2026 ICD-10-CM Diagnosis Code P28.0Primary atelectasis of newborn
ICD-10-CM Codes›P00–P96›P19-P29›P28
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 213
- Not Chronic
P28.0 is a billable ICD-10-CM diagnosis code for primary atelectasis of newborn. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 791, 793. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 78 closely related codes. Coders also document this condition as perinatal atelectasis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Respiratory perinatal condition.
For Medicare Advantage risk adjustment, P28.0 maps to CMS-HCC Category 213 (Cardio-Respiratory Failure and Shock) under the V28 model, adding a risk factor of about 0.370 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
P28.0 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 2026.
Source: CMS Payment Year 2026 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.
- Perinatal atelectasis
- Primary atelectasis, in perinatal period
- Pulmonary hypoplasia associated with short gestation
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Primary failure to expand terminal respiratory units
- Pulmonary hypoplasia associated with short gestation
- Pulmonary immaturity NOS
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Apneumatosis, newborn P28.0
Fetus, fetal See Also: condition;
lung tissue P28.0
Immaturity (less than 37 completed weeks) See Also: Preterm, newborn;
lung, newborn P28.0
pulmonary, newborn P28.0
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Lung Diseases
When you breathe, your lungs take in oxygen from the air and deliver it to the bloodstream. The cells in your body need oxygen to work and grow. During a normal day, you breathe nearly 25,000 times. People with lung disease have difficulty breathing. Millions of people in the U.S. have lung disease.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert P28.0 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About P28.0Overview
What is the ICD-10 code for primary atelectasis of newborn?
The ICD-10-CM code for primary atelectasis of newborn is P28.0 (sometimes written as P280). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is P28.0 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report primary atelectasis of newborn on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does P28.0 group to?
When primary atelectasis of newborn is the principal diagnosis on an inpatient stay, it groups to MS-DRG 791, 793, with relative weights from 4.0590 to 4.1696 depending on complications. Higher weights mean higher Medicare reimbursement.
Is P28.0 a CC or MCC?
CMS lists P28.0 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 78 closely related codes in its exclusion list.
What is the ICD-9 equivalent of P28.0?
Under the General Equivalence Mappings, primary atelectasis of newborn converts to ICD-9-CM 770.4 (primary atelectasis). The mapping is a direct match.
What HCC is P28.0?
P28.0 (primary atelectasis of newborn) maps to CMS-HCC Category 213 (Cardio-Respiratory Failure and Shock), commonly written as HCC 213, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It does not map to any RxHCC in the Part D prescription drug model.
Does P28.0 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, P28.0 adds a risk adjustment factor of about 0.370 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.258 to 0.662 depending on the payment segment). A more severe related category (HCC 211 and HCC 212) supersedes it when both are reported. See the full factor table on the HCC 213 category page.
