Heval: the human evaluator. Calculate what your human crave!

Heval is available as a web app https://radioxoma.github.io/heval/

Heval is a medical calculator for intensive care unit. Main features:

Minimal user input — unknown values estimated automatically whenever possible (e.g. weight by height)
Only measurable parameters — no need to speak with a human of interest
No "Calculate" button — evaluated data changes immediately with your input
Every calculation referenced and explained in source code, so everyone can reproduce it
Python package can be integrated into medical information system
It's got electrolytes

Usage

From just sex and height it evaluates IBW, BSA, fluid, nutrition and respiratory demands, urinary output, dialysis dose and more. ABG interpreter reveals hidden processes, suggests urgent correction measures and infusion therapy. There are overwhelming amount of spinboxes, but filling them all is not required.

Human body

Tip: Get yourself a ruler, not all humans are able to talk.

Just enter sex and height. That's it! Age, even for children, is not mandatory because it has poor prediction power. Incorporated Broselow-Luten color zones and weight-by-height formulas at your service.

Laboratory

Tip: You can test Heval's ability to interpret ABG with case studies. Some books provide case studies with invalid data (see below).

Requires some bloodwork to be done. Take arterial blood gas sample whenever possible.

Enter pH and pCO2 for simplest acid-base status assessment
Enter electrolytes to reveal hidden processes (anion gap, delta-gap) and general electrolyte disturbances
- Algorithm able to detect mixed acid-base disorders, vomiting etc
- Hi-low electrolytes correction strategies
- Tips for emergency cases
- Sex and weight used only for dosage calculations, not for ABG diagnostics itself
Enter optional data for complex cases
- Albumin, if there is metabolic acidosis - for anion gap correction
- DKE/HHS
- Hyperosmolar pseudohyponatremia estimation

Validation

Please use a real patient's data: all electrolytes interconnected by electroneutrality law, Henderson-Hasselbalch equation. So even if you enter values in reference range, calculations can produce a broken result, especially anion gap (e.g. 149 - (101 + 24) = 24 which is >16 mEq/L!). Some imagined case studies from books aren't designed well and will fail too.

Disclaimer

Heval is an experimental software. Whatever it calculates, it's your decisions will affect your human's live longevity. I have no responsibility for your collateral damage.

Key: Garbage -> Limited -> Medium -> Good -> Excellent

| Function | Status | Comment | |------------------------------------------------------------------|-----------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | Human body: anthropometry | Good | Straightforward implementation. Broselow for children. | | Human body: respiration | Good | Use as start ventilator settings for adults and children | | Human body: energy & electrolytes | Limited | Generic approximation for healthy human. Real demands are unpredictably dependent on body fat/muscle compound, fever, sepsis, burns etc. REE formulas has been taken from original papers, so your lovely Harris-Benedict equation don't have dubious correction coefficients, leading to irreproducible result. | | Human body: fluid demand | Limited | Generic approximation for healthy human. Pathologic fluid loss must be taken into account | | Human body: urinary output | Good | Simple ml/kg/h approach for adults and children, though eGFR estimation may be necessary | | Nutrition | Limited | Enteral and parenteral. Based on ESPEN 25-30 kcal/kg recommendation and nitrogen balance. Use indirect calorimetry if you need a real tool. | | ABG: pH correction | Limited | Recent papers deny benefit from iv bicarbonate if BE <-15 mEq/L. Mortality decrease is possible in AKI patients. No validated formula found. | | ABG: anion gap | Good | Excellent prediction, but please USE REAL DATA | | ABG: Electrolytes replacement | Limited | Exact depletion/excess estimation is impossible due to multiple body compartments. High/low warnings still usable though. K+ — no reliable model, use daily requirement and standard iv replacement rate for hypokalemia. Na+ — Adrogue and classic one compartment model. Cl- — no model at all. Multiple calculation methods in books, few applicable in real world. | | eGFR | Good | Straightforward implementation. Cockcroft-Gault, CKD-EPI 2021 for adults, Schwartz revised 2009 for children. |

Installation

Since 2026 development switched towards web app. Desktop app is obsolete.

Windows

Download exe file from the releases page. Just run it — installation is not required.

v0.1.5 is last compatible with Windows XP SP3 x86 and python 3.4.3.
Latest version can be installed wit

Heval

Install / Use

README