General Surgery Coding Alert

Question: When I’m billing for bariatric surgeries, I’m having problems with denials that seem to indicate a lack of medical necessity. The surgeon always documents morbid obesity, and I always code it. What could be the problem?

Codify Subscriber

Answer: You are correct that morbid obesity is often the first diagnosis required to demonstrate medical necessity for bariatric surgery. But ICD-10 coding guidelines require you to report additional codes to further define the condition. And many payers also require evidence of co-morbid conditions that demonstrate specific ill-health effects of the obesity. Perhaps your claims are falling down on those additional reporting requirements.

Do this: Report first the code for morbid obesity (E66.01, Morbid [severe] obesity due to excess calories). ICD-10 then instructs you to use an additional code to identify the patient’s body mass index (BMI).

Next, you must report the appropriate code from the range Z68.1 (Body mass index [BMI] 19 or less, adult) to Z68.45 (Body mass index [BMI] 70 or greater, adult) to define the BMI of an adult patient. The codes specify BMI in increments of one unit. Many payers have a BMI level below which they will not cover bariatric surgery. If your surgeons aren’t providing this information in their reports, you should inform them that most payers require it.

Finally: Many payers expect you to show that the patient presents with at least one adverse health concern related to obesity. You should code only what your surgeons document, but the following list gives you an idea of the type of comorbidities that some payers expect to justify bariatric surgery:

• Hypertension — such as I10 (Essential [primary] hypertension)
• Type II diabetes — E11.- (Type 2 diabetes mellitus…)
• Coronary heart disease — such as I25.1- (Atherosclerotic heart disease of native coronary artery…)
• Stroke — such as I61.- (Nontraumatic intracerebral hemorrhage…).

Other comorbid conditions include gallbladder disease, osteoarthritis, sleep apnea, respiratory problems, and certain types of cancers.