1. Dimensional Analysis for Meds
Chapter 4

2. Chapter 4 Metric, International (SI) System
You do not need to know all of the System!
Much easier than English System
All units of measure differ from teach other in powers of ten (10).
Conversions between units in the system are accomplished by simply moving the decimal point.

3. English Lengths 12 inches = 1 foot 3 feet = 1 yard 5 ½ yards = 1 rod
40 rods = 1 furlong
8 furlongs = 1 mile

4. English Weights 27 11/32 grains = 1 dram 16 drams = 1 ounce
16 ounces = 1 pound
200 pounds = 1 ton

5. English Volumes 2 pints = 1 quart 4 quarts = 1 gallon
31 ½ gallows = 1 barrel
2 barrels = 1 hogshead

6. English Lengths 500 inches x 1 foot/12 inches = 41.67 feet
12 inches = 1 foot
3 feet = 1 yard
5 ½ yards = 1 rod
40 rods = 1 furlong
8 furlongs = 1 mile
If you have a piece of sting that is 500 inches long, how many feet is that? How many yards?
500 inches x 1 foot/12 inches = feet
500 in x 1 ft/12 in x 1 yrd/3 ft = yards

7. Metric System 3 Basic words It does not mater what prefix you have.
Meter = length
Gram = weight
Liter = volume
It does not mater what prefix you have.

8. Small Group Quiz! L = Length W = Weight V = Volume Milligram
Centimeter
Milliliter
Kilometer
Microgram
L = Length
W = Weight
V = Volume

9. Small Group Quiz! Milligram = (W) weight Centimeter = (L) length
Milliliter = (V) volume
Kilometer = (L) length
Microgram = (W) weight

10. Metric prefixes Same prefix for length, volume, weight. Kilogram
Kiloliter
Kilometer

11. Kilo Kilo Prefix Larger than basic by 1000 1 kilometer = 1000 meters
1 kilogram = 1000 grams
1 kiloliter = 1000 liters

12. 3 Prefixes (smaller than basic)
Centi – ( centimeter) 100x smaller than basic
Milli – (Millimeter) 1000x smaller than basic
Micro (microgram) 1,000,000x smaller than basic

13. 1 Kilometer = 1 meter = 1 millimeter = 1000 meters 1000 millimeters
1000 micrometer

14. 1 Kilogram = 1 gram = 1 milligram = 1000 gram 1000 milligram
1000 microgram

15. Kiloliter = 1 Liter = 1 milliliter = 1000 Liter 1000 milliliter
1000 microliter

16. Symbols Prefix Kilo = k Basic unit Centi = c Milli = m Micro = mc
Kiloliter = kL
Centi = c
Centimeter = cm
Milli = m
Millimeter = mm
Micro = mc
Microgram – mcg
Basic unit
Meter = m
Liter = L
Gram = g

17. Rules!
mL = cc
Do not chart
Microgram = mg

18. Small group Quiz Write the following in abbreviated form Microgram
Milliliter
Kilometer
Kilogram
Microliter
Centimeter

19. Small group Quiz Write the following in abbreviated form
Microgram = mcg
Milliliter = mL
Kilometer = km
Kilogram = kg
Microliter = mcL
Centimeter = cm

20. Metric System & Meds Weight Volume
Only use dosages that differ by 1000 units to the next measurement
Weight
Volume
1 kg = 1000 g
1 L = 1000 mL
1 g = 1000 mg
1 mg = 1000 mcg

21. Conversions between units
Conversion between units are accomplished by moving the decimal point!
How far? (How many places)?
How many “0” in 1000? 3
Move the decimal point 3 places

22. Conversions between units
Which direction do you move the decimal point?
IF large units to small units
The quantity (number) must get larger
Large  smaller
Move the decimal to the right
0.5 g = __?__ mg
g to mg is a difference of 1000 units
Kg g  mg  mcg
500 mg

23. Conversions between Units
2.5 L = __?__ mL
L to mL is a difference of 1000 units
L  mL
Large  small
2500 mL
500 mg = __?__ mcg
mg to mcg is a difference of 1000 units
Kg  g  mg  mcg
500,000 mcg

24. Small Group Practice 9 mg = ___?___ mcg 2.3 L = ___?___ mL
0.09 kg = ___?___ g
4.7 g = ___?___ mg
0.75 kg = ___?___ g

25. Small Group Practice 9 mg = 9000 mcg 2.3 L = 2300 mL 0.09 kg = 90 g
4.7 g = 4700 mg
0.75 kg = 750 g

26. Conversions between Units
What if we are converting up the scale, going from smaller  larger units?
Move the decimal point 3 places to the Left
200 mL = ___?___ L
mL to L is different of 1000 units
L  mL
Smaller  larger
0.2 L

27. Conversions between Units
50 mcg = ___?___ mg
mcg to mg is different of 1000 units
Kg  g  mg  mcg
Smaller  larger
0.05 mg

28. Small group Practice 4200 mL = ___?___ L 520 mg = ___?___ g
30 mcg = ___?___ mg
7420 g = ___?___kg
2.2 L = ___?___ mL

29. Small group Practice 4200 mL = 4.2 L 520 mg = 0.52 g 30 mcg = 0.03 mg
7420 g = 7.42 kg
2.2 L = 2200 mL