A study of hydrogen peroxide generation by, and antioxidant activity of, Granuflex (DuoDERM) Hydrocolloid Granules and some other hydrogel/hydrocolloid wound management materials

Honey: An Advanced Antimicrobial and Wound Healing Biomaterial for Tissue Engineering Applications

Honey was used in traditional medicine to treat wounds until the advent of modern medicine. The rising global antibiotic resistance has forced the development of novel therapies as alternatives to combat infections. Consequently, honey is experiencing a resurgence in evaluation for antimicrobial and wound healing applications. A range of both Gram-positive and Gram-negative bacteria, including antibiotic-resistant strains and biofilms, are inhibited by honey. Furthermore, susceptibility to antibiotics can be restored when used synergistically with honey. Honey’s antimicrobial activity also includes antifungal and antiviral properties, and in most varieties of honey, its activity is attributed to the enzymatic generation of hydrogen peroxide, a reactive oxygen species. Non-peroxide factors include low water activity, acidity, phenolic content, defensin-1, and methylglyoxal (Leptospermum honeys). Honey has also been widely explored as a tissue-regenerative agent. It can contribute to all stages of wound healing, and thus has been used in direct application and in dressings. The difficulty of the sustained delivery of honey’s active ingredients to the wound site has driven the development of tissue engineering approaches (e.g., electrospinning and hydrogels). This review presents the most in-depth and up-to-date comprehensive overview of honey’s antimicrobial and wound healing properties, commercial and medical uses, and its growing experimental use in tissue-engineered scaffolds.

Hydrogen Peroxide: Its Use in an Extensive Acute Wound to Promote Wound Granulation and Infection Control - Is it Better Than Normal Saline?

Background: Hydrogen peroxide (H₂O₂) is used as a topical antiseptic in contaminated wounds caused by road traffic accidents. It kills bacteria by producing oxidation through local, nascent, free oxygen radicals. It also removes dirt from the wound due to its frothing action. H₂O₂ is synthesized by various cells as an active biochemical agent that affects cell biological behavior through complex chemical reactions. H₂O₂ has also been used as a wound cleaning agent, removing debris, preventing infection, and causing hemostasis due to its exothermic reaction with blood. Despite its widespread use, there is scanty literature on its use to promote granulation tissue formation. Objective: In the orthopaedics literature, studies on H₂O₂ use are very limited and its potential is underestimated. In the present study, we would like to report our protocol of use of H₂O₂ for its tremendous potential for stimulating granulation and early wound healing. Material and Methods: A total of 53 patients with large acute extensive lower limb contaminated wounds reported to the emergency department have been included with and without lower limb fracture. In group A (43 patients) wound management was done using 7% H₂O₂ and group B (10 patients) was treated by only saline dressing as a control group. Results: In the present study, daily dressing by 7% H₂O₂ solution and provide solution gives excellent results compared to the Saline group. Granulation tissue appeared much earlier with a mean SD 6.3 ± 6.8 days in the hydrogen peroxide group as compared to the Saline group where granulation tissue appeared in 9.3 ± 8.4 days. Conclusion: Spontaneous wound healing is a controlled balance between destructive and healing processes. It is mandatory to remove damaged tissue to promote healing by secondary intention and minimize infection. The dynamic effect of H₂O₂ promotes faster healing, stimulates granulation, and minimizes infection by oxidative stress.

Hydrogen peroxide (H2O2): a review of its use in surgery

Hydrogen peroxide has been used in medicine for more than 100 years. It is known in surgery as a highly useful irrigation solution by virtue of both its hemostatic and its antimicrobial effects. Due to its possible negative effect on wound healing and its cytotoxic effect in higher concentrations, there are concerns about the safety of its use. The objective of this paper is to review the safety and beneficial effects of hydrogen peroxide.

Induction of Low-Level Hydrogen Peroxide Generation by Unbleached Cotton Nonwovens as Potential Wound Dressing Materials

Greige cotton is an intact plant fiber. The cuticle and primary cell wall near the outer surface of the cotton fiber contains pectin, peroxidases, superoxide dismutase (SOD), and trace metals, which are associated with hydrogen peroxide (H₂O₂) generation during cotton fiber development. Traditionally, the processing of cotton into gauze involves scouring and bleaching processes that remove the components in the cuticle and primary cell wall. The use of unbleached, greige cotton fibers in dressings, has been relatively unexplored. We have recently determined that greige cotton can generate low levels of H₂O₂ (5-50 micromolar). Because this may provide advantages for the use of greige cotton-based wound dressings, we have begun to examine this in more detail. Both brown and white cotton varieties were examined in this study. Brown cotton was found to have a relatively higher hydrogen peroxide generation and demonstrated different capacities for H₂O₂ generation, varying from 1 to 35 micromolar. The H₂O₂ generation capacities of white and brown nonwoven greige cottons were also examined at different process stages with varying chronology and source parameters, from field to nonwoven fiber. The primary cell wall of nonwoven brown cotton appeared very intact, as observed by transmission electron microscopy, and possessed higher pectin levels. The levels of pectin, SOD, and polyphenolics, correlated with H₂O₂ generation.

