NCLEX tom- Titration question!!!!

MsNursingStudent · Jun 30, 2008

are you sure you have all parts to the question?

Kiringat · Jun 30, 2008

ok. i think i got it.

the formula is:

rate (ml/hr) [color=#330000]x concentration ("unit"/ml)

time (60 min/hr) [color=#330000]x weight in kilograms

so plugging in the info:

5 (ml/hr) x 320 mcg ("unit"/ml)

60 (60 min/hr) x 68 kg

that gets you 1600/4080 = 3.92

i think.....

BebobthefrogFNP · Jun 30, 2008

ok. i think i got it.
the formula is:
rate (ml/hr) [color=#330000]x concentration ("unit"/ml)
time (60 min/hr) [color=#330000]x weight in kilograms
so plugging in the info:
5 (ml/hr) x 320 mcg ("unit"/ml)
60 (60 min/hr) x 68 kg

that gets you 1600/4080 = 3.92
i think.....

that's what i got too but, i did dimensional analysis.

momathoner09, BSN, MSN, APRN · Jun 30, 2008

Thank you!!!! Hopefully I don't have too many of these crazy questions tom. My friend had 6 titration calculations on her NCLEX. I will fall out of my chair if that happens...literally

2008China · Jun 30, 2008

ok. i think i got it.
the formula is:
rate (ml/hr) [color=#330000]x concentration ("unit"/ml)
time (60 min/hr) [color=#330000]x weight in kilograms
so plugging in the info:
5 (ml/hr) x 320 mcg ("unit"/ml)
60 (60 min/hr) x 68 kg

that gets you 1600/4080 = 3.92
i think.....

should be： 5 (ml/hr) x 3200 mcg ("unit"/ml)

60 (60 min/hr) x 68 kg

then16000/4080 = 3.92

OrchidRN08 · Jun 30, 2008

why do you have to change your mg to mcg? is that part of the formula? i know she gave the answer as 3.92 mcg/kg/min but why can't it be mg/kg/min?????

Italia13 RN · Jun 30, 2008

yea i am confused too. If i would of got this question on boards I would of for sure got it wrong becasue I would of done mg/kg/min. How do you know from the question u have to convert to mcg?

suzanne4, RN · Jun 30, 2008

Best of luck on your exam. But you should have everything already put away and should not be reviewing ever the day before the exam.

Hands and Heart · Jun 30, 2008

The drug order for dopamine (and some other titrated drugs) is usually given as mcg/kg/min. You can also look at the units given in the answer choices to know what units in which you have to have your final answer.

nursemich · Jul 1, 2008

[color=#660000]titration: flow rate

$vspacer.gif$ $ivpole.jpg$ [color=#660000]calculating flow rate (ml /hr): key elements:

dosage must be given.
- this may be expressed as "amount"/kg/min, units/hr, mg/min, etc.
[*] time is constant (60 min/hr).
[*] weight of the client is expressed in kilograms.
[*] concentration of the infusion.
- when using a dosage of mcg/kg/min, the end concentration must be expressed in mcg/cc. (convert mg to mcg.).
- you will need to use r & p to find how many units of a medication in a ml. (see below.)
- [color=#330000]rule is: to calculate, one must have like amounts in dose and concentration.

formula to calculate flow rate:

dose ("unit"/kg/min) [color=#330000] x wt in kg [color=#330000]x 60 (min/hr)
concentration of infusion ("unit" / ml)

[color=#330000]example:

[color=#0080c0]for the client whose weight is 130 lbs and has dopamine ordered at 8 mcg/kg/min, what rate should the infusion pump be set for a solution of 400 mg dopamine in 250 ml d5w?

[color=#330000]critical information:

[color=#0080c0]client's weight: 130 lbs
[color=#0080c0]dosage: 8 mcg/kg/min
[color=#0080c0]solution: 400 (mg) in 250 (ml)

[color=#330000]tip: 1) convert wt to kg. 130 / 2.2 = 59.09 kg

2) find concentration of dopamine in 1 cc.

[color=#0080c0]400/250 = 1.6cc[color=#0080c0]

3) concentration is 1.6 mg /cc. convert the mg to micrograms.

[color=#0080c0]1.6 (mg) x 1000 (mcg per 1 mg) = 1600 mcg/cc.

[color=#0080c0]now that you have gathered all the information, plug it into the formula:

8 ("unit"/kg/min) [color=#330000] x 59.09 (wt in kg) [color=#330000]x 60 (min/hr

)

1600 ("unit" / ml)

=

28363.32

1600

x

=

17.727

[color=#ffffff]17.727 or 18 ( ml/hr) will dialed on the pump.

nursingpower · Apr 29, 2009

why do you have to change your mg to mcg? is that part of the formula? i know she gave the answer as 3.92 mcg/kg/min but why can't it be mg/kg/min?????

i know i am very late but to make sense to people who may come upon this question and still want an answer, i hope this helps.

in a critical care setting (icu, er, sdu) there are potent drugs that need to watch closely by rn's. it is a matter of life or death. if we give to little or too much, the room for error is small. the patients body weight is critical because that makes the difference from patient to patient. micrograms is used according to the manufactuers instructions.

vasoactive drugs by definition are drugs that elicit vasoconstrictive or vasodilative action on blood vessels. if you look in your drug books (i have mosby's ndr) you will notice under the dosage/route/iv section that the instructions for iv route is to give in mcg/kg/min or mcg/min. if you notice in the pharmacokinetics section many of these drugs (iv form) have a very fast onset and short duration and half-life. these are some drugs that are titrated in critical care settings and their onset, duration and half-life straight from the nursing drug reference. (all of these drugs are ordered in mcg/min or mcg/kg/min according to the drug reference.)

nitroprusside o: 1-2min d: 1-10 min h: 2min

dopamine o: 5 min d:

dobutamine o: 1-2 min d: peak 10 min h:2 min

nitroglycerin o: 1-2min d: 3-5min h: 1-4min

in my opinion it would make sense to order these small doses (mcg) per minute because the effects last a few minutes and hemodynamics could change a little or alot from min to min. we have to do all the calculations just to put them on pumps. i am just glad we don't have to titrate manually..lol. what did they do before pumps?