EUROPEAN  TISSUE  REPAIR  SOCIETY

Dr Joseph Selkon
Dept of Microbiology, The John Radcliffe Hospital,
Headingon, Oxford OX3 9DU, England

Sterilox TX is produced by electrolysis of a saturated solution of brine. Its main constituent is hypochlorous acid (HOCL) with a 1000 m.v. redox charge, which has extremely rapid biocidal activity against all human pathogenic bacteria, fungi and viruses and also bacterial spores. The D curve shows that 1 log₁₀ of bacterial spores are killed in 11.3 seconds. It is non-toxic to the rabbit eye, non-allergenic in the guinea-pig and not mutagenic (Ames test).

In order to determine whether these properties could be applicable to its use on human skin a series of studies were undertaken by Dr Margaret Hughes and Dr He of the Department of Dermatology at the Churchill Hospital, Oxford to determine its toxicity to skin keratinocytes and fibroblasts. These were grown in monolayer cultures on FCS/DMEB medium. Sterilox at Ph 6.2 resulted in some cell damage or inhibition of proliferation of human fibroblasts up to a dilution of 1:20. With Sterilox at Ph 5.4 there was no inhibition of growth at a dilution of 1:7 and stimulation of fibroblast and keratinocyte proliferation at dilution of ≥1:20.

In view of these findings the ability of Sterilox (Ph 5.4) was studied in respect of its acceptability to patients with chronic lower leg ulcers in terms of pain, discomfort or any other symptoms which might arise from twenty minutes exposure in a Hydrotherapy foot bath. Secondly, quantitative bacterial cultures were carried out to determine its effectiveness in reducing the bacterial load on the ulcer bed.

In all the six patients studied there were no adverse reports from the patients on the comfort of three twenty-minute exposures to Sterilox on each of two days, four days apart. On final assessment after seven days they remained satisfied with the acceptability of this treatment regime and there were no adverse clinical findings.

The bacterial activity showed an impressive reduction of the bacterial count. On the less chronic wounds complete eradication of bacterial load on the wound bed was achieved which was followed by appreciable improvement of wound healing. In the other patients the bacterial load was appreciably reduced by at least 4 x 1og₁₀ and there was substantial growth of granulation tissue and considerable reduction in the purulent discharge.

These results will be discussed to determine whether this frequency of treatment or a more intensive and prolonged regime of Sterilox treatment could be used to enhance healing and whether it has a role in wound preparation for artificial skin grafting.

Dr Steve Thomas
Surgical Material Testing Lab, Princess of Wales Hospital,
Coity Road, Bridgend, CF31 1RQ, England

The practice of introducing live maggots into wounds to effect debridement or combat infection variously called ‘Larval Therapy’, ‘Maggot Debridement Therapy’, or ‘Biosurgery’ has been practiced for over 150 years. This technique, which is highly effective in the treatment of infected or necrotic wounds of all types, was very popular in the early part of the twentieth century but fell into decline with the advent of antibiotics in the 1940s.

Within the past ten years, problems associated with the development of multi-resistant strains of bacteria, coupled with recognition of the limitations of other existing forms of wound debridement, have lead to a resurgence in the use of this ancient technique.

Sterile maggots are now produced in numerous centres throughout the world. Over the five year period, the Biosurgical Research Unit in Bridgend, the only laboratory producing sterile maggots in the United Kingdom, has distributed about 16,000 treatments to some 800 customers in the UK and abroad. Feedback from these customers indicates that the maggots have proved very effective and much anecdotal material published during this period supports the claims made in the early literature.

When introduced into a chronic wound, in addition to removing slough or devitalised tissue it has been reported that maggots can remove unhealthy or malignant tissue leaving the surrounding healthy tissue untouched.

The results of a recent randomised controlled trial that compared maggot therapy with the use of a hydrogel dressing to promote autolytic wound debridement showed a highly significant difference in favour of the maggots in terms of speed of debridement and cost effectiveness.

All this evidence suggests that maggot therapy can no longer be regarded either as a scientific curiosity, or as a treatment of last resort. Rather it should be viewed as a practical and highly cost-effective alternative to conventional dressings or surgical intervention in the treatment of sloughy and necrotic wounds of all types. It has also been shown to be an invaluable tool in the battle against wound infection including that caused by antibiotic resistant strains such as MRSA.

Prof Keith Harding
Director, Wound Healing Research Unit,
The Medi Centre, Cardiff, CF14 4UJ, Wales

Traditionally, wound bed preparation is looked at as the clearance of necrotic and/or sloughy materials from the bed of the wound to product granulation tissue. Whilst this is an understandable approach by the clinician in the belief that until you have removed unhealthy tissue a wound cannot heal, the ways in which this unhealthy material is removed are quite diverse and rely on the subjective assessment of the clinician in determining whether active granulation tissue has been produced in the bed of the wound.

The greatest problem associated with this somewhat crude approach to this aspect of healing is that any clinicians then assume that all that is red on a wound is healthy and all granulation tissue is the same. Experience that we have had in Cardiff has suggested that not all granulation tissue is indicative of a wound progressing towards healing and there is little research data to quantify both the cellular and biochemical aspects of healthy, as opposed to unhealthy, granulation tissue. The need to develop further research in this area is urgent if we are to ensure patients are given optimal care and we are able to produce healing in the most appropriate and timely fashion for an individual patient.

Whilst we need to recognise the need to develop research methodologies to quantify the quality of granulation tissue and the condition of the wound bed, this must be tempered with pragmatic approach to ensuring that we ultimately develop some indicators that are of value to practising clinicians who may not have access to comprehensive research facilities.