Wound infection in clinical practice update:2016

This update provides an opportunity to explore contemporary advances in wound infection knowledge and practice. Since 2008, scientific and clinical understanding of chronic wound infection has developed significantly. In particular, awareness of the presence and impact of wound biofilm has advanced enormously; however, understanding of its pathogenesis is yet to be clarified fully. A holistic approach to individuals with, or at risk of, active wound infection remains essential to best practice in prevention, identification and management of wound infection. This is of particular importance in the context of increasing antibiotic resistance. IWII Consensus_

Should prophylactic negative pressure wound therapy be used after Caesarean section?

Echebiri and colleagues have recently evaluated the economic benefit of prophylactic negative pressure wound therapy (NPWT) on a closed laparotomy incision after cesarean delivery in comparison with standard postoperative dressing. Their cost-benefit analysis suggests that negative pressure wound therapy should not be used on closed laparotomy incisions of patients with low risk of postcesarean delivery surgical site infections. However, among patients with a high risk of surgical site infections, prophylactic negative pressure wound therapy is potentially cost-beneficial.

To evaluate the economic benefit of prophylactic negative pressure wound therapy on a closed laparotomy incision after cesarean delivery in comparison with standard postoperative dressing.

METHODS: We designed a decision-analytic model from a third-party payer’s perspective to determine the cost-benefit of prophylactic application of negative pressure wound therapy compared with standard postoperative dressing on a closed laparotomy incision after cesarean delivery. Our primary outcome measure was the expected value of the cost per strategy. Baseline probabilities and cost assumptions were derived from published literature. We conducted sensitivity analyses using both deterministic and probabilistic models. Cost estimates reflect 2014 U.S. dollars.

RESULTS: Under our baseline parameters, standard postoperative dressing was the preferred strategy. Standard postoperative dressing and prophylactic negative pressure wound therapy cost $547 and $804 per strategy, respectively. Sensitivity analyses showed that prophylactic negative pressure wound therapy can be cost-beneficial if it is priced below $192; standard postoperative dressing is the preferred strategy among patients with surgical site infection rate of 14% or less. If surgical site infection rates are greater than 14%, prophylactic negative pressure wound therapy could be cost-beneficial depending on the degree of reduction in surgical site infections. At a surgical site infection rate of 30%, the rate must be reduced by 15% for negative pressure wound therapy to become the preferred strategy. Monte Carlo simulation of 1,000 patients in 1 million trials showed that standard postoperative dressing was the preferred cost-beneficial strategy with a frequency of 85%.

CONCLUSION: Our cost-benefit analysis provides economic evidence suggesting that negative pressure wound therapy should not be used on closed laparotomy incisions of patients with low risk of postcesarean delivery surgical site infections. However, among patients with a high risk of surgical site infections, prophylactic negative pressure wound therapy is potentially cost-beneficial.

Latest research from WOUNDS

In a article published in WOUNDS, December 2014, Gibson and colleagues sought to determine whether silver-containing dressings and medical-grade honey gel interfere with one another in measurable ways. The authors conclude that for the purposes of autolytic debridement, the evidence in this study suggest that silver dressings will not interfere with medical honey’s osmotic mechanism, and that the combination will still possess at least the same antimicrobial activity of a non-collagen silver dressing if used.

To download the article go to: http://bit.ly/1Ioqmlu

News updates July/August 2013

News updates for August 2013 have now been uploaded here , including:

  • An updated Cochrane review of adjunctive G-CSF in diabetic foot infections. Cruciani M et al. Cochrane Database Syst Rev. 2013.
  • ROSSINI study results, which demonstrated a baseline wound infection rate of 1:4. Pinkney TD et al. BMJ. 2013.
  • Plus papers on: Risk of MRSA SSI in patients with MRSA colonization (Kalra et al. 2013), and influence of DSWI on survival following cardiac surgery (Colombier , 2013), and more.

A report on the first Wound Infection summit which took place at Kings College Hospital, London on 20 March 2013 can be downloaded here.

The news update for July can be found here.

International Wound Infection Institute – 2012 wound care publication retrospective

A review of interesting publications in the field of wound infection in 2012

 

This 2012 retrospective reviews interesting articles published in the field of wound infection in 2012. Articles include:

  • The new update and review on the TIME (Tissue, Moisture, Infection/Inflammation, Edge of wound) approach to wound bed preparation produced by Professor David Leaper and colleagues.
  • Findings by Maddocks and colleagues at Cardiff Metropolitan University that manuka honey demonstrates bactericidal effects against Streptococcus pyogenes cultures, including biofilms.
  • Updated and new Cochrane reviews on the efficacy of water as a wound cleansing agent, antibiotic prophylaxis for postoperative wound infection, and pre-operative interventions for preventing infection – plus a review of 44 Cochrane Wounds and Peripheral Vascular Diseases Group reviews.
  • Clinical practice guidelines for the diagnosis and treatment of diabetic foot infections, released by the Infectious Diseases Society of America.

Are wound biofilms visible? An interesting controversy

Two letters published in the Journal of Wound Care discuss clinical practice in wound biofilm identification

 

A letter by Richard White (University of Worcester) and Keith Cutting (Perfectus Medical) published in the March 2012 issue of the Journal of Wound Care* stated that while the use of experimental models and circumstantial evidence has established the existence of wound biofilms, as yet there is no conclusive clinical/in vivo proof to support this. In particular, they observe that there is no evidence of visual biofilm identification which is supported by microscopic confirmation. They argue that clinical understanding of wounds and wound biofilms must be based on firm science.

