician when a CFR is on-scene.

Source: Huebinger R et al. Resuscitation 2026 (PMID 41812979)

LANCET · MAY 2026 · IPD META-ANALYSIS · PMID 42107392 · MCMASTER 6/7 · PHEM ANGLE

ATLAS IPD Meta-Analysis — PHEM Implications: Bypass to Comprehensive Stroke Centre Regardless of Core Size; Refine LVO Identification Tools

SR/MA

CHANGE THIS MONTH

DipIMC/FIMC

The ATLAS IPD meta-analysis (Lancet 2026; PMID 42107392; also covered in EM Issue 14) demonstrated that EVT for large-core LVO stroke (ASPECTS 0–5 or core ≥50mL) is beneficial up to 24 hours — aOR 1.63 for functional independence, RR 0.65 for mortality. The PHEM-specific implications are distinct from the ED implications: (1) Prehospital LVO identification: CPSS (Cincinnati Prehospital Stroke Scale), RACE (Rapid Arterial Occlusion Evaluation), and FAST-ED are tools available to HEMS physicians and critical care paramedics. Large-core LVO strokes (severe FAST deficit, gaze deviation, dense hemiplegia) should trigger direct bypass to a CSC regardless of estimated scan findings — the ATLAS result means imaging-based decisions at the receiving hospital should no longer be used to exclude EVT. (2) Time is still brain: The 24-hour window applies to imaging-guided selection; the benefit diminishes with time and early prehospital activation remains critical. (3) Blood pressure management: Current JRCALC guidance: avoid aggressively lowering BP in suspected stroke during prehospital phase. For confirmed LVO with haemodynamic instability: maintain SBP ≥130 mmHg to preserve penumbral perfusion.

PHEM operational point: For any patient with FAST positive + features suggestive of LVO (eye deviation, severe unilateral deficit, NIHSS equivalent ≥6): (1) Pre-alert the CSC directly with LVO bypass code; (2) Do not delay at a non-EVT site; (3) Document time of symptom onset (or last known well time) precisely — this is the critical variable for the receiving EVT team. Do not rule out EVT based on patient age, perceived deficit severity, or estimated imaging findings.

Source: Sarraj A et al. Lancet 2026 — ATLAS IPD Meta-Analysis (PMID 42107392) · Also covered in EM Issue 14

SECTION 2 — UK & OFFICIAL BODIES

NICE · 27 MAY 2026 · GUIDELINE UPDATE · NG258 · PHEM RELEVANCE

NICE NG258 Anaphylaxis Update — PHEM Angle: Handover Documentation of AAI Administration, Two AAIs at Discharge, Observation Criteria for Transferred Patients

GUIDELINE CHANGE TONIGHT UK DipIMC/FIMC

NICE updated NG258 (Anaphylaxis) on 27 May 2026 (covered in detail in EM Issue 14 and anaesthetics newsletters). The PHEM-specific implications: (1) Prehospital AAI administration documentation: If a patient has self-administered one or both of their AAIs before HEMS/ambulance arrival, document this explicitly in your ATMIST handover and on the pre-alert. The receiving ED clinical team needs to know exactly how many doses have been given, timing, and clinical response to determine whether the patient falls into a “high-risk” observation category under the updated guidance. (2) Prehospital adrenaline use: JRCALC guidance for anaphylaxis — IM adrenaline 0.5 mg for adults, repeat at 5 minutes if no response. The updated NICE guidance does not change prehospital dosing. (3) Observation standards: Under the updated NG258 Rec 1.1.11, patients who required more than one adrenaline dose prehospitally, or who have asthma/respiratory comorbidity, or who reacted to a venom or food allergen with unknown threshold, require extended observation — document these features clearly on handover to trigger the appropriate observation pathway. (4) Discharge prescribing: Not a PHEM responsibility, but ensure your documentation of the event supports the ED prescribing team: two AAIs at discharge is the new standard.

Source: NICE NG258 — Anaphylaxis: Updated 27 May 2026

UKHSA · UPDATED 26 MAY 2026

Hantavirus MV Hondius — PHEM/First Responder Update: UK Contacts Completing Monitoring Period; Remain Alert in Unexplained Respiratory Emergencies

UK SAFETY

As of 28 May 2026, the MV Hondius Andes hantavirus outbreak is entering the closing phase for UK contacts. UK nationals repatriated from Ascension Island and the broader outbreak are approaching the end of the 40-day maximum incubation period. The HCID unit at Guy’s and St Thomas’ NHS Foundation Trust continues to manage at least one admitted case. PHEM-specific: for frontline ambulance crews, BASICS doctors, and HEMS physicians, the guidance for potential hantavirus presentations is unchanged: (1) Travel history from MV Hondius or endemic South American regions within 40 days; (2) Presentation: severe flu-like prodrome progressing to respiratory failure/ARDS picture; (3) If suspected: Level 3 PPE (FFP3, gown, gloves, apron, eye protection) during any aerosol-generating procedure; (4) Pre-alert the receiving HCID unit (Arrowe Park or GSTT) before arrival — do not transport to a standard hospital without HCID warning; (5) Notify UKHSA HPT immediately (0344 778 8990).

