Disclosure: Dr. Lipman discloses that he has received monetary compensation to conduct the study, write the manuscript, and lecture for the company producing the products discussed from Avery Dennison Medical. This study was fully funded by Avery Dennison Medical.

Patients in institutional settings, such as hospitals and nursing homes, often have or acquire chronic wounds such as those resulting from venous insufficiency and pressure ulcers—these wounds can possess a very offensive odor.¹ The most direct way of avoiding or eliminating wound odor is to prevent or eradicate the infection responsible for it. Topical antibiotics, such as metronidazole gel (0.8 w/v) have proved to be quite effective, but can generate resistant organisms. Further, the action of metronidazole can be sluggish; often several days are needed for any infection to be resolved, and meanwhile the odor is still being generated. Thus, in practice, other methods such as charcoal-based dressings are often used with or without concomitant antibiotic therapy.
Odor absorbing dressings have been marketed in one form or other for many years. During the past decades a number of charcoal based dressings have been introduced into the market. Some of the more current products are Actisorb® Silver (Johnson & Johnson Medical Ltd, Gargrave, UK), CarboFlex® (ConvaTec, Princeton, NJ), Carbonet® (Smith and Nephew Medical Ltd, Hull, UK), and LyoFoam® C (SSL International PLC, Canute Court, Toft Road, Knutsford, Cheshire, UK).
One study² investigated the effectiveness of the various charcoal cloths of odor absorbing dressings in adsorbing n-butyric and valeric acids each at an initial concentration of 0.04% (v/v). These aliphatic acids are two of the most common malodorous organic acids found in wounds. The charcoal based material was placed into a vial containing a dilute mixture of the acids and the residual concentration of acids measured using combination of gas chromatography and mass spectroscopy (GC/MS). The charcoal material from Actisorb Plus and CarboFlex were found most effective, while those from Carbonet and LyoFoam C were found inferior to the other two. A further conclusion from an extension of this study³ was that the presence of wound serum greatly inhibited adsorption of fatty acids. Wound malodor obviously emanates in part from bacterial decomposition of the proteins present in serum, and the inhibition of charcoal odor absorbency by the odor precursor is a drawback to its use.
Clearly, the propensity of charcoal to lose effectiveness in the presence of wound exudates is a serious limitation. Charcoal is also of course black and nonconformable. Neither attribute is optimal for construction of wound dressings, which ideally should be self-adhesive, conformable and able to contact the wound surface. A new series of adhesives has been developed that provide an alternative technology for the adsorption of chronic wound and other odors. The new odor absorbent adhesives can be made into dressings designed to be in direct contact with the wound.
Skin barriers can also be made from these adhesives for the protection of the skin around body openings, especially around stomas, the surgically created openings known as colostomies, ileostomies, and urostomies. These novel skin barriers are able to absorb the odor molecules that are associated with feces and urine and, thus, are potentially able to assist in the control of the odor often associated with stomas.

Methods