Combined ICD10 codes

To code some diagnoses as part of ICD10 collection, several lines of entries in the Patient viewer tab ICD10 need to be grouped together.

To group diagnoses together, use the same Dx Priority for all of them.

Combined coding does not apply to CCI Collection (there is no priority), and there is nothing in the data that links a CCI code to the Dx it is related to.

Coding instructions

Introduction

• There are numerous situations in which multiple codes need to be listed in order to accurately reflect what's going on medically.
• For some situations the multiple codes need to be linked together (we use the term "combined").
• For other situations it's just a matter of ensuring that the multiple codes are all in the diagnosis list -- i.e. they don't need to be combined.
• There are some Dxs that can only be expressed as combinations, see #Some specific cases

Clinical Situation Plus its Cause

• Many ICD10 codes are for manifestations of disease, not a specific disorder per se.
• In their Wiki articles it will say something like "also code cause if known" e.g: Hematemesis
• If the cause is an infection, the Wiki article will instruct to "also code infection source", e.g: Shock, septic
• In general, when you have a manifestation and a cause, the two codes should be combined.
  • For example, in Septic Shock that has led to liver failure, the two should be coded with the same priority.

Primary Admit Diagnosis in Combined Codes

See Primary Admit Diagnosis

Dxs that can only be expressed as combinations

Some entities can only be coded with a combination of two codes.

Examples:

• retroperitoneal hemorrhage; code combined
  • Hemorrhage, NOS
  • Retroperitoneal area, diagnostic imaging, abnormal
• Hospital-acquired pneumonia (HAP) in ICD10

Some specific cases

Malignancy with Metastasis

Metastasis and their primary tumor should be coded in combination because the codes for mets don't specify the primary site, only the site of the mets.

Codes for the mets can be found at:

• If the site of the mets isn't in the list, use Site NOS, metastatic malignancy to it (also code primary site)
• If there are mets to multiple sites, then combine all together the primary malignancy code to the codes for the different sites of the mets.
• If the mets are in the other of a paired organ (e.g. the other kidney), then code both the primary and the metastatic codes, and link them together

Codes for the primary tumors can be found at:

Traumas and their Mechanisms

• In ICD10, traumas need to be combined with separate mechanism codes to fully explain the situation.

• Here are lists of the codes for "mechanical" injuries to various body parts:
  • some codes are always traumatic and always need a mechanism:

• Other codes may or may not be of a traumatic nature; these also qualify to be coded with trauma mechanisms listed below:

Potential trauma codes:

Lightning injury Respiratory tract, foreign body in

• Here is a list of the external mechanism or agent that caused the trauma:

Regarding Multiple Trauma

• When a person has multiple body areas traumatized, code Multiple trauma
• When using Multiple trauma also code the individual things traumatized, e.g. leg, arm, head, etc.
• Code Multiple trauma and all the individual things traumatized as Combined ICD10 codes
  • And in this case, assuming that they all have the same mechanism of injury (e.g. Mechanism of injury: motorcyclist), then you'd also code that Mechanism code as the same Combined ICD10 codes.
• If the multiple trauma is the primary admit diagnosis, then among this group of linked ICD10 codes, the Primary Admit Diagnosis would be either the Multiple trauma or the "worst" thing injured, e.g. Brain injury, diffuse (TBI), injury/trauma

Iatrogenic injuries

• Some iatrogenic codes are self-explanatory for what occurred. For example Iatrogenic, air embolism, as complication of line/infusion/transfusion/injection. But for others, such as Iatrogenic, puncture or laceration, related to a procedure or surgery NOS it's not clear what happened, i.e. what was iatrogenically injured.
  • In these latter cases, with just one exception, DO NOT also code a trauma code for what was iatrogenically injured. This is because iatrogenic injuries are technically not considered to be traumas.
    • that one exception is you should code Rib fracture(s) due to CPR in the context of CPR, cardiac resuscitation.
  • Instead, combine the iatrogenic code with another ICD10 code indicating the body part involved.
    • e.g. for iatrogenic laceration of a pulmonary artery, combine: Iatrogenic, puncture or laceration, related to a procedure or surgery NOS with Disorder of pulmonary vessels, NOS. See list of NOS codes in ICD10.

Infections

Infections in ICD10 have combined coding requirements for some of their pathogens. Any that have antibiotic resistances would store those as Combined ICD10 codes as well. If the infection is acquired in the hospital, see Nosocomial infection, NOS. See Lab and culture reports for confirmation and details about tests. See Infections in ICD10 for more general info.

Possible Simultaneous Presence of Multiple Different Types of Infection in a Single Site

• This refers to the situation where there may be simultaneous infection with multiple types of organisms -- e.g. 2 of bacteria, virus, fungus. While a classic example is a proven viral pneumonia (e.g. influenza) with a suspected/possible bacterial pneumonia superimposed, this kind of thing can occur in places other than the lungs, e.g. meningitis.
  • The "signature" of this is typically the patient being treated simultaneously with antimicrobial agents for multiple types of organisms. BUT don't confuse this with there being infections at DIFFERENT body sites.
• As per our usual practice, we will consider a diagnosis as present if the clinical team thinks it's present and are treating it, with the exception that the team initially treated for the possible 2nd type of infection but then decided it likely was NOT present and stopped those agents.
• And remember that Infectious organism, unknown is used when the the specific organism is unknown (this could be not knowing the TYPE of organism, or suspecting the type but not having identified the specific organism of that type), while when the organism has been identified but it's not in our bug list, THEN use Bacteria, NOS, Virus, NOS or Fungus or yeast, NOS.

Attribution of infections

See Attribution of infections

Antibiotic resistance

Antibiotic resistance is coded as Combined ICD10 codes of the condition/pathogen and the resistance. See Antibiotic Resistant Organism for more info.

Other co-codes

• In addition to the combined coding situations listed above, you can combine codes when it makes sense to you to do so. The general guideline should be that codes be combined (instead of just both listed in the diagnosis list) when they are strongly related to each other.
• Use your judgement. Either listing them separately, or combined ensures that they're all there.

Transition notes

Yes, this different from how we used to use dx priorities where they had to be unique.

Data

The records are combined by same L_ICD10.Dx Priority.