Experimental Observations ON THE ANTISEPTIC ACTION OF HYPOCHLOROUS ACID AND ITS APPLICATION TO WOUND TREATMENT

Safety of troclosene sodium solution in decontamination of wounds: A prospective clinical and laboratory study

Debate persists regarding the safety of hypochlorite-containing solutions in the decontamination of infected wounds. In 2006, the Israeli Ministry of Health withdrew licensing approval for troclosene sodium as a wound irrigation solution. The aim of this prospective clinical and laboratory study was to investigate the safety of troclosene sodium solution for decontamination of infected wounds. Troclosene sodium solution was used to treat 30 patients with 35 infected skin wounds of various etiologies and body areas, over a treatment period of 8 days. Data were gathered according to a prospectively designed protocol including general findings, wound-specific observations on Day 1 and Day 8 and laboratory parameters on Day 1 and Day 8. Wound swabs and tissue biopsy for culture were taken on Day 1 and Day 8. Statistical analysis was executed. Tests were 2-sided and p values of <0.05 were considered statistically significant. Eighteen males and 12 females, with 35 infected skin wounds were enrolled. There were no adverse clinical events. No significant changes were observed in general clinical observations. Statistically significant improvements were observed in: pain (p < 0.0001); edema (p < 0.0001); area of wound covered by granulation tissue (p < 0.0001); exudate (p < 0.0001); and erythema (p = 0.002). Prior to treatment, bacteria were demonstrated on microscopy or on culture in 90% of wound samples. On Day 8, this frequency reduced to 40%. There were no abnormal laboratory tests. Serum sodium concentration increased significantly between Day 1 and Day 8, whilst serum concentration of urea and concentrations of thrombocytes, leucocytes and neutrophils showed statistically significant reductions, but all values remained within normal laboratory ranges throughout the study period. Troclosene sodium solution is clinically safe in the management of infected wounds. These findings were presented to the Israel Ministry of Health and as a result, troclosene sodium was re-approved and licensed for decontamination of infected wounds in Israel.

The Safety and Antimicrobial Properties of Stabilized Hypochlorous Acid in Acetic Acid Buffer for the Treatment of Acute Wounds-a Human Pilot Study and In Vitro Data

Acute wounds may require cleansing to reduce the risk of infection. Stabilized hypochlorous acid in acetic buffer (HOCl + buffer) is a novel wound irrigation solution with antimicrobial properties. We performed a first-in-man, prospective, open-label pilot study to document preliminary safety and performance in the treatment of acute wounds. The study enrolled 12 subjects scheduled for a split-skin graft transplantation, where the donor site was used as a model of an acute wound. The treatment time was 75 s, given on 6 occasions. A total of 7 adverse events were regarded as related to the treatment; all registered as pain during the procedure for 2 subjects. One subject had a wound infection at the donor site. The mean colony-forming unit (CFU) decreased by 41% after the treatment, and the mean epithelialization was 96% on both days 14 (standard deviation [SD] 8%) and 21 (SD 10%). The study provides preliminary support for the safety, well-tolerance, and efficacy of HOCl + buffer for acute wounds. The pain was frequent although resolved quickly. Excellent wound healing and satisfying antimicrobial properties were observed. A subsequent in vitro biofilm study also indicated good antimicrobial activity against Pseudomonas aeruginosa with a 96% mean reduction of CFU, when used for a treatment duration of 15 min (P < .0001), and a 50% decrease for Staphylococcus aureus (P = .1010). Future larger studies are needed to evaluate the safety and performance of HOCl + buffer in acute wounds, including the promising antimicrobial effect by prolonged treatment on bacterial biofilms.

Germicide wound pad with active, in situ, electrolytically produced hypochlorous acid

We describe a new wound dressing technology that can actively generate an inorganic germicide agent, in situ, within the wound pad. The technology provides real time control over the quantitative, spatial and temporal delivery of the germicide. The identity of the germicide is hypochlorous acid (HClO). The HClO is produced in a flexible wound pad, made of a composite of thin (micrometer scale) layers of various materials, with different electrochemical properties that enhance HClO production. Active control over the production of HClO is achieved by control of the pH and of the electric potential across the layers. The effectiveness of the Active HClO Pad (AHClOP) concept is demonstrated in a study on sterilization of E. coli in a deep wound contamination simulating gel. The performance of the AHClOP is compared with that of four commercial wound dressings. Results show that the AHClOP can sterilize throughout the gel, while the commercial dressings cannot.

Fungal Infections After Boston Type 1 Keratoprosthesis Implantation: Literature Review and In Vitro Antifungal Activity of Hypochlorous Acid

PURPOSE

To review the current literature describing cases of fungal keratitis and endophthalmitis after Boston keratoprosthesis (KPro) implantation and to characterize the antifungal activity of 0.01% hypochlorous acid against medically relevant fungi.