Source: UKHSA Hantavirus Rolling Update (updated to 26 May 2026)

MHRA · JUNE 2026

MHRA June 2026 — DSI/2026/003 Blood Transfusion Giving Set and DSI/2026/004 Allurion Gastric Balloon Both Remain Active

UK SAFETY

DSI/2026/003 (Blood Transfusion Giving Set): PHEM relevance limited (blood giving sets used in hospital), but relevant to critical care cars with onboard blood product administration capability. Confirm your onboard giving sets are specifically labelled for blood administration. Visual colour check alone is insufficient — always read the product label. DSI/2026/004 (Allurion Gastric Balloon): PHEM responders may encounter patients with an Allurion gastric balloon presenting with acute abdominal pain, obstruction, or shock. Patients typically will not volunteer its presence. If you encounter an acutely unwell bariatric patient with unexplained abdominal pain or peritonism: include Allurion balloon complication in your differential, document it on handover, and pre-alert surgical team at the receiving hospital.

Source: gov.uk/drug-device-alerts — June 2026

RCEM · APRIL 2026 (WIDELY IMPLEMENTED MAY) · CLINICAL GUIDELINE UPDATE

RCEM Acute Behavioural Disturbance Guideline Updated — No “Excited Delirium” Terminology, IM Ketamine or Droperidol First-Line, Prone Restraint Contraindicated

GUIDELINE CHANGE TONIGHT UK DipIMC/FIMC

RCEM published an updated Acute Behavioural Disturbance (ABD) guideline in April 2026 which has been widely briefed and implemented across UK EDs during May 2026. Three changes are directly relevant to PHEM teams who frequently manage ABD prehospitally and hand over to ED: (1) Terminology: “Excited delirium” is no longer a recognised diagnostic term in the UK — it has been removed from all RCEM guidance due to contested evidence base and concerns about its forensic use to explain restraint-associated deaths. Use “acute behavioural disturbance” or “severe agitation” in documentation and handover. (2) Pharmacological management: Intramuscular ketamine (4–6 mg/kg IM) or droperidol (10 mg IM) are recommended as first-line agents for rapid tranquillisation in severe ABD where oral medication is not possible or appropriate. The previous default of IM haloperidol + benzodiazepine is now second-line. (3) Restraint: Prone restraint is contraindicated in the RCEM guideline — consistent with Home Office and College of Policing guidance. PHEM teams working alongside police in ABD scenes should be aware of this and advocate accordingly. The PHEM implications are significant: IM ketamine for prehospital ABD is within scope for HEMS physicians and many critical care paramedics. This RCEM guideline provides the in-hospital reference standard that your handover team is now working to.

PHEM handover point: When handing over a patient who has received IM ketamine prehospitally for ABD, document explicitly: drug, dose, route, time, and clinical response. The receiving ED team needs this to assess cumulative sedation burden and to avoid inadvertent over-sedation with additional agents. Do not use “excited delirium” on any documentation — use “acute behavioural disturbance” or “severe/extreme agitation”.

Source: RCEM Acute Behavioural Disturbance Guideline (April 2026)

RESUSCITATION COUNCIL UK · MAY 2026

RCUK: New Prehospital-Specific OH-ALS Course (21 May 2026) & “Weakest Link” Post-Cardiac Arrest Report — Survival Chain Gaps

UK INFORMING DipIMC/FIMC

RCUK OH-ALS Course (launched 21 May 2026): RCUK has launched a bespoke Out-of-Hospital Advanced Life Support course designed specifically for prehospital clinicians, distinct from the standard ALS course. The OH-ALS course covers prehospital-specific scenarios including prolonged resuscitation, scene safety-integrated resuscitation, special circumstances (hypothermia, drowning, electrocution, pregnancy), and HEMS physician-led OHCA management. UK PHEM relevance: this is the first nationally standardised RCUK course tailored to the prehospital environment. HEMS services and critical care paramedic programmes should evaluate whether OH-ALS replaces or complements ALS in their training matrices. RCUK “Weakest Link” Report (May 2026): A landmark RCUK report identifying the most common failure points in post-cardiac arrest survival chains across UK services. Key prehospital findings: (1) time to first defibrillation remains too long in witnessed VF; (2) post-ROSC temperature management is inconsistently applied; (3) handover of arrest-to-ROSC intervals and prehospital drug history is frequently incomplete. The report calls for standardised HEMS-to-ED “post-arrest bundle” documentation. PHEM teams: review your post-ROSC handover documentation against the report recommendations.

