R65.21 — Severe sepsis with septic shock
R65.21 is a billable, specific ICD-10-CM code for severe sepsis with septic shock. It is valid for submission on a claim.
Excludes1 — never code together
These conditions cannot occur together. Billing both on the same encounter is a denial.
- postprocedural septic shock (T81.12-)
Other codes that can never be billed with R65.21
These codes carry an Excludes1 note pointing at R65.21. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading R65.21 alone.
Risk adjustment
R65.21 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:
- HCC 2 Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock0.500 RAF
Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.
Medicare coverage
R65.21 is named in 34 Medicare coverage policies — 34 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A52868Billing and Coding: Transesophageal Echocardiography (TEE)
- A56421Billing and Coding: CT of the Abdomen and Pelvis
- A56500Billing and Coding: Cardiac Catheterization and Coronary Angiography
- A56505Billing and Coding: Transesophageal Echocardiography (TEE)
How R65.21 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to R65.21.
- Severe sepsis›with septic shock
- Shock›endotoxic
- Shock›gram-negative
- Shock›septic(due to severe sepsis)
- Sepsis›severe›with septic shock
- Infection, infected, infective›with›organ dysfunction›with septic shock
- Sepsis›with›organ dysfunction›with septic shock
Related codes at this level
Codes that share R65.2. If R65.21 is not quite right, the correct code is usually one of these.
Questions about R65.21
- Is R65.21 a billable ICD-10-CM code?
- Yes. R65.21 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does R65.21 sit in the tabular list?
- Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99), in the block General symptoms and signs (R50-R69).
- What cannot be coded together with R65.21?
- R65.21 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.