ICD 10 Coding Alert

Look to underlying causes, know what to code first.

You may think that coding sleep apnea is a pretty simple task. But it's really not as easy as it seems. The disorder comes in different forms with different underlying conditions. And, in some cases, those conditions need to be coded first.

To cut through this confusion, we reached out to two veteran coders - Jill Young, CPC, CEDC, CIMC,  of Young Medical Consulting LLC in East Lansing, Michigan and Cynthia A. Swanson, RN, CPC, CEMC, CHC, CPMA, senior manager of healthcare consulting for Seim Johnson in Omaha, Nebraska - and asked them the most frequently asked questions coders have about this condition.

Here are their answers.

Q: When should you report G47.30?

A: Report G47.30 (Sleep apnea, unspecified) when a patient has nonspecific sleep apnea. "Sleep apnea is a common sleep disorder; a condition in which a person stops breathing periodically during sleep," Swanson explains.

Although G47.30 is for unspecified sleep apnea, you'll probably end up using it often. You often won't have a choice in the matter, Young says, as providers often don't give coders enough information to choose a more specific code. Go with the unspecified code when neither the diagnostic statement nor the documentation provides enough information to assign a more specific code, and you cannot ask the provider for clarification.

Q: What is the difference between G47.30 and G47.33?

A: You will use G47.33 (Obstructive sleep apnea [adult] [pediatric]) when the patient has obstructive sleep apnea.

Obstructive sleep apnea "is caused by partial or complete blockage of the airways during sleep. Symptoms of obstructive sleep apnea may include snoring that is loud, disruptive and regular; frequent breaks in breathing cause by an obstruction; morning headaches; restless sleep; and depression or irritability," explains Swanson.

Watch out: Sometimes, a provider diagnoses a patient with unspecified sleep apnea as an initial diagnosis. Then, after testing such as a sleep study, the provider might find that the patient's apnea is actually obstructive.

When the diagnosis changes from unspecified sleep apnea to obstructive sleep apnea, coders need to be ready to confirm the diagnosis change with the provider and make the proper adjustments to the patient's medical record. Young says that once patients are tagged with G47.30, the provider often forgets to update the diagnosis to G47.33 when necessary.

Q: What types of underlying conditions might accompany sleep apnea?

A:  The instructions below the descriptor for G47.3- read "Code also any associated underlying condition." According to Swanson, there are several causes and risk factors which can be associated with sleep apnea, including (but not limited to):

• obesity (E66.0- [Obesity due to excess calories...] through E66.9 [Obesity, unspecified]),
• enlarged tonsil or adenoids (J35.3 [Hypertrophy of tonsils with hypertrophy of adenoids]),
• frequent alcohol use (F10.1- [Alcohol abuse...] through F10.99 [Alcohol use, unspecified with unspecified alcohol-induced disorder]), and
• smoking (Z72.0 [Tobacco use]).

Remember: This is not an exhaustive list; there are many conditions that could underlie your patient's sleep apnea. If you see any of these diagnoses referenced in the encounter notes, however, be sure to include them on your claims for sleep apnea patients.

Q: So, for sleep apnea patients, I'll choose G47.30 or G47.33 as the diagnosis?

A: Not always. Though a lot of sleep apnea patients leave the practice with a G47.30 or G47.33 diagnosis, there are other forms of sleep apnea as well, represented by the following diagnosis codes:

• G47.31 - Primary central sleep apnea
• G47.32 - High altitude periodic breathing
• G47.34 - Idiopathic sleep related nonobstructive alveolar hypoventilation
• G47.35 - Congenital central alveolar hypoventilation syndrome
• G47.36 - Sleep related hypoventilation in conditions classified elsewhere
• G47.37 - Central sleep apnea in conditions classified elsewhere.

Best bet: Do your best to gain knowledge on all the forms of sleep apnea for coding purposes. That way, you can make a quick, and correct, decision the next time an apnea claim comes across your desk.

Q: Are there any other peculiarities common to sleep apnea coding?

A: There are several, but one of the most important overlooked aspects of sleep apnea ICD-10 coding concerns G47.36 and G47.37. Notes under both of these ICD-10 entries indicate that you should "Code first underlying condition." All of the other sleep apnea codes in the G47.3- code set instruct coders to "Code also underlying condition."

Explanation: According to ICD-10 rules, a "Code also underlying condition" note means that you might need two codes to fully describe a condition, "but this note does not provide sequencing direction," Swanson explains.

However, "certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology," says Swanson. In these instances, you should sequence the underlying condition code first.

So, when you report G47.36 or G47.37 along with an underlying condition, the sleep apnea diagnosis code must fall after the underlying condition code on the claim.

Note: Most payers have coverage requirements for services involving sleep apnea. Be sure to consult these policies for appropriate ordering and reporting guidelines, and minimizing the patient financial responsibility.