Cert Exam 5e Chapter 5

[Audio] Welcome to the Certification Exam Review Fifth Edition presentation for chapter five..

[Audio] Chapter 5: Pharmacy Conversions and Calculations.

[Audio] At the end of this chapter, you will be able to: Convert temperatures between the Fahrenheit and Celsius systems. Convert standard time into military time. Convert common systems of measurement into the metric system. Understand the concepts for solving problems using ratio-proportion techniques..

[Audio] Section five point one: Reviewing Conversion Formulas and Measurements.

[Audio] When converting temperatures between Celsius and Fahrenheit, you have to apply formulaic equations. Technicians are often asked to monitor refrigerator and freezer temperatures to ensure that pharmaceuticals are properly stored. Memorizing these equations will help you to do quick conversions..

[Audio] While the 12-hour clock works for most everyday activities, it has become common internationally in health care to use the 24-hour clock, also called military time. The military system counts from midnight continuously until to start again at 0000. The designations a.m. and p.m. do not exist in military time. Instead, hours escalate from midnight or 0000 to noon or 1200 up to 2359, the time just before midnight..

[Audio] In health care today, most products are dosed in metric units, such as milligrams or milliliters. However, with very few exceptions, non-metric measure systems are not used in general pharmacy practice today and can lead to medication errors if put into practice. The only apothecary unit still sometimes used in prescription stock labels is the grain, a dry weight measure. However, using the grain can be problematic: 1 grain can be equal to 60 milligrams, as in thyroid, and also equal to 64.8 milligrams, as in phenobarbital. Because of the lack of standardized conversion, the grain is not a safe measurement to use and is being phased out..

[Audio] The metric system is based on multiples of 10. The advantages of the metric system include the following: · consistent measurement values across the world and fields of use, especially science · consistent decimal notation in which units are based on multiples of 10 · consistent escalation and de-escalation in value for ease of memory and use · same correlations of value proportion in units of measurement across the dimensions of length, volume, and weight. The metric system of measurements is considered universal, so it is necessary to memorize the units of measurement in Table 5.5..

[Audio] The metric system is based on multiples of 10. The advantages of the metric system include the following: · consistent measurement values across the world and fields of use, especially Science, consistent decimal notation in which units are based on multiples of 10, consistent escalation and de-escalation in value for ease of memory and use , same correlations of value proportion in units of measurement across the dimensions of length, volume, and weight..

[Audio] The metric system of measurements is considered universal, so it is necessary to memorize the units of measurement for speedy conversions as a general rule of practice..

[Audio] Prefixes, or syllables placed at the beginnings of words, are added to the names of the basic metric units to specify a particular size of unit measure, such that milli-, which means one one thousandth can be added to liter to form a new unit milliliter, or one-thousandth of a liter. The set of standardized metric prefixes based on powers of 10 is called the Systeme International..

[Audio] The most common calculations in pharmacy involve conversions up to higher metric proportional amounts and down to lower amounts using milligrams, grams, and kilograms, or milliliters and liters. Multiplying or dividing by 1,000 moves up and down the unit steps. In proper calculations, the decimal point will move to the left when converting to larger units, and to the right when converting to smaller units..

[Audio] Perhaps no mathematical technique is used more frequently in pharmacy practice than that of ratios and proportions. Ratios and proportion equations are used in converting measurement units, determining dosages, and in compounding formulas. Two ratios that have the same value when simplified are different ways of saying the same ratio, such as 1 to 2 and 4 to 8. They are called equivalent ratios. A pair of equivalent ratios together is called a proportion. The first and fourth numbers, or outside numbers, are called the extremes, and the second and third numbers, or inside numbers, are called the means..

[Audio] Pairs of equivalent ratios are used often in pharmacy to make conversions from one measurement system to another. In these problems, it is common to express the unknown quantities by using letters from the end of the alphabet to represent them, especially x, y, and z. The steps for solving for the unknown number in the ratio-proportion method are: Step 1 Create the proportion by placing the ratios in fraction form. Step 2 Check that the unit of measurement in the numerators is the same and the unit of measurement in the denominators is the same. Step 3 Solve for y by multiplying both sides of the proportion by the denominator of the ratio containing the unknown, and cancel. Step 4 Check your answer by determining if the product of the means equals the Pharm product of the extremes..

[Audio] This concludes the Certification Exam Review Fifth Edition presentation for chapter five..