Suprasorb X PHMB: Antimicrobial And HydroBalance Action .
Product REVIEWSuprasorb X PHMB:antimicrobial and HydroBalanceaction in a new wound dressingWhen a reduction in microbial load of a wound is required, antiseptic dressings can be used. Dressings should beselected for their ability to promote an optimal environment for healing, their lack of cytotoxic effects on humancells and to reduce the selection of resistant bacterial strains. Suprasorb X PHMB is a new antiseptic dressingthat has these properties, combining Suprasorb X, a unique HydroBalance dressing that is able to both absorband donate moisture, with PHMB, an antiseptic compound with no known cytotoxicity or resistance.Andrew Kingsley, Martin Tadej*, Anna Colbourn*, Andy Kerr*, Cathie Bree-Aslan*KEY WORDSWound infectionAntibioticsBacterial resistanceAntisepticsPHMBSuprasorb X PHMBCurrently, there is a greatdeal of interest in the risingprevalence of resistant bacterialstrains such as Methicillin-resistantStaphylococcus aureus (MRSA). Thereis also much criticism surroundingthe indiscriminate use of antibiotics,which is now widely considered tobe a crucial factor contributing to therise of these resistant micro-organisms(Kingsley et al, 2006; Moffatt, 2006).Andrew Kingsley is Clinical Manager Infection Controland Tissue Viability, Northern Devon Healthcare Trust;Martin Tadej* and Anna Colbourn* are Tissue ViabilityNurses and Andy Kerr* and Cathie Bree-Aslan* areTissue Viability Consultants, The Wound HealingCentre, Eastbourne*authors of the case report72WoundsUK,The clinical challenge that resistantbacteria such as MRSA pose towound management is well known(Guyot and Layer, 2006). Guidelinesfor the management of MRSA includethe avoidance of inappropriate orunnecessary use of antibiotics toreduce the likelihood of emergenceand spread of resistant strains (Coiaet al, 2006). As a result, there hasbeen a renewed interest in the use ofantiseptics in wound care. Antisepticsoffer many benefits as they can berelatively easy to use, are widelyavailable, frequently cost less thanantibiotics, and can be administeredwithout prescription (Principles of BestPractice, 2008).However, they too should not beused indiscriminately or indefinitely,as there is also evidence for bacterialresistance to some antiseptics, suchas silver (Maillard and Denyer, 2006),and there is a lack of clinical evidencesurrounding the cytotoxicity of someantiseptic products (Principles of BestPractice, 2008). Cinicians workingin wound care, therefore, have aprofessional responsibility to promptlyand accurately recognise episodes ofinfection and to treat them wisely usingthe most appropriate products for eachindividual clinical situation.surgical or healing by secondaryintention, will become contaminatedwith bacteria to some extent. However,contamination, which describes thepresence of organisms in a wound,with no active growth and no hostresponse, is of no relevance to clinicalpractice (Kingsley et al, 2006). However,when wound bioburden increases,clinical effects may be noted and mayrequire intervention. The WoundInfection Continuum is a useful aidto identifying treatment objectives. Itshould, however, only be used as partof a holistic assessment of the patientand their wound (Gray et al, 2005).The continuum describes the effectsof increasing bacterial numbers inwound tissue, using conceptual namesfor increasingly severe forms of woundbioburden. It can also be used inreverse, to mark the wound’s progresstowards healing (Figure 1). The differentstages are:8 Colonised8 Critically colonised8 Local infection8 Spreading infection (Kingsley, 2006).When should antiseptics be used?It is almost inevitable that the majorityof wounds, whether acute, chronic,Figure 1. The Wound Infection Continuum.2009, Vol 5, No 1p72-77SuprasorbX with PHMB9ok.indd 11225/2/09 11:20:07
Product REVIEWColonised wounds containmultiplying bacteria, however, thehost does not have an overt clinicalresponse or clinical symptoms, meaningthat the need for topical antimicrobialintervention is unnecessary. Onlywhen there are concerns regardingthe patient’s immune response oroverall medical condition should topicalantimicrobials be used prophylactically toprevent an increase in wound bioburden.Indiscriminate prophylactic use ofantimicrobials, including both antisepticsand antibiotics, is not encouraged(Kingsley, 2006; Moore and Gray, 2007).Critically colonised wounds requirea reduction in the level of bacteriapresent, if the wound is to progresstowards healing. In chronic wounds,critical colonisation may cause delayedhealing in the