By Thomas L. Kovach, MA
Intact Skin: The First Line of Defense.
Infectioncontrol professionals conclude that proper handwashing by nursing staff,physicians, and patients is the single most effective method for controllingcross-contamination potential in healthcare institutions-especially in acutecare areas of the hospital.1,2,3 Most patient handling episodesexpose the healthcare worker to potential infection by opportunisticmicroorganisms establishing and moving into a "chain of septic flow."A chain of septic flow is defined as the movement of possible disease-causing,opportunistic, transient microorganisms moving from surface to surface (i.e.,nursing staff hand-to-hand; from the patient to the hands of the nursing staffand back again to nursing staff hands; another patient; hospital equipmentsurfaces). Nursing professionals can manage this problem by establishing andmaintaining an "intact aseptic link" to inhibit a chain of septic flowfrom occurring.4
A major challenge for the healthcare worker in managing this problem thoughis the ability to maintain moist and intact skin on hands during a patient careday. Since patient care protocols require handwashing episodes exceeding 25times per day, this becomes a difficult task. Maintaining intact skin duringhandwashing is a natural "first line barrier defense" and helps topreserve an intact aseptic link in the chain of septic flow against thisopportunistic and pathogenic microorganism threat. Maintaining intact caregiverskin could be disruptive to any potential chain of septic flow during patienthandling episodes and would be an additional safeguard to the caregiver. Notedprofessionals in the field of infection control and handwashing have alreadydiscussed the problem of necessary skin integrity during daily-requiredhandwashing.5
The Centers for Disease Control and Prevention (CDC) in Atlanta, Ga, andother professionals in the field of infection control suggest that individualcaregivers represent the most effective control point to prevent the spread ofopportunistic and pathogenic microorganisms.6 The normal approach inmanaging this cross-contamination problem is with proper handwashing using ahealthcare personnel handwash/ antimicrobial skin cleanser or antimicrobial handrinse before and after each patient-handling episode.
There are many handwash product formulations with a variety of activeingredients effective in breaking the potential "chain of infection."These handwashing products are generally known as a healthcare personnelhandwash or hand rinse. Most active ingredients work to inhibit, to a more orless degree, opportunistic/pathogenic microorganism flow associated with thechain of infection. Most of these active ingredients have been available to theprofessional healthcare community for a number of years. However, despite theirefficacy, many can have degrading and drying effects on hands.
A search of current literature suggests that no or few new active ingredientsin handwashing formulation have come on the market during the last 20-plusyears. In addition, nursing staffs have found that repeated use of activeingredients in handwash or hand rinse formulations can and do result in dryingout their skin, which can become a source of skin irritation. Moreover, the useof powdered latex gloves together with the use of handwash formulations canresult in rough, red, chapped skin, which can lead to broken skin conditions onthe epidermis of caregiver hands.
Current handwashing and hand rinse products normally contain one of thefollowing active ingredients: Chlorhexidine gluconate (known as CHG);Chloroxlyenol (known as PCMX); Triclosan; isopropyl alcohol, ethyl alcohol,normal-propyl alcohol; and sometimes iodine. All of these active ingredientsserve to inhibit transient pathogenic microorganisms to some degree. Some arebetter than others in the ability to inhibit opportunistic microorganisms duringthe initial application and in the important characteristic of persistent logreduction over time.
Striving for Balance.
Historicallyand in general, effectiveness in log reductions of microorganisms has beenachieved at the expense of harsh formulations that degrade the hands of thecaregiver. There seems to have been a trade-off between antimicrobialeffectiveness and gentleness. Increasingly, manufacturers are searching to finda "balance" between antimicrobial effectiveness (both in the initialand persistent log reduction) and mildness to the hands of the caregiver.Achieving both goals would represent a superior weapon in managing the problemof opportunistic microorganism flow and the transmission of disease inside ofhealthcare institutions. If achieving infection prevention did not involvedegrading hands, there might be considerable less caregiver resistance tofrequent handwashing protocols and thereby a reduction in nosocomial infectionrates.
The ideal handwash or hand rinse should have good to excellent initial logreduction properties and demonstrate lasting persistence through log reductioncapability during the patient care day against opportunistic gram positive andgram negative microorganisms. It should also be gentle to the caregiver's skinby not removing the moisture content of the skin after repeated use. If oneaccepts the notion that intact epidermis skin layers are a normal and naturalline of defense against pathogenic microorganism flow, a handwash formulationthat leaves the epidermis in a supple, moist and intact condition would be asuperior weapon in managing this problem.
While many handwash and hand rinse products are effective to some degree,most formulations dry out the moisture content of the hands. This drying effectis likely a contributing cause of skin irritation and skin dryness thatcompromises intact epidermal skin layers and the natural barrier defense againstthe chain of septic flow. Dry, chapped, cracked, non-intact caregiver handscould be a difficult and even dangerous condition during patient handlingepisodes. If caregiver skin is compromised by a break in the epidermal orstratum corneum layers of the skin, the natural and normal first line of defenseagainst the chain of septic flow can also be compromised. Intact, moist andsupple skin condition also contributes to the ability of the caregiver tomaintain their hands in a fit condition to perform demanding procedures.
