- Negative Pressure Wound Therapy Effectively Improves Wound Healing.
- Moisture Plays a Vital Role to Speed Epithelization.
- Instillation Fluid Choice Determined by Multiple Factors.
Treatment of acute and chronic wounds is sometimes challenging. Patients with metabolic syndrome, including insulin resistance, obesity or high blood pressure, and malnutrition may find their bodies are unable to adequately heal without additional help. While it may seem counterintuitive, patient who are obese may also be malnourished, as many times they are gaining weight eating processed, junk food filled with empty calories.
Negative Pressure Wound Therapy Effectively Improves Wound Healing
Negative pressure wound therapy (NPWT) is recognized as an effective treatment option for a variety of problem wounds that have failed to move through normal healing. The process is also known as vacuum-assisted wound closure. Traditionally, an air-sealed dressing is used with a small device that reduces air pressure over the wound area. This gently removes fluid, reduces swelling and smaller studies have shown it can independently reduce the bacterial load in the wound.
In many cases, NPWT is used to facilitate healing in challenging wounds. Researchers have presented data revealing that NPWT is a reliable treatment option against conditions such as diabetic ulcers, gaped wounds, enterocutaneous fistula and hard to heal necrotizing fasciitis. The treatment is safe and a systematic review of the literature finds it can accelerate wound healing in diabetic-related chronic leg wounds.
For hard to heal wounds, NPWT demonstrates the ability to improve healing time and has played a role in healing infected vascular wounds after surgery and treating closed skin flaps without complications.
Moisture Plays a Vital Role to Speed Epithelization
Negative pressure helps remove fluid in the area, yet advances in wound care revealed the vital role moisture plays in healing as it’s a key component to creating an environment that speeds epithelization and accelerates wound healing. Replication and migration of cells requires moisture to generate healthy tissue. When scabs form it can inhibit the replication of epithelial cells and act as a barrier to healing. While scabs in a small, normally healing wound may help protect the open area from bacterial infection, in larger wounds it creates a challenge.
The addition of instillation with NPWT addresses the unique needs of hard to heal wounds and helps reduce the bacterial load and biofilm formation. The combination therapy is NPWTi and effectively helps heal clinically infected wounds, restart wound healing with stalled wounds and reduce wound pain. NPWTi has been successfully used in wounds with infected orthopedic hardware and exposed abdominal wall mesh.
A foam dressing is placed against the wound and covered by a semi-occlusive dressing. A tube is run through the drape to a device that pumps fluid at preset timed intervals where it is held in the foam dressing against the wound. The device then creates negative pressure to pump out the moisture and wound exudate. A multidisciplinary team of experts determined bathing the wound for 10 to 20 minutes, followed by two to four hours of negative pressure may have the best results. Larger wounds may need up to six hours of negative pressure to remove fluid and reduce air pressure.
The process is also sometimes called NPWTi-d with the “d” standing for dwell time of the instillation in the wound area. The therapy is an adjunct to other wound treatments including glycemic control, pressure relief, vascular assessment and systemic antibiotic therapy when necessary.
Instillation Fluid Choice Determined by Multiple Factors
There are two types of fluid used to bathe the wound – saline and antibiotic. Both have demonstrated the ability to improve outcomes. While there is no concrete algorithm to determine the ideal choice, the team can weigh the benefits and disadvantages of each and test the progress.
Admittedly, there is documented overuse of antibiotics, especially in the outpatient population where a mere 13% of those prescribed may be appropriate. This raises the risk of antibiotic resistance, which is endangering the efficacy of antibiotic use. Bacterial infections have once again become a threat decades after the discovery of antibiotics because of antibiotic resistance.
If there is a clear choice to be made in treatment, it is helpful to know that up to 98% of patients in one study who were treated with saline instillation could have the area closed after NPWTi, despite having heavily infected wounds. Additionally, an animal model demonstrated NPWTi with saline resulted in higher quality granulation tissue with more collagen.
There are several variables to consider when using NPWTi, including the wound type, in hospital or outpatient setting, the irrigation solution and the length of therapy. However, NPWT is unquestionably a reliable and effective treatment option for chronic wounds. The combination of negative pressure with instillation raises the success rate and can help accelerate healing, making NPRTi a beneficial and effective option for patients with chronic and hard to heal wounds.