Note: This is the second half in the process required to prepare doses. This work sheet should be linked with the previous lecture entitled Morning Elution.

Refer to the completed Daily Radiopharmaceutical Log by linking to it and then printing it. Then as you read this lecture, follow the completed log. FYI - Check all calculations to assure that you understanding this process!

1. In the beginning of the sheet there are three blanks (underlined area below) that must be filled-in in order to identify the kit being prepared
1. Radionuclide: Tc99m
2. Physical Form: Liquid
3. Chemical Form: Tc99mMDP
2. Under Preparation time and date fill-in the blanks
1. Time: 900
2. Date: Today's date
3. Under Total Activity in mCi/mL, fill-in the bank
1. 250/5
2. You have extracted 250 mCi of Tc99m out of the elution vial
3. The dose needs to be expanded with saline
4. In this case I have decided to add 2.2 mL so that there is a total of 5.0 mL of Tc99mMDP in solution
5. More on kit expansion, but first let us finish completing the blanks
4. Expiration Date and Time
1. In order to fill this out you need to refer to the package insert and look up this value. A package insert comes with every radiopharmaceutical kit and it is regulated by the FDA
2. Hypothetically we will say that the expiration time is 6 hours later (most, but not all kits have this value)
3. Time: 1500 (when the kit expires)
4. Date: Today's Date
5. Finally you must discard the vial into the hot trash once you have completed all your doses for the day
1. Put in Decay Bin: Next Day
2. This is usually done the next day - it will reduce your radiation exposure
6. More on kit expansion - known as the minimum/maximum volume and minimum/maximum activity
1. Located in the package insert are the values for min/max volume and activity levels
2. You must stay within these values whenever you prepare a kit
3. Hypothetically I have defined that many kits have the following min/max values (but not all)
1. Volume: 2 - 8 mL
2. Activity: 50 - 300 mCi
4. Notice that the volume I selected was about in the middle of the min/max range. This is done out of habit, but also it's good not to "push" the limits of the kit
7. Now we are ready to start entering the data into the cells below
8. At the first data entry you should start off by identifying the amount total activity and volume in solution (remember we did the same thing with Morning Elution)
1. Under Time fill in the word "At"
2. Under name enter "900 hours"
3. Under Type of Study enter "Prepared Tc99mMDP"
4. For mCi/mL enter "50.0"
5. Total mL or "T. mL" enter "5.0"
6. For mCi/Dose enter "250"
7. Remaining volume or "R. Vol." enter "5.0"
8. These values are identified below in their appropriate cells

Time	Name	Type of Study	mCi/mL	T. mL	mCi/Dose	R. Vol. (mL)
At	900 hours	Prepared Tc99mMDP	50.0	5.0	250	5.0

9. You are now ready to start entering your patient doses
10. Based on the previous elution information you will prepare the following doses of Tc99mMDP given the following times: 900, 1000, 1200, 1300, 1400, and 1500. Oh we had an add-on pediatric dose to 1430 hours (more on that when we get to it)
11. Calculation for the 900 hours dose
1. Time - "900"
2. Name - "Adult 1" (patient's name)
3. Type of Study - "Whole Body Bone Scan"
4. mCi/mL - "50.0" (nothing to decay, yet)
5. T. mL enter 0.5 (25mC/50mCi/mL)
6. mCi/Dose - "25" (the amount for the adult dose)
7. R. Vol. - "4.5" (5.0mL - 0.5mL = 4.5 mL)
8. These values are identified below in the appropriate cells

Time	Name	Type of Study	mCi/mL	T. mL	mCi/Dose	R. Vol. (mL)
900	Adult 1	Whole Body Bone Scan	50.0	0.5	25	4.5

12. Calculation for the 1000 hours dose (Adult 2)
1. Time - "1000"
2. Name - "Adult 2"
3. Type of Study - "Whole Body Bone Scan"
4. mCi/mL - "44.6" (0.891 x 50mCi)

The above value is arrived at by taking the previous mCi/mL and multiplying it by the decay factor: 50 mCi/mL * 0.891 (df) = 44.6 mCi/mL

5. Under mCi/Dose - "25"
6. Under R. Vol. - "3.9" (4.5 mL - 0.6 mL = 3.9 mL)
7. These values are identified below in the appropriate cells

Time	Name	Type of Study	mCi/mL	T. mL	mCi/Dose	R. Vol. (mL)
1000	Adult 2	Whole Body Bone Scan	44.6	0.6	25	3.9

13. Continue add the appropriate data for Adult 3, Adult 4, Adult 5, and Adult 6 applying then same technique
14. The correct entries are noted below (FYI - don't forget to decay your mCi/mL)

Time	Name	Type of Study	mCi/mL	T. mL	mCi/Dose	R. Vol. (mL)
1100	Adult 3	Three Phase Bone Scan	39.7	0.6	25.0	3.3
1200	Adult 4	Whole Body Bone Scan	35.4	0.7	25.0	2.6
1300	Adult 5	Three Phase Bone Scan	31.5	0.8	25.0	1.6
1400	Adult 6	Three Phase Bone Scan	28.0	0.9	25.0	0.7

15. Notice that the last patient was an add-on and it's a pediatric dose!
16. How is a pediatric dose calculated?
1. Assume the patient weight is 45 lb.
2. This needs to be converted to kg - 45/2.2 = 20.5 kg
3. Now determine the ratio of the pediatric dose to standard man - 20.5/70 = 0.3
4. Then take the adult dose and multiply by the above ratio - 25.0 mCi x 0.3 = 7.3 mCi
5. For any pediatric dose follow these steps



6. The correct entries are identified below

Time	Name	Type of Study	mCi/mL	T. mL	mCi/Dose	R. Vol. (mL)
1430	Pediatric Pt	Three Phase Bone Scan	26.4	0.3	7.3	0.4

17. You can apply this concept to the other two radiopharmaceuticals you prepared - I am available if you should have any questions
18. This will be covered in class
19. You will be given homework to further sharpen your dose calculating skill

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