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 not directly related to the reason(s) for admission, but its treatment is being actively managed -- and by actively we mean that during this admission changes are made to the management.
Examples:
Example:
Patient with TB has been treated for the past 5 (of his 9 expected) months admitted now for acute MI.
Scenario#1:No changes made in his TB treatment ---> so NOT an admit dx.
Scenario#2:Changes are made to his TB treatment during this admission ---> so IS an admit dx too
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.
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.
Recurrent conditions
Do not code a recurrent condition this is NOT currently present -- if currently active, include as Admit Diagnosis, otherwise don't code it
Example:
Recurrent pneumonia -- in between the infections, there IS NO pneumonia
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.
Past medical history
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".
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.
