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What is Body Surface Area? (Free Downloadable Guide)

What is Body Surface Area? (Free Guide)

As the leading provider of medical scales to NHS hospitals, we are always updating our range of weighing scales to meet the needs of the medical industry. This is why we’ve added a Body Surface Area (BSA) function to our latest range of weighing scales.

Lack and Taylor have said, “BSA is recommended as the principal basis for drug dosages,” which has been backed by other studies.

But why is it used for this purpose? What else can it be used for? How is it calculated, and how can you work it out? All is revealed in our new, free guide, which you can download at the end of this blog post.



Why is BSA used?

BSA has been regarded as “the most reliable method of calculating drug dosages… for nearly 90 years,” according to the British National Formulary.

This is due to its proportionality with metabolic rate, which in turn reflects heat losses which are generally proportional to surface area.

Plus, many measurements of organ size, fluid compartment volumes and assays of blood concentration of drugs, correlate well with BSA.



What is BSA used for?

BSA is used for calculating medication dosages, in chemotherapy, for calculating burns and more. The general rule for medication doses is, the larger the body surface area, the greater the dose.

Calculating medication in obese patients should also be worked out by using BSA, however experts suggest this is not the case. Dr Caterina Fontanella said, “It is a very common practice in these patients for fear of overdosing, but of course it means that they will often receive a relatively lower quantity of chemotherapy.”

For more information on suitable situations for using body surface area, download the white paper below.



How can you use a weighing scale to calculate it?

You can calculate BSA on any I-300 weighing scale.

To use the function on the M-125, M-225 and M-545, follow the steps below:

  1. Stand/sit on the scale.
  2. Hold down the HOLD/BMI button.
  3. Enter the height by using the TARE/BSA, HOLD/BMI and SEND. To confirm the height press ON/ZERO/OFF.
  4. Weight, height and BMI will display on screen.
  5. Press TARE/BSA and Body Surface Area will be displayed.

The Marsden M-125: Our latest column scale boasts our new BSA function. The base is fitted with wheels for easy transportation between rooms. It also features Hold, Tare and BMI.

The Marsden M-225: This lightweight chair scale is perfect for hospitals and care homes. It has a 250kg capacity and accuracy to the nearest 100g. It is safe and comfortable with hinged armrests and footrests, and two fitted brakes.

The Marsden M-545: This floor scale is ideal for GP surgeries and clinics. It features a remote indicator to keep sensitive weight readings private. Plus the scale is lightweight, is powered by 6x AA batteries and has an optional carry case for extra portability.


For more information on how to use BSA, call 01709 364296 or contact us here. Download the BSA guide.