Re: PTCB Practice Test/ anyone have time to discuss math from this test?

[Guest guest]

is there anyone who has any time left and did really good in these

math problems, who wouldnt mind answering or explaining a few of

them to a " mathematically-challeged-me " !

i did pretty good in a lot of them, but there were a few that

stumped me completely, my times running out... help?

thanks,

Jo

>

> Hi Everyone,

>

> I found a Practice Test at the site below:

>

> Test: http://www.io.com/~fantasy/ptcb.html

> Answers: http://www.io.com/~fantasy/ptcb-answers.html

>

> Good luck!

>

> --

> Your servant in Christ,

>

> Jay N. Forrest

> http://www.JayForrest.net

>

[Guest guest]

which ones italypharmtechie

italypharmtechie <jocelynrhodes@...> wrote:is there anyone who has any

time left and did really good in these

math problems, who wouldnt mind answering or explaining a few of

them to a " mathematically-challeged-me " !

i did pretty good in a lot of them, but there were a few that

stumped me completely, my times running out... help?

thanks,

Jo

>

> Hi Everyone,

>

> I found a Practice Test at the site below:

>

> Test: http://www.io.com/~fantasy/ptcb.html

> Answers: http://www.io.com/~fantasy/ptcb-answers.html

>

> Good luck!

>

> --

> Your servant in Christ,

>

> Jay N. Forrest

> http://www.JayForrest.net

>

[Guest guest]

thanks stephanie, here they are. i just need to see them worked out,

i learn/understand better " visually "

#39 -- IV infusion order is received for aminophylline 500mg in

500ml of D5W to be infused at 1mg/kg/hr. pt. weighs 154lb. what is

flow rate in ml/min?

#48 -- IV infusion order received for lidocaine 2g in 250ml of D5W

to be infused at 3mg/min. flow rate in ml/hr?

> >

> > Hi Everyone,

> >

> > I found a Practice Test at the site below:

> >

> > Test: http://www.io.com/~fantasy/ptcb.html

> > Answers: http://www.io.com/~fantasy/ptcb-answers.html

> >

> > Good luck!

> >

> > --

> > Your servant in Christ,

> >

> > Jay N. Forrest

> > http://www.JayForrest.net

> >

>

>

>

>

>

>

>

[Guest guest]

Here is two different ways for each problem. Using dimensional analysis start

with what they ask for which is ml/min. Cancel out the terms and you are left

with ml/min

Problem number one:

154 /2.2 = 70 kg

70 kg x 1 mg/kg/hr = 70 mg/hr

500ml x 70 mg x 1 hr

500 mg 1 hr 60 min = 1.17 ml/min OR

since we figured the patient gets 70 mg/hr (60 min)

500 mg = 70 mg

500 ml X

X = 70 ml/hr divided by 60 to get 1.17 ml/min

Problem number two:

they want ml/hr. so start out with ml

250 ml x 3 mg x 60 min = 22.5 ml/hr OR

2000 mg (2g) 1min 1 hr

3mg/min X 60 min = 180mg/ hour

2000 mg (2g) = 180 mg

250 ml X

X = 22.5 ml

I hope that helps

italypharmtechie <jocelynrhodes@...> wrote:

thanks stephanie, here they are. i just need to see them worked out,

i learn/understand better " visually "

#39 -- IV infusion order is received for aminophylline 500mg in

500ml of D5W to be infused at 1mg/kg/hr. pt. weighs 154lb. what is

flow rate in ml/min?

#48 -- IV infusion order received for lidocaine 2g in 250ml of D5W

to be infused at 3mg/min. flow rate in ml/hr?

> >

> > Hi Everyone,

> >

> > I found a Practice Test at the site below:

> >

> > Test: http://www.io.com/~fantasy/ptcb.html

> > Answers: http://www.io.com/~fantasy/ptcb-answers.html

> >

> > Good luck!

> >

> > --

> > Your servant in Christ,

> >

> > Jay N. Forrest

> > http://www.JayForrest.net

> >

>

>

>

>

>

>

>

[Guest guest]

I am resending, my underlined portions are not showing up which makes the

problem look kinda crazy

Problem number one:

154 /2.2 = 70 kg

70 kg x 1 mg/kg/hr = 70 mg/hr

500ml / 500mg x 70 mg/ 1 hr x 1 hr/60 min = 1.17 ml/ min

OR

since we figured the patient gets 70 mg/hr (60 min)

500 mg / 500 ml = 70 mg/ X

X = 70 ml/hr divided by 60 to get 1.17 ml/min

Problem number two:

they want ml/hr. so start out with ml

250 ml /2000mg (2g) x 3 mg/1min x 60 min/1hr = 22.5 ml/hr

OR

3mg/min X 60 min = 180mg/ hour

2000 mg (2g) / 250 ml = 180 mg/ X

X = 22.5 ml

I hope that helps

stephanie garthrite <ladyofintellect1969@...> wrote: Here is two different

ways for each problem. Using dimensional analysis start with what they ask for

which is ml/min. Cancel out the terms and you are left with ml/min

Problem number one:

