Different demands from a reference work
An emergency app for doctors is rarely used at a desk. Typical situations are an ongoing resuscitation, a sick child on the stretcher or unexpected haemodynamic instability during induction of anaesthesia. The setting is hectic, the lighting is often poor and interruptions are frequent. An emergency app for doctors must therefore meet two goals at once: it must be fast, and every number it displays must remain traceable to its source.
The following criteria can help you critically assess a prehospital emergency physician app or a digital compendium before using it in practice.
1. Weight-based dosing: make the calculation visible
Weight-adjusted doses are particularly prone to error in paediatric emergency medicine. A usable app therefore shows not only the result but also the calculation steps:
- Dose per kg with unit, i.e. mg/kg or µg/kg
- Maximum dose that must not be exceeded
- Concentration of the prepared solution, including dilution
- Volume in ml actually administered
Example: paediatric resuscitation
According to the ERC Guidelines 2025 (Paediatric Life Support), the dose of adrenaline (epinephrine) is 0.01 mg/kg (10 µg/kg) i.v./i.o., maximum 1 mg, every 4 minutes. When diluted to 0.1 mg/ml (1 mg made up to 10 ml with NaCl 0.9 %), 10 µg/kg corresponds exactly to 0.1 ml/kg. A child weighing 20 kg therefore receives 0.2 mg, i.e. 2 ml. In non-shockable rhythms, adrenaline is given as early as possible (within 3 min); in shockable rhythms, after the 3rd and 5th shock and every 4 minutes thereafter.
For amiodarone in VF/pVT, the same guideline specifies 5 mg/kg i.v./i.o. after the 3rd shock, maximum 300 mg. The 2nd dose is given after the 5th shock and is then limited to a maximum of 150 mg. This illustrates the additional information an app should provide: according to the product information, amiodarone preparations containing benzyl alcohol are contraindicated in neonates, infants and children up to 3 years of age. The preparation used should therefore be checked.
Not every dose is based on body weight
An emergency app should also cover other reference parameters. One example is hydrocortisone in adrenal crisis in children: 50 mg/m² body surface area (max. 100 mg) i.v. or i.m. as a bolus, according to the Endocrine Society guideline (2016). This requires a stored formula for calculating body surface area, and the formula used must be clearly stated.
Limitations of calculated values
Calculators simply convert the values entered according to the formulae specified. They do not make a diagnosis, do not replace the decision on indication and do not remove the need to check the result. Tabulated values apply to typical patients. Individual adjustments are required in obesity, cachexia, organ failure, pregnancy, advanced age and in preterm and term neonates. A reputable app states these limitations explicitly.
2. Concentration and preparation as a source of error
Many dosing errors arise not during calculation but when converting mg into ml. Concentrations of commercial preparations differ between manufacturers and countries. A prehospital emergency physician app should therefore state the underlying concentration for every dose.
Lidocaine is a typical example. Both 1 % and 2 % solutions are commercially available. At 2 % (20 mg/ml), 100 mg corresponds to 5 ml; at 1 % (10 mg/ml), it corresponds to 10 ml. According to the summary version of the ERC Guidelines 2025, lidocaine is an alternative to amiodarone in refractory or recurrent VF/pVT: 100 mg i.v./i.o. after the 3rd shock and 50 mg after the 5th shock. Lidocaine is used only if amiodarone is unavailable or if this has been determined locally, and it is not combined with amiodarone. Only solutions without added adrenaline are suitable for antiarrhythmic use.
With dry powders, too, the result depends on the preparation. Hydrocortisone 100 mg dissolved in 2 ml gives 50 mg/ml. However, the solvent volume must be checked for each preparation.
3. A source for every single dose
A general statement such as "according to current guidelines" is not sufficient. Each individual dosing recommendation should be linked to its specific source: the guideline with year and citation, or the relevant summary of product characteristics. Only then can it be quickly clarified, in case of doubt, whether a recommendation is based on a guideline, a marketing authorisation or expert consensus. Off-label information must be labelled as such.
