Wet-to-Dry Gauze Dressings: Fact and Fiction

Introduction The purpose of this article is to bring to the attention of surgeons some of the literature on wound dressings and the concomitant lack of research base for their practice of utilizing wet-to-dry and gauze dressings. The aims of the research described here were to identify what actually constitutes a wet-to-dry dressing, explain why it is used, and describe how specialist nurses interpret this technique. Review of Current Literature Wet-to-dry and gauze dressings are the most widely used primary dressing material in the United States (US),[1] and there is evidence that they are used inappropriately.[2] Journals and texts in the US support the principle of moist wound healing, but in practice the use of gauze, particularly as a wet-to-dry dressing, does not ensure a moist wound environment.[3] The literature describes wet-to-dry dressings as a means of mechanical debridement,[4–6] although efficacy in removing debris is not indicated. The importance of ensuring damaged and dying tissue is removed from a wound has been demonstrated by several authors[7,8] who advocate sharp debridement. The Agency for Healthcare Research and Quality (AHRQ), formerly the Agency for Health Care Policy and Research (AHCPR), guidelines[4] have promoted the use of wet-to-dry dressing for debridement by stating that use is supported by expert opinion (rated as C on their scale of hierarchy of evidence). Some controversy exists regarding what type of gauze should be used[9] and whether the dressing should be dry or moist when removed.[10,11] The AHRQ4 guidelines only comment on the latter issue, stating that moistening before removal at least partly negates the object of the dressing. The references at this point in the guidelines (page 48) relate to the nonselectivity of the dressing and focus on the pain caused to the patient on removal, not on the efficacy of wet-to-dry dressings. The guidelines clarify that wet-to-dry dressings should not be used as a generally acceptable form of a moist gauze dressing. In taking this approach, AHRQ have essentially supported the use of wet-to-dry dressings for debridement of pressure ulcers and the continuing use of moist gauze for primary dressings. Ovington in a recent article[2] describes gauze as, “still the most widely used wound care dressing and may be erroneously considered a standard of care.”[2] The paper notes that ‘wet-to-dry’ and ‘wet-to-moist’ are often used in practice in a way that makes them indistinguishable. Coupled with the fact that neither are actually used ‘wet’ both the term and the technique start to take on questionable value. Impeded healing due to local tissue cooling, disruption of angiogenesis by dressing removal, and increased infection risk from frequent dressing changes, strike through, and prolonged inflammation are all mentioned by Ovington as good reason to abandon this traditional dressing technique.[2] Ovington also presents a cost-effectiveness argument for change. An illustration is given of costs over a four-week period comparing saline and gauze with an advanced dressing (Tielle®, Johnson & Johnson Wound Management, Somerville, New Jersey) being performed by a home health nurse. The largest contribution to cost is nursing time; even with the patient doing some of his or her own care the cost is reduced with the advanced dressing due to fewer dressing changes and shorter healing time. There are other important considerations when choosing a dressing, such as clinical outcome, quality of life issues, discomfort, disruption of daily routines, and coping with daily activities that can all be addressed by modern products. In a Canadian paper described as a synthesis of the AHRQ guidelines, European guidelines, and current literature,[12] there is no mention of wet-to-dry dressings, though a companion paper in the same journal[13] describes this approach as a simple debridement technique that is nonselective, traumatic, painful, costly, and time consuming. For patients with diabetic foot ulceration, infection is a particular concern. The incidence of infection in foot ulcers of diabetic patients is significantly less in semi-occluded wounds than those dressed with gauze.[14] Despite this, there is still a huge worry for these patients that anaerobic organisms, such as Clostridia sp., would find such an environment too tempting. Using a wet-to-dry dressing to mechanically debride a sloughy, necrotic, chronic wound may be acceptable currently in the US but what of the open postoperative wound where there is no visible dead tissue or debris? Tradition often leads surgeons to prescribe a wet-to-dry gauze dressing for such a wound; all the research done has yet to end this practice, as tradition is a powerful force.15 Methods The design of the study consisted of a descriptive, exploratory mailed questionnaire (of mostly closed items) sent to a convenience sample of 127 out of approximately 190 practicing general surgeons in New Hampshire and Vermont (whose names were obtained from the state medical boards). Nine nurses specializing in wound care, from a variety of areas and work environments, were interviewed as key informants and their views analyzed to assure a US perspective and validate the data.[16] A pilot study (n=5) was conducted and the questionnaire adapted to accommodate suggestions from the doctors and nurses who participated. The questionnaire was designed to discover how many doctors would prescribe four types of gauze dressing, including wet-to-dry, rather than four alternatives (alginates, gels, foams, and hydrocolloids). Eight different types of wounds were presented, and the doctors were asked to choose only one of the dressings listed for each wound in order to build a picture of dressing usage. The second part of the questionnaire investigated the steps involved in the technique of wet-to-dry dressing. Participants were asked to choose between eight different procedures for wet-to-dry dressings. The third part looked at the participants’ reasons not to use the modern products. Results Of the 127 general surgeons, 65 completed and returned the questionnaires, a response rate of 51.2 percent.