absence of any indicatorsof infection, thus the clinician should bealert to this and microbial involvementmust be suspected when other causesof indolence have been eliminated. Thetopical application of an antimicrobialis probably the most effective way inwhich to reduce the critically colonisedwound’s bioburden to levels that allowthe wound to heal (Sibbald et al, 2001;Fumal et al, 2002). Antibiotics are usuallyunnecessary in the first line of treatmentfor critically colonised wounds.Localised infection is oftencharacterised by the classic signs andsymptoms of inflammation, includingredness, heat and pain (Cutting andHarding, 1994). If local infection isidentified, in most instances, it can bemanaged with topical antimicrobials,providing the practitioner is satisfiedthat the patient’s overall conditiondoes not suggest that there is a riskof the infection spreading. However,the clinician should remain alert to thepossibility of spreading infection, and beprepared to alter treatment as required(Kingsley et al, 2006). If, however,infection has invaded soft tissues or isspreading, then treatment with bothlocal and systemic measures is indicated.Wound dressing choice will have littleimpact on the spreading infection, butcan help to reduce the level of bacteriaat the wound surface and thus helpprevent re-infection.Once the need for topical antisepticintervention has been identified, it isimportant to select a product that willprovide optimum conditions to supportrapid healing. The ability of the agent toreduce or eradicate micro-organisms,must also be considered, along with itsspecificity, cytotoxicity to human cells,its potential to select resistant strainsand its allergenicity (Vowden andCooper, 2006).The ability of the carrier dressing tohandle exudate and remove necrotictissue from the wound is beneficial,since purulent exudate, necrotic tissueand slough are all growth mediums forbacteria (Cutting, 2008). The dressing’sability to reduce malodour, conformto the site and shape of the wound,perform wound bed preparationfunctions, satisfy patients’ expectationsand to meet treatment goals also needcareful consideration (Vowden andCooper, 2006).Antiseptic agentsAntiseptics have been in use for muchlonger than antibiotics yet resistanceto antiseptics presents much lessof a problem. This may be becauseantiseptics differ from antibiotics inthat they are generally active againsta broader-spectrum of organismsincluding common pathogenic anerobicand aerobic bacteria, and fungi. Unlikeantibiotics, antiseptics also tend tohave multiple target sites, includingthe bacterial cell wall or membranes,in the organisms on which they exerttheir effects. This means that the microorganisms are less likely to mountan effective defence and survive asresistant strains (Gilbert, 2006).The range of topical antiseptic agentscurrently in common use in wounddressings in the UK include silver,iodine, and honey. Polyhexamethylenebiguanide (PHMB) is a relatively newentrant to the UK wound care marketalthough it is in common use in Europeand US.Polyhexamethylene biguanidePHMB is a synthetic compound which isstructurally similar to naturally occurringantimicrobial peptides (AMPs). AMPsare produced by the majority of livingorganisms and have a broad spectrumof activity against bacteria, viruses andfungi (Moore and Gray, 2007). AMPsare positively-charged molecules thatbind to bacterial cell membranesand induce cell lysis by destroyingmembrane integrity, in a similar way topenicillin and cephalosporin antibiotics.AMPs are produced by many cellswithin the wound, such as keratinocytesand inflammatory neutrophils, wherethey are thought to play a role inprotection against infection (Sorensenet al, 2003).The structural similarities betweenAMPs and PHMB mean that the lattercan insert into bacterial cell membranesand kill bacteria in a similar way toAMPs (Moore and Gray, 2007).Some bacterial cells use an effluxpump to protect themselves from theeffects of some antiseptics. However,the effect of PHMB on the bacterialcell membrane mean that thepump is unable to remove antiseptic,so bactericidal concentrationsare maintained in the cell. Thismechanism of action is quick andmeans that bacteria are unlikely todevelop resistance to PHMB (Seippand Korber, 2008).PHMB in wound managementPolyhexamethylene biguanide (PHMB)is a commonly used antiseptic whichappears in a variety of productsincluding contact lens cleaning solutions,perioperative cleansing solutions andswimming pool cleaners. Its safety andeffectiveness as an antiseptic bothin vitro and in vivo in these differentapplications is well documented (Motta,2004; Motta, 2005; Larkin et al, 1992).It exerts little toxicity and has been ingeneral use for approximately 60 yearswith no evidence of the developmentof resistance (Moore and Gray, 2007).In wound care, specifically, PHMB haspreviously been demonstrated toblock Pseudomonas aeruginosa-inducedinfection (Cazzaniga et al, 2000) andprevent its degradation of wound fluidand skin proteins in vitro (Werthen etal, 2004). It can also kill a diverse rangeof bacteria and fungi (Lee et al, 2004).Woundsp72-77SuprasorbX with PHMB9ok.indd 113UK,2009, Vol 5, No 17325/2/09 11:20:08
