Why adrenaline in cardiac arrest?
Adrenaline (INN: epinephrine) is a catecholamine with α- and β-sympathomimetic activity. In resuscitation, the main effect is α-mediated vasoconstriction, which is intended to improve perfusion pressure during chest compressions. The ERC 2025 guidelines continue to recommend adrenaline as the standard drug in advanced life support for adults and children.
The evidence for a benefit in survival with a favourable neurological outcome is considered more limited than for return of spontaneous circulation. This underlines the hierarchy of interventions: high-quality chest compressions with minimal interruptions and early defibrillation in shockable rhythms take priority. Adrenaline supplements these measures but does not replace them.
Preparation: two concentrations, two areas of use
Two concentrations are commonly used in emergencies:
- 1 mg/ml (1 ml = 1 mg), undiluted from the ampoule
- 0.1 mg/ml, prepared from 1 mg made up to 10 ml with NaCl 0.9 %
In adult resuscitation, the undiluted solution is usually used. In children, dilution to 0.1 mg/ml forms the basis of weight-based dosing, giving a simple volume of 0.1 ml/kg.
Adrenaline dose in adult resuscitation (ERC 2025)
According to the ERC 2025 guidelines for adult advanced life support:
- Dose: 1 mg IV/IO
- Volume: 1 ml of the 1 mg/ml solution
- Repeat: every 3–5 min
Timing by rhythm
- Non-shockable rhythm (asystole, PEA): give adrenaline as early as possible once IV or IO access is available.
- Shockable rhythm (VF/pVT): first dose after the 3rd shock, then every 3–5 min.
The different timing follows the logic of the algorithm. In shockable rhythms, early defibrillation takes priority and adrenaline is added only after the first shocks. In non-shockable rhythms this option does not exist, so the vasopressor is given at the earliest opportunity.
Adrenaline in paediatric resuscitation: weight-based dosing
For children, the ERC 2025 Paediatric Life Support guidelines specify weight-based dosing:
- Dose: 0.01 mg/kg (10 µg/kg) IV/IO
- Maximum single dose: 1 mg
- Concentration: 0.1 mg/ml (1 mg made up to 10 ml with NaCl 0.9 %)
- Volume: 0.1 ml/kg of the dilution
- Repeat: every 4 min (every 2nd cycle)
Timing by rhythm in children
- Non-shockable rhythm: as early as possible, within 3 min.
- Shockable rhythm: after the 3rd and 5th shocks, then every 4 min.
The paediatric regimen therefore differs from the adult algorithm in two respects. The repeat interval is fixed at 4 min (every 2nd cycle). In addition, in shockable rhythms the first two doses are explicitly linked to the 3rd and 5th shocks.
Weight table (0.01 mg/kg, dilution 0.1 mg/ml)
| Body weight | Dose | Volume (0.1 mg/ml) |
|---|---|---|
| 3 kg | 0.03 mg | 0.3 ml |
| 5 kg | 0.05 mg | 0.5 ml |
| 10 kg | 0.1 mg | 1 ml |
| 15 kg | 0.15 mg | 1.5 ml |
| 20 kg | 0.2 mg | 2 ml |
| 25 kg | 0.25 mg | 2.5 ml |
| 30 kg | 0.3 mg | 3 ml |
| 40 kg | 0.4 mg | 4 ml |
The rule of thumb "0.1 ml/kg of the 1:10 dilution" allows quick mental calculation. However, it does not replace a spoken cross-check within the team. If body weight is unknown, it should be estimated using a locally established aid.
Adults and children compared
| Parameter | Adults | Children |
|---|---|---|
| Dose | 1 mg | 0.01 mg/kg (max. 1 mg) |
| Concentration | 1 mg/ml | 0.1 mg/ml |
| Interval | every 3–5 min | every 4 min (every 2nd cycle) |
| Non-shockable | as early as possible | as early as possible (within 3 min) |
| Shockable | after the 3rd shock | after the 3rd and 5th shocks, then every 4 min |
Common sources of error in practice
Confusing concentrations
The greatest risk lies in confusing resuscitation and anaphylaxis dosing. In anaphylaxis, adrenaline is given intramuscularly and undiluted (1 mg/ml), at 0.01 mg/kg with a maximum of 0.5 mg per single dose (ERC 2025 PLS). In paediatric resuscitation, by contrast, it is given intravenously or intraosseously from the 0.1 mg/ml dilution.
The milligram dose per kilogram is the same in both situations, but the volume differs by a factor of 10. Syringes should therefore be clearly labelled with drug and concentration. An instruction should always include the dose in mg, the concentration and the volume, for example "0.2 mg adrenaline, that is 2 ml of the 0.1 mg/ml dilution".
If anaphylaxis progresses to cardiac arrest, the resuscitation algorithm with IV/IO dosing applies.
Incompatibility with alkaline solutions
Adrenaline loses efficacy when mixed with alkaline solutions such as sodium bicarbonate. If both drugs are given via the same line, it must be flushed in between.
Time management
The intervals of 3–5 min in adults and 4 min in children can only be maintained with structured timekeeping. The following have proven useful:
- a designated person for drugs and documentation,
- a running timer,
- announcing the next adrenaline dose in step with the analysis cycles.
In children, linking doses to every second cycle aids orientation.
Contraindications and adverse effects
In cardiac arrest there are no absolute contraindications to adrenaline. After return of spontaneous circulation, the following effects may occur:
- tachycardia
- arrhythmias
- hypertension
- myocardial ischaemia
The post-ROSC phase therefore requires close monitoring.
Special case: local anaesthetic systemic toxicity (LAST)
In cardiac arrest due to local anaesthetic systemic toxicity, the ASRA checklist recommends giving adrenaline in reduced single doses (≤ 1 µg/kg). In addition:
- Use 20 % lipid emulsion as an antidote.
- Continue resuscitation for a prolonged period if necessary.
- Consider extracorporeal techniques (ECLS) early.
Here, dosing deliberately departs from the standard algorithm. The specific situation should be clearly stated within the team.
Pocket summary
- Adults: 1 mg IV/IO every 3–5 min. In non-shockable rhythms as early as possible, in shockable rhythms after the 3rd shock.
- Children: 0.01 mg/kg (max. 1 mg) IV/IO from the 0.1 mg/ml dilution, i.e. 0.1 ml/kg, every 4 min. In non-shockable rhythms within 3 min, in shockable rhythms after the 3rd and 5th shocks.
- Do not confuse concentrations: IM undiluted in anaphylaxis, IV/IO diluted in paediatric resuscitation.
- Flush the line; do not mix with sodium bicarbonate.
- Keep priorities: quality of chest compressions and early defibrillation before the drug.
The weight tables are also available in the "Notfall & Narkose" web app and in the pocket book. The current guideline and summary of product characteristics always remain authoritative.
References
- Soar J, Böttiger BW et al. European Resuscitation Council Guidelines 2025 Adult Advanced Life Support. Resuscitation 2025;215 Suppl 1:110769 (Korrigendum 2026).
- Djakow J, Turner NM, Skellett S et al. European Resuscitation Council Guidelines 2025 Paediatric Life Support. Resuscitation 2025;215 Suppl 1:110767.
- Neal JM, Neal EJ, Weinberg GL. American Society of Regional Anesthesia and Pain Medicine Local Anesthetic Systemic Toxicity checklist: 2020 version. Reg Anesth Pain Med 2021;46:81–82.
This article does not replace clinical judgement in the individual case or the current summary of product characteristics and guidelines.
