Patient has hypertension for which she takes medications and it is well controlled, but not related to the reasons for admission. Code this, because even if not part of the reason for the current admission, the hypertension IS relevant to this person's chronic medical situation and thus SHOULD be coded, as a comorbid.
Dx was present prior to physical arrival in their bed on unit/ward
AND
Dx is relevant to this admission in that it is either: (a) an acute or exacerbated condition (as opposed to a chronic, stable condition -- e.g. stable diabetes), OR (b) it is a condition that is not related to the reason(s) for admission and is still receiving "acute" treatment.
Example of 'a':
Example:
Patient admitted with a CAP to ICU who was intubated, ventilated and placed on antibiotics. They develop Atrial fibrillation and/or atrial flutter and are placed on meds which may need adjusting because they are still having breakthrough rapid Afib. Once extubated they are often ready for the medicine ward but are still on antibiotics for their CAP and require watching to see if their Afib returns. The medicine collector would list both CAP and Afib as part of their admitting diagnoses.
Patient with BPH who is not on any medications for it. They still have BPH but it is not an active problem being treated and so would be a Comorbid Diagnosis
Patient with diabetes admitted for an leg fracture. Here the diabetes is stable and (of course) treated during admission, but should be coded as a Comorbid Diagnosis.
Example of 'b':
Example:
Tuberculosis is an admit diagnosis in a person admitted with an acute MI, but still getting the 9 months of treatment for active tuberculosis.
Example of NOT an Admit Diagnosis:
Example:
Past h/o A-fib that's present but stable and getting the same treatment it has been for awhile. This is just a Comorbid Diagnosis
Dx is chronic (which includes NOT being fully resolved) and was present prior to admission
Code these even if the diagnosis of the condition was only made during the current hospital admission but it is quite clear that it must have existed before admission (even if that wasn't known). Here are some examples of that situation:
Example:
If a patient is admitted with pneumonia and on further workup is found to have CA of the lung, then this is coded in comorbid as it is obvious that the cancer must have been there for a while prior to admission.
Patient comes in with abdominal pain. Diagnosed as gastroenteritis but incidentally pt is found to be HIV +ve. You would code HIV +ve as a comorbid. Again, this is obvious that the pt had this problem for a while prior to admission to the hospital.
Some diagnoses can/should be coded as BOTH admit and comorbid:
example: Patient who has been, and still is, being treated for active pulmonary TB as an outpatient, and is admitted for an acute MI. Here since on the current admission the TB is still being actively treated, it qualifies as an admit diagnosis, as above. But because it has been present from long before this admission, it also qualifies as an "active" comorbidity.
Recurrent conditions
Do not code recurrent acute conditions that resolve between recurrences; for these, if currently active, include as Admit Diagnosis, otherwise don't code them.
Example:
Recurrent pneumonia -- although one can be left with chronic sequelae of pneumonia (e.g. a pneumatocele or a region of emphysema or a bulla), in between these infections, there IS NO pneumonia
Recurrent severe sepsis -- same as above
Do code conditions that by nature have intermittent rather than continuous symptoms, but where the underlying condition doesn't go away.
Example:
Asthma, without acute exacerbation -- this 'is a chronic disease whose nature is intermittent symptoms, but in between those symptoms the person still has asthma.
Category:Past medical history contains codes that should only be captured as Comorbid Diagnosis that represent previous procedures or medical situations that can't be captured in another way. Their names usually follow the pattern "Past history of X" or "Artifical opening, has one".
When a diagnosis can be coded as BOTH a comorbid and either acute or acquired
This may occur
Example:
*Patient has a past history of CHF and thus it should be coded as a comorbid. And if the CHF is worse at admission and it is part of the reason for admission, then CHF should also be an admit code too. If instead, CHF is stable at admit, but worsens after admit, then the CHF could be an acute/acquired diagnosis
This wiki page talks about which ICD10 codes are allowed to be Comorbid vs. Acute vs. Acquired diagnosis type. See Controlling Dx Type for ICD10 codes for a discussion about cross-checks for these.
