Can someone help me figure this out?

hypocaffeinemia, BSN, RN · Jan 9, 2009

Order: Mezlin 450mg IVPB every 4 hours.
Supply: Mezlin 1 gram vial.
Label directions: Reconstitute each 1 gram with 10ml of sterile water and further dilute in 50ml NS to infuse over 30 minutes. (100mg/1ml).

1.) How many mL's will you draw from the vial after reconstitution?

4.5 mL. If it's 100mg per mL and you need 450 mg, you'd draw up 4.5 mL

2.) Calculate mL/hr to set the IV pump.

You had a total of 54.5 mL (4.5 mL + 50 mL bag) to infuse. You need to give it over 30 minutes. I could break this down dimensional analysis style, but the easy way to rate something for 30 minutes is to set the per hour to double the amount you need to infuse. In this case, that'd end up being 109 mL /hour.

Basically, 54.5 mL / 0.5 hours = 109 mL/hours

The reason they give you 100 mL / hour as the correct answer is because they were lazy and forgot to add the extra 4.5 mL to the total volume.

3.) Calculate the drops per minute with a drop factor of 15 gtts/ml.

109 mL per hour * (15 gtt / 1 mL) * (1 hour / 60 mins) = 27.25 rounded to 27 gtt / min.

Of course, you'd get 25 gtt / min if you substitute 100 for 109.

Answers: 4.5mL; 100ml/hr; 25 gtts/min.

butrfli · Jan 9, 2009

Ahhhhhhh, no wonder why I couldn't figure this out. It helps to have the correct answers! :banghead:

Thank you, thank you, thank you!

Daytonite, BSN, RN · Jan 9, 2009

order: mezlin 450mg ivpb every 4 hours.

supply: mezlin 1 gram vial.

label directions: reconstitute each 1 gram with 10ml of sterile water and further dilute in 50ml ns to infuse over 30 minutes. (100mg/1ml).

1.) how many ml's will you draw from the vial after reconstitution?

dose desired:

450 mg

dose on hand:

1 gram

amount the dose on hand comes in:

10 ml

conversion factor:

1 gram = 1000 mg

450 mg

(dose desired)

/1 gram

(dose on hand)

x 10 ml

(amount the dose on hand comes in)

/1 x 1 gram/1000 mg

(conversion factor)

=

4.5 ml

(amount to give)

2.) calculate ml/hr to set the iv pump.

amount to give:

50 ml of ns (they are not including the mezlin as part of the calculations)

time to give:

30 minutes

conversion factor:

60 minutes = 1 hour

note:

all iv pumps are set at

mls per hour

.

50 ml

(amount to give)

/30 minutes x 60 minutes/1 hour

(conversion factor)

=

100 ml/hour

(rate of pump)

3.) calculate the drops per minute with a drop factor of 15 gtts/ml.

100 ml/1 hour

(infusion rate)

x 15 gtts/ ml

(drop factor of iv tubing)

x 1 hour/60 minutes

(conversion factor)

=

25 gtts/minute

(drip rate)

butrfli · Jan 9, 2009

order: mezlin 450mg ivpb every 4 hours.
supply: mezlin 1 gram vial.
label directions: reconstitute each 1 gram with 10ml of sterile water and further dilute in 50ml ns to infuse over 30 minutes. (100mg/1ml).
1.) how many ml's will you draw from the vial after reconstitution?
dose desired:
450 mg
dose on hand:
1 gram
amount the dose on hand comes in:
10 ml
conversion factor:
1 gram = 1000 mg
450 mg
(dose desired)
/1 gram
(dose on hand)
x 10 ml
(amount the dose on hand comes in)
/1 x 1 gram/1000 mg
(conversion factor)
=
4.5 ml
(amount to give)
2.) calculate ml/hr to set the iv pump.
amount to give:
50 ml of ns (they are not including the mezlin as part of the calculations)
time to give:
30 minutes
conversion factor:
60 minutes = 1 hour
note:
all iv pumps are set at
mls per hour
.
50 ml
(amount to give)
/30 minutes x 60 minutes/1 hour
(conversion factor)
=
100 ml/hour
(rate of pump)
3.) calculate the drops per minute with a drop factor of 15 gtts/ml.
100 ml/1 hour
(infusion rate)
x 15 gtts/ ml
(drop factor of iv tubing)
x 1 hour/60 minutes
(conversion factor)
=
25 gtts/minute
(drip rate)

thanks also to daytonite!

so, seeing the way this question is stated, how would you have normally answered this, with the mezlin included or not? this can obviously be two answers depending on how someone is thinking and it doesn't seem to be a fair, clearly stated question. if this was a test question, a lot of people could get this wrong, errrrrrrrrr, and every point counts! this is what aggravates me the most!

i would think that we would normally calculate the ml's of the drug along with the 50 ml of ns to get a more accurate infustion rate, (even though there's not much rate difference in this calculation) right?

:confused:

Daytonite, BSN, RN · Jan 10, 2009

Thanks also to Daytonite!
So, seeing the way this question is stated, how would you have normally answered this, with the Mezlin included or not? This can obviously be two answers depending on how someone is thinking and it doesn't seem to be a fair, clearly stated question. If this was a test question, a lot of people could get this wrong, errrrrrrrrr, and every point counts! This is what aggravates me the most!
I would think that we would normally calculate the ml's of the drug along with the 50 ml of NS to get a more accurate infustion rate, (even though there's not much rate difference in this calculation) right?

At work I would have included the 4.5 mL with the 50 mL to come up with 109 mL/hour and 27 gtts/minute. All I can suggest is that you ask your instructors what they want you to answer to these problems, or else give both answers on the test.