Q&A: Respiratory failure as a principal diagnosis

Q: When would respiratory failure be used as a principal diagnosis?

A: Let’s first start by looking at the definition of a principal diagnosis, per the Official Guideline for Coding and Reporting, Section II, it is:

“That condition established after study to be chiefly responsible for occasioning the admission of the patient to the hospital for care.”

So, any time acute respiratory failure meets the definition for the principal diagnosis, and is clinically supported in the medical record by a hands-on treating provider without any conflict existing in the documentation between any consulting and attending provider, then chances are respiratory failure would be coded as the principal diagnosis.

Now, we always need to go a step further and consider the circumstances of an admission, any diagnostic workup and/or therapy provided, and whether there any coding conventions, guidelines, or Coding Clinic recommendations that would affect our choice.  If there are none then the respiratory failure could be the principal diagnosis.

Respiratory failure is defined as abnormal arterial oxygenation and/or carbon dioxide accumulation. Diagnostic criteria include hypoxemic partial pressure of oxygen (pO2) less than 60 millimeters of mercury (mmHg) on room air or pO2/Fraction of inspired oxygen (FiO2) ratio less than 300, or 10mmHg decrease in baseline pO2 (if known). Hypercapnic pCO2 greater than 50mmHg with pH of less than 7.35, or 10mmHg increase in baseline pCO2 (if known).

The greater the specificity regarding the acuity and type of respiratory failure, the more accurate the coding staff can be with code assignment. We always want to encourage our providers to be as specific as possible based on the information available to them.

Editor’s Note: Sharme Brodie RN, CCDS, CDI education specialist and CDI Boot Camp instructor for HCPro in Middleton, Massachusetts, answered this question. For more information, contact her at sbrodie@hcpro.com. For information regarding CDI Boot Camps offered by HCPro, visit www.hcprobootcamps.com/courses/10040/overview.