Question 1

What is ICD-10 code K91.0?

Accepted Answer

K91.0 is the ICD-10-CM diagnosis code for vomiting following gastrointestinal surgery. Vomiting that occurs as a complication after a patient has had surgery on their stomach or intestines. K91.0 sits in the ICD-10-CM chapter for diseases of the digestive system (k00-k95), within the section covering other diseases of the digestive system (k90-k95).

K91.0 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This code requires documentation linking the vomiting to a prior gastrointestinal surgical procedure.

Question 2

Is K91.0 an HCC code?

Accepted Answer

No. K91.0 is a billable ICD-10-CM code but does not map to any payment HCC category under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can still be reported on Medicare Advantage encounter data submissions, but it does not contribute to the beneficiary's Risk Adjustment Factor (RAF) score and therefore does not affect the risk-adjusted capitation payment to the plan. V28 reached 100% phase-in for payment year 2026.

Question 3

Is K91.0 billable?

Accepted Answer

Yes. K91.0 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. K91.0 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Question 4

What is the V28 vs V24 difference for K91.0?

Accepted Answer

K91.0 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither model rewards K91.0 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

Question 5

What should coders know when reporting K91.0?

Accepted Answer

This code requires documentation linking the vomiting to a prior gastrointestinal surgical procedure Distinguish from other postgastric surgery syndromes (K91.1) which may include additional symptoms beyond vomiting

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K91.0

Is K91.0 an HCC code?

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K91.0 ICD-10-CM Code: Vomiting following gastrointestinal surgery

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K91.0

Is K91.0 an HCC code?

What This Code Means

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Child Codes

Code Hierarchy

Open K91.0 in the Interactive Encoder