Because there’s only one ICD-9 code for atrial fibrillation and it’s not a complication or comorbidity (CC), coders generally take it at face value. That will change when ICD-10 takes effect on Oct. 1, 2014, when physicians have the opportunity to describe the atrial fibrillation as paroxysmal, chronic or persistent.
If it’s documented and coded as “persistent,” atrial fib is a CC, which may generate more MS-DRG reimbursement. But getting there could require more querying, so hospitals may want to slip a few more words into queries now to get physicians accustomed to being more specific in their documentation when ICD-10 goes live.
That’s one example of how ICD-10 will change the way that hospitals think about diagnoses and procedures, with procedure codes in particular undergoing a complete overhaul. The common denominator is the need for more specific documentation in the medical records, including more detail in the operative episodes. Improvements hospitals make now will bear fruit in the future and may have immediate benefits in the remaining months under ICD-9.
“Plant the seeds for physicians,” says consultant Sandra Routhier, a certified coder and former hospital information management director. For example, she says, “start introducing ICD-10 terms into queries.”
ICD-10 coding is divided into diagnosis codes (ICD-10-CM) and procedure codes (ICD-10-PCS). “The diagnosis piece of ICD-10 is like ICD-9 on steroids because,” Routhier says, “there is more specificity, code description revisions and some codes were moved to new chapters. But all in all, the classification systems are very similar.”
ICD-10 Requires New Strategies
ICD-10-PCS, however, is a “whole new ball of wax. It’s a very different classification system for procedural coding, and that’s where I fear for hospitals.” Surgical procedures tend to be high-volume and high-weighted MS-DRGs, which means they generate more reimbursement than medical MS-DRGs, she says.
ICD-10-PCS requires physicians to document the objective of the procedure (which is the “root operation” of the PCS code), as well as the body part, the surgical approach, and whether any device was inserted.
Physicians must be very specific in their operative reports to ensure accurate ICD-10-PCS and MS-DRG assignments, Routhier says. Suppose a patient presented with an incarcerated incisional hernia. During the open hernia repair, the surgeon stated that “an area of approximately 3 cm of ischemic necrotic bowel was found.”
The procedure was listed on the operative report as “repair of incarcerated incisional hernia with partial small bowel resection.” The coder reviewed the operative report, but there was nothing about which portion of the small bowel (duodenum, jejunum or ileum) was removed.
How would it be coded now vs. under ICD-10? Routhier explains the differences:
- ICD-9-CM: Procedure code 45.62 is the only code option that exists for reporting the partial resection of the small intestine for this scenario. As a result, the hospital would assign MS-DRG 331 (major small & large bowel procedures without CC/MCC) with a relative weight of 1.6380.
- ICD-10-PCS: Removal of the small intestine can be classified to the root operation of excision (cutting out or off a portion of a body part) or resection (cutting out or off all of a body part), Routhier says. The specific body part values available for assignment of the 4th character of the PCS code include duodenum, jejunum and ileum. The root operation (excision or resection depending on whether all or a portion of the body part was removed) and the specific body part (the small bowel — duodenum, jejunum or ileum) excised affects the DRG assignment. There are a few MS-DRG options if the partial small bowel resection was further specified by the surgeon, depending on what he or she documented. They include:
(1) A portion of the duodenum body part: Assignment of procedure code 0DB90ZZ for excision of duodenum using open approach would result in MS-DRG 328 (stomach, esophageal & duodenal procedures without CC/MCC) with a relative weight of 1.4765.
(2) All of the duodenum body part: Assignment of procedure code 0DT90ZZ for resection of the duodenum using open approach would result in MS-DRG 331 (major small & large bowel procedures without CC/MCC) with a relative weight of 1.6380.
(3) A portion of the jejunum body part: Assignment of procedure code 0DBA0ZZ for excision of jejunum using open approach would result in MS-DRG 349 (anal & stomal procedures without CC/MCC) with a relative weight of 0.8834.
(4) All of the jejunum body part: Assignment of procedure code 0DTA0ZZ for resection of the jejunum using the open approach would result in MS-DRG 331 (major small & large bowel procedures without CC/MCC) with a relative weight of 1.6380.
Physicians Must Connect the Dots Under ICD-10
For their part, ICD-10-CM diagnosis codes require significant changes in documentation. For example, physicians may fail to link a patient’s diagnosis with underlying causes or manifestations in their documentation, Routhier says. Because ICD-10 has combination codes — a single code that includes both diagnosis and the cause or manifestation — the stakes are higher for physicians to link them. For example, under ICD-9 coders use two codes to report diabetes with renal nephropathy — one code for diabetes with renal manifestations and one code for the manifestation (e.g., nephropathy) — but there is one combination code in ICD-10. Sometimes doctors write diabetes and nephropathy as diagnoses but don’t connect the dots with phrases like “due to” or “associated with.”
Sometimes the ICD-10 classification system itself affects final MS-DRG reassignment, she says. For example, hypertension can be described as malignant, benign or unspecified. If it’s malignant (often called “accelerated”), hypertension is a CC, but that won’t be the case with ICD-10, which has one code for hypertension, she says. “From a coding perspective, it won’t matter anymore if the doctor says accelerated hypertension,” Routhier says. “We won’t bother physicians with a query to further specify this condition.”
