Home Health ICD-9/ICD-10 Alert

Don't leave out vital details -- fourth and fifth digits are essential.

To accurately code diagnoses for patients with burn injuries, you need to know whether the patient had any third-degree burns. You also need to know when to combine multiple burns into one ICD-9 code and when to submit a separate code for each burn.

Check out this expert advice on burn diagnosis coding, and be sure you don't make some common home health coding mistakes.

1. Select the burn location: The first diagnosis code you'll select for burn victims represents the location of the burn (or burns) and its severity. You'll find these codes in the 940-947 ICD-9 set, says Trish Twombly, RN, BSN, HCS-D, CHCE, director of coding with Foundation Management Services in Den-ton, TX.

The codes in the 940-947 set require at least a fourth digit, and some require five. These codes break down the classification of the burn first by anatomic site and then by degree of burn.

Example: The physician's notes indicate that a patient suffered a first-degree burn to his chest wall. Based on this description, 942.12 (Burn of trunk; erythema [first degree]; chest wall, excluding breast and nipple) is the correct diagnosis.

Exception: The codes that extend only to the fourth digit (940.x, 946.x, 947.x) do not describe both burn severity and burn location. In these cases, just code based on what ICD-9 requires for the burn. For instance, look at 940.3 (Burn confined to eye and adnexa; acid chemical burn of cornea and conjunctival sac), which does not require a fifth digit. This diagnosis is first defined as a burn confined to eye and adnexa (940.x), and the "3" further defines the injury, describing an acid chemical burn of the eye's cornea and conjunctival area.

2. Check that you've coded each burn: Patients who require burn care will often have more than one burn. Check out this quick Q&A, which describes how to code for several multiple-burn scenarios:

Question: What if the patient has burns in different anatomical locations?

Answer: Code separately for each burn, says Jun Mapili, PT, MAEd, rehab therapies supervisor with Global Home Care in Troy, MI. So if the patient has first-degree neck burns and second-degree shoulder burns, you would report the following:

• 943.25 (Burn of upper limb, except wrist and hand; blisters, epidermal loss [second degree]; shoulder) for the second-degree burn

• 941.18 (Burn of face, head, and neck; erythema [first degree]; neck) for the first-degree burn.

When coding for multiple burns, you should list the burn of the highest severity first, Mapili says.

Question: What if the burns are of the same severity and in the same anatomic location?

Answer: You should be able to represent them with a single diagnosis code. Just be sure to use the proper fifth digit to indicate that the burns are in the same area.

For example, if a patient has second-degree burns to her left forearm and elbow, you would code 943.29 (Burn of upper limb, except wrist and hand; blisters, epidermal loss [second degree]; multiple sites of upper limb, except wrist and hand).

Question: What if the patient has burns of varying degrees in the same body area?

Answer: In these scenarios, you'll code only the highest degree burn, says Mapili. So if a patient has first- and second-degree burns on her lower leg, you should report the following:

• 945.24 (Burn of lower limb[s]; blisters, epidermal loss [second degree]; lower leg) for the second-degree burn.

3. Heed "Rule of Nines" for TBSA diagnosis. If the patient has any third-degree burns, the next step is to choose a code from the 948.xx group.

Avoid extra work: Remember, if a patient has no third-degree burns, there is no need to report a 948.xx code in addition to the burn location code.

Explanation: Use the 948.xx (Burns classified according to extent of body surface involved) codes to identify the percent of the body surface burned. Select the fourth digit according to the percentage of total body surface area (TBSA) burned, says Mapili. Then, use the fifth digit to specify the percentage of body surface that has third-degree burns.

To arrive at the TBSA burned, use the "Rule of Nines," which breaks body areas down by percentage of the whole body:

Example: Your patient has a small second-degree burn on her back. She also has a burn covering most of her upper arm, 30 percent of which is a third-degree burn.

Step 1: 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 report 942.24 (Burn of trunk; blisters, epidermal loss [second degree]; back [any part]) to account for both of the patient's burns.

Step 2: Report 948.00 (Burns classified ac-cording to extent of body surface involved; burn [any degree] involving less than 10 percent of body surface; less than 10 percent or unspecified) to indicate the percent of body surface that constitutes the third-degree burn.

Home health coders are often confused about how to code an infected burn, Twombly says. With trauma wounds, the fourth digit generally indicates a complication, she says. But with a burn all five digits are already used to show degree and location, so you need to use a second code, 958.3 (Posttraumatic wound infection, not elsewhere classified) to indicate an infected burn, she advises.

You should sequence this code right after the code for the burn.

Many agencies aren't aware that case mix points for burns have changed under the PPS revisions, Twombly says.

Old way: Prior to the new PPS regulations, any burn coded as primary was a case mix diagnosis if you answered yes to M0440 (Does this patient have a skin lesion or an open wound?). You received 21 points for the burn no matter the degree or location of the burn, but it had to be primary, she says.

New way: As of Jan. 1, only second- and third- degree burns can earn case mix points, Twombly says. And if the degree is unspecified, you receive no case mix points.

Avoid 949.x: ICD-9-CM includes code 949.x (Burn, unspecified), but this code should be a last re-sort. In home care, it's always a subsequent encounter, so somebody has decided the degree and location before admitting the patient to home care, says Twombly. The 949.x code says, "We don't have a clue about this burn," she says. "In home care, we'd unwrap the burn to take a look or call the wound care center to get more information."