METHODS

A literature review of fungal keratitis or endophthalmitis in KPro patients from January 2001 to April 2015, and an in vitro time kill assay characterizing the fungicidal activity of 0.01% hypochlorous acid against fungi causing ocular infections.

RESULTS

Fifteen publications, predominantly retrospective case series, were identified. Infection rates after KPro implantation ranged from 0.009 to 0.02 fungal infections per patient-year of follow-up. The largest single-surgeon series reported an incidence of 2.4% for fungal endophthalmitis during a 10-year period. Causative organisms included both yeasts and molds. Outcomes were favorable if infections were caught early and treated appropriately; less favorable outcomes were reported in developing countries where fungal species are endemic and resources are limited. 0.01% hypochlorous acid is rapidly fungicidal, reducing the number of viable yeast cells or mold conidia by at least 99.99% within 60 seconds. The antifungal activity extended to all molds (Acremonium kiliense, Aspergillus flavus, Aspergillus fumigatus, Fusarium solani, and Mucor indicus) and yeast species (Candida albicans and Candida parapsilosis) tested.

CONCLUSIONS

Fungal infections remain a lifelong concern in patients after KPro implantation. There is a growing need for a standard antifungal prophylaxis regimen, especially in the developing world. The rapid broad-spectrum in vitro fungicidal activity of 0.01% hypochlorous acid against all fungi tested makes it an attractive candidate as an antifungal prophylaxis in KPro patients.

N-chloramines, a promising class of well-tolerated topical anti-infectives

Antibiotic resistance is a growing public health crisis. To address the development of bacterial resistance, the use of antibiotics has to be minimized for nonsystemic applications in humans, as well as in animals and plants. Possible substitutes with low potential for developing resistance are active chlorine compounds that have been in clinical use for over 180 years. These agents are characterized by pronounced differences in their chlorinating and/or oxidizing activity, with hypochlorous acid (HOCl) as the strongest and organic chloramines as the weakest members. Bacterial killing in clinical practice is often associated with unwanted side effects such as chlorine consumption, tissue irritation, and pain, increasing proportionally with the chlorinating/oxidizing potency. Since the chloramines are able to effectively kill pathogens (bacteria, fungi, viruses, protozoa), their application as anti-infectives is advisable, all the more so as they exhibit additional beneficial properties such as destruction of toxins, degradation of biofilms, and anticoagulative and anti-inflammatory activities. Within the ample field of chloramines, the stable N-chloro derivatives of β-aminosulfonic acids are most therapeutically advanced. Being available as sodium salts, they distinguish themselves by good solubility and absence of smell. Important representatives are N-chlorotaurine, a natural compound occurring in the human immune system, and novel mono- and dichloro derivatives of dimethyltaurine, which feature improved stability.

Carcinoma of the ear: a case report of a possible association with chlorinated disinfectants

In this report we present a case of squamous cell carcinoma developing in a mastoid cavity after prolonged exposure to the chemical disinfectant, Eusol. The efficacy and safety of Eusol and other chloric acid (hypochlorous acid) derivatives in clinical use is debated.

Pressure sores. Epidemiology and current management concepts

Pressure sores remain common, with a prevalence of 5 to 9% and more than 70% occurring in patients over 70 years of age. They are often falsely ascribed to poor nursing care, but can more usefully be regarded as a potentially preventable complication of an acute immobility illness. Prevention involves identification of patients at risk, appropriate nursing care measures and the use of special equipment. Much of the special equipment is excessively complex and not validated by clinical trial work. The airwave system, polystyrene bead bed system and Vaperm mattress have been best studied and are effective. Management of the established sore involves treatment of the underlying medical condition(s), attention to hydration and nutrition, prevention of further tissue trauma and the use of special dressings and procedures which facilitate the inflammatory repair response. There is considerable doubt about the use of 'traditional' wound applications such as gauze or chlorinated lime and boric acid solution ('Eusol'). An extensive range of newer products is now available but these have not yet been subjected to controlled clinical trials. A useful starting point is to classify pressure sores into 4 clinical types depending on amount of tissue damage and depth of ulcer. The least severe sore (type 1) can be protected using polyurethane film dressings. Deeper ulcers (types 2 and 3) can be easily and quickly treated by hydrocolloid or alginate dressings which optimise the local wound environment, thus facilitating tissue repair. However, there may be no satisfactory dressing for sacral (near-anal) sores which are more difficult to treat than those at other body sites because of dressing detachment. Cavity ulcers (type 4) can be managed with silastic foam or hydrocolloid or alginate dressings. Debridement of necrotic material is best done manually by scalpel/scissors, although streptokinase/streptodornase (Varidase Topical) may also help if used correctly. Antiseptics have little part to play and ulcers are best cleaned with warm normal saline. Systemic antibiotics are indicated only when surrounding cellulitis is present, although metronidazole is useful for malodorous sores.