AESTHETIC FOCUS The importance of skin preparation BY ANNA BAKER With both aesthetic procedures and antibiotic resistance on the rise, good skin disinfection to reduce the risk of infection is more vital than ever. Anna Baker takes us through the evidence behind commonly used skin preparation formulations for aesthetic injectable treatments. he global number of aesthetic the skin [7]. This paper will explore some described as insusceptible, phenotypically procedures performed continues of the commonly used skin preparation tolerant, tolerant or resistant to antiseptics to rise exponentially [1]. The recent formulations used for aesthetic injectable [17]. Consistent with antibiotics, resistance Tdata from The American Society for treatments. to antiseptics can be intrinsic or acquired. Aesthetic Plastic Surgery (2017) confirms Intrinsic resistance, or insusceptibility, to an overall 5.1% increase in the number Chlorhexidine chlorhexidine is demonstrated by bacterial of aesthetic procedures undertaken, Chlorhexidine is a divalent, cationic spores and mycobacteria [17]. In both in comparison to those performed biguanide antiseptic agent that that was cases the outer layers of the cell form an in 2016; as well as a 40.6% increase first described in 1954 [8]. Chlorhexidine impermeable barrier to the ingress of the over the past five years. Furthermore, exists as a gluconate, acetate and molecules [11]. There are inconsistences in non-surgical procedures increased by hydrochloride salts [9]. It has a wide the literature when attempting to define 4.2% in 2017, compared to 2016. As a spectrum of activity encompassing gram- a consensus definition of ‘chlorhexidine consequence, a growing incidence of positive and gram-negative bacteria, resistance,’ as well as in defining a associated complications are described yeasts, dermatophytes, fungi and some robust and standardised method for the [2]. Furthermore, data from the US Food lipophilic viruses [7,10] but is ineffective detection of reduced susceptibility and / and Drug Administration (FDA) in 2017, against bacterial spores [11]. Chlorhexidine or resistance to in-use concentrations of indicates a three-fold rise in adverse at low concentrations is bacteriostatic, chlorhexidine [17]. These are challenging reactions from 2008 to 2011, compared whereas at higher concentrations it can concepts to quantify owing to the gaps and with 2005 to 2007 [3]. be rapidly bactericidal [8]. Chlorhexidine inconsistencies in the literature with scope Alhede et al. reported on a murine acts by binding to the negatively charged for further research. study showing that pseudomonas, bacterial cell wall and affecting the osmotic In contrast, the Medicines and staphylococcus, and propionibacterium equilibrium of the cell [12]. Chlorhexidine Healthcare products Regulatory Agency were all cultured following administration effectively reduces numbers of bacterial (MHRA) issued a warning in 2012 for the of hyaluronic acid, polyacrylamide gel, poly- skin flora, and is available for use in use of chlorhexidine in light of a risk of L-lactic acid and calcium hydroxyapatite aqueous form, combined 70% alcohol and anaphylactic reaction due to chlorhexidine microspheres into the dermal pocket has been used in preparations for hand allergy [18]. A subsequent warning [4]. Furthermore, their findings also cleansing, both general and pre-surgical, for was published in 2017 by the US FDA demonstrated that once biofilm was more than 50 years [13]. reiterating a similar concern, reporting established, treatment with high dose Alongside a broad range of activity, 52 cases of worldwide anaphylaxis due to antibiotics was unable to eradicate the a key advantage of chlorhexidine when chlorhexidine gluconate [19]. In addition, infection. Antibiotic resistance is one of the used as a skin disinfectant, was its in the 46 years between January 1969 most significant threats to patient safety ‘residual activity’ [14]. Furthermore, Aly and June 2015, the FDA reports 43 cases in Europe, fuelled by overuse of antibiotics and Maibach propose that in comparison worldwide. These statistics reinforce and inappropriate prescribing [5]. These to povidone iodine, chlorhexidine can the need for a comprehensive medical cumulative factors emphasise a growing produce a greater reduction in the skin consultation, which includes details need and awareness of utilising adequate flora, as well as exerting a longer residual regarding known sensitivities and allergies. precautions to reduce the risk of associated activity [14], although, irritation of the skin complications, and attention to appropriate and allergic reactions such as dermatitis, Isopropyl alcohol skin disinfection during all stages of a non- are more commonly reported at higher