Source: RCUK OH-ALS Course Launch & Weakest Link Report (May 2026)

AIR AMBULANCES UK · MAY 2026 · SECTOR ALERT

UK HEMS Jet Fuel Cost Crisis — 15+ Air Ambulance Charities Warning of Operational Risk From Doubled Aviation Fuel Costs

UK SAFETY

Air Ambulances UK has issued a sector-level warning that more than 15 UK HEMS charities are facing material operational risk from aviation jet fuel costs that have approximately doubled following disruption to global oil supply chains linked to the US-Israel/Iran conflict. East Anglian supply chains are rated “moderate risk” from June 2026 by the sector body. No UK HEMS service has suspended operations at time of writing, but at least three charities have indicated that current fuel cost trajectories, if unaddressed, would require reduction in flying hours, grounding of second aircraft at dual-helicopter bases, or suspension of night operations within 6–12 months without additional public or government funding. UK context: the vast majority of UK HEMS services are NHS-contracted but charity-funded for aircraft and operational costs. The NHS contributions typically cover clinical staffing but not aviation operating costs. DHSC has been briefed. PHEM clinicians should be aware of the funding landscape and the potential operational implications for service availability. This is not a guideline change — but it is the most operationally significant NHS HEMS system threat since the COVID-19 period.

Operational awareness: If your trust or critical care network uses HEMS tasking as part of major trauma or cardiac arrest pathways, confirm with your regional HEMS service whether tasking criteria or response times are affected. Consider contingency planning for scenarios where HEMS tasking may be delayed or unavailable, particularly for night operations.

Source: Air Ambulances UK — Operational Fuel Cost Alert, May 2026

SECTION 3 — FOAMED & OPERATIONAL

ONSCENE ECPR TRIAL · NETHERLANDS · RESULTS EXPECTED Q3 2026

OnScene ECPR Trial — Enrolment Complete (n=220); Results Expected Q3 2026: The Definitive Prehospital ECPR RCT

INFORMING DipIMC/FIMC

The OnScene trial (Netherlands nationwide HEMS ECPR RCT) has completed enrolment with n=220 refractory OHCA patients randomised to on-scene ECMO-CPR vs standard ACLS. This is the only adequately powered RCT ever conducted on prehospital ECPR. Results are expected Q3 2026. The trial will definitively answer whether prehospital ECPR, as delivered by a mature nationwide HEMS system with appropriately trained physicians, improves neurologically intact survival compared to standard prehospital cardiac arrest management. UK context: the Sub30 London prehospital ECPR programme (covered in PHEM Issue 3) provides early observational data suggesting comparable outcomes to in-hospital ECPR. The OnScene result will either validate the concept for structured implementation in the UK or close the chapter on prehospital ECPR for the foreseeable future. Watch this space — it is the most anticipated PHEM trial result of 2026.

Source: onscenetrial.com · Carry-over from PHEM Issue 4

JOURNALFEED EM / CRITICAL CARE REVIEWS · MAY–JUNE 2026

This Month in PHEM FOAMed — TXA Bolus+Drip Dose Paradox; Whole Blood Synthesis; JEMS IPMI Literature Review May 2026

INFORMING

TXA Bolus + Infusion Dose Question (JournalFeed, 1 June 2026): A forthcoming analysis examining whether the maintenance infusion component of TXA dosing (1g over 8h) adds incremental benefit over the initial bolus alone. UK context: JRCALC guidance prescribes 1g IV bolus prehospitally; the infusion is an in-hospital continuation. No evidence supports prehospital infusion initiation over bolus alone in current protocols. JEMS IPMI May 2026 Literature Review: Covers SWiFT, TOWAR, tourniquet use in penetrating urban trauma (no mortality benefit of tourniquet in absence of vascular injury in this study — cautionary note for routine tourniquet application in all penetrating extremity trauma), i-gel SGA in the prehospital setting (88% first-pass success in one series). Critical Care Reviews: TOWAR trial critique published simultaneously with trial; notes the 2:1 randomisation (WB:component) means fewer patients in the component arm and potential underpowering for subgroup analyses.

