right and left foot perfusion

[PRijnbeek]

For diabetes control we have a large number of measurements of right and left foot perfusion.

Any guidance where this should be mapped to is welcome.

p.s. do these questions belong here or somewhere else?

Thanks.

[cgreich]

What's the measurement, @PRijnbeek? Are you looking for "Diabetic foot"? That is a Condition. There is not much of Measurements to determine that, it's a diagnosis based on signs and symptoms revealed through examination.

Or do you have some special tests like videomicroscopy?

[PRijnbeek]

:0 i know that.

It is as i state in the post. The Measurement of the perfusion in the foot. There is no condition here.

For example: https://www.researchgate.net/publication/283570256_Assessment_of_foot_perfusion_in_patients_with_diabetic_foot_ulcer

[cgreich]

Right. So, you got examination and interviewing the patient. No procedures or measurements for that. The measurements mentioned are:

• Transcutaneous oxygen tension: https://athena.ohdsi.org/search-terms/terms?domain=Measurement&standardConcept=Standard&page=1&pageSize=500&query=oxygen+%5Bpartial+pressure%5D%2A&boosts
• Ankle-brachial pressure index: https://athena.ohdsi.org/search-terms/terms/46237026
• Toe pressure index: https://athena.ohdsi.org/search-terms/terms/46236281

Cross-sectional imaging (x-ray, ct, mri, depending what you have), fluorescence angiography, capillaroscopy, iontophoresis and hyperspectral imaging are all procedures. Today we cannot process results of diagnostic procedures that are more complex and produce more than a simple value/unit result.

Bottom line: If you have a concrete measurement, put it in. Otherwise it is the result of complex decision making resulting in a diagnosis (=Condition).

[PRijnbeek]

Thanks i am expecting to get information about the unit of those "measurements" later today to answer your question.

[PRijnbeek]

its values are normal/abnormal/undetermined

[cgreich]

I would write the "Diabetic foot" Condition above if it is abnormal. If it is normal, or undetermined - drop it. Would that work?

[dimshitc]

Seems, perfusion should be drastically decreased for Diabetic foot to develop. What if they want to reflect slight decrease of a perfusion?

[PRijnbeek]

Exactly that would be too strong. That would require more information to then say Diabetic foot it would not be based on that measurement alone. For your background in the Netherlands these test are standard for any person that has the diabetes diagnosis. It is part of the care plan.

So it seems we do not have a good solution for this correct? We can keep it mapped to zero and use the source_concept_id for now. It would just bump our vocab mapping stats considerably and since we will be doing diabetes research it may become handy at some point.

[dimshitc]

@cgreich @Alexdavv what do you think of adding these Measurements to the OMOP Extension?

[MelaniePhilofsky]

Seems like this branch of SNOMED might be appropriate: https://athena.ohdsi.org/search-terms/terms/4161988

[dimshitc]

I can't see the exact perfusion of foot there. Or do you mean that we can extend this branch by an OMOP Extension concepts?

[Alexdavv]

Seems like this branch of SNOMED might be appropriate: https://athena.ohdsi.org/search-terms/terms/4161988

As long as we don't know how and what exactly was measured, this SNOMED Observable entity is a proper choice, I think.

There's another one pre-coordinated Condition. But it seems we'll split and map them over in the future.

If there's a need to be more specific to make a distinction between leg/foot and right/left, a new OMOP Extension concept would be a choice.

Bottom line: If you have a concrete measurement, put it in. Otherwise it is the result of complex decision making resulting in a diagnosis (=Condition).

I wouldn't be so strict about it. We have many abstractional Measurements here and there. And once SNOMED treat it as an observable entity, I would allow to use it with a value in the Measurement Domain. There's no a good way to differ them from the real Measurements anyway.

[cgreich]

So it seems we do not have a good solution for this correct?

@PRijnbeek, you need to find out what it is that they are testing. We have all the tests (see above). But a generic "no perfusion" is not a test, it is a conclusion=diagnosis. They must be testing something, and somebody will know.

As long as we don't know how and what exactly was measured, this SNOMED Observable entity is a proper choice, I think.

We don't know if it is arterial or capillary.

If there's a need to be more specific to make a distinction between leg/foot and right/left, a new OMOP Extension concept would be a choice

Agreed.

[p-talapova]

@PRijnbeek Just FYI. According to "The Best Practice Recommendations for the Prevention and Management of Peripheral Arterial Ulcers", for the assessment of foot perfusion physicians usually use ankle-brachial pressure index (ABPI). Resulsts can be interpreted as normal (1.0-1.2) and abnormal (mild arterial disease(0.8-0.9)/moderate arterial disease(0.5-0.79)/severe arterial disease(<0.5));

in OMOP, we have 1) standard procedures (all in SNOMED): 4295155 401221002 Ankle brachial pressure index 44805248 751071000000105 Left ankle brachial pressure index 44805247 751061000000103 Right ankle brachial pressure index 4295156 401222009 Left dorsalis pedis ABPI 4268437 401224005 Left posterior tibial ABPI 4268436 401223004 Right dorsalis pedis ABPI 4268438 401225006 Right posterior tibial ABPI

2) standard measurements: 40489833 446841001 Ankle brachial pressure index (SNOMED) 46237026 77194-9 Ankle-brachial index (LOINC)

[PRijnbeek]

Thanks that is helpful.