Product REVIEWFigure 2. The unique HydroBalance of Suprasorb X.1. Surplus exudate from the wound is absorbed, and2. Moisture is released from the dressing to lightlyexuding wound areas. 3. Safely removes debris andtraps it within the dressing.Furthermore, to date PHMBhas been used successfully inwound dressings, including nonadherent products, gauze, drains andintravenous sponges (Motta andTrigilia, 2005; Moore and Gray, 2007).The long-term use of PHMB in otherindications without cytotoxicityor the development of resistancesuggests this is unlikely to happenwhen the antiseptic is used in woundmanagement (Gilbert, 2006).PHMB has been incorporatedinto a new wound managementproduct, Suprasorb X PHMB (ActivaHealthcare, Burton-upon-Trent) whichgives antimicrobial activity to the uniqueHydroBalance dressing, Suprasorb X.The Suprasorb X dressing rangeSuprasorb XSuprasorb X dressings have a uniquestructure made up of biosyntheticHydroBalance fibres. These fibres arethe products of a cellulose fermentationprocess using a proprietary strainof Acetobacter xylinium. The bacteriaproduce fibrils of cellulose which are200 times finer than cotton, giving thematerial an exceptionally high surfacearea. The same microbes ‘weave’ a meshstructure of fibrils that enhances bothits moisture handling capabilities and itstensile strength.As a result of the biosyntheticHydroBalance fibres, Suprasorb X is ableto regulate the absorption and donationof moisture at the wound-dressinginterface (Figure 2). Depending on thestatus of the wound, surplus exudate canbe absorbed by the dressing, or donatedin the case of lightly exuding wounds.This moisture absorbing and donating74WoundsUK,a.b.Figure 3. An 86-year-old female with a woundfollowing excision of an infected haematoma usingversajet, followed by two weeks of topical negativepressure therapy. (a) The patient had a history ofsevere wound and urinary tract infection. She alsohas C. Difficile infection, is severely malnourishedand thus is at very high risk of re-infection. (b)Suprasorb X PHMB dressing was applied to thewound to ensure that the wound bioburden remainsat a level conducive to healing.capacity can also be exerted within thesame wound, removing exudate anddonating moisture to drier areas.It also protects the wound againstabrasion, desiccation and externalcontamination. These unique fluidhandling capabilities of the dressingmean that Suprasorb X can be used onmoderately exuding, non-exuding anddry wounds. The moist environmentalso has a cooling effect that hasdemonstrated a significant reduction inpain (Alvarez, 2004; Davis, 2006).In a 24-patient, multicentrerandomised controlled study carriedout by Alvarez et al (2004) todetermine effectiveness of SuprasorbX compared with care already beingreceived in patients venous leg ulcers,Suprasorb X was found to significantlypromote autolytic debridement andsignificantly reduce wound pain atweeks three, six and eight of the12-week study. An improved rate ofwound closure, in terms of increasedepithelialisation and granulation tissuewas also noted (Alvarez, 2004). Resultsof decreased pain, increased granulationand epithelialisation and an improvedrate of wound closure were alsoobserved by Vijverberg et al (2007) andEberlein et al (2007).The new dressing, SuprasorbX PHMB, combines the provenefficacy of Suprasorb X with theantimicrobial action of PHMB (0.3%),and is indicated for use on lightly tomoderately exuding, superficial anddeep, infected wounds in all phases ofwound healing (Figure 3). The PHMBcomponent exerts its antimicrobialeffects both within the dressing,but also at the wound-dressinginterface (Figure 4). As the PHMBis not bound to the HydroBalancefibres of the dressing, it is releasedinto the surrounding fluid along aconcentration gradient.The presence of fluid in the dressingmeans that antimicrobial activity ispossible even on dry wounds, unlikesilver-containing dressings which requirethe mechanical action of wound fluid toinitiate antimicrobial activity.Suprasorb X PHMB in clinical practiceFigure 4. Mechanism of action of Suprasorb X PHMB. Surplus exudate from the wound is absorbedby the dressing, and 2. Moisture is released from thedressing to lightly exuding wound areas. 