Q&A: Respiratory documentation FAQs

Q: We see a lot of cases with only hypoxia documented where O2 saturation levels are initially in the 80s on room air with a P/F ratio < 300, but no other symptoms except shortness of breath or dyspnea are documented. Our CDI specialists are reluctant to query for acute respiratory failure because the symptoms are mild. I feel a query for acute respiratory failure is needed due to the P/F ratio and supplemental oxygen is required even if on only 2L/min. Can you clarify this?

A: We recommend a query for respiratory failure in these circumstances if not documented. O2 saturation (SpO2) < 91% on room air or P/F ratio < 300 on oxygen is a clear indicator of acute respiratory failure in patients who do not require continuous home O2. Shortness of breath or dyspnea represent respiratory difficulty consistent with acute respiratory failure when blood gas criteria are met. Supplemental oxygen even at 2 liters/min represents treatment of respiratory failure assuming the patient is not home O2 dependent.

Q: What about acute respiratory failure (ARF) being consistently documented, then doctors change shifts, the ARF drops off as a diagnosis as it is resolved, and the second doctor says they don't see failure and they document AECOPD or hypoxemia. We query and ask doctors to continue with “ARF resolved.” Is that correct?

A: Education of doctors to continue documentation of acute respiratory failure throughout the admission and discharge summary is encouraged, but not required. That said, if acute respiratory failure is documented at any point during the admission and is a valid diagnosis based on blood gas criteria, it should be coded based on:

• Official Coding Guidelines (OCG) Introduction: “The entire record should be reviewed to determine the specific reason for the encounter and the conditions treated.”
• OCG Section III: “All conditions that coexist at the time of admission, that develop subsequently, or that affect the treatment received and/or the length of stay.
• Coding Clinic, first quarter 2014, p. 11: “Documentation is not limited to the face sheet, discharge summary, progress notes, history and physical, or other report designed to capture diagnostic information.”

Q: Is an estimated P/F ratio value (using SpO2) an equivalent 1:1 to an ABG P/F ratio?

A: A qualified “Yes.” Only use the SpO2 for P/F ratio calculation when ABG is not available. In this situation, the SpO2 to pO2 conversion is the only objective measure; the relationship is approximate but should yield a very close P/F ratio estimate.

Q: Audit contractors cite Coding Clinics from 1988 and 1990 and Harrison’s Principles of Internal Medicine 2012 as diagnostic criteria for acute respiratory failure. Are there more recent clinical references from either critical care or pulmonary as a resource?

A: Coding Clinic is not a valid source for diagnostic criteria since Coding Clinic specifically disclaims any authority to establish any clinical diagnostic standards. See Coding Clinic, third quarter 2008, p. 16, and first quarter 2014, p. 11. The Harrison's textbook reference describes only the most extremely severe cases of acute respiratory failure verging on respiratory arrest, not less severe acute respiratory failure which is by far more common and defined by the blood gas parameters included in the CDI Pocket Guide.

Clinical references that substantiate the diagnostic standards for acute respiratory failure listed in the Acute Respiratory Failure section of the 2018 CDI Pocket Guide include:

• Medscape: Respiratory Failure: www.emedicine.medscape.com (updated on 9/19/17)
• Management of acute ventilatory failure. Postgrad Med J 2006; 82:438-445

Another is www.UpToDate.com (subscription required) "Evaluation, diagnosis, and treatment of acute hypercapnic respiratory failure (updated 7/20/17)

 You may also want to consider the CDI Pocket Guide and ACP Hospitalist Coding Corner as additional sources for audit appeals and even for physician education.

Editor’s note: This article also appeared on pinsonandtang.com. Richard Pinson, MD, FACP, CCS, and Cynthia Tang, RHIA, CCS, principals at Pinson and Tang, LLC answered these questions after their April 10, 2018, webinar, “Respiratory Failure: The Ins and Outs of Diagnosis Documentation, Coding, and Clinical Validation.” Pinson and Tang are the authors of the 2018 CDI Pocket Guide and the Outpatient CDI Pocket Guide: Focusing on HCCs.