How does a physician estimate the volume of fluid lost in severely burned patient?

The Parkland formula is a method used by physicians to estimate the volume of fluid lost in severely burned patients. It is based on the patient's body weight and the percentage of body surface area that has been burned.

The formula is as follows:

```

4 mL x weight (kg) x % TBSA burned

```

For example, a 70 kg patient with a 20% TBSA burn would require approximately:

```

4 mL x 70 kg x 20% = 5600 mL

```

This would be the total amount of fluid needed to replace the fluid lost through the burn wound.

The Parkland formula is just an estimate, and the actual fluid needs of a burn patient may vary. However, it is a useful tool for helping physicians to quickly and accurately estimate the amount of fluid that is needed.

In addition to the Parkland formula, physicians may also use other methods to estimate fluid loss in burn patients, such as the Galveston formula or the Baxter formula.