Hospital-acquired pneumonia (HAP) in ICD10

This page contains an ICD10 Coding Guideline for ICD10 collection. See ICD10 coding guidelines for similar pages.

Coding instructions

• HAP, Hospital-acquired pneumonia, is a category of nosocomial pneumonia that is contracted by a patient after at least 48 hours of being admitted to a hospital. In ventilated patients see Pneumonia, ventilator-associated to decide if it is a VAP or a HAP.
• To code HAP, you must use combined coding of 3 separate ICD10 codes:
  • (1) Nosocomial infection, NOS PLUS
  • (2) One of the codes for SPECIFIC TYPES OF PNEUMONIAS:
    • Pneumonia, bacterial
    • Pneumonia, fungal/yeast
    • Pneumonia, viral
    • Pneumonia, NOS
  • (3) relevant Pathogens, possibly Infectious organism, unknown or an NOS
• The concept of "early onset" HAP is not an accepted one (and not one we will use), because BY DEFINITION, to be HAP the patient must have been in hospital >48 hours and THEN developed the clinical signs/symptoms of pneumonia.
• To decide about whether a HAP (or a CAP) has occurred, requires clinical correlation.
  • For example, sputum is never sterile -- pathogen will always grow from it. It's even true that bronchoscopic lower respiratory samples are almost never sterile, which is why quantitative culture is used to interpet them. THUS, respiratory fluid that grows pathogens cannot by itself be used to interpret the presence of pneumonia EXCEPT in the rare cases of pathogens that are NEVER pathogens in the respiratory system -- that list is mainly limited to: TB, Legionella, and Pneumocystis jiroveci. Thus, a (+) sputum culture can almost never by itself be used to identify the presence of a pneumonia. Instead, it's a combination of clinical signs such as fever, leukocytosis and new (or presumed new) CXR changes that helps to figure it out. Indeed, one can diagnose CAP or VAP in the absence of a (+)sputum culture in the right situation (e.g. patient has been on antibiotics for some reason prior).

Attribution of the HAP to a Hospital Location

• The infection is attributed to the location where the patient was on the date the infection became clinically evident -- EXCEPT if all elements of the infection are present within the first 48 hours of arrival, the infection is attributed to the location from which they were transferred.

Alternate ICD10s to consider coding instead or in addition

• Pneumonia, ventilator-associated (VAP)
• Community-acquired pneumonia (CAP) in ICD10

Additional Info

• If there is insufficient criteria for a Pneumonia, ventilator-associated (VAP) in ventilated patients with positive cultures, the patient may still have HAP.
• Patients from Grace Nursing Home Ward - even though this is considered a nursing home type ward, for patients who acquire a pneumonia and meet the HAP criteria code HAP.

Don't need to follow VAP Guidelines for this

Do you need to follow the same guidelines for acceptable sources for cultures like for the VAP cultures?

• AG REPLY -- for HAP, no. Indeed, the main thing that distinguishes a CAP from a HAP is whether the patient has been in a LOCATION that qualifies for it being a HAP.

RE:A Patient with CAP on Admission

Can a patient with unresolved CAP ever be coded as HAP if ETC cultures become positive for a new pathogen or is it always going to be CAP?

• AG REPLY -- this is a very difficult clinical determination. Since our ability to identify the lung pathogen in ANY type of pneumonia isn't that good (even WITH bronchoscopy and quantitative BAL or protected specimen brush, which is almost NEVER done in Winnipeg) it is very very difficult to tell whether a new pathogen is a new infection. This is especially true since it is well known that hospitalized and intubated patients quickly get colonized in their airways with bugs that don't usually live there (e.g. gram negative rods) -- thus again just identifying a new bug in sputum that is a POTENTIAL pathogen is far from a diagnosis that that potential pathogen is actually the bug for an actual pneumonia or bronchitis. Thus, there can be no real rule here. It IS possible to get a new HAP/VAP after being admitted for a CAP, and even without cure of the CAP, but that determination requires things like: 1-A new potential pathogen PLUS 2-chest imaging that shows infiltrates in an area that was virtually COMPLETELY clear before PLUS 3-a clinical decision about this whole thing.

If a patient with CAP on admission that hasn't cleared but isn't ventilated for days then has to go on a ventilator less than 48 hour ventilated develops a positive culture (quantitive bronchoscopically obtained) and a change in respiratory status can this be called HAP? Or are you saying it's CAP the whole admission? It seems according to the VAP quidelines patients with CAP can develop VAP under the right conditions so couldn't they also get HAP? Are you saying patients with CAP can never get HAP?

I will give an example cases:

• The pt has CAP no culture is sent. The patient is in the ICU for 8 days not on a ventilator. The ventilation status gets worse. The CXR continues to have persisent infiltrates. The pt gets intubated and less than 48 hours on a ventilator a bronchoscopy is done and both ETC and quantitive cultures grow aspergillos. Is this still CAP or can it be called HAP?

• Same scenario as above occurs but a patient isn't treated for what ever pathogen grows in the cultures. Do we code the pathogen or not. Do we call it colonization or ignore the culture?
• AG REPLY -- as I've said above, it IS possible to get a VAP or HAP superimposed on a CAP -- but making that diagnosis is very difficult, requires clinical judgement and SHOULD require the 3 items I've listed above.

Aspiration and development of pneumonia less than 48 hours

Scenario: What do we code if a patient didn't have pneumonia on admission and came in for some other reason. They aspirate on intubation less than 48 hours in hospital and develop pneumonia. How do you code that? Is it CAP?

Code as: In most circumstances, an aspiration event DOES NOT cause an actual lung infection in <48 hrs. The entity you're describing (an aspiration event followed quickly by new infiltrate, and possible also new fever and leukocytosis, is an Aspiration pneumonitis -- see that article for some guidance on this question.