Code for quality of care, not just reimbursement.
According to the Agency for Healthcare Research and Quality (AHRQ), over 2.5 million people in the United States are affected by pressure ulcers each year, with the total annual cost for treatment between $9.1 and $11.6 billion. Pressure ulcers are not just costly; they can cause significant pain, and even death from complications like infections.
Accurate pressure ulcer documentation and coding is essential for improving patient outcomes and ensuring proper reimbursement. This article provides a guide to properly coding pressure ulcers using ICD-10-CM and explains the stages of pressure ulcer severity.
Understand Pressure Ulcer Cause and Presentation
A pressure ulcer, also called a bedsore or decubitus ulcer, is damage to the skin and underlying tissue typically caused by prolonged pressure. Pressure ulcers can develop when a patient spends extended time on their back, side, or stomach due to limited mobility. They are more likely to develop over bony areas like the hips, lower back, buttock, elbows, and heels because blood flow to surrounding tissue is restricted when bone presses against a hard surface, like a bed. The result is a breakdown of the skin and underlying tissue because blood cannot deliver oxygen to the area (hypoxia). A pressure ulcer may become infected or progress deeper into muscle or bone if it is not managed.
Pressure ulcer codes are in the L89.- (Pressure ulcer) category of ICD-10-CM and are classified by site and stage of severity. These stages were revised by the National Pressure Ulcer Advisory Panel (NPUAP) and are based on the depth of tissue damage:
- Stage 1: A persistent red or discolored area that does not turn white when pressed (non-blanchable). The top layer of skin (the epidermis) is intact, and the area may feel warmer or cooler than nearby skin.
- Stage 2: Partial-thickness tissue loss. The ulcer is open and reveals the dermis beneath. The ulcer may look like a fluid-filled blister or a shallow open sore.
- Stage 3: Full-thickness tissue loss. The ulcer affects the deeper layers of the skin and the tissue beneath it (the subcutaneous tissue). It exposes fat, but not muscle, tendon, or bone. There may be undermining (when the wound edges separate from healthy tissue) or tunneling (when a channel extends from the wound).
- Stage 4: Full-thickness tissue loss reaching down to muscle, bone, or supporting structures such as tendons or joints. There may be undermining or tunneling.
- Unstageable: The ulcer is covered by dead tissue (eschar or slough), making it difficult to see how deep it goes. These ulcers are typically understood to be full-thickness tissue loss (stage 3 or stage 4) underneath the eschar or slough.
- Deep tissue pressure injury (DTPI): A persistent area of non-blanchable dark red or purple skin due to damage to deep soft tissue caused by prolonged pressure or shear. The skin may be intact or non-intact and there may be a blood-filled blister. A DTPI may evolve into a stage 3 or stage 4 pressure ulcer.
- Unspecified: The documentation does not specify the stage of the ulcer.
Note: Do not to confuse “unspecified” with “unstageable.” “Unstageable” means the provider could not visualize the extent of the tissue damage, while “unspecified” means the medical record lacks staging information.
Consider These Facets When Coding
The patient’s provider must document the pressure ulcer diagnosis. However, other clinicians can document pressure ulcer stages. Code the location and stage of the ulcer to the highest specificity provided. If there is conflicting information, query the attending provider.
- Coding multiple ulcers: Code each unique pressure ulcer with a code from the L89.- category.
- Example: A patient has two pressure ulcers, a stage 1 pressure ulcer on their sacrum and a stage 2 pressure ulcer on their left elbow. Two codes are assigned: L89.151 (Pressure ulcer of sacral region, stage 1) and L89.022 (Pressure ulcer of left elbow, stage 2).
- Gangrene: Gangrene occurs when tissue dies because of infection or lack of blood supply. Code I96 (Gangrene, not elsewhere classified) first when it is associated with a pressure ulcer.
- Skin infections: Code any skin infections separately using L00-L08 (Infections of the skin and subcutaneous tissue).
- Healing and healed ulcers: If a pressure ulcer is described as “healing,” it should be coded with the stage listed in the documentation (or as unspecified if the stage is not listed). If a pressure ulcer was present on admission and then completely healed during the duration of the patient’s stay, then use one code for the site and stage of the pressure ulcer at admission. If a patient is admitted with a fully healed pressure ulcer, do not code it. If it is not clear whether the patient has a new pressure ulcer or is being treated for a healing ulcer, query the provider.
- Example: A patient is admitted with a pressure ulcer across their back, buttock, and hip of an unspecified stage. By the time the patient was discharged, their ulcer had healed. Code L89.40 (Pressure ulcer of contiguous site of back, buttock and hip, unspecified stage), as it was the stage present at the time of admission.
- Stage changes: Pressure ulcer stages may change during a patient’s stay. If a pressure ulcer is present on admission but progressed to a different stage, two codes are assigned: one for the site and stage on admission and another for the highest stage during the stay. Knowing stage on admission is important; Medicare does not pay for stage 3 and stage 4 pressure ulcers if they were not present on admission.
- Example: A patient is admitted with a stage 1 pressure ulcer on their head. During their stay the ulcer progresses to stage 2. Code L89.811 (Pressure ulcer of head, stage 1) and L89.812 (Pressure ulcer of head, stage 2).
- Debriding unstageable ulcers: Only code for the newly determined stage of an unstageable ulcer if the stage becomes clear following medical treatment that removes the dead tissue covering the ulcer (debridement).
- Example: A patient has a pressure ulcer on their left hip covered by thick eschar. The provider cannot visualize the wound bed, so it is coded as L89.220 (Pressure ulcer of left hip, unstageable). Later, the provider performs a debridement and sees the hip ulcer is stage 3. Code L89.223 (Pressure ulcer of left hip, stage 3) instead of L89.220.
See Coding as a Tool to Preserve Quality of Care
Coding pressure ulcers accurately is important not only for appropriate reimbursement but also for improving patient health. Hospitals can collect data on patients with pressure ulcers to identify high risk patients so the facility can implement protocols to reduce the occurrence of new pressure ulcers. Continuous education and training are needed to manage pressure ulcers effectively and save lives.
Angela Halasey, BS, CPC, CCS, Contributing Writer
