⚠️Calculated upper ceiling — not a recommended dose. Use the lowest effective dose. LAST is an emergency (lipid emulsion). Values pending clinical review.
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1 · Patient
▸ Risk factors (adjust warnings)
Enter age, sex, height & weight.
2 · Drug & concentration
3 · Procedure / block
4 · Previous / second agent (optional)
⚠️ LAST is an emergency
Stop injecting · call for help · get the lipid emulsion (Intralipid 20%) kit · prepare for prolonged resuscitation.
1 Immediate management
Stop injecting local anaesthetic. Call for help & the LAST/lipid kit.
Seizures: a benzodiazepine is preferred (e.g. midazolam). Avoid large-dose propofol if haemodynamically unstable.
Alert the nearest facility with cardiopulmonary bypass / ECMO early.
2 Lipid emulsion 20% — ASRA 2020 & AAGBI 2010
3 If cardiac arrest / instability (modified ACLS)
Reduce adrenaline (epinephrine) to small boluses ≤ 1 µg/kg — far below the standard 1 mg ACLS dose.
Treat arrhythmias with amiodarone. Continue lipid emulsion alongside CPR.
Cardiac arrest may be refractory — continue resuscitation for >1 hour; consider CPB/ECMO.
✗ Avoid in LAST
Vasopressin
Calcium-channel blockers & beta-blockers
Further local anaesthetic (incl. lidocaine as antiarrhythmic)
Large-dose adrenaline & large-dose propofol
4 After the event
Continue the lipid infusion for at least 10–15 min after circulatory stability.
Monitor at least 2 h after a limited CNS event, and 4–6 h after any cardiovascular event.
Report to your local registry (e.g. www.lipidrescue.org).
Based on the ASRA 2020 Practice Advisory / LAST Checklist (Neal, Neal & Weinberg) and the AAGBI / Association of Anaesthetists 2010 safety guideline. Doses are 20% lipid emulsion. Educational aid — follow your institutional protocol and product information. Reviewed Jul 2026.
Method: LBW by Janmahasatian; IBW by Devine; adjusted = IBW+0.4(TBW−IBW). Auto dosing weight: TBW if BMI<30, LBW if BMI≥30 (prominent caution ≥40); children use actual weight (paediatric-obesity needs a specialist protocol). Systemic ceiling = min(weight-based, absolute, cumulative) − previous exposure. Combined additive fraction ≤1.0. The maximum is a ceiling, never the recommended procedural dose.
Drug maxima & block ranges are a curated starter set pending clinical review. Sources: BNF/BNFc; ASRA LAST guidance & regional-anaesthesia references; product information. Confirm every value locally before use.
