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Physician orders for a 32 week patient with preterm labor, include Magnesium sulfate 40 grams in 100 ml D5 1/4NS. Loading dose of 4 grams over 30 minutes, then maintain magnesium sulfate at 2 grams per hour.
Set up the the IV Pump for the loading dose
Set up the IV Pump for the maintenance dose.
First is the total IVF really only 100cc's for this is typically mixed in 1000cc of fluid. If it is really only 100cc of IVF then the calculation would be as follows. This problem has several steps. Med Math Examples
Every dosage problem has essential steps.....First KNOW your conversions..........Then answer for every problem
Volume on hand
Any conversions: Lbs/Kg, grams/mg, mg/mcg
administration set up:
1) If you have 40 grams in 100cc's....how many mg's is there in 100cc's.....you multiply 40grams by 1000......there is 40000mgs/100cc right?
2) If you have 40000mgs/100cc how many mg do you have per cc? There is 400mg/cc right? 40000/100 (40000 divived by 100)
3) How many cc's are needed to be given to total 4000mgs? )4000/400 =) 10cc equals 4000mgs.
4) What does the pump need to be set at to deliver 10cc over 30 min?
If however the 40grams of MgSO4 in 1000cc the calculations would be completely different......
1) Then there would be 40gms in 1000cc of fluid....which means there is 40000mg in 1000cc's. How many mg's is there per cc? 40000/1000 =
2) It is then 40mgs/cc. If you have 40mgs/cc how many cc's will it take to give you 4000mg?
3) You need 100cc of fluid to infuse over 30 min.....what would your pump setting be to infuse 100cc's over 30 min? 100cc/30min x 60gtt factor=200cc/hr for 30 min.
4) Now you need 2gm/hr or 2000mg/hr...every hour. How many cc's of fluid do you need to contain 2000mgs.
5) If 50cc of fluid contains 2000mgs on MgOS4...how fast do you need to set the pump to deliver the 50cc in 1 hour? 50cc/60min x 60= 50cc/hr.