From the Guidelines
Vacuum-assisted closure (VAC) therapy should be considered as an adjunct therapy to standard of care for the healing of postsurgical diabetes-related foot wounds, as recommended by the International Working Group on the Diabetic Foot (IWGDF) 2023 update 1.
Key Considerations for VAC Therapy
- The wound should be thoroughly debrided of necrotic tissue before VAC application.
- The therapy involves placing a foam dressing in the wound cavity, covering it with an adhesive drape to create an airtight seal, and connecting it to a vacuum pump that applies negative pressure between 75-125 mmHg continuously or intermittently.
- Standard protocol involves changing the dressing every 48-72 hours.
- VAC therapy is contraindicated for malignant wounds, untreated osteomyelitis, non-enteric and unexplored fistulas, necrotic tissue with eschar, and when placed directly over exposed blood vessels, organs, nerves, or anastomotic sites.
Monitoring and Discontinuation
- Patients should be monitored for signs of infection, bleeding, or pain during treatment.
- VAC therapy should be discontinued when the wound bed shows adequate granulation tissue or when the treatment goals are achieved.
Evidence-Based Recommendations
The IWGDF 2023 update provides a conditional recommendation with low-quality evidence for the use of negative pressure wound therapy (NPWT) as an adjunct therapy to standard of care for the healing of postsurgical diabetes-related foot wounds 1. This recommendation is based on the available evidence, which suggests that NPWT may promote wound healing and reduce the risk of complications. However, the quality of evidence is limited, and further research is needed to confirm the effectiveness and cost-effectiveness of NPWT in this context.
From the Research
Guidelines for Using Vacuum-Assisted Closure (VAC) Therapy
- VAC therapy is a closed system that applies negative pressure to the wound tissues, promoting wound blood flow and proliferation of healing granulation tissue 2.
- The method involves removal of excess tissue fluid from the extravascular space, lowering capillary after-load and promoting microcirculation during the early stages of inflammation 2.
- VAC therapy is indicated for various wound applications, including traumatic wounds, infection, fasciotomy wounds, and as a dressing for anchoring an applied split-thickness skin graft 2.
Application and Mechanism of Action
- The technique involves thorough debridement, adequate hemostasis, and application of sterile foam dressing, with a fenestrated tube embedded in the foam and connected to a vacuum pump 3.
- Negative pressure therapy stabilizes the wound environment, reduces wound edema and bacterial load, improves tissue perfusion, and stimulates granulation tissue and angiogenesis 3.
- VAC therapy promotes perfusion, reduces edema, draws the wound edges together, and stimulates the formation of granulation tissue 4.
Nursing Implications and Contraindications
- VAC therapy has proven cost-efficient, safe, and effective as a treatment modality in wound care, but requires careful patient selection and monitoring 5.
- Contraindications include patients with an allergy to any of the components that contact the skin, patients with thin and easily damaged skin, and patients who are fully anticoagulated or have large wound surface areas 2.
- Potential complications and contraindications of VAC therapy include localized superficial skin irritation, and the need for careful monitoring of electrolytes, hematocrit, and fluid balance in certain patients 2, 6.
Benefits and Outcomes
- VAC therapy appears to be a simple and more effective than conventional dressings for the management of difficult wounds, reducing wound volume, depth, treatment duration, and cost 3.
- Benefits of VAC therapy include removal of fluid from the extravascular space, improved circulation, enhanced granulation tissue formation, increased bacterial clearance, and hastening of wound closure 6.