Q&A: Sleep Apnea Clarification Opportunities

Q: Should I query for chronic respiratory failure if the documentation indicates the patient has sleep apnea and is being treated with continuous positive airway pressure (CPAP) at night?

A: I love where you are going with this question, it demonstrates your critical thinking, one of the most important skills a CDI specialist can have.

First off, let’s think about the definition of respiratory failure and the biological processes which cause it. Respiratory failure can result from an inability to ventilate (take in oxygen, expel carbon dioxide) or an inability for the gas exchange to occur at the cellular level within the lungs.

The Merck Manual describes it as:
“A rise in [partial pressure of carbon dioxide] PaCO² (hypercapnia) that occurs when the respiratory load can no longer be supported by the strength or activity of the system. The most common causes are acute exacerbations of asthma and [Chronic Obstructive Pulmonary Disease] COPD, overdoses of drugs that suppress ventilatory drive, and conditions that cause respiratory muscle weakness (e.g., Guillain-Barré syndrome, myasthenia gravis, botulism)… Treatment varies by condition but often includes mechanical ventilation.”

The Manual goes on to describe that the balance between load resistance to ventilation and neuromuscular competence (the drive to breath and muscle strength) determines the ability to sustain alveolar ventilation. Sleep disordered breathing is listed as a contributing condition that can disrupt this balance.

If you come from case management experience, you might be aware that for a Medicare patient to qualify for CPAP, a sleep study must be performed that demonstrates need based on the number and length of episodes occurring within the study elapsed time.

If the patient is receiving treatment or monitoring within the hospital stay to address the sleep apnea, a query may be warranted. Make sure the hospital is providing CPAP support at night and review the respiratory therapy notes to show consistency within the record before submitting the query.

If your organization does not have agreed upon diagnostic criteria for chronic respiratory failure, work with your CDI team and pulmonologists to define this condition and identify clinical indicators to support the query. Discuss with the pulmonologist how sleep apnea and the use of CPAP supports this diagnosis.

When I was reviewing records I always thought of obesity alveolar hypoventilation syndrome (Pickwickian’s Syndrome) as a possible secondary diagnosis where obstructive sleep apnea was listed as a diagnosis. Check the patient’s BMI and if you have morbid obesity, consider whether that condition led to the obstructive sleep apnea. This also provides a CC.

Smart question and this is often a query opportunity that is overlooked.

Editor’s Note: CDI Boot Camp Instructor Laurie Prescott, RN, MSN, CCDS, CDIP, AHIMA Approved ICD-10-CM/PCS Trainer, answered this question. Contact her at lprescott@hcpro.com. For information regarding CDI Boot Camps offered by HCPro visit www.hcprobootcamps.com/courses/10040/overview.