Dermatology Coding Alert

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

With some diagnoses, there is clearly one code series to choose from -- unfortunately, that's not the case with burns.
 
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.

1. Determine the Burn Location

When assigning burn diagnosis codes, you'll need to know the burn location, the burn degree, and the percentage of body surface burned.
 
First, you should use codes 941-946 "to code the burn by body location," says Lisa Center, CPC, quality coordinator with Freeman Health System in Joplin, Mo.
 
ICD-9 divides codes 941-946 by the following locations:
 
• 941-- Burn of face, head, and neck
 
• 942 -- Burn of trunk
 
• 943 -- Burn of upper limb, except wrist and hand
 
• 944 -- Burn of wrist(s) and hand(s)
 
• 945 -- Burn of lower limb(s)
 
• 946 -- Burns of multiple specified sites.

For example, if a patient has a burn on her hand, you know to begin your coding with the 944 series.

2. Select a 4th Digit by 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:
 
• 0 -- Unspecified degree
 
• 1 -- Erythema (first degree)
 
• 2 -- Blisters, epidermal loss (second degree)
 
• 3 -- Full-thickness skin loss (third degree NOS)
 
• 4 -- Deep necrosis of underlying tissues (deep third degree) without mention of   loss of a body part
 
• 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.
 
Example: The patient has both first- and second-degree burns of the face. In this case, you should report only the more severe (second-degree) burns using the location code 941 and a fourth digit of 2.
 
If the same patient also had second- and third-degree burns on the left arm, you would report 943.3x in addition to 941.2x.

3. Choose the 5th Digit by 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).
 
Note: The fifth-digit categories are specific to the affected area. For example, a fifth digit of 1 when applied to 941.xx describes "ear [any part]," whereas a fifth digit of 1 when applied to 942.xx describes "breast."
 
Once again, higher-degree burns take precedence over lesser-degree burns in the same general anatomic area.
 
Example: For a third-degree burn on the chest and a first-degree burn on the stomach, report only 942.32 because both burns are on the trunk. But you may code an additional second-degree burn on the arm separately (943.23) because the arm is part of a different body area.

4. Choose 948 or 949 for Unspecified Location

If the dermatologist'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).
 
The basics: 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 surface includes a third-degree burn, says Linda Martien, CPC, CPC-H, coding consultant with National Healthcare Review Inc. in Woodland Hills, Calif.
 
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.
 
Example: The documentation does not note the location of a burn but does state the patient has burns on 20 percent of his total body surface. The documentation also states that half of the burned area (about 10 percent of the total body area) is third-degree burns. You would report 948.21 (Burns classified according to extent of body surface involved; 20-29% of body surface; 10-19%).
 
Consider this: If you use 948 because the physician did not specify the 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.

Use 946 Only if You Can't Be More Specific

You can use 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.

5. Report 948 for 3rd-Degree Burns

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.
 
Avoid extra work: 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.
 
Example: A patient presents with a small second-degree burn on her back and a burn covering most of her upper arm, 30 percent of which is a third-degree burn. You would first report 943.33 (Burn of upper limb, except wrist and hand; full-thickness skin loss [third degree NOS]; upper arm) and then 942.24 (Burn of trunk; blisters, epidermal loss [second degree]; back [any part]).
 
You should then also report 948.00 (Burns classified according to extent of body surface involved; burn [any degree] involving less than 10% of body surface; less than 10% or unspecified) to indicate the percent of total burn area that is third-degree burn.