A transparent correction process is equally important. Medicine continues to evolve, and errors can never be entirely ruled out despite careful review. Users should be able to report errors, and corrections should be incorporated into new versions in a traceable way. It is also helpful to disclose the editorial review and approval status of individual chapters.
4. State guideline status transparently
Within a single app, the guideline status may differ from topic to topic. The ERC Guidelines 2025 apply to resuscitation. Other indications are based on older or different guidelines. Taking hydrocortisone as an example:
- Adrenal crisis in adults: 100 mg i.v. or i.m. as a bolus, followed by 200 mg/24 h. The source is the joint guideline of the European Society of Endocrinology and the Endocrine Society (2024).
- Adrenal crisis in children: Endocrine Society (2016).
- Septic shock with ongoing vasopressor requirement: 200 mg/24 h i.v. according to the Surviving Sepsis Campaign (2021). To be considered when noradrenaline (norepinephrine) ≥ 0.25 µg/kg/min is required for at least 4 hours.
An emergency app for doctors should clearly state the status of each recommendation as well as the version of the app itself. For assessment purposes, the currency of an individual recommendation is more informative than a general update date.
5. Offline availability and reliability
In basements, helicopters, rural valleys or shielded operating theatre areas, network reception is often unreliable. Before use, you should therefore clarify:
- Do content and calculators work without a network connection, and to what extent?
- How can you tell whether the locally stored version is up to date?
- What happens if the battery runs out or the device fails?
Regardless of the technology, an analogue fallback is advisable, such as a printed summary or local emergency tables. In paediatric resuscitation in particular, a readily available table with weight, dose and volume is a proven backup.
6. Austrian and German versions, local requirements
Emergency physicians and anaesthesia teams in German-speaking countries work with differing drug availability, preparation concentrations and regulations on scope of practice. An app for Austria and Germany should therefore make clear which summary of product characteristics a recommendation refers to. It should also point out that preparations may differ between countries.
Irrespective of this, local requirements take precedence. These include SOPs, care pathways, scope-of-practice regulations and the drug formularies of the institution or emergency medical service. An app supplements these requirements but does not replace them. The lidocaine example illustrates this: whether lidocaine is used instead of amiodarone may be determined locally.
7. Usability under stress
- Few steps to the dose: the key information for resuscitation should be accessible without lengthy navigation.
- Easy to read: large numbers, unambiguous units (mg and µg clearly distinguishable), consistent decimal separator.
- No ambiguity: route of administration, interval and maximum dose are shown directly with the dose.
- Warnings in context: contraindications and preparation notes appear where the dose is given.
Selection checklist
- Is a specific source given for every dose?
- Are concentration, dilution and volume in ml stated?
- Are maximum doses and off-label information labelled?
- Is the guideline status recognisable for each topic, i.e. ERC 2025 for resuscitation?
- Is it clear what works without a network, and is there an analogue fallback?
- Are the limitations of the calculators and the precedence of local SOPs stated?
- Is there a traceable way to report errors?
Context
"Notfall & Narkose" is edited by Dr. med. univ. Daniel Pehböck, DESA, specialist in anaesthesiology and intensive care medicine and emergency physician in Tyrol. The provider is PL Simulation Tirol GmbH. The compendium is available as a web app (free section, full access by subscription) and as a printed A6 pocket book. It is intended for healthcare professionals. The criteria above apply equally to every emergency app, including this one.
References
- Djakow J, Turner NM, Skellett S et al. European Resuscitation Council Guidelines 2025 Paediatric Life Support. Resuscitation 2025;215 Suppl 1:110767.
- Kurzfassung der Leitlinien des European Resuscitation Council 2025. Notfall Rettungsmed 2025.
- Beuschlein F et al. European Society of Endocrinology and Endocrine Society Joint Clinical Guideline: Diagnosis and therapy of glucocorticoid-induced adrenal insufficiency. Eur J Endocrinol 2024;190:G25–G51.
- Bornstein SR et al. Diagnosis and Treatment of Primary Adrenal Insufficiency: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab 2016;101:364–389.
- Evans L et al. Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock 2021. Intensive Care Med 2021;47:1181–1247.
This article does not replace clinical judgement in the individual case or the current summary of product characteristics and guidelines.
