Some wounds need more than a dressing. They need active mechanical support to manage fluid, reduce swelling, and create the conditions for tissue growth. Negative pressure wound therapy (NPWT), commonly called wound VAC therapy, provides that support through controlled suction applied directly to the wound bed.
NPWT has become one of the most widely used advanced wound therapies in clinical practice because it addresses multiple healing barriers simultaneously. At Wound Care Specialists, we use NPWT as part of an integrated treatment plan, selecting the system, pressure settings, and foam type based on the specific needs of your wound.
The Process
NPWT works by placing a specialized foam or gauze dressing into the wound, sealing it with an adhesive drape, and connecting it to a pump that applies subatmospheric (negative) pressure. That controlled suction produces several therapeutic effects:
The suction physically contracts the wound edges, pulling them closer together and reducing the overall wound volume. This also helps remove excess fluid and decrease swelling in the surrounding tissue.
At the cellular level, the suction stretches fibroblasts (the cells that build new tissue). This mechanical stretch stimulates them to produce vascular endothelial growth factor (VEGF), which promotes new blood vessel formation, and accelerates the production of granulation tissue.
By continuously removing wound exudate, NPWT decreases the concentration of destructive enzymes (matrix metalloproteinases) that break down new tissue. It also removes bacteria-laden fluid, reducing the wound's bioburden.
Pressure settings typically range from negative 75 to negative 125 mmHg, with higher pressures (up to negative 150 mmHg) used for wounds with heavy drainage. Treatment usually begins with continuous suction for the first 48 to 72 hours, then transitions to intermittent cycling, which research suggests may further stimulate tissue growth.
Foam selection also matters. Black polyurethane foam is used to promote granulation tissue in most wounds. White polyvinyl alcohol (PVA) foam is chosen when the wound involves exposed tendons, bone, or other structures that require a gentler, less adherent interface.
For heavily contaminated or undermined wounds, we may use NPWT with instillation and dwell time (NPWTi-d), a variant that delivers antiseptic solution into the wound, allows it to dwell for 5 to 15 minutes, and then removes it via suction. This cycle repeats every two to four hours and is particularly effective for managing complex infections.
Who It Helps
NPWT is effective for a range of wound types, including large or deep chronic wounds, surgical wounds that have opened (dehisced), wounds with heavy drainage, traumatic wounds, and wounds being prepared for surgical closure or skin grafting.
It is commonly used in diabetic foot ulcers, pressure injuries (Stage III and IV), open abdominal wounds, and post-surgical wound complications.
NPWT is not appropriate for all wounds. It is contraindicated in wounds with exposed blood vessels, untreated necrotic tissue, active malignancy at the wound site, uncontrolled bleeding, or untreated osteomyelitis. Your wound care team evaluates these factors before recommending NPWT and monitors the wound closely throughout treatment.
Your Visit
Here's what NPWT treatment typically involves.
NPWT setup is performed in our clinic. Your clinician places the appropriate foam dressing into the wound, applies the adhesive seal, and connects the tubing to a portable or stationary pump. The initial setup takes approximately 30 to 45 minutes.
Many patients continue NPWT at home or in their care facility between clinic visits. Portable systems are lightweight and battery-powered, allowing you to move freely during treatment. You'll receive training on how to manage the device, empty the collection canister, and recognize signs that require a call to our office.
Dressing changes are typically performed two to three times per week, either in clinic or by a trained home health nurse. At each dressing change, we assess the wound's progress and adjust pressure settings, foam type, or the overall treatment plan as needed.
The decision to transition off NPWT is driven by the wound's healing phase and response to therapy. Once the wound has developed adequate granulation tissue and drainage has decreased to manageable levels, we move to the next stage of your treatment plan.
Most patients describe the sensation as mild pulling or tightness when the suction is active. Discomfort is typically manageable and often decreases after the first day. If pain is significant, your clinician can adjust the pressure settings or modify the dressing technique.
Yes. Portable NPWT systems are designed for mobility. Patients can walk, sit, and perform daily activities while wearing the device. The pump is compact and can be carried in a small bag or clipped to clothing.
Treatment duration varies by wound type and response. Some wounds require NPWT for two to three weeks; others benefit from several weeks of therapy. Your clinician reassesses the wound at every dressing change and discontinues NPWT when the wound is ready for the next phase of care.
Most insurance plans, including Medicare, cover NPWT for qualifying wound types. Our team handles authorization and works with your insurance to confirm coverage before beginning treatment.
Standard NPWT applies continuous or intermittent suction. NPWTi-d adds a step: it instills an antiseptic solution into the wound, lets it sit for several minutes, and then removes it via suction. This variant is used for wounds with significant contamination or tunneling where standard NPWT alone may not adequately manage infection.
Request a consultation to find out whether negative pressure wound therapy is appropriate for your wound.