Maand: September 2015

Categorieën
General

Diabetic foot guideline reveals poor state of wound care science

Everyone knows diabetic foot wound treatment is challenging and should be undertaken with the utmost care. Even something seemingly simple as callus removal can lead to dramatic complications. The recommendations of the latest guidance on wound healing “IWGDF Guidance on use of interventions to enhance the healing of chronic ulcers of the foot in diabetes” are clear. Provide basic wound care for diabetic foot ulcers, this means clean, debride and take care of callus.  In this guideline there is no text regarding offloading,  vascular, neurological, immunological assessment etc. This does not mean it is not important, it means diabetic wound management is complex and those involved have to make sure they are competent. Do not apply any intervention lightheartedly.

In summary: Never forget to apply basic wound healing principles and know the limits of your expertise, you could very well be liable.

So far the good news.

The underpinning of the first part of this recommendation is as follows: GRADE strength of recommendation: Strong; Quality of Evidence: Low. 

GRADE is used because it appears to be better suited than the normal meta-analysis which provides even more dramatic results.

This means the working group cannot find any better evidence than “LOW” for a recommendation considered cornerstone to wound healing. For some reason I think; if they cannot find it, there is a good possibility it does not exist.

So today, 2015 the only thing we know about diabetic wound care is the experts have strong feelings but lack facts. We feel we should have a clean wound and select dressings based on absorption, comfort and cost. The latest facts could be over 60 years ago when captain Bloom made some observations using cellophane.

This leads to the following conclusions:

  1. We know very little about interventions to enhance healing.
  2. There is a lack of good research leading to recommendations. (cause 1 for finding 1, above)
  3. Most “hot” treatment options lack underpinning because a. they may not work or b. research is not well set up. (See finding 2, above)
  4. Lack of relevant and underpinned findings gives way to the wildest of treatment regimens. (See finding 3, above)
  5. The flurry of “research” and “protocols” might mask relevant findings. Therefore:
  6. We need clear and well-written guidelines until we have our research in order.
  7. To get our research in order, we have to stop doing the same type of research over and over again. (as we did the last 50+ years)
  8. If I am wrong (which I hope) please explain why the guidelines are written the way they are.

Finally, it just might be a good idea to do a reproducibility test on all wound care research. Like the recently done on psychology. Findings in this guideline point towards an even higher non-reproducibility rate for wound care research compared to psychology.

http://iwgdf.org/guidelines/guidance-on-wound-healing-2015-2/

http://www.nature.com/news/over-half-of-psychology-studies-fail-reproducibility-test-1.18248

http://pps.sagepub.com/content/7/6/657.full

 

Categorieën
Level 1

The other natural dressing

The biofilm may be, next to the scab, the other natural dressing. The difference is the biofilm has to be changed like any other dressing.

Animal life and thus humans have evolved in the presence of microbes. This means there always have been bacteria, yeasts and fungi (microbes) in wounds.

It makes no sense for a microbe in a wound to cause an infection. If you kill your host you also destroy your home. As a microbe, it makes a lot more sense to create a situation in which the wound stays open and you and your host live long and (or not) happy.

This open wound situation would be an equilibrium between the microbe on the one end and the human body on the other. If you are a healthy person this will not be a problem. There is a reason we say “time heals all wounds”. Only if you are weakened by age or illness the balance can tip in the “advantage” of the microbe.

The biofilm is part of this game. At the beginning of times the first life was only primitive bacteria, They lived in the sea. They invented the biofilm which glued them to the rock and protected them against the waves and hostile chemicals.

If you as a microbe, want the wound to stay open you have first of all to protect yourself against the host immune system. This means you need a shelter. If not, here you can see what will happen. Apart from keeping it open you also have to protect the host and the wound against trauma and also against other pathogens which might me not so interested in the well-being of the host. During the human development the biofilm has been produced by microbes for this purpose; create and protect a living environment. It is pretty strong and made of sugars, proteins and is glued to the environment using eDNA.

The biofilm is a dynamic shelter or layer which is replaced regularly, animals lick their wounds and you brush your teeth. Apparently replacing it regularly is part of the equilibrium, just like any other bandage. Nature is used to this removal and within hours after removal, the microbe has started on a new biofilm. If this process or balance is disturbed an infection may occur. (in that case nature invented the maggot as a last resource to prevent infection) So the microbe-wound balance is a dynamic process which involves removal and rebuilding the biofilm. It can be disturbed by aggressive pathogens or by weakened hosts (patients).

All in all, I think the biofilm has two functions in the game between the human and the microbe.

  • protect the microbe.
  • protect the host.

All this is nice to know but what are the implications for today’s wound care?

Giving the average condition of our patients it is advisable to deal with biofilms.

The best way to remove a biofilm is to debride the wound. That is a good idea anyway because by debridement you remove also other sources of infection and cell death. As you will understand from above, debriding means cutting, brushing, rinsing and all kinds of other forms of mechanical cleaning.

All in all the biofilm can be seen as a natural bandage. And just like any other bandage you have to change it regularly, check for signs of infection and do not leave it in the body (and certainly not on prostheses.

Treating wounds is a delicate game. Looking at it as a biologist makes a lot of fun and hopefully will help us learn how to hack the wound healing process. If you have a question, just contact me via LinkedIn.

If you think the idea is worth spreading, liking it will help.

Debriding is a medical intervention which only skilled medical professionals are allowed to do. A non-healing wound has to be seen by a specialised doctor or nurse.

Categorieën
Level 4

The question

There is one question wound care specialists typically do not ask. If Winter and Hinman proved the use of cling film speeds up wound healing by 40%, why are there hardly any studies repeating the phenomenon in a clinical setting and do meta-analyses invariably deliver hardly any or no effect.  It seems to me the gap between Winter (animal research, evidence level C), Hinman (evidence level B) +40% and meta-analyses  (evidence level A1) +/- 0% requires an explanation. To me it is a logical question for a logical problem: the gap is too large, we cannot find 40% and 0% outcome at the same time. So who sheds some light on the logic behind the phenomenon?