Given this background, there is recent research that documents theeffectiveness of current formulations on the market in both initial and logreduction persistence and evidence on how these various formulations moisturizecaregiver skin.
Comparison Testing Data: Effectiveness and Skin Moisture Levels of VariousActive Ingredients Now on the Market.
An independent testing laboratory (BioScience Laboratories, Bozeman, Mont)recently tested the effectiveness of seven known active ingredients along twocriteria:
1. Initial and continued log reduction of standard ATCC microorganismsafter the initial application (initial log reduction-1st handwash) and theseventh daily handwash episode (continued persistent log reduction over time);
2. Incidences of both observed skin irritation and measured moisturecontent after repeated use on hands.
The following seven healthcare personnel handwash and hand rinse formulationswere evaluated for initial and continued log reduction capability of standardATCC microorganism strains. These seven active ingredient formulations were alsoevaluated for the ability to preserve intact skin by retaining or addingmoisture content on the hands of the caregiver. This moisture retention studyinvolved 35 test subjects using five test subjects per handwash productformulation. All subjects' hands were free from clinically evident dermatitis,open wounds, and hangnails.
Finally, users were asked to rank the product attributes for fragrance level,fragrance type, residue left on skin, sticky/tacky feeling after use, skindryness, skin irritation, the degree of clean feeling on skin, and how clean theskin felt.
Serriatia marcescens (ATCC #14756) was used as a marker microorganismto challenge the antimicrobial efficacy for each of the above named seven activeingredients used on the market today. (See Bioscience Laboratories' white paperdescription of detailed methodology titled "A Second Look at QuaternaryAmmonium Compounds as Topical Antimicrobials in the Medical Field," DarylPaulson, PhD, BioScience Laboratories, Inc., Bozeman, Mont7) Table 1illustrates both initial log reduction levels and mean log reductions levelsobtained after the 7th handwash episode. The higher the number the better theproduct worked after the 1st and 7th handwash episode in Table 1.
Table 2 illustrates test results for skin irritation/skin dryness for each ofthe seven handwash/hand rinse formulations. During this phase, 35 subjects wereused for 100 handwash episodes over five days. Both visual assessmentevaluations and retained skin moisture content measurements were performed onone through five test days using the transepidermal water loss (TEWL) techniqueemploying a Corneometer that measures the moisture level in epidermal skinlayers. Visual assessment consisted of "0" being assigned to "novisible damage or perfect skin" to a high value of "6" assignedto hand skin conditions observed as bleeding cracks, deep open fissures, orgeneralized erythematic skin conditions.
Table 1 Results:
All seven formulations demonstrated significant ability to reducemicroorganism loads on the initial application. Table 1 clearly shows CHG 4%,7.5% povidone iodine, CHG 0.75% and benzethonium chloride 0.2% demonstratedsuperior ability of both initial log reduction and persistence build-up overtime. Please note observed log reductions after the initial log reduction in thefirst handwash compared to the observed log reductions after the seventhhandwash episode. Typical of alcohol gels, alcohol achieves an excellent initiallog reduction of microorganisms on the initial application but once evaporated,alcohol loses the characteristic of having persistence in log reductions ofmicroorganisms over time.
Two of the most widely used active ingredients (Triclosan and PCMX) inhealthcare personal handwash and hand rinses did not achieve the log reductionlevels obtained with CHG 4%, 7.5% povidone iodine, CHG 0.75% or benzethoniumchloride 0.2%. The 62% ethyl alcohol gel product did not demonstrate improvedpersistent log reduction over time. Both CHG formulations of 4% and 0.75%, 7.5%povidone Iodine and benzethonium chloride 0.2% achieved significant initial andpersistent log reductions. The benzethonium chloride 0.2% formulation alsoperformed almost as effective in both the initial and persistent log reductionmeasurements as CHG and povidone iodine.
Table 2 Results:
There are two clear winners in the observed skin irritation data. The 62%ethyl alcohol formulation and the benzethonium chloride 0.2% formulationactually added observed moisture to the epidermis of the 35 test subjects overfive days. These two active ingredients performed better than either of the CHGformulations, Triclosan, and PCMX, with povidone iodine irritating the hands toa significant degree.
In addition to the above visual assessment, skin conditions of test subjectswere monitored using the Skin Monitoring Centre TC350 Corneometer and comparedto a baseline measurement of pre-handwash moisture content of the epidermis forall 35 test subjects over five days. All seven formulations and activeingredients were evaluated 14 times over five days. Table 3 is an average ofbaseline adjusted Corneometer values for all tested products. Higher values meanimproved moisture content levels after use over five days and 14 evaluations.
