Amputation coding seems to bring more confusion, and more potential gray areas, than most.
There is the ongoing discussion about what code is correct for aftercare of surgery for amputation, and more recently, there has been a lot of discussion on what code works to indicate a complication of an amputation stump.
The straight-up coding seems simple:
- The infected amputation stump is coded to 997.62. Note the Use Additional Code instruction at Category 997 to add the infection, if it is known.
- Dehiscence of an amputated stump would be coded to 997.69, Other late amputation stump complication.
But what about disruption of wound codes? A dehiscence certainly is a disruption. Can it be used instead of 997.69? This is where knowing how to use your code book can save you from errors. If you look at 998.31, Disruption of internal operation (surgical) wound, you’ll see an Excludes note for the 997 codes. But look at the official coding guidelines:
” … If the complication is classified to the 996-999 series and the code lacks the necessary specificity in describing the complication, an additional code for the specific complication should be assigned.” (Section II: Selection of Principle Diagnoses, section G)
What to do?
A group of coding experts recently queried AHIMA to find out.
First, we got a clarification that the Centers for Disease Control and Prevention believes that the dehiscence of an amputation site is different from dehiscence of a “standard” operative wound. Because of that distinction, the 998.3x codes are not considered appropriate for the dehiscence of an amputation site.
What about the Use Additional Code note? Remember that you should only assign that additional code if it provides additional information. 998.3x cannot be used as an additional code for 997.69 because 998.3x is only used for non-amputation stump dehiscence. It doesn’t add anything. Contrast that with Late effects of CVA, 438, a great example of a category where a Use Additional Code can paint the picture of the patient with two codes.
What about the Excludes note at 996.7x that excludes 998.31, but not 998.32? This subcategory is for “other complications of internal (biological) (synthetic) prosthetic, device, implant and graft.” 996.7x and 998.31 are both for “internal.” External disruptions, such as a stump dehiscence, don’t apply to this area, and 998.32 is external, as well.
Now, which set of instructions should be followed … coding guidelines or instructions in the Tabular? AHIMA is clear that instructional copy supersedes coding guidelines or Coding Clinic advice.