2027 ICD-10-CM Diagnosis Code P91.9Disturbance of cerebral status of newborn, unspecified
P91.9 is a billable ICD-10-CM diagnosis code for disturbance of cerebral status of newborn, unspecified. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 791, 793. Coders also document this condition as abnormal cerebral sign in newborn. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neonatal cerebral disorders.
For Medicare Advantage risk adjustment, P91.9 maps to CMS-HCC Category 202 (Coma, Brain Compression/Anoxic Damage) under the V28 model, adding a risk factor of about 0.543 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
P91.9 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abnormal cerebral sign in newborn
- Perinatal nonspecific brain dysfunction
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to P91.9: its own notes plus those printed at Chapter 16. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- conditions that have their origin in the fetal or perinatal period (before birth through the first 28 days after birth) even if morbidity occurs later
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Notes
General instructions on how these codes are used.
- Codes from this chapter are for use on newborn records only, never on maternal records
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disturbance (s) See Also: Disease;
status, newborn P91.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Brain Diseases
Your brain is the control center of your body. It controls your thoughts, memory, speech, and movement. It regulates the function of many organs. It's part of your nervous system, which also includes your spinal cord and peripheral nerves. The nervous system sends signals between your brain and the rest of the body.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert P91.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About P91.9Overview
What is the ICD-10 code for disturbance of cerebral status of newborn, unspecified?
The ICD-10-CM code for disturbance of cerebral status of newborn, unspecified is P91.9 (sometimes written as P919). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is P91.9 (Other disturbances of cerebral status of newborn) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report disturbance of cerebral status of newborn, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does P91.9 group to?
When disturbance of cerebral status of newborn, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, with relative weights from 4.1073 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of P91.9?
Under the General Equivalence Mappings, disturbance of cerebral status of newborn, unspecified converts to ICD-9-CM 779.1 (NB cereb irrit NEC/NOS). The mapping is approximate, so confirm the match fits the documentation.
What HCC is P91.9?
P91.9 (disturbance of cerebral status of newborn, unspecified) maps to CMS-HCC Category 202 (Coma, Brain Compression/Anoxic Damage), commonly written as HCC 202, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It does not map to any RxHCC in the Part D prescription drug model.
Does P91.9 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, P91.9 adds a risk adjustment factor of about 0.543 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.097 to 0.721 depending on the payment segment). A more severe related category (HCC 63, HCC 397, and HCC 398) supersedes it when both are reported. See the full factor table on the HCC 202 category page.
