Transparent Membrane Dressings: a Q&A
Because Dr. Dennis Makis interview in this issue of ICT mentions transparent polyurethane film dressings, and the Centers for Disease Control and Prevention (CDC) guidelines respecting their use, ICT thought it would be timely to offer answers to some of your frequently asked questions on the topic.
Q: What does the CDC require with respect to exit site dressings for both PIVs and CVCs?
A: The 2002 guidelines state: Use either sterile gauze or sterile, transparent, semi-permeable dressing to cover the catheter insertion site (146,210-212) Category IA. With regard to PIVs, if tape and gauze is used, the CDC requires that you remove the dressing and visually inspect the catheter at least daily and apply a new dressing. Whereas, if a transparent membrane dressing is used, the dressing need only be removed or replaced when the catheter is removed or replaced, or when the dressing becomes damp, loosened, or soiled. The CDC further recommends that all dressings be changed more frequently in diaphoretic patients. As to CVCs, including PICCs and hemodialysis catheters, tape and gauze must be replaced every two days and whenever inspection of the site is necessary. Transparent membrane dressings, on the other hand, may remain in place seven days; replaced more frequently only if the dressing becomes damp, loosened or soiled, or if the catheter is removed.
Q: Given that the guidelines allow for either tape and gauze operating room (OR) transparent membrane dressings, is there any clinical evidence published since the guidelines were issued to suggest one kind of dressing is superior to another?
A: No, there are no new studies that offer a compelling reason to prefer one kind of dressing over another. But lets take a moment to review some of the data that influenced the CDC guideline committee. It is interesting to note that when compared with tape and gauze, there are several studies that demonstrate statistically significant higher skin colonization under transparent membrane dressings.1-3 However, in these same studies, it is important to note that catheter-related bloodstream infections (CRBSIs) did not differ significantly between the groups. The differences in skin colonization between gauze and tape and transparent dressings can be expected due to differences in prepping frequency (two days vs. five days, respectively). Nevertheless, the researchers invariably concluded that transparent dressings are SAFE to use on non-cuffed CVCs, Hickman catheters (in renal transplant patients), and pulmonary artery catheters. Other studies affirm the safety of transparent dressings for other vascular access devices, and these are referenced in the CDC guidelines. Given these clinically proven results, you should consider the aforementioned dressing change regimens, as recommended by CDC, when considering your exit site dressing.
Also, you should know that Dr. Dennis Maki recommends transparent membrane dressings NOT be used on diaphoretic patients, burn patients and on patients with desquamating skin (INS Fall conference, Indian Wells, Calif. 2004).
Q: Are there any other times we should not use transparent membrane dressings?
A: Avoid their use on patients with known tape or adhesive allergy.
Q: We use a variety of agents on the skin, for different reasons skin prep, chlorhexidine, benzoin, etc. Are there any of these we should avoid with transparent membrane dressings?
A: Some caution must be exercised with all skin preps when used under a transparent dressing; namely, you need to be absolutely sure the prep solution is dry before applying the overlying dressing. Failure to take this precaution can result in contact dermatitis. Further, while iodines and CHG have been used safely for years under transparent dressings, at least one manufacturer (3M) recommends avoiding benzoin since it is a skin irritant.
Q: A lot of talk goes on about moisture vapor transmission rate (MVTR) of transparent polyurethane film dressings. One product, OpSite 3000, has a greater ability to transmit water vapor in laboratory tests than another product. Does this have any clinical relevance?
A: Actually, while these differences in MVTR are noted in laboratory tests, clinical outcome testing has proven that there is no clinical difference between transparent membrane dressings with respect to infection. As Maki recently remarked: All transparent membrane dressings show no significant clinical difference in performance and are safe when used in accordance with the guidelines.
- Maki, Stolz, Wheeler, Mermel. A prospective, randomized trial of gauze and two polyurethane dressings for site care of pulmonary artery catheters: Implications for catheter management. Critical Care Medicine, Vol. 22, No. 11, 1994.
- Maki, Will. Abstract published at Surgical Infection Society, Montreal, April 1984, Association for Practitioners in Infection Control, Washington, D.C. June 1984.
- Maki, Mermel, Martin, Berry. Abstract published: The 36th Interscience Conference on Antimicrobial Agents and Chemotherapy, New Orleans, September 1996 and SHEA, 1997.