Blood Volume Loss Estimator

How the blood volume loss estimator works

Total blood volume is estimated from body weight, conventionally 70 mL per kilogram in an adult and higher in children and neonates. A pool's volume follows from its dimensions, treating it as a shallow slab, since one cubic centimetre is one millilitre.

The result is expressed against the ATLS haemorrhage classes so the figure has clinical context, but a pool is a poor proxy for blood actually lost.

Frequently asked questions

How much blood is in the human body?

About 70 mL per kilogram of body weight in an adult, so roughly 5 litres for a 70 kg person. Children run higher per kilogram, around 80 mL/kg, and neonates around 85 mL/kg.

Can blood loss be determined from a crime scene pool?

Not reliably. Blood soaks into flooring, textiles and clothing, dries and contracts, and spreads differently on every surface. A pool gives an order of magnitude at best and is never a medical determination.

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