According to the NCUAP guidelines for staging pressure injuries, the wound in the attached photo would be classified as:

• Stage 2
• Stage 3
• Stage 4
• Unstageable

Answer: C

Stage 4 pressure ulcers are defined as the following: Full thickness skin and tissue loss.  Full-thickness skin and tissue loss with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage or bone in the ulcer.  Slough and/or eschar may be visible.  Epibole (rolled edges), undermining and/or tunneling often occur.  Depth varies by anatomical location.  If slough or eschar obscures the extent of tissue loss this is an Unstageable Pressure Injury.

Category/Stage 4 ulcers can extend into muscle and/or supporting structures (e.g., fascia, tendon, or joint capsule), making osteomyelitis or osteitis likely to occur.  Exposed bone/muscle is visible or directly palpable.[1] 

Several points in the definition of Stage 4 PUs are notable, e.g. variable depth depending on anatomical location.  PUs on the elbow become Stage 4 with very little depth because of the lack of soft tissue between the skin and the fascia.  Not only do they develop into Stage 4 quickly, they undermine and/or tunnel quickly as well, and heal very slowly, again because of the lack of soft tissue available to support granulation.  The lesson here is to PREVENT!!! elbow ulcers with foam pads and bed mobility training to eliminate friction and shear during transfers.

Another point is the occurrence of osteomyelitis, especially in the sacrum.  One of the first times I was debriding a Stage 4 sacral ulcer, I realized the hard chips I was removing was bone.  Then granulation began to develop over the residual sacrum!  How could this be happening?  The inflammation and infection that occurs with osteomyelitis causes the trabecular bone to swell, the cortical bone loses its blood supply and becomes necrotic, thus causing it to chip away.  As the inflammation and infection respond to antibiotics, the trabecular bone granulates.  The healing phases of inflammation and proliferation in bone follow a similar pattern to soft tissue injury, and this is what I was visualizing in my patient.  It was amazing!!!

A treatment plan for a Stage 4 PU includes the same components as for other PUs: remove the necrotic tissue, treat any infection present, reposition as much as necessary for the patient’s individuality, optimize nutrition, and apply moist wound healing principles.  When dealing with wounds of this depth, several adjunct modalities may be useful.

Ultraviolet C for its bactericidal effects.[2]^,[3]

Pulsed lavage with suction to loosen necrotic tissue, remove drainage, and assist with debridement.[4]

Electrical stimulation to reduce the wound surface area through stimulation of granulation synthesis and re-epithelialization (Level 1 evidence).[5]

Negative pressure wound therapy to promote proliferation, reduce wound volume, manage drainage, enable earlier mobilization, protect the wound from environmental contaminants, and reduce the number of dressing changes.  There are several clinical considerations for the use of NPWT on pressure ulcers, especially over the sacrum, including the following:

• The patient’s nutrition status must be sufficient to support tissue synthesis.
• Hypotensive patients may require a lower pressure setting; otherwise superficial capillaries will be compromised and a thin layer of necrotic tissue may form on the wound surface.
• Viable bone, muscle, and tendon need to be covered with petrolatum-impregnated gauze or non-adherent mesh to prevent dessication.
• Periwound tissue may need extra protection to prevent irritation upon removal of the adhesive drape.
• Any time the integrity of the foam is compromised due to fecal or urinary incontinence, the entire dressing must be changed.[6]

Sometimes wound closure for Stage 4 PUs is achieved by a muscle flap performed by a plastic surgeon, in which case successful long-term outcomes depend upon stringent precautions to prevent any shear between the flap and the recipient tissues. 

Close communication among all the medical team members is especially imperative when treating patients with Stage IV PUs in order to achieve the optimal outcomes for the patient.   

[1] Center for Medicare and Medicaid Services.  Medicare Policy Regarding Pressure Reducing Support Surfaces – JA1014.  Available at https://www.cms.gov/Medicare/Medicare-Contracting/ContractorLearningResources/downloads/JA1014.pdf.  Accessed September 8, 2019. 

[2] Yang J, Wu U, Tai H, Sheng W.  Effectiveness of an ultraviolet-C disinfection system for reduction of healthcare-associated pathogens.  Journal of Microbiology, Immunology and Infection.  2019;52(3):487-493.

[3] Haan J, Lucich S.  Ultraviolet C. In Hamm R (Ed), Text and Atlas of Wound Diagnosis and Treatment: 2^nd edition.  New York: McGraw Hill Education.  2019, 511-518.  Available at https://accessphysiotherapy.mhmedical.com/book.aspx?bookid=1334. 

[4] Gibbs KA, Hamm RL. Pulsed lavage with suction. In Hamm R (Ed), Text and Atlas of Wound Diagnosis and Treatment: 2^nd edition.  New York: McGraw Hill Education.  2019, 475-486.  Available at https://accessphysiotherapy.mhmedical.com/book.aspx?bookid=1334. 

[5] Girgis B, Duarte JA.  High voltage monophasic pulsed current (HVMPC) for stage II-IV pressure ulcer healing.  A systematic review and meta-analysis.  Journal of Tissue Viability. 2018;27(4):274-284.

[6] Gibbs KA, Hamm RL.  Negative pressure wound therapy.  In Hamm R (Ed), Text and Atlas of Wound Diagnosis and Treatment: 2^nd edition.  New York: McGraw Hill Education.  2019, 475-435-457.  Available at https://accessphysiotherapy.mhmedical.com/book.aspx?bookid=1334.