[17] Graphs representing the results from the first section of the questionnaire are shown in Figures 1 through 3. It can be seen from the graphs that gauze dressings were prescribed much more than alternatives for all the wounds given except venous leg ulcers. Thirty of the 65 respondents chose wet-to-dry dressing for an open surgical wound healing by secondary intention (Figure 2), demonstrating that wet-to-dry dressings are being prescribed inappropriately. The surgical wound was not described as in need of debridement. Moist gauze was chosen by most of the rest of the respondents. Not a single respondent would use any modern dressing product on an excised abscess. Four doctors would use wet-to-dry dressings on a graft site, but the reasons for this are unclear. The frequent use of wet-to-dry gauze for debridement is shown, and this might be viewed by some as an appropriate use of the technique, but it also indicates little use of the less expensive, more comfortable alternatives. Of 65 doctors, 32 selected only gauze products for the wounds given, and only 13 selected three or more alternative dressings. One doctor chose an alternative to gauze dressings for all the wounds except for the pilonidal sinus where he chose wet-to-dry. One doctor chose petrolatum-impregnated gauze for all but the wound needing debridement where wet-to-dry was chosen. How wet-to-dry dressings are performed in practice varies across healthcare professionals. Respondents were asked to select their procedure of choice (Table 1 and Figure 4). Only 49 doctors completed this section fully, so although 40.8 percent agreed with Procedure 5, this is less than a third of all respondents. The part of the procedure with most agreement was that the type of gauze used is important. Forty-one of the 49 who responded took the opportunity to write in the type of gauze they thought should be used. Three chose nonwoven, with the rest opting for large, open-weave, plain gauze with no filler. The debate in the journals regarding nonlinting properties of nonwoven11,18 was not evident in the response. For Procedures 3 and 6 wet-to-dry was a total misnomer, as the gauze is never applied wet and would not have been allowed to dry, although 20 doctors chose these options. Barriers to the use of modern products did not appear to be associated with availability (49 had access to alternatives) or knowledge and experience of use. Cost was the most frequently cited barrier, with only seven surgeons believing alternatives to gauze were cost effective. Cost effectiveness and unit cost are not the same thing. Modern products have a higher unit cost but require fewer changes than gauze, making them more cost effective.[2,19] If other issues, such as time to healing and quality of life, are included, cost effectiveness should be a major force for change. The nurse interviews confirmed that the wet-to-dry dressing technique is interpreted in many different ways, indicating that though the gauze should be allowed to dry out many staff will moisten it to assist removal. Six would use wet-to-dry for debridement, one rarely used the technique, one used ‘moist-to-moist,’ and one used ‘wet-to-dry’ on most wounds. If debridement is not required, then nurses admitted to moistening the gauze prior to removal. Differences between prescription and practice were not viewed by most of the nurses as of any consequence, and most admitted amending an order from wet-to-dry to moist gauze, particularly if there ‘is no visible debris’ in the wound. Discussion There are increased rates of epithelization when wounds are kept moist and occluded.[20–22] The current view is that a moist wound environment is essential to maximize the biological processes required for wound healing.[5,6] The use of modern dressing products does not necessarily ensure a moist environment, as not all are semi-occlusive. However, all are more likely to remain moist if used as recommended. It may be that it is the semi-occlusive nature of some of these dressings that has made doctors resistant to their use, despite research indicating that occlusion does not increase infection rates.[14,23] Why is it that surgeons are not changing practice in line with research findings? Around half of the doctors in the study only used gauze for the wounds given. This has been the traditional postoperative order of the surgeon for so long that the current evidence has not been able to influence those in a position to promote change. Change Management Theory has shown that letting go of tradition is not an easy process, and when the tradition is frequently delegated (to nurses), rather than personally practiced, there may be even less motivation to change. Three quarters of the respondents had access to alternative dressings, and 62 percent indicated experience with their use; over a half of respondents believed that wet-to-dry dressings keep clean open wounds free of debris, indicating that there is still a long way to go in changing fundamental beliefs. As only a third of the surgeons expect wet-to-dry dressings to be initiated moist and removed dry and many specialist nurses know that their nursing colleagues moisten the gauze before removal, this research suggests that there are considerable differences in how the dressing is performed. It supports other authors in the view that wet-to-dry dressings and moist gauze have become synonymous[2,13] and suggests that surgeons need to be aware that a prescription for a wet-to-dry dressing is not as clear as they may think. The introduction of the Prospective Payment System (PPS) in the community may change how doctors prescribe dressings. It will become difficult for agencies to afford time-consuming, twice-daily practices, particularly when there is a limit to the length of time they may continue patient visits. This research demonstrates that the respondents do not currently consider alternatives to gauze as cost effective. The cost effectiveness of modern dressings has been shown,[2,19] and once surgeons see the positive effect of modern dressings on their community patients, they may start looking at these products for their hospital patients. Evaluation and Conclusion Despite the obvious move away from wet-to-dry dressings by the experts, the updates for the AHRQ guidelines still give the impression that experts agree wet-to-dry dressings are a suitable debridement technique to use. The journals are full of articles on modern dressings, but the reality is shown well by the research detailed; surgeons have not been influenced by the developments in wound dressings. They continue to prescribe both wet-to-dry and moist gauze in preference to modern wound care products and often inappropriately. The evidence to minimize the use of moist gauze dressings is available but it is disparate and most nurses are not in a position to influence the practice of surgeons. The questionnaire detailed here shows clearly what is ordered by surgeons, but the results were not able to do more than indicate that it is tradition and issues relating to cost that keeps gauze in wounds. It is likely that the research on alternative dressings is thought by surgeons to be of questionable validity, as much of it is based on small studies. There is a paucity of large-scale, randomized, controlled trials in wound care, and much of the research comes from the UK where wet-to-dry dressings are not performed. The confusion related to the use of ‘wet-to-dry’ interchangeably with ‘moist gauze’ has made researching this paper difficult, but it makes the consistent interpretation of doctors’ orders impossible. Surgeons need to re-address their approach to clean, open surgical wounds and start to look at gauze alternatives in order to minimize wound bed disruption, improve cost effectiveness, reduce the frequency of dressing changes, and increase patient comfort.