3. Killing ofmicro-organisms by the PHMB that is released.A clinical case series performed byMulder (2007) to determine theantimicrobial effects of Suprasorb X PHMB showed that PHMB effectivelyreduced wound bioburden and had apositive effect on wound healing. Twelvepatients with a total of 26 woundswere evaluated, 11 of whom hadpreviously been unresponsive to silveror iodine-containing dressings.Wound swabs were taken beforeand after treatment with Suprasorb X2009, Vol 5, No 1p72-77SuprasorbX with PHMB9ok.indd 11425/2/09 11:20:12
Product REVIEW PHMB. Before treatment, organismswere identified in the wounds of eightpatients, most commonly Pseudomonasaeruginosa and Staphylococcus(including MRSA). At the end of theevaluation, levels of bacteria weredecreased in five of the eight patients(two patients were lost to followup, and one patient experienced nochange in bioburden). For the eightpatients, there was a mean reductionin wound size from 6.79cm2 to4.57cm2 in a mean of 25 days. Twowounds healed during the study and13 showed improvement.Similarly, an evaluation of SuprasorbX PHMB in the treatment of 79wounds of varying aetiology by Cavorsi(2006) revealed that healing or clinicalimprovement was achieved in 80%of the cases receiving treatment withSuprasorb X and PHMB. In a subset ofwounds that had not been responsiveto prior treatment with silver dressings,a decrease in wound size of 33% wasobserved after three weeks.An evaluation of Suprasorb X PHMB in the treatment of four patientswith wounds which had previouslybeen treated unsuccessfully withvarious silver-containing dressings wasundertaken by Davis (2006). Althoughtwo wounds were locally infected,application of Suprasorb X PHMBhealed three of the four wounds,protected peri-wound tissue andresulted in a decrease in wound pain(Davis, 2006).Case reportThe patient was an 83-year-old womanwith a history of chronic renal disease,hypertension and venous ulceration ofthe left leg of long duration. On initialpresentation, the wound was sloughyand painful with high exudate levels.These symptoms and the associatedmalodour led to a diagnosis of criticalcolonisation.A reduction in wound bioburdenand progress towards healing was alsoobserved in the following case report.To identify any reduction in bacterialload within the wound bed, a swabwas taken on day one and another onday seven. Photographs were taken atevery visit.On first application of SuprasorbX PHMB the wound measuredapproximately 13cm2 with the woundbed consisting of 90% devitalisedtissue and 10% granulation tissue. Theperi-wound region was fragile but hadevidence of epithelialisation (Figure 5).Microbiological finding showed mixed skin flora.Figure 5. The wound at first assessment.Figure 6. Following one week of treatment withSuprasorb X PHMB.76WoundsUK,A secondary foam dressing wasapplied over the Suprasorb X PHMBand secured with stockinet, woolbandage and double setocrepefor support as the patient had nottolerated compression on previousapplications.The dressing was removed andthe wound reviewed after three days.The dressing had remained hydratedunder the bandaging and foam and wasatraumatic on removal. The wound bedhad improved with a reduction in theamount of devitalised tissue and anincrease in the granulation tissue to aratio of approximately 60/40, however,there was some maceration to theperi-wound area. There had also beena reduction in the overall size of thewound to 9.4cm2 (Figure 6). The woundswab results now showed a reductionin skin flora to just mixed skin flora.The patient responded extremelywell to Suprasorb X PHMB with thewound improving and the bacteriabeing reduced considerably during thetwo-week treatment. The dressing ismoist on application and therefore,fitted the criteria for promoting woundhealing in this patient’s wound.ConclusionThe ideal antiseptic dressing will reducewound bioburden while providinga moist wound environment thatpromotes wound healing. Such adressing, however, must be used wiselyto minimise the cytotoxic effects onthe cells needed for wound healing,and to reduce the selection of resistantbacterial strains (Vowden and Cooper,2006). Suprasorb X PHMB is ableto effectively reduce the number ofpathogens in the wound. Currently,PHMB does not have a history ofresistance or cytotoxicity, making ita good alternative to