571 NPWT

“Minus™ Negative Pressure Wound Therapy System:

An “ Effective” Device Offering Better Results

  • Creating a Sub-atmospheric Pressure with Vacuum Source
  • Maintaining Wound Temperature and Moisture

Mechanism of Action

Negative pressure interacts with the wound environment on different levels. It acts on both the macrostructure and the microstructure of the lesion and integrates all these effects into one complex activity that promotes wound healing in all phases of wound development. At the macro level, NPWT removes secretions and fluids from the lesion, reduces periwound edema, increases local blood flow, and reduces ulcer size and the risk of wound contamination from external sources. At the micro level, the stimulation that the negative pressure exerts on the cell surfaces and on many of the cellular elements present in the lesion (in parallel with a change in nuclear transcription activity) induces positive changes in both the shape and function of the cells. NPWT has been shown to promote angiogenesis, fibrogenesis and the activity of macrophages and leukocytes. A number of NPWT studies have been performed in virtually all clinical conditions related to wounds and wound management, acute and chronic, from heart surgery to diabetic feet and venous leg ulcers to pressure ulcers. Its activity has been confirmed for most of the conditions under which it has been tested. An interesting option with NPWT is that it can be incorporated into an antiseptic application. This occurs when antiseptics have entered the system to regularly flush wound areas (as was the case with osteomyelitis) or when they are absorbed into the material used to fill the lesion. This adds an antimicrobial effect to the indirect debridement of NPWT, as the newer antiseptics have a better efficacy and safety profile and have been tested successfully under a range of conditions.

1) Creating a Sub-atmospheric Pressure with Vacuum Source

The film has an opening to which a tube is attached. The tube leads to a vacuum pump and a canister in which liquids are collected. The modes of the vacuum pump can be set to run intermittently or to start and stop. The vacuum pump draws fluid and infection out of the wound. This will help bring the edges of the wound together. It also helps the wound to heal by encouraging new tissue growth. Antibiotics and saline solution can be introduced into the wound if necessary.

2) Maintaining Wound Temperature and Moisture

When the temperature drops, the healing stops. In addition, the cooled tissues cause vasoconstriction and increase the oxygen demand of hemoglobin. As a result, the type of white blood cells called neutrophils have less oxygen available to fight off possible infections. After the wound tissue has cooled - for example, if it stays in the air during a dressing change - it can take up to 4 hours for the wound base to return to its normal healing temperature. If a doctor changes a TID dressing, the wound may be outside of the optimal healing range 50% of the time. The negative pressure wound therapy system Minus ™ offers the wound bed a thermally conditioned, oxygen-rich solution at certain intervals. If the temperature is kept at an optimal healing level at 38° C, the temperature loss will be eliminated. In addition, the solution not only helps to wash and dwell the wound bed at the target temperature to penetrate dead corners of the wound edges, but also to retain moisture without macerating the perimeter of the tissue.


MINUS™ Negative Pressure Wound Therapy System is a non-pharmacological method for the patients who would benefit from a suction device. It is intended to use to physically promote wound healing by means of removal of fluids, including irrigation, and body fluids wound exudates and infectious materials. The patients with the following wounds are indicated: Acute Wounds, Chronic Wounds Pressure Ulcers, Diabetic Foot Ulcers, Venous Leg ulcers, Traumatic wounds, Dehisced wounds, Partial thickness burns, Flaps, and grafts. No Studies are done on the use of Minus™ NPWT System on pregnant and pediatric patients. To use the device on such patients is at surgeons’ own disposal. Patient size and age should be considered when prescribing the device. The Minus™ Negative Pressure Wound Therapy System is intended for use in acute and chronic wounds at continual, intermittent and variable mode of settings.