Indications for diagnostic testing

zenman · Jun 20, 2009

Uh, they didn't cover that in school?

Trauma Columnist · Jun 20, 2009

Nope - they don't! I've only been out of school a year and here are some guidelines I use:

1. I look at the overall presentation: is it more soft tissue in some weird place or is it RUQ pain that is worse after eating? Then I would get a GB sono.

2. If the pt has an injury to a bony structure - I get a CT.

3. If the pt has pain/injury to a bony structure and they have cancer - I either CT or MRI it - much depends on their insurance for this one

4. If in doubt - ask.

Are you in primary care?

Dr. Tammy, FNP/GNP-C · Jun 20, 2009

The radiologist is your friend. Depending on what you are trying to rule out or in, they can offer exceptional advise. They are also great at adding to your differentials.

johnson0424 · Jun 22, 2009

Nope - they don't! I've only been out of school a year and here are some guidelines I use:
1. I look at the overall presentation: is it more soft tissue in some weird place or is it RUQ pain that is worse after eating? Then I would get a GB sono.
2. If the pt has an injury to a bony structure - I get a CT.
3. If the pt has pain/injury to a bony structure and they have cancer - I either CT or MRI it - much depends on their insurance for this one
4. If in doubt - ask.
Are you in primary care?

thanks trauma, yes i am in primary care and i had a lady w/ a hard lump on her jaw and i ordered a sono and the rad. called me back and stated i needed a ct...i felt like a totally idiot...

Trauma Columnist · Jun 23, 2009

Not at all. I often call the radiologist at the large teaching hospital that I refer to and they are excellent - that was a great suggestion Tammy!

I use a sono for more soft tissue things and CT for more bony issues. Another way to go is to get plain films - either a facial bone series or panarex and then when you get the radiologist's report, you can at least figure out (hopefully) if it is bony or some kind of lymphadenopathy, mass, etc.

JDCitizen · Jun 23, 2009

Nope - they don't! I've only been out of school a year and here are some guidelines I use:
1. I look at the overall presentation: is it more soft tissue in some weird place or is it RUQ pain that is worse after eating? Then I would get a GB sono.
2. If the pt has an injury to a bony structure - I get a CT.
3. If the pt has pain/injury to a bony structure and they have cancer - I either CT or MRI it - much depends on their insurance for this one
4. If in doubt - ask. !! !! !! !!
Are you in primary care?

So, so true about talking with the radiologist. The radiologist can be a wealth of information and there

are numerous different x-ray techniques that often can be used that can give you the information

needed without the expense of CT/MRI. I have saved many of my patients time, money and

aggravation by making one simple phone call.

No one can be a know-it-all so my suggestion is don't hesitate to pick up the phone and consult :-)

Your question has merit. Example: IVP or CT for a suspected kidney stone? Depends on provider and may depend on the radiologist and/or may depend on hospital policy.

Experience: IVP missed a stone the spiral CT didn't. Cost to patient two days of extra pain, the

expense of two tests and the need of follow up renal panels... Result: A hospital changed its policy.

silas2642 · Jun 23, 2009

I am a new fnp and I am having trouble knowing which test to order for example a ct vs a sono is there any guidelines anyone has to make this easier

Well, asking the radiologist or a physician seems like a good start. I'm just a med student, but we were taught that you should definitely have a pretty good differential in your mind before you start ordering expensive exams. So with your differential in mind, you could always look it up online from a source like diagnosaurus (I think this is the spelling) or uptodate. Usually they will give what tests are the the gold standard along with what other diagnoses you should be considering. You could also look it up in Harrisons. A lot of hospitals will have it online and most, if not all offices will have a copy in the office. Computer would probably be the fastest way to access these sources, but you could also access them via pda (heard the new iphone is pretty quick).

JDCitizen · Jun 24, 2009

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or Epocrates :-)

wowza · Jun 24, 2009

So, so true about talking with the radiologist. The radiologist can be a wealth of information and there
are numerous different x-ray techniques that often can be used that can give you the information
needed without the expense of CT/MRI. I have saved many of my patients time, money and
aggravation by making one simple phone call.
No one can be a know-it-all so my suggestion is don't hesitate to pick up the phone and consult :-)
Your question has merit. Example: IVP or CT for a suspected kidney stone? Depends on provider and may depend on the radiologist and/or may depend on hospital policy.
Experience: IVP missed a stone the spiral CT didn't. Cost to patient two days of extra pain, the
expense of two tests and the need of follow up renal panels... Result: A hospital changed its policy.

I was under the impression the CT was the test of choice and the current standard of care unless a helical CT is unavailable.

JDCitizen · Jun 24, 2009

I was under the impression the CT was the test of choice and the current standard of care unless a helical CT is unavailable.

True. But the test of choice does not always reach into every hospital policy or practice setting :-) The "we have been doing it this way for years" is not always an easy thing to overcome especially in rural settings.

Kind of off subject for this line of discussion but anyway:

I often see where the standard of care is not followed by providers on all levels of patient treatment (HTN, DM, HIV, Hepatitis, CAD, etc.) Age of provider I have seen also seems to have some bearing on the type of testing ordered. Sometimes I just have to ask some of my fellow providers why they ordered a certain test and not another....

Often standards of care have to be adjusted to real world. If one suspects a stone, everything points to a stone and the patients pocketbook may not support the expense of testing. What to do??

KUB?

IVP?

CT?

Hydrate to the max?

Cross your fingers?