antiseptics forwhich the development of bacterialresistance and toxicity is an issue.Suprasorb X’s unique ability toabsorb and/or donate moisturedepending on the needs of theindividual wound provides a moistenvironment that will allow the woundto progress towards healing and leadsto a reduction in pain.These unique properties ofSuprasorb X PHMB make it anattractive alternative to the antisepticdressings that are currently available. WUKReferencesAlvarez OM, Patel M, Booker J, MarkowitzL (2004) Effectiveness of a biocellulosewound dressing for the treatment of chronicvenous leg ulcers: results of a single centerrandomized study involving 24 patients.Wounds 16(7): 224–332009, Vol 5, No 1p72-77SuprasorbX with PHMB9ok.indd 11625/2/09 11:20:13
Product REVIEWCavorsi JP (2006) Experience in US withSuprasorb X PHMB — an antimicrobialwound dressing. Poster presentation,EWMA, PragueCazzaniga A, Serralta V, Davis S, OrrR, Eaglestein W, Mertz P (2000) Theeffect of an antimicrobial gauze dressingimpregnated with 0.2% polyhexamethylenebiguanide (PHMB) as a barrier to preventPseudomonas aeruginosa wound invasion.Wounds 14: 169–76Coia JE, Duckworth GJ, Edwards DIet al (2006) Guidelines for the controland prevention of methicillin-resistantStaphylococcus aureus (MRSA) inhealthcare facilities. J Hosp Infect 63(Suppl1): S1–44Cutting KF, Harding KG (1994) Criteria foridentifying wound infection. J Wound Care3: 198–201Davis C (2006) Evaluation of pain controland healing rates using an advancedcellulose dressing with 0.3% PHMB.Poster presentation, SAWC AnnualCongress, TampaEberlein TH, Fendler H, Mustafi N,Sauer B, Schmitz M, Heib A (2007)Exudate management, HydroBa
contamination, which describes the presence of organisms in a wound, with no active growth and no host response, is of no relevance to clinical practice (Kingsley et al, 2006). However, when wound bioburden increases, clinical effects may be noted and may require intervention. The Wound Infection Continuum is a useful aid
Antimicrobials, Aspergillus fumigatus, Antimicrobial Peptides 1. Introduction 1.1. Antimicrobial Peptides and Proteins It is notable that antimicrobial peptides particularly cationic ones play a signifi-cant role within the natural immunity of animal defences against topical and general microbes altogether species of life. These antimicrobial .
Chapter 5: Antimicrobial stewardship education for clinicians 123 Acronyms and abbreviations 126 5.1 Introduction 127 5.2 Key elements of antimicrobial stewardship education 128 5.2.1 Audiences 128 5.2.2 Principles of education on antimicrobial stewardship 129 5.2.3 Antimicrobial stewardship competencies and standards 129
Antimicrobial Peptides 2 ANTIMICROBIAL PEPTIDES OFFERED BY BACHEM Ribosomally synthesized antimicrobial peptides (AMPs) constitute a structurally diverse group of molecules found virtually in all organisms. Most antimicrobial peptides contain less than 100 amino acid residues, have a net positive charge, and are membrane active. They are major
Several groups in the 1970s and 1980s reported antimicrobial peptides produced from leukocytes, including α-defensins from rabbits and humans [10]. One important landmark in the history of antimicrobial peptides is the work of Boman et al. in 1981. Boman injected bacteria into pupae of a silk moth and isolated the antimicrobial peptides
activity mechanisms, and their antimicrobial activity against a broad spectrum of microorganisms, such as gram-positive and gram-negative bacteria as well as fungi, parasites and viruses (23-25 ). 1.2. Antimicrobial peptides - a new class of antibi otics? Antimicrobial peptides are part of the innate immune system and play an important
Virology 15 Mycology 17 Parasitology 17 Interpretation of Viral Diagnostic Tests 19 Antimicrobial Formulary 23 Antimicrobial Costs 25 Antimicrobial Concepts and Tips 27 Antimicrobial Restrictions and . identification and susceptibility testing on most comm
Plant antimicrobial peptides Plants are constantly exposed to attack from a large range of pathogens. Under attack conditions plants synthesized antimicrobial peptides as innate defence. Thionins were the first antimicrobial peptides to be isolated from plants, and normally consists of 45-48 amino acids.
Alex’s parents had been killed shortly after he was born and he had been brought up by his father’s brother, Ian Rider. Earlier this year, Ian Rider had died too, supposedly in a car accident. It had been the shock of Alex’s life to discover that his uncle was actually a spy and had been killed on a mission in Cornwall. That was when MI6 had
