CO-233: Hospital-Acquired Condition or Preventable Medical Error
A hospital-acquired condition reduced payment. Verify POA indicators and appeal if the condition was present on admission.
What Does CO-233 Mean?
With CO, the HAC reduction is contractual. Review POA indicators and appeal if the condition was present on admission.
CARC 233 indicates the payer identified a condition or complication that was acquired during the hospital stay (not present on admission) and reduced payment accordingly. Under CMS's Hospital-Acquired Conditions (HAC) Reduction Program and similar commercial payer policies, hospitals do not receive additional payment for certain preventable conditions that develop during the inpatient stay.
HACs include conditions like catheter-associated urinary tract infections, surgical site infections, falls, pressure ulcers, and other preventable complications. The Present on Admission (POA) indicator is critical — conditions present at admission are not subject to HAC reductions.
Common Causes
| Cause | Frequency |
|---|---|
| Hospital-acquired infection (HAI) identified The patient developed an infection during the hospital stay that was not present on admission, and the payer will not reimburse for treatment of the HAI | Most Common |
| Medicare HAC Reduction Program penalty Under Medicare's Hospital-Acquired Conditions (HAC) Reduction Program, payment is reduced for conditions acquired during the hospital stay | Most Common |
| Preventable medical error identified The payer identified a medical error during treatment that could have been prevented, and associated treatment costs are denied | Common |
| Condition not present on admission (POA) The diagnosis was identified as not present on admission through POA indicator reporting, triggering the HAC policy | Common |
| Never event occurred during treatment A 'never event' (serious preventable adverse event) occurred during the hospital stay, such as a wrong-site surgery or retained surgical object | Occasional |
How to Resolve
- Review POA coding Verify the condition's POA indicator.
- Appeal if POA was incorrect Correct POA coding and resubmit or appeal.
- Accept if correct If the condition was hospital-acquired, accept the reduction.
Appeal if the condition was present on admission or the hospital-acquired condition designation was applied in error. Include admission documentation (history & physical, admission lab results, imaging) proving the condition existed before admission, corrected POA indicators, and clinical narrative explaining the condition's origin.
Common RARC Pairings
The RARC code tells you exactly what triggered the CO-233:
| RARC | Description |
|---|---|
| N386 | This decision was based on a National Coverage Determination (NCD) or Local Coverage Determination (LCD). Review the CMS HAC Reduction Program guidelines and verify the HAC designation is correct → |
| N381 | Alert: Consult your contractual agreement for restrictions, billing, and payment information. Review your contract for HAC-related payment reduction policies → |
How to Prevent CO-233
- Ensure accurate POA indicator coding on all inpatient claims
- Implement HAC prevention programs
- Train clinical documentation improvement specialists on HAC documentation requirements
- Conduct regular audits of POA indicator accuracy
General Prevention
- Implement evidence-based infection prevention protocols to reduce hospital-acquired infections
- Ensure accurate Present on Admission (POA) indicator coding on all inpatient claims
- Document all conditions present at admission thoroughly in the admission notes
- Conduct regular quality improvement audits focused on HAC prevention
- Train clinical staff on surgical safety checklists and patient safety protocols
- Implement robust hand hygiene, catheter care, and fall prevention programs
Also Filed As
The same CARC 233 may appear with different Group Codes:
Related Denial Codes
Sources
- https://x12.org/codes/claim-adjustment-reason-codes
- https://www.mdclarity.com/denial-code/233
- https://portal.ct.gov/-/media/ohs/health-it-advisory-council/apcd-advisory-group/data-submission-guide-workgroup/meeting-materials/6-30-22/carc-codes_final.pdf
- Codes maintained by X12. Visit x12.org for official definitions.