What is the recommended treatment approach for a patient with a large or complex wound, potentially complicated by conditions such as diabetes, vascular disease, or previous surgeries, to enhance wound healing rates?

Recommended Treatment Approach for Large or Complex Wounds

For patients with large or complex wounds—including those with diabetes, vascular disease, or previous surgeries—split-thickness skin grafting (STSG) combined with negative pressure wound therapy (NPWT) should be the standard treatment approach, as this combination consistently achieves superior graft take rates (>95%) and faster healing compared to conventional dressing methods.

Treatment Algorithm

Pre-Grafting Phase (Wound Bed Preparation)

• Apply NPWT at -80 mm Hg to the wound bed prior to grafting to optimize the recipient site, particularly when dealing with less-than-ideal conditions common in diabetic or vascular disease patients 1.
• Continue NPWT for approximately 12 days (median duration) until the wound bed demonstrates optimal characteristics 1.
• Monitor for improvement in granulation tissue (target: 90% coverage) and reduction of nonviable tissue (target: 0%) 1.

Grafting and Post-Grafting Phase

• Immediately after STSG application, apply NPWT at -80 mm Hg directly over the graft as a bolster dressing rather than using conventional tie-over dressings 2, 1.
• Maintain continuous negative pressure for 4-5 days post-grafting 3, 2.
• This approach is particularly effective for diabetic foot wounds, where studies demonstrate average healing times of 17 days for wounds averaging 57 cm² 4.

Evidence Supporting This Approach

Superior Graft Take Rates

The most compelling evidence comes from a 2011 randomized controlled trial in burn patients, which demonstrated:

• NPWT achieved 96.7% average graft take versus 87.5% with conventional dressing (statistically significant, p<0.001) 2.
• Graft take ranged from 90-100% with NPWT compared to 70-100% with conventional methods 2.
• In the postgraft setting specifically, median graft take of 96% was observed at 5 days 1.

Faster Healing Times

• Mean time to complete healing was 5.8 days with NPWT versus 8.9 days with conventional dressing (p<0.05) 3.
• Duration of continued dressings averaged 8 days with NPWT versus 11 days with conventional methods (p<0.001) 2.
• For diabetic foot wounds specifically, average healing time was 17 days for large wounds (mean 57 cm²) 4.

Special Population Considerations

For diabetic patients: The combination is particularly powerful, as demonstrated in a 2020 retrospective review showing consistent improved outcomes in diabetic foot wounds resulting from severe soft tissue infections 4. The mean follow-up of 13 months demonstrated durability of results 4.

For peripheral arterial disease (PAD) patients: Case reports demonstrate 100% STSG uptake even in this challenging population when disposable NPWT systems are used 5.

Technical Considerations

NPWT Material Selection

• Both foam-based and gauze-based NPWT are effective, though gauze-based systems offer advantages in complicated wound geometries and are easier to apply 1.
• Disposable, ultraportable NPWT systems provide a more cost-effective and comfortable patient experience while maintaining efficacy 5.

Pressure Settings

• Standard pressure of -80 mm Hg should be used for both pre-grafting wound bed preparation and post-grafting bolster application 2, 1.

Duration of Therapy

• Pre-grafting: Continue until wound bed optimization (approximately 12 days median) 1.
• Post-grafting: Maintain for 4-5 days to ensure graft adherence and microcirculation establishment 3, 2.

Mechanism of Benefit

The synergistic effect works through multiple pathways:

• Improved microcirculation between the graft and recipient bed 3.
• Tight adhesion preventing fluid accumulation and shear forces 3.
• Reduction of nonviable tissue and promotion of granulation tissue in the wound bed 1.
• Elimination of dead space and continuous drainage of exudate 2.

Common Pitfalls to Avoid

• Do not use conventional tie-over dressings when NPWT is available, as this requires more frequent dressing changes (average 3.2 dressings), longer healing times, and greater restriction to the graft site 3.
• Do not remove NPWT prematurely—maintain for the full 4-5 day period post-grafting to maximize graft take 3, 2.
• Do not assume NPWT is cost-prohibitive—the therapy can be effectively assembled using locally available materials, and reduced dressing frequency offsets initial costs 2.

Composite Grafting Option

For wounds requiring enhanced dermal thickness to prevent contracture:

• Consider 1-stage allodermis combined with STSG under NPWT, which achieved 97.8% graft take at day 5 and complete healing in 5.8 days 3.
• This provides functional and aesthetic results mimicking full-thickness grafts without requiring large full-thickness donor sites 3.