General Surgery Coding Alert

Centimeters count for some codes.

Duodenal switch, Roux-en-Y, limb length ... let us help you unravel the confusing language of bariatric surgery so you can chose the correct code -- and get the proper pay for your surgeons' work.

Know the context: Surgeons perform various gastric restrictive procedures for some patients with morbid obesity and co-morbid health conditions (see "Don't Count on Obesity for Medical Necessity" on page 58 in this issue). The procedures effectively reduce the stomach size to limit food intake and absorption, leading to weight loss. The most common gastric restrictive surgeries fall into two main categories -- bypass procedures (which we'll discuss here), and banding (which we'll discuss in a future article).

When you face an op note for gastric bypass surgery, simply decode the report and zero in on the suitable CPT® code by responding to these four questions.

Question 1: Is the Procedure Laparoscopic or Open?

Although this isn't the first question you'll need to answer, "the open/lap distinction leads to two distinct code sets for gastric bypass surgery," explains Marcella Bucknam, CPC, CPC-I, CCS-P, CPC-H, CCS, CPC-P, COBGC, CCC, audit manager for CHAN Healthcare in Vancouver, Wash.

The codes break down like this:

Laparoscopic codes:

• 43644 -- Laparoscopy, surgical, gastric restrictive procedure; with gastric bypass and Roux-en-Y gastroenterostomy (roux limb 150 cm or less)
• 43645 -- Laparoscopy, surgical, gastric restrictive procedure; with gastric bypass and small intestine reconstruction to limit absorption

Open codes:

• 43845 -- Gastric restrictive procedure with partial gastrectomy, pylorus-preserving duodenoileostomy and ileoileostomy (50 to 100 cm common channel) to limit absorption (biliopancreatic diversion with duodenal switch)
• 43846 -- Gastric restrictive procedure, with gastric bypass for morbid obesity; with short limb (150 cm or less) Roux-en-Y gastroenterostomy
• 43847 -- Gastric restrictive procedure, with gastric bypass for morbid obesity; with small intestine reconstruction to limit absorption.

Question 2: Is the Procedure -Ectomy Plus -Ostomy?

Only one common gastric bypass surgery actually involves removing a portion of the stomach (gastrectomy) -- the biliopancreatic diversion with duodenal switch. "Your surgeon might label the procedure 'BPD/DS,'" says M. Tray Dunaway, MD, FACS, CSP, a surgeon, author, speaker and coding educator with Healthcare Value Inc. in Camden, S.C. That means you need more than the name to make sure you choose the right code.

Key: The op note should describe removal of a portion of the stomach. For the duodenal switch, the procedure description should also note preservation of the pylorus and part of the duodenum with anastomosis between the duodenum and ileum.

You should report an open BPD/DS using 43845. CPT® doesn't provide a specific laparoscopic code for the procedure, although some surgeons perform it that way.

Best choice: "The best code choice for the laparoscopic procedure is either 43645 with modifier 22 (Increased procedural services) for the gastrectomy, or an unlisted code such as 43659 (Unlisted laparoscopy procedure, stomach)," Bucknam says.

Question 3: Is Stomach Subdivided, But Not Resected?

In addition to creating a gastric "detour," the most common gastric bypass surgery involves partitioning the stomach, usually with staples, without performing a partial gastrectomy. The intestinal reconstruction earns the procedure the name "Roux-en-Y," and you'll probably see that term in the op note.

Tip: Even without the name in the op note, if the bypass procedure includes stomach partitioning without removing a portion of the stomach and intestinal reconstruction, you're probably looking at a Roux-en-Y gastric restrictive procedure.

Procedure description: After partitioning the stomach, the surgeon cuts the small bowel and anastomoses the distal end of the intestine to the proximal stomach pouch -- this is the path that food will follow after surgery. Finally, the surgeon anastomoses the "unused" cut end of the small intestine to a more distal location of the small bowel.

Detour: As food travels from the proximal stomach pouch through the "short" intestinal limb, it "bypasses" the distal stomach and jejunal limb, thus restricting food intake and absorption due to a smaller stomach and shorter intestine.

Question 4: How Long is the Bypass?

You need to know the length of the intestinal limb that bypasses the stomach and jejunum because CPT® code selection depends on that measure.

"CPT® defines 'short limb' Roux-en-Y as 150 cm or less," Bucknam says. You have two code choices for a short limb Roux-en-Y, based on whether the procedure is laparoscopic (43644) or open (43846).

Intestine reconstruction: If the bypass procedure forms a longer intestinal limb (greater than 150 cm), the surgeon effectively "reconstructs" the intestine to limit absorption even more than the short-limb procedure. You also have two code choices for the intestinal-reconstruction procedure, based on whether the surgeon works laparoscopically (43645) or performs open surgery (43847).

Watch conversion: If the surgeon converts a laparoscopic Roux-en-Y to an open procedure, you can't code both. "Instead, you should report only the open code, although it would not be unusual to add modifier 22, because these procedures can become quite lengthy and often include extra work," Bucknam says.