1. Medical Math & Terminology HEALTH SCIENCE II

2. Introduction Working in health care requires the use of math skills to measure & perform various types of calculations. Common uses include: ◦Calculating medication dosages ◦Taking height & weight readings ◦Measuring intake & output (I&O) ◦Billing & bookkeeping ◦Performing laboratory tests (WNL)

3. Errors in math can have serious negative effects on patients Example: Administering the wrong dosage of a medication can kill a patient Remember: THE DOSE MAKES THE POISON!!

4. Basic Calculations To work safely in healthcare, it is essential to be able to add, subtract, multiply & divide whole numbers, decimals, fractions & percentages

5. Basic Calculations Addition & subtraction of whole numbers may be used in: ◦Counting or totaling supplies ◦Determining weight loss or gain ◦Measureing I & Os Multiplication & Division may be used in: ◦Performing laboratory tests (O2 saturation, Caridac output) ◦Calculating budgets & salaries ◦Compiling statistics on disease & death rates

6. Basic Calculations Decimals: ◦A way of expressing parts of numbers or anything else that has been divided into parts ◦Parts expressed in units of 10 Examples: ◦Determining medication doses ◦Measuring respiratory function ◦Billing charges on patient accounts

7. Basic Calculations Fractions: ◦A way of expressing numbers that represent parts of a whole Examples: ◦Measuring solutions for lab tests (Normal Saline) ◦Calculating height & weight ◦Mixing solutions, such as disinfectants, for infection control

8. Basic Calculations Percentages: ◦Used to express wither a whole or part of a whole ◦The whole is expressed as 100% Examples: ◦Recording statistics, i.e. number of people who die from lung cancer ◦Calculating the amount of taxes that must be subtracted from a salary check ◦Determining dietary requirements or calculating special (therapeutic) diets

9. Basic Calculations Ratios: ◦Show relationships between numbers or like values, how many of one number or value is present compared to another Examples: ◦Express the amount of each medication in a combination med (Percocet 5-325) 5mg of acetaminophen & 325 mg of oxycodone ◦Express the strength of a solution (also frequently expressed as a %)

10. Basic Calculations Rounding Numbers: ◦Changing to the nearest 10, 100, or 1000 etc. ◦The degree of accuracy required & the size of the number determines which number to round Example: ◦350.4mg of milk of magnesia based on a patient’s weight given as 350mg

11. Basic Calculations Proportions: ◦A statement of equality between 2 ratios ◦Used in solving many math problems in healthcare Examples: ◦Calculating height to feet & inches ◦Calculating weight to pounds & ounces ◦Determining the proper dosage of medication

12. Basic Calculations Estimating: ◦Anticipating the results or outcome of a calculation ◦Calculating an approximate answer & judging if the calculated results seem reasonable

13. Precautions of Calculations When calculations are performed without thought & answers are simply accepted, errors can go unnoticed (Which can be deadly) Knowing when an answer “just doesn’t look right” serves as an alert to double-check the results

14. Precautions with Calculations Do NOT work on “auto-pilot” when using math in the workplace

15. Roman Numerals Used occasionally for some medications, solutions & ordering systems Also used for filing or materials organization

16. Roman Numerals All numbers can be expressed by seven key numerals: I-1C- 100 V-5D- 500 X-10M- 1000 L- 50

17. Roman Numerals If a smaller number is placed in front of a larger one, the smaller number is subtracted from the larger Example: ◦IV= 4, the “1” is placed before the “5” so it is subtracted (5-1)

18. Roman Numerals If a smaller numeral is placed after the larger numeral, the smaller is added to the larger Example: ◦VI= 6, the “1” is after the “5” so it is added (5+1)

19. Roman Numerals When the same numeral is placed next to itself, it is added Example: ◦III- 1+1+1= 3 ◦XX- 10+10= 20 ◦IXX- Two of the same numerals preceded by a smaller numeral, the same rules apply 10+10-1= 19 or 10-1+10=19

20. Roman Numerals The same numeral is not placed next to itself more than 3 times Example: ◦XXX= 30 ◦But……. XL= 40 (NOT XXXX)

21. Systems of Measurement Metric: ◦More accurate than the Household System ◦Conversion is easier because it is based on units of ten

22. Systems of Measurement Household: ◦Method of measurement most familiar to students educated in the US ◦Various units of measurement relate to each other & can be converted among themselves

23. Systems of Measurement Apothecary: ◦Oldest & least used of measurement systems ◦Some physicians still write orders using this system

24. Temperature Conversion Fahrenheit & Celsius: ◦To convert between the two units of measure, use the following formulas: ◦C to F(C x 1.8) +32=F ◦F to C(F-32) / 1.8= C

25. Military Time Military time (aka 24- hour clock) is frequently used in health care to avoid confusion created by AM & PM used in the traditional system of time. In traditional time, the omission of AM or PM can make an error of 12 hours time!

26. Military Time When using Military Time, remember the following ◦Time is always expressed using four digits (e.i. 0030, 0200, 1200, 1700) ◦AM hours are expressed with the same numbers as the traditional clock (i.e. 1 AM = 0100) ◦An easy way to convert the PM hours is to add the time to 1200 (i.e. 1 PM = 1200 + 0100 = 1300) ◦When time is verbalized, there is a specific way that it is expressed (1300 = thirteen hundred hours, 0100= Oh One Hundred hours)