Source: JournalFeed EM (1 June 2026) · JEMS IPMI Literature Review May 2026

QUICK HITS

Resuscitation · 2026 · Registry Analysis · n=107,548 · JournalFeed 1 June 2026 CPR Feedback Devices in OHCA — German Registry: Associated With Improved ROSC But Used in Only a Fraction of Cases Breuer-Kaiser et al (Resuscitation 2026) analysed 107,548 OHCA cases in a German EMS registry. CPR feedback device use was associated with modestly improved ROSC rates, but was used in a small minority of cases. UK PHEM relevance: feedback devices (e.g. Laerdal CPRmeter, Zoll AED Plus with feedback, LUCAS with real-time feedback) are standard on many UK critical care cars and HEMS platforms. Regular simulation and debriefing using feedback device data is strongly recommended. Where feedback devices are available, activation and compliance monitoring should be a governance metric. Paediatric Emergency Care · 2026 · Cross-Sectional · PMID 41875342 Prehospital Neonatal Resuscitation — EMS Outcome Data: 10% Survival, Highlights Critical Training Gaps Peters GA et al (Pediatric Emergency Care 2026) analysed EMS-managed neonatal cardiac arrests within the first 6 hours of life across a national database. Overall survival was 10%. Intervention success rates were highly variable across EMS systems. PHEM relevance: neonatal resuscitation remains one of the highest-stress, lowest-frequency prehospital scenarios. JRCALC neonatal guidance mandates BVM + warming; umbilical vein access is within scope for HEMS physicians. Regular neonatal simulation is a PHEM training requirement. If your HEMS or critical care car does not run regular NLS-aligned prehospital neonatal simulation, this is a training gap. PMID 41875342 Scand J Trauma Resusc Emerg Med · May 2026 · PMID 42218532 Prehospital Emergency Physicians in Paediatric Emergencies — Self-Perceived Competency Gaps: Procedural Skills and Drug Dosing Kamphausen A et al (SJTREM 2026; PMID 42218532) surveyed prehospital emergency physicians on their entrustable professional activities and competency perceptions in paediatric emergencies. Common self-perceived gaps: weight-based drug dosing under stress, paediatric airway sizing, and neonatal resuscitation. UK relevance: this mirrors known gaps in UK HEMS physician and critical care paramedic training. Use of the Broselow tape, JRCALC paediatric drug calculator, or dedicated apps is recommended. Structured paediatric scenario training should form part of annual HEMS and critical care car recertification.

CORE REVISION — PREHOSPITAL RSI: DRUGS, SEQUENCE, AND THE PERI-INTUBATION CRASH

DIPIMC/FIMC REVISION — PREHOSPITAL RAPID SEQUENCE INTUBATION

CICO + rocuronium: sugammadex 16 mg/kg IV immediately. DAS 4th edition (2024) is the UK standard. Draw up before every RSI with rocuronium.

