How should an infected pressure ulcer in an adult be managed, including antimicrobial therapy, surgical debridement, and pressure off‑loading?

Management of Infected Pressure Ulcers

For infected pressure ulcers, initiate systemic antimicrobial therapy only when there is evidence of spreading cellulitis, bacteremia, or osteomyelitis—not for colonization alone—combined with surgical debridement of all necrotic tissue and bone, pressure off-loading with specialized support surfaces, and protein supplementation to promote healing. 1, 2

Antimicrobial Therapy: When and How

Indications for Systemic Antibiotics

Systemic antimicrobials should be reserved for serious infections only 1:

• Spreading cellulitis beyond the ulcer margin
• Bacteremia/sepsis
• Osteomyelitis
• Systemic signs: fever, leukocytosis, bandemia 3

Critical pitfall: Do not treat colonization or positive wound cultures without clinical infection—all pressure ulcers are colonized with bacteria, but this does not require antibiotics 1.

Obtaining Appropriate Cultures

• Superficial wound swabs are unreliable with low sensitivity and specificity 2
• Deep tissue or bone biopsy is essential for directing antimicrobial therapy 1, 4
• Expect polymicrobial infection (87% of cases) commonly involving S. aureus (47%), Enterobacteriaceae (44%), Enterococci, and anaerobes (44%) 5, 2

Duration of Antimicrobial Therapy

• Mean treatment duration: 54 days for osteomyelitis cases 2
• However, prolonged antimicrobial courses do not improve outcomes 2
• Tailor duration to clinical response rather than arbitrary extended courses
• Be aware that extended therapy increases risk of ESBL organisms (associated with fluoroquinolone use) and superinfection with coagulase-negative staphylococci and Candida 5

Surgical Debridement

Surgical debridement is necessary before further treatment and should remove all nonviable tissue, scarred tissue, and infected bone 4, 3.

Debridement Protocol

The evidence supports a two-stage surgical approach 5:

1. Initial aggressive debridement to remove all necrotic tissue and infected bone
2. Negative pressure wound therapy (NPT) for 5-10 weeks (median 7 weeks) 5
3. Flap coverage/reconstruction after infection resolution

Important consideration: Shorter debridement-to-reconstruction intervals are preferable to limit total treatment duration and antibiotic exposure, as the interval length does not correlate with outcome 5.

Osteomyelitis Evaluation

For Stage IV (full-thickness) pressure ulcers, always rule out osteomyelitis 3:

• Clinical examination underestimates deep tissue involvement 1
• MRI or bone scan for radiographic evaluation 4
• Bone biopsy with histopathology remains the gold standard 1, 4
• Osteomyelitis affects up to 32% of full-thickness pressure ulcers 4

Pressure Off-Loading

Pressure relief is fundamental and non-negotiable—without it, no wound will heal regardless of other interventions 6, 7.

Specific Measures

• Use specialized pressure-relieving devices (mattresses, cushions) 3, 6
• Implement repositioning protocols for immobile patients
• Address the underlying cause: if friction/moisture for Stage II ulcers; pressure/shearing forces for Stage III-IV 3

Nutritional Support

Provide protein or amino acid supplementation to reduce wound size 8. This is particularly important as:

• Hypoalbuminemia is associated with pressure ulcer development 3
• Low albumin (<25 g/L) and hemoglobin (<111 g/L) are associated with non-healing ulcers 2

Wound Dressings

Use hydrocolloid or foam dressings to reduce wound size 8. Proper occlusive dressings:

• Increase patient comfort
• Enhance healing
• Decrease infection risk
• Save time and reduce costs 3

Adjunctive Therapies

Consider electrical stimulation as adjunctive therapy to accelerate wound healing (moderate-quality evidence) 8.

Negative pressure wound therapy is widely used in the two-stage surgical approach and weakly recommended 9.

Risk Factors for Treatment Failure

Be aware that 71% of patients experience treatment failure requiring additional surgery or IV antimicrobials 2. Risk factors include:

• Lack of formal care support on discharge (critical modifiable factor) 2
• Previous pressure ulcer history 5
• Post-traumatic neurological deficit 2
• High CRP (>184 mg/L) 2
• Actinomyces infection 5
• Lack of attempted soft tissue coverage 2

One-year mortality is 23%, emphasizing the serious nature of this condition 2.

Key Clinical Pitfalls to Avoid

1. Do not rely on superficial swabs—they are misleading and will result in inappropriate antibiotic selection 2
2. Do not treat colonization—only treat documented infection with systemic signs 1, 3
3. Do not delay surgical debridement—it is essential before other interventions 4, 3
4. Do not use excessively prolonged antibiotics—they don't improve outcomes and increase resistance 2
5. Do not forget discharge planning—lack of care support is strongly associated with failure 2