By Beth Hawkins Bradley RN, MN, CWON

Finding the key to unlocking a non-healing chronic wound keeps us awake at night. Though we have, as bedside clinicians, learned much about the physiology and biochemistry of chronic wounds over the past decade, wound healing is not an exact science. Negative pressure wound therapy (NPWT) has become standard care for certain chronic wounds. Sometimes, however, wounds treated with this therapy do not progress as readily as we think that they should. This has led us to consider combining other wound care products with NPWT. This article will examine the rationale for using three products in combination with negative pressure.

Enzymatic debriding ointments are frequently combined with negative pressure to hasten the removal of necrotic tissue even as NPWT is applied. When clinicians understand the labeling for both products, they can make an informed decision about this combination. First of all, NPWT is contraindicated in wounds with undebrided eschar. When eschar is debrided, slough frequently remains in the wound base. Slough that obliterates the wound base prevents NPWT from being effective because of two factors: slough clogs foam pores which prevents the distribution of negative pressure and reduces the removal of exudate, and slough prevents contact of the foam in the wound base which prevents microstrain and granulation. Clinicians may apply enzymatic debriders in conjunction with NPWT to hasten the removal of slough. Labeling for these products indicates that the ointment must be in contact at the base of the slough for a period of time in order for the product to be effective in breaking down necrotic collagen tissue. Therefore, when an enzymatic debrider is applied to a wound and NPWT is begun immediately, the impact of the debridement may be greatly reduced. Further, the ointment may clog foam pores, causing the same impact that the slough does. In my opinion, it is usually more cost effective to aggressively remove slough before applying NPWT. If NPWT must be applied, consider using a system that allows for irrigation. The streaming of fluid across the wound will likely remove slough effectively, and will keep foam pores open.

Silver is another product that is frequently combined with NPWT. There is no question of the benefit of silver in reducing wound bioburden. Clinicians should take care to understand the properties and application considerations for the silver product that is used. Most often a silver wound contact layer is chosen to be used in conjunction with NPWT. The benefit of using silver in this form is that the silver is in contact with the wound base. Wound fluid is allowed to move through the mesh freely. Microstrain may be slightly reduced, since the wound contact layer prevents foam from coming in direct contact with the wound base. Using silver wound contact layers is usually less expensive than silver impregnated foam. When using silver in combination with NPWT, remember to use it for a specific length of time and for a specific purpose. Finally, silver can render enzymatic debriders inactive, so combining those products is contraindicated. Avoid using silver impregnated alginates or hydrofibers, as these products will clog foam. If irrigation is used in conjunction with NPWT, silver will likely not be needed.

Honey combined with NPWT has become an intriguing idea to some clinicians. Honey has antibiotic/antimicrobial properties, and increases the osmolarity of the wound environment. These features have led clinicians to combine honey with NPWT to reduce odor associated with the use of NPWT in certain wounds. The increased exudate associated with increased osmolarity may assist with slough removal. Medical honey products can add significant cost to NPWT dressings. Some formulations may impact the effectiveness of NPWT by clogging foam pores and reducing foam interface with the wound base. There is a honey-impregnated wound contact layer available that may reduce the negative impact of a paste or alginate combination honey product. If an NPWT system with irrigation is available, the need for adding honey will likely be eliminated.

In conclusion, there are many other products and therapies that clinicians combine with NPWT to enhance outcomes and decrease healing times. It is important to understand product indications and application guidelines to make sure that their combination with NPWT will be beneficial. The irrigation feature that is available with certain NPWT systems may be very effective in eliminating the need for product combinations.

About the Author
Beth Hawkins Bradley, RN, MN, CWON is the director of Clinical Operations at Cardinal Health. She has been certified in the specialty of Wound, Ostomy, Continence nursing since 1990.

The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.