How it Works

Since its introduction, V.A.C.® Therapy has changed the way wounds are healed*. V.A.C.® Therapy promotes wound healing through Negative Pressure Wound Therapy (NPWT). By delivering negative pressure (a vacuum) at the wound site through a patented dressing, the wound edges are drawn together, infectious materials are removed and granulation tissue is promoted at the cellular level. The Vacuum Assisted Closure® (V.A.C.®) Therapy System can help heal most wound types including:

• Degloving
• Severe abscess
• Traumatic wounds
• Infected lacerations

• Chronic wounds
• Incisions with risk of dehiscence of infection
• Ulcers
• Flaps and grafts

Understanding the Science of V.A.C.® Therapy

Proven therapy with over 615 peer-reviewed articles, the clinical and economic benefits of V.A.C.® (Vacuum Assisted Closure®) Therapy, also known as NPWT (Negative Pressure Wound Therapy) are widely known. However, it is equally important to understand how V.A.C.® Therapy works deep inside the wound to achieve these outcomes. The following sections describe how NPWT (Negative Pressure Wound Therapy), namely V.A.C.® Therapy, promotes wound healing and how its unique mechanisms of action differentiate it from other NPWT devices.

• What Makes Up the V.A.C.® Therapy System
• How V.A.C.® Therapy Promotes Granulation Tissue Formation
• How V.A.C.® Therapy Removes Barriers to Healing

What Makes Up the V.A.C.® Therapy System

Three Critical Components, One Unique System

The V.A.C.® Therapy System is comprised of three essential components that actively work together to help promote wound healing through granulation tissue formation.

1. V.A.C.® Therapy Unit Provides intermittent and continuous therapy with integrated patient safety features
2. T.R.A.C.™ Technology Regulates pressure at the wound site to provide accurate delivery of prescribed therapy settings
3. V.A.C.® GranuFoam™ Dressing Help provide the necessary mechanisms to promote granulation tissue formation

How V.A.C.® Therapy Promotes Granulation Tissue Formation

The Science Behind the System: Macrostrain and Microstrain

Under negative pressure, V.A.C.® Therapy with proprietary V.A.C.® GranuFoam™ Dressing applies mechanical forces to the wound to create an environment that promotes wound healing. These forces are known as macrostrain and microstrain.

Macrostrain is the visible change that occurs when negative pressure contracts the foam.

Macrostrain:

• Draws wound edges together
• Provides direct and complete wound bed contact
• Evenly distributes negative pressure
• Removes exudate and infectious materials
• Reduces edema

Microstrain is the microdeformation at the cellular level, which leads to cell stretch.

Microstrain:

• Promotes perfusion
• Promotes granulation tissue formation by facilitating cell migration and proliferation

Using V.A.C.® Therapy with V.A.C.® GranuFoam™ Dressing results in both macrostrain and microstrain for advanced wound healing.

How V.A.C.® Therapy Removes Barriers to Healing

V.A.C.® Therapy Mechanisms of Action

V.A.C.® Therapy creates an environment that promotes wound healing through the following mechanisms:

Wound Healing Barrier	V.A.C.® Therapy Mechanism
Excess bacterial burden	Removes infectious materials
Inadequate protection against infection	Provides protected wound healing environment
Excess exudate	Removes exudate
Excess edema (interstitial fluid)	Reduces edema (interstitial fluid)
Absence of moisture	Provides a moist wound healing environment
Lack of adequate blood flow	Promotes perfusion
Lack of granulation tissue formation	Promotes granulation tissue formation and draws wound edges together

T.R.A.C.™ Technology

V.A.C.® Therapy uses T.R.A.C.™ (Therapeutic Regulated Accurate Care) to:

• Monitor and maintain target pressure at the wound site for consistent therapy delivery
• Helps reduce tubing blocks and false alarms through enhanced fluid dynamics
• Provides alarms for enhanced patient safety

Bibliography

Chen, C. M. (1997). Geometric control of cell life and death. Science , 276, 1425-1428.

Sui Huang, C. S. (1998). Control of Cyclin D1, p27Kip1, and Cell Cycle Progression in Human Capillary Endothelial Cells by Cell Shape and Cytoskeletal Tension . Molecular Biology of the Cell, 9 (11), 3179-319.

Joseph E, H. C. (2000). A prospective randomized trial of vacuum-assisted closure versus standard therapy of chronic non-healing wounds. Wounds, 12, 60-67.

Saxena, V. S., Hwang, C.-W. M., Huang, S. M., Eichbaum, Q. M., Ingber, D. M., & Orgill, D. P. (2004). Vacuum-Assisted Closure: Microdeformations of Wounds and Cell Proliferation. Plastic and Reconstructive Surgery: , 114 (5), 1086-1096.