When evaluating Tables 2 and 3, the reader is reminded that handwash and handrinse formulations can be formula dependent. For example, differentmanufacturers using the same active ingredient will vary in the actual impact onthe skin epidermal layers for skin dryness and skin irritation levels afterrepeated use. For example, some active ingredients are well known to cause skindryness or skin irritation. However, a number of manufacturers offerformulations with emollients using the same active ingredient that significantlydiffer in the impact on the caregiver's epidermal skin layers after repeateduse.
Table 3 Results:
From measured moisture content results, three formulations did best-62% ethylalcohol was superior, followed by benzethonium chloride and CHG 4% PCMX, 7.5%Povidone iodine, 0.75% CHG, and 0.3% Triclosan all removed the moisture contentof the epidermal skin layers.
We conclude from Tables 2 and 3 that both benzethonium chloride and the 62%ethyl alcohol formulations consistently improved the epidermal layer of the skinleaving this layer on the hands of the caregiver in a moisturized and intactcondition when compared to other handwash alternatives. In terms ofeffectiveness, Table 1 shows the benzethonium chloride formulation achievedalmost the same log reductions at the 7th wash level as did the CHG 0.75% and7.5% iodine formulations. It is also important to note that benzethoniumchloride had superior log reductions compared to PCMX 1% and Triclosan 0.3% bythe 7th wash and was almost as good as CHG 4% after the initial first washepisode and delivered a significant increase in persistent log reduction versus62% ethyl alcohol. Finally, overall average subjective evaluations by users forfragrance level and type, residue left on skin, less sticky/tacky, low skindryness, irritation levels and skin feeling after use suggests users preferredthe benzethonium chloride 0.2% formulation slightly more than the 62% ethylalcohol formulation and the 0.75% CHG formulation as well as other activeingredient formulations evaluated.
Overall, the better handwash formulation for initial and persistent logreduction seems to be CHG 4%, CHG 0.75%, povidone Iodine and benzethoniumchloride 0.2%.
However, both CHG formulations and especially povidone iodine illustratedskin irritation characteristics. Overall, the 62% ethyl alcohol formulationoffered high moisturization capabilities and excellent initial log reduction ofmicroorganism loads, but like all alcohols did not perform well in demonstratingpersistent log reduction of microorganisms over time and after repeated dailyuse.
Itis understood that most alcohol gel formulations are used as a convenient handrinse, and they do not possess significant "persistent log reduction"capability once evaporated on caregiver skin. While the tested brand of alcoholgel performed very well, in general, alcohol can dry out the skin epidermis ofthe caregiver. This particular formulation has significant emollients added bythe manufacturer--hence its high rating on both moisture retention measures.
Taking all things into consideration, including both the properties of goodinitial and persistent (over time) log reduction capabilities and for leavingcaregiver hands in a moist, intact and supple condition after repeated use, anduser overall ratings, the benzethonium chloride 0.2% formulation seems to offerthe best overall balance of the alternative formulations. It had antimicrobialeffectiveness on the initial application and had persistent log reductioncapability over time. It was almost as effective as CHG 4% and the CHG 0.75%formulations for both initial and persistent log reduction and was consistentlyranked in the top two categories for leaving caregiver hands in a moist, supple,and intact condition. In addition, users rated the benzethonium chlorideformulation as having the best overall ratings for handwash characteristics. P
Thomas Kovach is President of Kovach & Associates Inc., St. Louis, Mo, amanagement consulting firm that specializes in handwashing, infection control,skin care, and wound care topics.
For a complete list of references visit www.infectioncontroltoday.com
Log Reduction for Seven Active Ingredients for AntimicrobialHealthcare Personnel Handwash and Hand Rinse Active Ingredients
1st Initial Handwash and Ranked by Log Reduction after 7th wash
(Higher Numbers Indicate Higher Log Reduction Levels of Microorganisms)
|Ingredient||Initial Log Reduction-1st Wash||Log Reduction-7th Wash|
|2.||7.5% povidone iodine||3.49||3.43|
|4.||0.2% benzethonium chloride||2.40||3.35|
|5.||62% ethyl alcohol gel||3.16||3.06|
Average Assigned Values for Skin Irritation for Seven TestProducts Low to High Ranking After 14 Evaluations During Five Days
Scale: 0 = No Visible Damage/Perfect Skin, 6=Bleeding Hands-High Irritation
|Active Ingredient||Average Observed Assigned Value|
|1.||62% ethyl alcohol||-0.29|
|2.||0.2% benzethonium chloride||-0.01|
|7.||7.5% povidone iodine||+2.07|
Average Corneometer Values for Tested Products During Five Daysof Use and 14 Evaluations High to Low Rankings
Higher + Numbers Indicate Higher Moisture Content. Lower Numbers Indicate LowerMoisture Content
|Ingredient||Average Measured Value|
|1.||62% ethyl alcohol||+13.97|
|2.||benzethonium chloride 0.2%||+3.74|
|5.||7.5 % povidone iodine||-1.55|
|6.||0.7 5% CHG||-2.94|
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