Part B Insider (Multispecialty) Coding Alert

Make sure you know the questions to ask to choose the proper code

Watch out: Don't get burned using the wrong set of burn diagnosis codes.

ICD-9 lists two distinct sets of diagnosis codes for burns, and in most cases you'll have to select a code from each set to describe the patient's condition properly. Before you assign a diagnosis code, you'll need to know the burn location, the burn degree and the percentage of body surface burned.

1. Location. First, you should use codes 941-946 "to code the burn by body location," says Lisa Center, quality coordinator with Freeman Health System in Joplin, MO.  For example, if a patient has a burn on her hand, you know to begin your coding with the 944 series.

2. Degree. When reporting a diagnosis from the 941-946 series, you must select a fourth digit, Center says. Codes 941-946 each list six fourth-digit options to indicate the degree of the patient's burn, including 0 (Unspecified), 1-3 (first, second or third degree), 4 (Deep necrosis of underlying tissues without mention of loss of a body part), and 5 (...with loss of a body part).

Important: You should code for only the highest-level burn when you report multiple burns of differing degrees (severity) in the same area.

3. Precise location: For ICD-9 codes 941-945, you must also assign a fifth digit to indicate the precise location of the patient's burn.

Example: The patient has a second-degree burn on his ankle. You would report 945.23 (Burn of lower limb[s]; blisters, epidermal loss [second degree]; ankle). Once again, higher-degree burns take precedence over lesser-degree burns in the same general anatomic area.

Uncover Rules for Unspecified Location

If the physician's documentation does not specify the location of the patient's burn but does indicate the extent of body surface burned, you should select a 948 code (Burns classified according to extent of body surface involved).

To report the correct 948 code, you must first select a fourth digit to indicate the percentage of total body surface burned, Center says. Then, you should use a fifth digit to indicate what percentage of the body includes a third-degree burn, says Linda Martien, coding consultant with National Healthcare Review in Woodland Hills, CA.

Avoid this mistake: Coders often stumble over the fifth digit for 948 because they mistakenly think the fifth digit indicates the percentage of the burned area that is third-degree. In fact, you should select the fifth digit that indicates the percentage of the total body area with third-degree burns.

If you use 948 because the physician did not specify location, but the patient has no third-degree burns, report 948.x0 (... less than 10 percent or unspecified) to indicate that there are no third-degree burns.

Last resort: If documentation doesn't specify a burn location or the extent of body surface burned, you have no choice but to report 949.x (Burn, unspecified) with the appropriate fourth digit to indicate the degree of the burn.

You can use ICD-9 code 946.x (Burns of multiple specified sites) to report "burns of sites classifiable to more than one three-digit category in 940-945," Martien says. CPT also states that 946 excludes "multiple burns NOS (949.0-949.5)."

Even though 946 is appropriate for multiple burn sites, most coding experts recommend this code as a last resort. You should not report 946 if you can code burns by specific area, Martien says.

Not only can you use 948 when the physician doesn't specify burn location, but you should also use 948 in addition to a burn location code (941-947) when the patient has a third-degree burn.

Remember: If a patient has  no third-degree burns, there is no need to report a 948 code in addition to the burn location code, Martien says.

Sequence matters: "In the case of multiple burns, sequence first the code that reflects the highest degree of burn," Center says.