154 /2.2 = 70 kg

70 kg x 1 mg/kg/hr = 70 mg/hr

500ml x 70 mg x 1 hr

500 mg 1 hr 60 min = 1.17 ml/min OR

since we figured the patient gets 70 mg/hr (60 min)

500 mg = 70 mg

500 ml X

X = 70 ml/hr divided by 60 to get 1.17 ml/min

Problem number two:

they want ml/hr. so start out with ml

250 ml x 3 mg x 60 min = 22.5 ml/hr OR

2000 mg (2g) 1min 1 hr

3mg/min X 60 min = 180mg/ hour

2000 mg (2g) = 180 mg

250 ml X

X = 22.5 ml

I hope that helps

italypharmtechie <jocelynrhodes@...> wrote:

thanks stephanie, here they are. i just need to see them worked out,

i learn/understand better " visually "

#39 -- IV infusion order is received for aminophylline 500mg in

500ml of D5W to be infused at 1mg/kg/hr. pt. weighs 154lb. what is

flow rate in ml/min?

#48 -- IV infusion order received for lidocaine 2g in 250ml of D5W

to be infused at 3mg/min. flow rate in ml/hr?

> >

> > Hi Everyone,

> >

> > I found a Practice Test at the site below:

> >

> > Test: http://www.io.com/~fantasy/ptcb.html

> > Answers: http://www.io.com/~fantasy/ptcb-answers.html

> >

> > Good luck!

> >

> > --

> > Your servant in Christ,

> >

> > Jay N. Forrest

> > http://www.JayForrest.net

> >

>

>

>

>

>

>

>

[Guest guest]

Thank you for your display of help and dimensional analysis.

I will post another method as well.

Jeanetta Mastron CPhT BS

Founder/Owner

> > >

> > > Hi Everyone,

> > >

> > > I found a Practice Test at the site below:

> > >

> > > Test: http://www.io.com/~fantasy/ptcb.html

> > > Answers: http://www.io.com/~fantasy/ptcb-answers.html

> > >

> > > Good luck!

> > >

> > > --

> > > Your servant in Christ,

> > >

> > > Jay N. Forrest

> > > http://www.JayForrest.net

> > >

> >

> >

> >

> >

> >

> >

> >

[Guest guest]

Dear Jocelyn,

I usually teach this with dimensional analysis, as has shown

you, however I also teach what is called conceptual math. So here is

another way of `looking at' or approaching the math problem:

#39 -- IV infusion order is received for aminophylline 500mg in

500ml of D5W to be infused at 1mg/kg/hr. pt. weighs 154lb. what is

flow rate in ml/min?

First change the pts wt to kg since the drug is ordered in 1mg/kg/hr .

2.2 lb....154lb

------ = ------

1 Kg......X Kg

Cross Multiply:

1 x 154

-------- = X Kg = 70 Kg

2.2

1 mg/Kg

1 mg.....X mg

----- = ------

1 Kg.....70 Kg

Cross Multiply:

1 x 70

------ = X mg = 70 mg

1

Therefore it is 70mg/hr

This would be

70 mg /1hr X 1hr/60 min = 70 mg/60 min or 1.17 mg/1min

But there are 500mg/500ml. When `reduced to lowest terms' means

1 mg = 1ml,

1mg......1.17 mg

---- = -------

1 ml......X ml

Therefore 1.17 mg = 1.17 ml. Therefore by substitution:

1.17 mg/min is the same as 1.17 ml/min.

#48 -- IV infusion order received for lidocaine 2g in 250ml of D5W

to be infused at 3mg/min. flow rate in ml/hr?

2 grams = 2000 mg

Therefore

2000 mg/250ml

Now move/change this ratio upside down so that the ml are on the top

and the mg are on the bottom because they want ml/hr and we can go

from there once the ml are on the top:

250ml

-----

2000mg

Okay now multiply by the rate of 3mg/min

250ml.......3 mg

------- X -------

2000mg......1 min

Cancel out the mg's leaving ml/min

750 ml

--------

2000 min

Now change minutes to hours

750 ml......60 min

-------- x ------- = 22.5 ml/hr

2000 min.....1 hr

>

> thanks stephanie, here they are. i just need to see them worked out,

> i learn/understand better " visually "

>

>

> #39 -- IV infusion order is received for aminophylline 500mg in

> 500ml of D5W to be infused at 1mg/kg/hr. pt. weighs 154lb. what is

> flow rate in ml/min?

>

> #48 -- IV infusion order received for lidocaine 2g in 250ml of D5W

> to be infused at 3mg/min. flow rate in ml/hr?

>

>

>