Using a Single VAC Device for Two Separate Wounds
A single NPWT device can be used to treat two separate 2 cm diameter wounds that are 6 cm apart, but this requires bridging the wounds with foam dressing under a single occlusive seal to create one continuous treatment area.
Technical Feasibility and Approach
The standard NPWT system consists of a foam or gauze wound filler, a semi-occlusive barrier dressing, and a fluid collection system that applies negative pressure evenly across the wound surface 1. When treating multiple wounds with one device:
Bridge the wounds by placing foam dressing material between the two separate wounds and covering the entire area (both wounds plus the intervening skin) with a single occlusive adhesive drape 1, 2.
The negative pressure will be distributed across both wound sites simultaneously through the continuous foam interface, allowing treatment of multiple wounds with one vacuum unit 2, 3.
Ensure the intervening intact skin between wounds is protected with a wound contact layer or interface material to prevent maceration or damage from the negative pressure 2, 4.
Practical Considerations
Standard pressure settings of 75-125 mmHg can be used for most applications, with lower pressures (75-80 mmHg) appropriate for vulnerable areas 5, 2.
Dressing changes should occur every 2-3 days, which is standard for NPWT regardless of whether treating single or multiple wounds 5, 4.
The foam bridge technique increases the total surface area under negative pressure, which may increase exudate production and require monitoring of the collection canister 1, 4.
Important Prerequisites
Before applying NPWT to any wounds, particularly if there is concern for infection:
Complete surgical debridement of all necrotic and infected tissue must be performed first, continuing into healthy-looking tissue 6, 5.
NPWT should never be applied to wounds with residual necrotic tissue or uncontrolled infection 6, 5.
After adequate debridement, NPWT can help manage infected wounds by removing exudates, reducing bacterial load, and promoting granulation tissue formation 6, 5.
Cost and Resource Considerations
Using a single device for multiple wounds is more cost-effective than using separate devices for each wound 4.
The bridging technique requires more foam dressing material and a larger occlusive drape, but eliminates the need for a second vacuum unit 1, 4.
Staff workload is reduced compared to conventional dressing changes, even when treating multiple wounds 4.