Alcohols are classified into primary, surgical procedure is key [6]. concentrations [15]. secondary and tertiary alcohols, on the Chan et al. propose that the desirable Historically, chlorhexidine has been one basis of the number of carbon atoms traits of a good skin decontaminant of the most frequently used antiseptic linked to the carbon atom that bears the are that it can effectively remove the agents, yet, there are a small number of hydroxyl group [20]. Isopropyl alcohol, contaminant of interest, is readily reports within the literature of bacterial or isopropanolol, is a secondary alcohol, available, acts rapidly, does not enhance resistance to biocides, antibiotic resistance a structured isomer of propranolol, that percutaneous penetration / absorption of effects of biocides, as well as potential for can be produced by combining water and the contaminant, can be readily removed reduced susceptibility to chlorhexidine propene [21]. It is a clear and flammable without residue, and does not damage in staphylocci [16,17]. Bacteria may be liquid that has a moderate evaporation The PMFA Journal | JUNE/JULY 2018 | VOL 5 NO 5 | www.thepmfajournal.com AESTHETIC FOCUS rate and is widely used as an industrial in addition to cytosolic enzymes involved hypochlorous acid [35]. Furthermore, solvent, and cleaning fluid, and is present in the respiratory chain, causing them Robson et al. concur that stabilised in many products, such as lacquers, inks, to become denatured and deactivated hypochlorous acid has rapid and broad- and thinners, as well as household products [25]. In addition, the combination of spectrum antimicrobial activity against [20]. In the EU, it is approved for use in alcohol and iodine has demonstrated clinically relevant microorganisms in vitro cosmetics as a solvent, an antifoaming good effectiveness, in comparison to and in vivo, as long as the narrow effective agent, a perfuming agent, and a viscosity alcohol alone, which may be a result of the pH range is maintained [36]. controller. In light of its antimicrobial immediate germicidal action of alcohol and In vivo, hypochlorous acid is produced activity (which includes multidrug-resistant the residual activity of iodine [30]. Data on in the intracellular matrix in response pathogens, mycobacterium tuberculosis, the systemic absorption of antiseptics is to phagocytosis of pathogens by and a variety of fungi), isopropyl alcohol limited and iodine seems to be absorbed neutrophils and plays an important is accepted as a preservative, and as an from the skin, but more significantly role in the destruction of pathogens. antiseptic in the clinical environment [22.] from mucosa [25], although, this may be The hypochlorous technology has been Alcohol is fast and short acting, with determined by the condition of the skin developed further by Clinical Health broad-spectrum antimicrobial activity, and barrier at the site of application [31]. Technologies to formulate a solution is relatively inexpensive [23]. It is believed Iodine based formulations are highly which has a skin neutral pH which the that alcohols cause membrane damage effective for surgical procedures owing to manufacturer claims to deliver a 6 log and rapid denaturation of proteins, with their broad antimicrobial properties, yet reduction within seconds, with a highly subsequent interference with metabolism the residual, and temporary discolouration oxidising action which is not subject to and cell lysis [11]. Alcohol-based solutions of skin following application may be antimicrobial resistance. Clinisept+ is a that contain chlorhexidine gluconate challenging in terms of practicality for stable, non-toxic, non-mutagenic, and or iodophores are reported to exert a practitioners administering aesthetic non-irritant to skin, eyes and mucosa with sustained and durable antimicrobial injectable treatments. non-cytotoxic properties to new skin cells activity that can persist after alcohol and is designed for topical use, pre and post evaporation [11]. In addition, alcohol-based Chlorine based and Hypochlorous treatment. Hypochlorous has been well solutions can cause irritation if applied solutions described to possess anti-bacterial, anti- to mucous membranes [23]. Isopropyl Sodium hypochlorite was the first sporicidal, anti-fungal and anti-virucidal alcohol remains a popular choice for antiseptic used to prevent infection, as properties [35] and is well positioned as skin preparation for aesthetic injectable demonstrated in the 19th century by the a current, strong contender to meet the treatments, yet, there are reports within pioneering work of Ignaz Semmelweis, demands of a safe, versatile and effective the literature of skin sensitivity and who used it to disinfect hands, lowering skin preparation