ACTION POINTS — PHEM JUNE 2026

• Prehospital blood — both forms are valid: TOWAR + SWiFT confirm whole blood and component therapy are equivalent. Carry and administer whatever form your service has resourced. If your service does not carry prehospital blood products, use these two NEJM trials as evidence to advocate for implementation. [TOWAR PMID 42150044; SWiFT PMID 41841706]
• TXA — administer without hesitation: Prehospital TXA in haemorrhagic trauma does not increase thrombotic events. PATCH + STAAMP + ROC combined analysis is definitive. Administer 1g IV/IO bolus within 3 hours of injury. [Brito AMP et al, PMID 42023936]
• Balanced resuscitation in TBI: For polytrauma patients with moderate or severe TBI requiring any blood products: prioritise balanced plasma:RBC resuscitation (aim 1:1 ratio). Do not administer RBCs alone in TBI unless plasma is genuinely unavailable. Maintain MAP ≥80 mmHg. [Liu H et al, PMID 42023940]
• LVO stroke prehospital bypass: For FAST-positive patients with suspected LVO features (gaze deviation, dense unilateral deficit, NIHSS equivalent ≥6): bypass directly to CSC regardless of estimated imaging. ATLAS confirms no large-core LVO should be excluded from EVT consideration based on core size alone. Document time of last known well precisely. [ATLAS PMID 42107392]
• Anaphylaxis handover documentation: For any patient who has self-administered or been given prehospital adrenaline for anaphylaxis, document clearly: number of doses, timing, and clinical response. Patients who received multiple doses or have asthma/respiratory comorbidity require extended observation under updated NICE NG258 — this must be explicit in your ATMIST pre-alert. [NICE NG258, 27 May 2026]
• Hantavirus — HCID awareness for PHEM responders: Any patient with severe unexplained respiratory failure + travel history including MV Hondius or South America within 40 days: apply Level 3 PPE before all AGPs, pre-alert HCID-capable receiving unit, notify UKHSA HPT (0344 778 8990). Do not transport to non-HCID hospital without specialist advice. [UKHSA, updated 26 May 2026]
• Allurion gastric balloon — bariatric differential: In any acutely unwell bariatric patient with abdominal pain, unexplained obstruction, or peritonism: ask directly “have you had a weight-loss balloon placed in the last 6 months?” Document and pre-alert surgical team at receiving hospital. [MHRA DSI/2026/004]
• RCEM ABD guideline — update documentation and practice tonight: (1) Remove “excited delirium” from all prehospital documentation, clinical notes, and verbal handovers — use “acute behavioural disturbance” or “severe agitation” instead. (2) For severe ABD requiring pharmacological intervention: IM ketamine (4–6 mg/kg) or droperidol (10 mg IM) are first-line where within scope. (3) Prone restraint is contraindicated — advocate for positional change when working alongside police. (4) Document all prehospital sedation clearly on ATMIST: drug, dose, route, time, response. [RCEM ABD Guideline, April 2026]
• HEMS fuel crisis — check your contingency plans: Contact your regional HEMS service to understand whether operational constraints are anticipated, particularly for night operations. If your trust major trauma or cardiac arrest activation protocols default to HEMS availability, ensure a contingency for scenarios where HEMS is delayed or unavailable. Raise awareness at your critical care network governance level. [Air Ambulances UK, May 2026]
• Paediatric training gaps: If your HEMS or critical care car does not run regular paediatric simulation covering weight-based drug dosing, paediatric airway management, and neonatal resuscitation, this is a governance priority. Use the Broselow tape and JRCALC app to support weight-based prescribing under stress. [SJTREM 2026, PMID 42218532]

TRIALS TO WATCH

Upcoming Trials & Milestones Q3 2026 — Highest Priority OnScene Trial (Netherlands) — Prehospital ECPR RCT: n=220, enrolment complete. Results expected Q3 2026. The most consequential prehospital trial result of 2026 for advanced HEMS systems. A positive result will accelerate UK ECPR service development; a negative result will reframe the entire field. PRINCESS2 Main Trial — Prehospital Brain Cooling: Following the successful PRINCESS2 pilot (n=100; covered PHEM Issue 3), the main trial is enrolling. Prehospital trans-nasal evaporative cooling for OHCA. Results likely 2027+. 2026–2027 PARAMEDIC-4 (anticipated) — Calcium in Prehospital OHCA: Following the high-impact calcium chloride in massive transfusion data (EM Issue 14 Quick Hits) and ionised calcium literature, a dedicated prehospital cardiac arrest calcium trial is being discussed in the UK resus community. Watch for protocol publication. EAST REBOA Practice Management Guideline 2025 — UK Uptake: The EAST 2025 PMG conditionally recommends REBOA for traumatic cardiac arrest with suspected subdiaphragmatic bleeding. UK implementation via specialist HEMS teams (London, Midlands Ambulance, MERIT) continues. Monitor for publication of UK REBOA registry data and national guideline development from FPHC/RCSEd. CoMiTED — Conservative vs Immediate Chest Drain in Traumatic Pneumothorax (UK): Ongoing. Will directly inform UK prehospital and ED chest trauma management guidelines. PHEM teams providing needle thoracostomy and finger thoracostomy will be directly affected. BACHb — HFNC vs CPAP vs Standard O2 in Bronchiolitis (50 NHS hospitals): Not PHEM-primary but relevant to paediatric critical care transport. Results will inform HEMS physician respiratory support choices for infant bronchiolitis transfers. Longer Horizon HSSIB Mental Health Crisis Care Part 2 (summer 2026): Will address ED environment and inter-agency response to mental health crises in urgent care. Prehospital mental health crisis presentations are frequent; PHEM teams operate at the interface between S136 suite, HEMS, and community response. Watch for recommendations on joint PHEM/MH working. EAST Whole Blood Next Steps — Multi-Centre RCT Phase 2: Both SWiFT and TOWAR were “type and quantity” equivalence trials. The next important question is not WB vs component but blood vs no-blood vs crystalloid as a randomised comparison. Forthcoming trials will attempt to close this gap.

Jake Turner Curated with the assistance of AI (Perplexity). All content editorially reviewed. PHEM Evidence Rundown — June 2026 — Issue 5 — UK Edition Published by EM Evidence. For clinical use only — verify against local guidelines before implementing changes in practice. Feedback form · emevidence.org · emevidence999@gmail.com