Efficacy of debridement and wound cleansing with 2% hydrogen peroxide on graft take in the chronic-colonized burn wounds; a randomized controlled clinical trial

BACKGROUND

Severe burns are associated with dramatic outcomes which are potentially detrimental. Nowadays the standard treatment for deep partial thickness and full-thickness burn is early excision and grafting, which is not always feasible this leads to chronicity and microbial colonization of burn wounds. Interesting properties of hydrogen peroxide 2% soaked gauze convinced us to use it in management of chronic burn wounds.

METHODS

From January 2009 to September 2011, in a prospective clinical trial, 49 patients (98 limbs) with chronic-colonized burn wounds in both limbs were included in this study. Tissue cultures were taken from all the wounds. For the right, after debridement of granulation tissue and washing with hydrogen peroxide 2% soaked gauze for 5min followed by normal saline irrigation, grafting was done; debridement and skin grafting was performed in the conventional method in left limb wounds. The success rate of graft take was compared between two groups, after 21 days by the surgeon using the formula: Graft take surface area (cm2) x 100%/Total grafted area (cm2).

RESULTS

The study group was composed of 98 limbs in 49 patients with mean age of 26.44±5.66 and burn in 28.3±7.23% TBSA. The most common causes of the burn wounds chronicity was delayed admission associated with poor compliance. (44.8%) Staphylococcus was the most frequent isolate bacterial wounds colonization in our patients. (59.2%) Mean graft take was 82.85% in right limbs, and 65.61% in left limbs; which was significantly different (P<0.05).

CONCLUSIONS

Our study showed that, administration of hydrogen peroxide intraoperatively appears to be safe and significantly increases the mean success rate graft take in chronic-colonized wounds. Therefore, it can be recommended in management of chronic burn wounds management.

Evaluation of LHP® (1% hydrogen peroxide) cream versus petrolatum and untreated controls in open wounds in healthy horses: a randomized, blinded control study

Background

Treatment and protection of wounds in horses can be challenging; protecting bandages may be difficult to apply on the proximal extremities and the body. Unprotected wounds carry an increased risk of bacterial contamination and subsequent infection which can lead to delayed wound healing. Topical treatment with antimicrobials is one possibility to prevent bacterial colonization or infection, but the frequent use of antimicrobials ultimately leads to development of bacterial resistance which is an increasing concern in both human and veterinary medicine.

Methods

Standardized wounds were created in 10 Standardbred mares. Three wounds were made in each horse. Two wounds were randomly treated with LHP^® or petrolatum and the third wound served as untreated control. All wounds were assessed daily until complete epithelization. Protocol data were recorded on day 2, 6, 11, 16, 21 and 28. Data included clinical scores for inflammation and healing, photoplanimetry for calculating wound areas and swab cytology to assess bacterial colonization and inflammation. Bacterial cultures were obtained on day 2, 6 and 16.

Results

Mean time to complete healing for LHP^® treated wounds was 32 days (95%CI = 26.9-37.7). Mean time to complete healing for petrolatum and untreated control wounds were 41.6 days (95%CI = 36.2-47.0) and 44.0 days (95%CI = 38.6-49.4) respectively. Wound healing occurred significantly faster in LHP^® wounds compared to both petrolatum (p = 0.0004) and untreated controls (p < 0.0001). There was no significant difference in time for healing between petrolatum and untreated controls. Total scores for bacteria and neutrophils were significantly (p < 0.0001) lower for LHP^® treated wounds compared to petrolatum from day 16 and onwards. Staphylococcus aureus and Streptococcus zooepidemicus were only found in cultures from petrolatum treated wounds and untreated controls.

Conclusions

Treatment with LHP^® reduced bacterial colonization and was associated with earlier complete wound healing. LHP^® cream appears to be safe and effective for topical wound treatment or wound protection.

Hydrogen peroxide and wound healing: a theoretical and practical review for hair transplant surgeons

BACKGROUND

In most hair restoration practices, hydrogen peroxide has been routinely used to remove blood during and after hair transplant surgery. In other specialties, hydrogen peroxide is also used in these ways: wound cleaning, prevention of infection, hemostasis, and removal of debris. Despite its widespread use, there are still concerns and controversy about the potential toxic effect of hydrogen peroxide.

OBJECTIVE

The objective was to review all available literature including in vivo and in vitro effects of hydrogen peroxide, as well as general wound healing research.

