Please help with this math!!

[Starfish1]

can someone please help me and explain why one answer is in mg/min vs mg/hr?!?!? my teacher cannot answer my question yet i think this is a valid question- i personally would answer mg/hr for both but they each have different answers....

your patient admitted with an exacerbation of asthma has an aminophylline (theophylline) drip running at 6 ml/hr. the bag that is up is 500ml d5w with 2 grams of aminophylline. how much is the patient receiving? answer is 24 mg/hr

your patient has an aminophylline drip of 500mg aminophylline in 250ml ns. how much if the patient receiving if his pump is running at 12ml/hr? answer teacher gave is 0.4 mg/min i would have answered this question as 24mg/hr

your patient in hypertensive crisis has been ordered to have nipride (nitroprusside) infusion. the 190 pound patient has a 500ml bag of ns with 100mg of nipride hanging with the pump running at 8ml/hr. what is the dosage that the patient is receiving? my answer is .031mcg/kg/min teachers answer is .026 mg/min again i think my answer is correct...please help me understand why it isn't

your 220 pound patient has a dopamine drip running at 25 ml /hour. the bag that is hanging is 500 ml d5w with 900mg of dopamine. how much is the patient receiving? my answer is 7.5mcg/kg/min which is correct

[kgh31386, BSN, MSN, RN]

That's a little strange. Usually when you have any math question, they tell you what units they're looking for. It doesn't make sense that your teacher isn't giving a rationale of why you aren't right.

[awalker1015]

I think it is odd, too, that you have a dosage in mg/min when you have an infusion pump ( I am specifically referring to the second problem). I thought universally all pumps were calculated for ml/hr?!?

[chare]

the information that you have been provided does not meet the requirements of the 6 rights of medication administration; medication, dose/dosing, route, time/timing, reason, and documentation. remember, in practice if you ever receive a medication order missing any of these components you need to contact the ordering provider for clarification prior to administering the first dose.

all of the answers that you have provided are correct; however you weren't provided the dosing format that the instructor wanted. if the questions are multiple choice, select the answer that fits the format provided. if not, prior to working any of the problems as the instructor how he/she would like the dosing to be expressed.

i think it is odd, too, that you have a dosage in mg/min when you have an infusion pump ( i am specifically referring to the second problem). i thought universally all pumps were calculated for ml/hr?!?

many newer infusion devices allow you to program the medication concentration and patient weight, enter the dose you want administered and the device will calculate the rate.

i hope this information was helpful.

[vanlo001]

starfish1: these questions are very typical of real life applications you will find in the healthcare setting. it is true that a lot of the newer pumps will calculate an infusion rate based on the dose entered but you must be able to do the math to figure the probelm out. a life threatening an devestating error or near miss could occur if you don't understand these concepts and almost every hospital requires a medication calculation test upon hiring. that being said i'll walk you through the two problems.

your patient has an aminophylline drip of 500mg aminophylline in 250ml ns. how much if the patient receiving if his pump is running at 12ml/hr? answer teacher gave is 0.4 mg/min i would have answered this question as 24mg/hr 0.4mg/minute and 24mg/hr are the same answer. however many medications are reported in a specific way depending on the dose and concentration. (the reason they are the same is that 24mg/hr divided by 60 minutes in an hour = 0.4mg/minute. aminophyline may be that type of drug. it could be because this is a dose for a pediatric patient? the dilution is the key that perhaps this is a smaller patient.

your patient in hypertensive crisis has been ordered to have nipride (nitroprusside) infusion. the 190 pound patient has a 500ml bag of ns with 100mg of nipride hanging with the pump running at 8ml/hr. what is the dosage that the patient is receiving? my answer is .031mcg/kg/min teachers answer is .026 mg/min again i think my answer is correct...please help me understand why it isn't i got the same answer as your instructor. i first find the kg by dividing 190 by 2.2 and get 86.363. 100mg divided by 500ml tells you that there is .2mg/ml multiply .2mg by 1000 to get the mcg= 200mcg/ml. after converting to these units of measure you can find the answer : the infusion is running at 8ml/hr. take 8ml x the 200mcg/ml= 1600mcg/hr divide 1600mcg by the weigh to find out how many mcg/kg. divide 1600 by 86.363 = 18.526mcg/kg/hr divide by 60 minutes to find out the amount of mcg per kg per minute. 18.526 divided by 60 equals 0.3087 or 0.31mcg/kg/min.

most days you will not have calculations this complex and there are various tools to help you work through these problems. however, they are important. also when doing these multiple steps usually you are doing it with a second nurse. however it is imperative that you grasp these concepts. you will get it just make sure to double check your work and take your time to go through each step. kudos to you for asking for help.

[vanlo001]

Sorry on closer inspection starfish1 I got the same answer you got for the second question. I'm not sure how your instructor came up with that answer.

[Starfish1]

thanks I just feel sooo lost the teacher got frustrated and said these were the correct answers and just stopped answering questions....I know I am right...this test is for pts this semester and I dont know what to do....

[morte, LPN, LVN]

the 3+4 are properly answered by instructor.....the other info that you are providing is extraneous.

the 2' one i havent a clue why she thinks you should have answered in mg/min instead of mg/hr.....good luck