5.2.4 Pressure sore

Pressure ulcer, decubitus, decubital ulcer.

Prevalence: 10% of hospitalized patients (23% in hospitals in Europe) and 5% of patients requiring nursing care.

Ischaemia caused by prolonged pressure (>72 mm Hg) over bony prominences in patients who are unable to move and naturally avoid pressure. Two hours of ischaemia are sufficient to induce a pressure sore. Risk factors: bed-ridden patient, cachexia, paraplegia, unconsciousness, anesthaesia, shock, diabetes mellitus, anaemia. Since the musculature is even more sensitive to pressure than the skin and subcutis, cavitating wounds extending from below the skin to the periosteum may evolve.

Initial livid or bruise-like colour changes over the pressure points, reduced capillary refill. This stage is reversible. Later ulcers develop, involving skin, subcutis, muscles and often extending to the bones. Expanding cavitating defect, which is larger at its base. Foetid odour.

Stage I: Livid erythema (macule or patch), some capillary refill.

Stage II: Ulcer to dermis.

Stage III: Ulcer with full thickness skin loss to subcutaneous fat.

Stage IV: Ulcer with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage or bone.

Additional PI definitions: Medical device–related PI.

Inflammatory markers, reduced serum albumin. Imaging studies, possibly nutritional evaluation.

Biopsies of the ulcer margin (and possibly ulcer base) should be taken after 8 to 12 weeks of ulcers without tendency to heal, primarily to rule out tumors, vasculitis and other causes. Biopsy should be taken especially before invasive measures.

Neuropathic pressure ulcer, ulcerated tumours, chronic infections with fistula formation (for example, infected hip prosthesis).

Follow the International Guideline Prevention and Treatment of Pressure Ulcers/Injuries (see references below).

Prevention is most important: Bed-ridden weak patients who cannot move adequately should be turned or shifted every two hours. Pillows should be employed to place patients in a 30° lateral position, as this simultaneously relieves pressure over the sacrum and trochanters. Offload heels with a prophylactic dressing or a pillow, without placing pressure on the Achilles tendon. Use textiles with low friction coefficients and consider specific single layer foam mattress or an alternating pressure air mattress or overlay. Optimize energy intake.

In stage I, the tissue damage is reversible. Immediate institution of pressure-relieving measures. Protection of damaged skin (e.g. hydrocolloid dressings). In stage II superficial tissue damage has occurred. Debridement of necrotic tissue and standard moist wound therapy. Appropriate antibiotic coverage.

In stages III and IV the actual extent of the tissue damage is often underestimated. Two hours of ischaemia are sufficient to induce a pressure sore. Extensive debridement, resection of the overhanging wound edges, vacuum-assisted wound therapy until adequate granulation is induced, then standard moist wound therapy. Pressure sores in stage III and IV often require reconstructive surgery.

Consider the potential impact of impaired nutritional status, critical care stay, presence of medical devices and the impact of increased body temperature on pressure injury risk.