Accessibility Help | Sitemap | Contact Us | Customer Support CALL 1-800-275-4524
United States Change Country
Careers | Investor Relations | News & Media | Events | KCI Recycling | About KCI
Home  |  Conditions  |  Products  |  Clinical Evidence  |  Education and Training  |  For Patients  |  Customer Support  |  Suppliers
You are here: Home > Products > Negative Pressure Technology Platform > V.A.C.® Therapy > Science Behind Wound Therapy

Science Behind Wound Therapy

Understanding the Science of V.A.C. Therapy

Proven therapy with over 918 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

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. SensaT.R.A.C.™ Technology Regulates pressure at the wound site to provide accurate delivery of prescribed therapy settings
  3. V.A.C. GranuFoam™ Dressings Help provide the necessary mechanisms to promote granulation tissue formation

How V.A.C. Therapy Promotes Wound Healing

The Science Behind the System: Macrostrain and Microstrain

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

V.A.C. Therapy and Macrostrain | KCI

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


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

V.A.C. Therapy and Microstrain | KCI

Microstrain is the microdeformation at the cellular level, which leads to cell stretch.1


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

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

Watch a video of how V.A.C. Therapy works through macrostrain and microstrain.


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 Removes barriers to cell migration and proliferation

What is SensaT.R.A.C. Technology?

SensaT.R.A.C. Technology

V.A.C. Therapy uses SensaT.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
  • Enhance patient comfort

For more information on how the patented SensaT.R.A.C. ensures the prescribed negative pressure is maintained for optimal healing outcomes, click here.

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.

  • KCI Express
  • Share on
  • Share on Twitter
  • Visit our YouTube page

Important Message for Patients

Terms of Use | Privacy Notice | Safe Harbor Policy | Contact Us | News Feed

Copyright © 1998 - 2013 KCI Licensing, Inc. All Rights Reserved.    DSL# 09-03-193
The information included in this Web site has been prepared for and is intended for viewing exclusively within the United States of America. This Web site contains information about products which may or may not be available in different countries and if applicable, may or may not have received approval or market clearance by a governmental regulatory body for different indications for use. Please consult individual country sites for approved uses and any applicable restrictions.