Epic failure: Hyperbaric oxygen therapy for treating chronic wounds

The Cochrane published the review Hyperbaric oxygen therapy for treating chronic wounds (original article)

Here are the results:

  • For diabetes-related foot ulcers, we found that HBOT seemed to improve the chance of healing in the short term (up to six weeks), but not with longer term follow-up. HBOT may reduce the number of major amputations in people with diabetes who have chronic foot ulcers.
  • For chronic wounds caused by a disease to the veins of the leg, we found that HBOT may reduce the size of wounds.
  • For chronic wounds caused by lack of blood supply through the arteries or chronic pressure ulcers, we found no evidence to confirm or refute any effects of HBOT.

These results are to be expected. Not because HBOT is not working, but because researchers lack critical information, simply because it is not available. The Cochrane results are inevitable and reproducible non-conclusive but Cochrane is not to blame. Let’s explain two of the many logical errors causing the failure of wound care research.

It starts with the inclusion criteria. If your inclusion criterion is “a non-healing wound”, you are lost from the start. (the real list is below) There are many reasons wounds do not heal. They can, for example, be patient related, wound related, mechanical or metabolic. (Levels 1,2,3 and 4 which are usually independent of each other)

The first notion regarding chronic wound is that wat caused it, is not necessarily preventing it from closing. Yet we place them all on a pile, sorted by cause of the wound (logical error 1) and then investigate if intervention x is functional. So you are testing in the blind, which is very different from double-blind. That is a gross neglect of reality.

Therefore, if you are lucky,  you will discover how many non-healing wounds accidentally fit your solution (logical error 2). This is very different from finding how effective your intervention is. In today’s setup, it is therefore almost impossible to discover how effective your intervention is. Because we lack markers and/or knowledge to diagnose and characterize the cause of not healing. Therefore, we have no choice but to pile wounds together. It is a pity we do not recognize this beforehand. If you cannot select the wounds which are lacking the solution you provide, the chances of success are next to 0. (logical error 1+2)

And now the real issue: it would be very interesting to figure out which wounds respond. And why and how they respond. This will enable us to recognise this the next time before we apply an expensive treatment. Or in other words, the non-responders are more interesting than the responders. Sadly research is acting in exact the opposite way.

It starts with the inclusion criteria. If your inclusion criterion is “a non-healing wound”, you are lost from the start. (the real list is below) There are many reasons wounds do not heal. They can be patient related, wound related, mechanical or metabolic. (Levels 1,2,3 and 4 which are usually independent of each other)

 

And now the real issue: it would be very interesting to figure out which wounds respond. And why and how they respond. This will enable us to recognise this the next time before we apply an expensive treatment.

If you need help: harmjsmit@gmail.com

 

Inclusion criteria varied in these trials. Doctor 1992 included any person with diabetes with a chronic foot lesion (time not specified); Faglia 1996a included people with diabetes and Wagner grade 2, 3 or 4 lesions (Wagner 1987); Lin 2001 and Kessler 2003 people with “early diabetic feet”, Wagner grades 0, 1 or 2, while Duzgun 2008; Abidia 2003 and Londahl 2010 included people with diabetes whose lesions had been present for more than four weeks, six weeks and three months respectively. In addition, Londahl 2010
required evidence of good standard wound care in a specialist clinic setting for a minimum of two months. Exclusion criteria generally followed from the specific inclusions detailed above, but Abidia 2003 also specifically excluded participants for whom vascular surgical procedures were planned and Kessler 2003 excluded all patients with transcutaneous oxygen tensions of < 30 mmHg. Ma 2013 included patients with diagnosed diabetes, at least one fullthickness wound below the ankle (Wagner grades III or less) for > 3 month, standard care for > 2 month, TcPO2 > 30 mmHg. Khandelwal 2013 included patients with a diabetic foot ulcer of at least 8 weeks duration, patients with only stage III and IV diabetic foot ulcer and the absence of vascular insufficiency.

Leave a Comment

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

*

Deze site gebruikt Akismet om spam te verminderen. Bekijk hoe je reactie-gegevens worden verwerkt.