In a response published in the April 2012 issue of the Journal of Wound Care*, Jennifer Hurlow (Plastic Surgery Group) argues that, with a trained eye and clinical experience, wound biofilms can likely be differentiated from slough without the need for in vitro validation. She notes that an increasing number of practices and studies are using clinical cues to identify biofilm presence, and points out that awaiting microscopic confirmation of biofilm presence before taking appropriate action might not be in the best interests of the patient.

*Letters reproduced with permission of the Journal of Wound Care: www.journalofwoundcare.com.

Wound infection – an expert snapshot

It’s time for woundcare to be counted

On passing the 500 member milestone, we touched base with Dr Douglas Queen and Professor David Leaper (secretary of the IWII, pictured) at the Wound Healing Research Unit in Cardiff, Wales. This was an opportunity too good to miss.

Tapping Doug’s experience as a journal editor and consultant working internationally in wound care, along with David’s considerable policy forming experience in the field gives us an expert snapshot of wound infection at the end of 2009.

Q: What direction is wound care going in as we near the end of the 1st decade of the 21st century?

Doug: Over the last 10 years the emergence of silver dressings has heightened awareness of wound infection and the problems it generates, helping wound care to emerge as a clinical speciality. Where will it take us? I think the emergence of point of care diagnostics for infection will be the next big development, with routine assessments being made on a technological as much as an expertise basis.

David: I agree. In addition to silver we are seeing the emergence of biguanides, already well established in Europe, and the emerging evidence that they could be as good as silver and possibly cheaper. There will also be a big focus on biofilms and our understanding of them. Some biofilm detection diagnostic is required such as a device that can brush wounds, for example, before you start putting antiseptics on them to make their antibacterial activity more extensive. There is huge pressure to innovate in this area. But one area where I would really like to see change is political, on the positioning of wound care and on the role of randomised control trials (RCTs).

Doug: RCTs will never be the gold standard for wound care because the patients are too complex. We should get round this with individual clinicians coming up with and publishing real live data on wounds that will be more effective.

David: That’s right. Compression, for example, corrects an underlying vascular (venous) problem, so RCTs can be very useful, but wound care has multiple causes.

There is a well designed RCT that suggests that on wounds, any dressings can be used, and that silver is no better for wound healing than any other dressing. It’s a good RCT but with a flawed hypothesis in my view. Silver was never marketed to heal wounds, it’s there to treat infection. the rigid idea that everything has to be RCT driven is wrong, at least for wound care, and someone should go to government and state that case. The outcome of this recent study was predictable and it will have been an extensive use of Department of Health (UK) generated funds.

Also, the government must accept the whole concept of reducing the use of antibiotics. In primary care, if you get a wound complication you will almost certainly be given an antibiotic. A major role for the International Wound Infection Institute, for example, could be developing a political agenda that addresses these issues.

Doug: It’s true that wound care has been too passive. Governments are becoming interested in treating wounds, but from other aetiological perspectives. For example Scottish Enterprise has funded an infection diagnostic for Diabetic Foot Ulcers for £8 million. It’s not wound care but who cares?

Q: So you think that harnessing individual clinical experience is the way forward?

David: Yes, and there are some journals that are doing that. But an educative group supported by governments, a 7 or 8 nation push would be good.

Doug: Ultimately a body like the IWII could be able to influence these bodies; the IWII needs to get critical mass, because wound care needs to have a voice that can influence decision makers.

Q: If you are a decision maker in a government organisation, able to influence the provision of wound care services, what would you be looking for in a web site like ours?

David: Concrete recommendations like those generated by NICE or SIGN are what many practitioners want. Any organisation that tackled dressings in a similar way would make a great contribution. That would be a major job, 2 or 3 years, and then perhaps we would really progress.

In terms of other ideas, a roadshow would be wonderful. Having joined one on surgical site infections with the Infection Protection Society I think you can reach many people that way, handing out useful material. With our international committee and our 500 members, we have a lot more clout than we might think.

Q: Going back to where we started, are there any other agents that will emerge for wound infection in the future? Iodine, for example?

Doug: Yes, that is coming back into fashion because of its action on biofilm but also due to concerns with resistance.

David: Sugar is another agent that has a known antibacterial effect and I’d like to see a comparison with honey, because specific honeys are marketed for wound care!

Q: And the focus on biofilms?

David: This is because it’s seen as a new concept. Dentists have known about them for a long time and in the past few years these have been recognised in wounds. As I mentioned, diagnostic tools for biofilms are going to be a big focus in the next few years.

Q: We have had a great deal of comments on biofilms and critical colonisation, what the connection is, whether they are one and the same thing. Do you have any thoughts on this?

David: There is probably a link between biofilms and critical colonisation, but there is no diagnostic for this.

Doug: I agree with David, it sounds very exciting but has not been validated clinically.

Q: So the big things for the IWII are?

David: Education and politics

Doug: The cost of wound care is far more than the cost of dressings. The expenditure on treating wounds worldwide is at least $70 billion, and infection management is central to wound management. So politics, yes, it’s time for wound care to be counted.