(12C) Body Surface Area

[Gamo]

This program should be useful for nursing and medical stuff to measure BSA

Program is adapted from HP-46 Sample Applications Section Medicine Page 66

The calculation is from the formula of DuBois D, DuBois EF. 1916
A formula to estimate the approximate surface area if height and weight be known.

Formula: LogA = (0.425 LogW) + (0.725 LogH) - 2.144

A = Body Surface Area in m²
W = Weight in kg.
H = Height in cm.

Weight - 4 kg.
Height - 35 cm.

[ BSA (Child) = 0.170 m² ]

Steps: W [R/S] H [R/S] display A in m²

Program:

Code:


01    LN
02    1
03    0
04    LN
05    STO 0    // Store Log Base Constant
06    ÷
07    STO 1   // Store LogW
08    R/S
09    LN
10    RCL 0
11    ÷
12    .
13    7
14    2
15    5
16    x     // Calculate (0.725 LogH)
17    RCL 1
18    .     // Decimal Point
19    4
20    2
21    5
22    x    // Calculate (0.425 LogW)
23    +   // Add both side together
24    2
25    .    // Decimal Point
26    1
27    4
28    4
29    -    // Subtraction Sign
30    1
31    0
32    X<>Y
33     Y^X    // Calculate LogA
34    GTO 00

Remark:
Today the easiest to calculate and remember is the Mosteller Formula by
taking the square root of the height (cm) mutiplied by the weight (kg) divided by 3600

BSA (m²) = √[ ( height x weight ) ÷ 3600 ]

The answer result accuracy from this formula almost comparible from DuBois formula.

Extra Examples:

What is the BSA for Mr. Joe weighing 210 pounds with a height of 6 feet, 3 inches?

►Calculate weight in kilograms: 210 pounds ÷ 2.2 = 95.45 kg

►Calculate height in centimeters: 6 feet, 3 inches = 75 inches x 2.54 cm/inch = 190.5 cm

95.45 [R/S] 190.5 [R/S] Display Result 2.24 m²


Gamo 7/2021