MATERIAL AND METHODS

Literature up to and including the past three decades was investigated.

RESULTS

Two pilot studies were found, and there are not enough data examining the real impact of using hydrogen peroxide in hair transplant surgery. In other specialties, H(2)O(2) appears to have positive effects, such as stimulation of vascular endothelial growth factor, induction of fibroblast proliferation, and collagen, or negative effects, such as cytotoxicity, inhibition of keratinocyte migration, disruption of scarless fetal wound repair, and apoptosis.

CONCLUSIONS

There are not enough data in hair restoration surgery about the use of hydrogen peroxide, and it is unknown and unclear what the optimum dilution should be. Positive and negative effects were found in other specialties. Further studies are recommended. The authors have indicated no significant interest with commercial supporters.

Evidence of oxidative stress in chronic venous ulcers

Reactive oxygen species have been implicated in the impaired healing of chronic leg ulcers but little direct evidence is available. We have observed a significant (p < 0.01) elevation of the allantoin : uric acid percentage ratio, a marker of oxidative stress, in wound fluid from chronic leg ulcers (median 17, range 8-860) compared to both paired plasma (median 2, range 1-8) and acute surgical wound fluid (median 4, range 3-7). However, the allantoin : uric acid percentage ratio did not differ significantly between chronic wounds that healed and those that failed to heal. Neutrophil elastase was elevated 30- to 1300-fold in chronic wound fluid compared to plasma and there was a correlation (r(2) = 0.742) between wound fluid elastase and the allantoin : uric acid percentage ratio. Total antioxidant capacity of wound fluid, as measured with a chemiluminescence assay, did not show a correlation (r(2) = 0.03) with the observed oxidative stress. These observations suggest that conditions of localized oxidative stress, possibly related to neutrophil-associated production of reactive oxygen species, are present in chronic leg ulcers. It is possible that future therapeutic strategies aimed at reducing oxidative stress, in addition to good standard care, could improve healing rates of chronic wounds.

The effect of dilution on the rate of hydrogen peroxide production in honey and its implications for wound healing

OBJECTIVE

Honey is an effective antiseptic wound dressing, mainly the result of the antibacterial activity of hydrogen peroxide that is produced in honey by the enzyme glucose oxidase. Because the rate of production of hydrogen peroxide is known to vary disproportionately when honey is diluted, and dilution of honey dressings will vary according to the amount of wound exudate, it is important to know more about the production of hydrogen peroxide at different concentrations of honey.

DESIGN

The rates of hydrogen peroxide production by honey with respect to honey dilution were measured in eight different samples of honey from six different floral sources.

SETTINGS

Honey Research Unit, Waikato University, Hamilton, New Zealand.

MAIN RESULTS

The maximum levels of accumulated hydrogen peroxide occurred in honey solutions diluted to concentrations between 30% and 50% (v/v) with at least 50% of the maximum levels occurring at 15-67% (v/v). This is equivalent to a 10 cm x 10 cm dressing containing 20 mL of honey becoming diluted with 10 to 113 mL of wound exudate. Maximum levels of hydrogen peroxide reached in the diluted honeys were in the range of 1-2 mmol/L.

CONCLUSION

Significant antibacterial activity can be maintained easily when using honey as a wound dressing, even on a heavily exuding wound. Concentrations of hydrogen peroxide generated are very low in comparison to those typically applied to a wound, thus, cytotoxic damage by hydrogen peroxide is very low.

HPLC analysis of vitamin E isoforms in human epidermis: correlation with minimal erythema dose and free radical scavenging activity

The content and composition of different vitamin E isoforms was analyzed in normal human skin. Interestingly the epidermis contained 1% alpha-tocotrienol, 3% gamma-tocotrienol, 87% alpha-tocopherol, and 9% gamma-tocopherol. Although the levels of tocotrienol in human epidermis appear to be considerably lower than reported in the hairless mouse, the presence of significant amounts of tocotrienol levels leads to speculation about the physiological function of tocotrienols in skin. Besides antioxidant activity and photoprotection, tocotrienols may have skin barrier and growth-modulating properties. A good correlation was found for epidermal alpha-tocopherol (r = 0.7909, p <.0003), gamma-tocopherol (r = 0.556, p <.025), and the total vitamin E content (r = 0.831, p <.0001) with the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging in epidermis, as assessed by electron paramagnetic resonance (EPR) spectroscopy. In human epidermis, alpha-tocopherol is quantitatively the most important vitamin E isoform present and comprises the bulk of first line free radical defense in the lipid compartment. Epidermal tocotrienol levels were not correlated with DPPH scavenging activity. The minimal erythema dose (MED), an individual measure for sun sensitivity and a crude indicator for skin cancer susceptibility, did not correlate with the epidermal content of the vitamin E isoforms. Hence it is concluded that vitamin E alone is not a determinant of individual photosensitivity in humans.

