Hint: Coding for medical necessity in ASCs may smooth payer interactions. Ambulatory surgery centers (ASC) have a different feel and purpose than a traditional physician’s office, but insurers expect and require accurate coding. Coding for medical necessity — and therefore demonstrating the accuracy required for payment — is easy when you assign the correct ICD-10 codes to your claims. Consider the following best practices when you report diagnosis codes for these conditions, which are commonly seen in the ASC. Check These Diagnoses for Screening Colonoscopy If you see a patient in the ASC for a screening colonoscopy, you should report Z12.11 (Encounter for screening for malignant neoplasm of colon) on your claim. However, keep in mind that if the physician initially intends to perform a screening service but ends up finding something such as a polyp that creates a diagnostic service, a second code will be required. You need to be accurate on sequencing ICD-10 codes for a screening colonoscopy that ends up therapeutic, and would report the claim as follows: If, however, you’re performing a diagnostic colonoscopy from the start, you’ll report a definitive diagnosis when your gastroenterologist has performed a procedure and the results confirm the condition. Example: The gastroenterologist conducts a colonoscopy and confirms a diagnosis of Crohn’s disease with rectal bleeding. In this case, you should report K50.911 (Crohn’s disease, unspecified, with rectal bleeding) as the primary diagnosis for the colonoscopy. However, if your gastroenterologist performs a procedure and the evidence is inconclusive, you should fall back on signs and symptoms. For instance, if, during the colonoscopy, the gastroenterologists finds results negative for Crohn’s disease, you should rely only on the signs and symptoms to establish medical necessity for services the doctor provides. Know When to Assign Which Dx Physicians typically perform upper GI services to diagnose conditions after patients complain of symptoms. In some cases, the gastroenterologist will have a diagnosis in mind, but it’s important to never report suspected or rule-out diagnoses on claims. Instead, you’ll submit a claim using the final diagnosis (when applicable), or the signs and symptoms (when no diagnosis is confirmed). For instance, suppose the GI physician performs an upper GI service because he suspects that the patient is suffering from Barrett’s esophagus, but the doctor ultimately finds a gastric ulcer that he attributes to the patient’s long-term use of ibuprofen. The physician does not confirm Barrett’s esophagus. In this situation, you’ll report the primary diagnosis with K25.9 (Gastric ulcer, unspecified as acute or chronic, without hemorrhage or perforation). In addition, you should add Z79.1 (Long-term [current] use of non-steroidal anti-inflammatories [NSAID]) as your secondary diagnosis. Fall Back on Signs, Symptoms Sometimes In the absence of a definitive diagnosis, you should report signs and symptoms to support medical necessity for services your gastroenterologist provides, in situations such as the following: Some signs and symptoms you might see in a gastroenterologist’s documentation include upper abdominal pain (such as R10.10), diarrhea (R19.7), flatulence (R14.3), gas pain (R14.1), nausea (R11.0), and nausea with vomiting (R11.2).