Potential of honey in the treatment of wounds and burns

There has been a renaissance in recent times in the use of honey, an ancient and traditional wound dressing, for the treatment of wounds, burns, and skin ulcers. In the past decade there have been many reports of case studies, experiments using animal models, and randomized controlled clinical trials that provide a large body of very convincing evidence for its effectiveness, and biomedical research that explains how honey produces such good results. As a dressing on wounds, honey provides a moist healing environment, rapidly clears infection, deodorizes, and reduces inflammation, edema, and exudation. Also, it increases the rate of healing by stimulation of angiogenesis, granulation, and epithelialization, making skin grafting unnecessary and giving excellent cosmetic results.

The cytocompatibility of hydrocolloid dressings

The purpose of this study was to evaluate the effect on fibroblast proliferation of hydrophilic particles isolated from six commercial hydrocolloid dressings. The hydrophobic adhesive matrix of six hydrocolloid dressings was removed using a reflux extraction method with an organic solvent (xylene). The remaining hydrophilic particles were dissolved in complete cell growth medium containing 10% (v/v) foetal calf serum and added to confluent human dermal fibroblasts grown in monolayer in final concentrations of 0.1 and 0.01% (w/v). Control cells received growth medium alone. The fibroblasts were incubated with the hydrophilic particles and the thymidine analogue 5-bromo-2'-deoxyuridine (BrdU) for 24 hours. The incorporation of BrdU into DNA was used as a measure of cell proliferation and determined using an ELISA kit. The results were expressed in percentage of control-treated wells and analysed using analysis of variance. Apart from Comfeel Plus, the hydrophilic particles of hydrocolloid dressings significantly inhibited fibroblast proliferation at 0.1% compared to control-treated fibroblasts (p < 0.05).

Topical hydrogen peroxide treatment of ischemic ulcers in the guinea pig: blood recruitment in multiple skin sites

BACKGROUND

Oxygen deficit is a key factor associated with delayed healing of ischemic wounds in human beings. Topical oxygen-releasing compounds such as hydrogen peroxide or tetrachlorodecaoxide have been suggested as therapy for ischemic tissue.

OBJECTIVE

Our purpose was to monitor the effect of hydrogen peroxide cream on the process of ischemic ulcer healing with a model for ischemic ulcers in the guinea pig.

METHODS

Measurement of vascular perfusion with a laser Doppler velocimeter and gross observations of percentage of nonnecrotic wound surface were made on ischemic wounds in guinea pigs after treatment with either a hydrogen peroxide cream or a placebo cream.

RESULTS

Visual evaluations of the percentage of nonnecrotic wound surface showed no statistically significant differences among the treatments. In contrast, vascular perfusion measurements resulted in statistically significant differences. Blood flow was significantly higher up to day 15 in ulcers treated with 2% hydrogen peroxide cream than in those treated with placebo cream. Vascular perfusion was significantly higher in ulcers treated with 3.5% hydrogen peroxide cream than in ulcers treated with either 1.5% hydrogen peroxide cream or placebo. Adjacent control sites in guinea pigs whose ulcers were treated with hydrogen peroxide cream showed increased vascular perfusion compared with corresponding sites in animals whose ulcers were treated with placebo. Even distant flank control sites of ulcers treated with 3.5% hydrogen peroxide cream showed increased vascular perfusion.

CONCLUSION

Treatment of ischemia-induced ulcers with hydrogen peroxide cream enhanced cutaneous blood recruitment not only to ulcers and adjacent sites, but also to distant sites.

Quantification of hydrogen peroxide generation by Granuflex (DuoDERM) Hydrocolloid Granules and its constituents (gelatin, sodium carboxymethylcellulose, and pectin)

The hydrogen peroxide generating capacity of Granuflex Hydrocolloid Granules and its constituents (porcine gelatin, sodium carboxymethylcellulose and pectin) was examined using the scopoletin-horseradish peroxidase assay in the presence and absence of catalase. Oxygen purging reduced the formation of hydrogen peroxide by 77-96%. The total concentrations of hydrogen peroxide detected were 1.9 x 10(-6), 1.2 x 10(-6) and 2.3 x 10(-6) mol/l for Granuflex, pectin and gelatin (using 0.5% w/v), respectively, after 48 h incubation in a phosphate buffer, pH 7.4, at 37 degrees C. No hydrogen peroxide was formed by sodium carboxymethylcellulose. The results indicate that hydrogen peroxide generation by Granuflex may be ascribed to its gelatin and pectin components, but not to the sodium carboxymethylcellulose. The release of low levels of hydrogen peroxide into the wound environment could conceivably contribute both to the inflammatory phase and to fibroblast proliferation, and hence to the granulation phase of wound healing.