In our never-ending attempt to vanquish healthcare-associated infections, the latest weapon to emerge is chlorhexidine gluconate (CHG). Not that CHG is exactly new: as an antiseptic, it has been around for more than 50 years. Initially a topical disinfectant, CHG has recently crept into numerous other products and devices. We now have not only skin antiseptic solutions but surgical scrub products, bathing cloths, oral rinses, intravenous catheters, topical dressings, and implantable surgical mesh -- all infused with this relatively safe, broad-spectrum antiseptic (Table). Nor is the use of CHG limited to the hospital: CHG is increasingly added as a preservative to cosmetics and other personal care products.
Table. Sample of Chlorhexidine Products for Healthcare Use
|Product||Format||CHG Concentration||Healthcare Uses|
|2% or 3.15% With 70% isopropyl alcohol||Skin preparation for surgery, invasive procedures, central lines to prevent SSI and BSI|
|Scrub solution||Liquid detergent (sudsing base)||2% or 4% aqueous||Preoperative showering/bathing General skin cleansing|
|Washcloth||Impregnated single-use washcloth/wipe||2% aqueous||Daily bathing in ICU patients|
|Dental solution||Oral rinse||0.12%||Decontaminate oral cavity (ventilator-associated pneumonia prevention protocols)|
|Gauze dressing||Cotton-weave gauze dressing||0.5% with paraffin||Wounds or burns|
|Catheter dressing||CHG pad or integrated with semi-permeable transparent dressing||2% gel pad or foam disk||Peripherally inserted central catheters Central line dressings|
|Hand rub||Waterless antiseptic hand gel||1% alcohol based with emollients||Hand sanitizer for healthcare personnel (nonsoiled hands)|
CHG belongs to the chemical group known as biguanides. As a biocide, its target is the bacterial cell wall. At low concentrations, CHG binds to the negatively charged cell wall and disrupts its osmotic equilibrium. At higher concentrations, CHG attacks the bacterial cytoplasmic membrane and denatures microbial proteins. CHG has both a rapid onset of bactericidal action and prolonged antimicrobial efficacy through residual effects.
A common question is: against which organisms is CHG effective? The answer is nearly all, depending on the formulation and concentration of CHG used. CHG is bactericidal, virucidal, and fungicidal.
At low concentrations, CHG is effective against most gram-positive bacteria;
At higher concentrations CHG is effective against gram-negative bacteria;
At the highest concentrations, CHG is active against yeasts;
Virucidal activity is good against enveloped viruses (such as HIV, cytomegalovirus, influenza, respiratory syncytial virus, and herpesvirus) but not against "naked" viruses (such as rotavirus, adenovirus, or enterovirus);
CHG has no sporicidal activity, so it is not effective against spores of Clostridium difficile; and
CHG is not active against mycobacteria.
A few months ago, Medscape posted an article about the use of CHG for routine bathing of hospitalized patients (Can We Discard the Traditional Soap-and-Basin Bath?) This article stimulated an influx of comments and questions about the use of CHG in healthcare settings. Clearly, healthcare providers have a great deal of interest (and a few misunderstandings) about CHG.
We took your questions to the following experts and leaders in the field of infection control:
William R. Jarvis, MD, Medscape Infectious Disease Expert Advisor, President, Jason and Jarvis Associates, LLC, Port Orford, Oregon;
Lynn Cromer, RN, MT, CIC, Chair, Association for Professionals in Infection Control and Epidemiology Communications Committee and Infection Control Consultant, Duke Infection Control Outreach Network, Durham, North Carolina;
Rosie D. Lyles, MD, MHA, Division of Infectious Diseases, John H. Stroger Jr Hospital of Cook County, Chicago, Illinois;
Cindy L. Munro, RN, ANP, PhD, Professor, Adult Health and Nursing Systems, Nursing Alumni Endowed Professor, Virginia Commonwealth University, Richmond, Virginia; and
Hudson Garrett Jr., PhD, MSN, MPH, APRN, FNP-BC, Director of Clinical Affairs at Professional Disposables International; Orangeburg, New York.
These individuals contributed to the responses found below.
General Questions About Effectiveness of Chlorhexidine
"Are all of the chlorhexidine products equally effective?" Although CHG is an effective bactericidal ingredient, differences in the product formulations will influence how they should be used. To date, few studies have compared the efficacy of CHG soap vs impregnated washcloths. The wipes have a theoretical advantage over the liquid soap because the CHG in the wipes is not rinsed from the skin and the residual CHG extends the potential for activity.
The antiseptic products (used for prepping skin for procedures or surgery) contain alcohol, which increases the product's effectiveness. Alcohol begins to kill bacteria and inactivate viruses immediately. The aqueous products, which contain only CHG, rely on a cumulative effect for maximum bactericidal activity. This is why patients must begin bathing or showering with aqueous CHG 72 hours before surgery and repeat the bath or shower 2 days and then 1 day before their procedure.
"How cost effective is using CHG compared with soap/water or other agents?" The answer is obvious if you consider the cost savings of more effective antisepsis. Consider these facts:
One surgical site infection (SSI) costs $25,546;
For elderly patients, each SSI costs $40,000;
Of course, to be cost-effective, a product must first be clinically effective. Many studies have compared the effectiveness of CHG with that of soap and water, povidone-iodine (most studies have assessed the use of povidone-iodine without alcohol), and alcohol, for various healthcare indications.
Vernon and colleagues compared bathing patients by using CHG-saturated wipes with conventional soap-and-water bathing. They showed that the use of CHG resulted in a 3-fold greater reduction in gram-positive bacteria, a 2-fold greater reduction in vancomycin-resistant enterococci and yeasts, and a 1-fold greater reduction in gram-negative bacteria.
Many studies have documented the effectiveness of CHG bathing and scrubbing in reducing colonization of the skin. However promising these observations, to date they have largely failed to translate into measurable reductions in surgical site infections, although most of the studies have been underpowered to make this determination.
Research demonstrating the effectiveness of CHG for intravascular catheter management has been more positive. A meta-analysis found that the incidence of bloodstream infections was reduced by 49% in patients with central vascular lines who receive CHG vs povidone-iodine (without alcohol) for insertion-site skin antisepsis. Although CHG costs more than povidone-iodine, it is cost-effective when the reduction in costs associated with catheter-related bloodstream infections are considered.
CHG has also been found to be superior to povidone-iodine for skin cleansing immediately before surgery. Darouchie and colleagues found that after clean-contaminated surgery, a CHG-alcohol skin antisepsis product was significantly moreprotective than povidone-iodine (without alcohol) against both superficialincisional SSIs (4.2% vs 8.6%; P = .008) and deep incisional SSIs (1% vs 3%; P = 0.05), but not against organ-space SSIs (4.4% vs 4.5%).
Questions About Bathing With Chlorhexidine
"Our ICU staff gives soap and water baths before CHG baths because CHG will not eliminate visible dirt. Is this really necessary?" Not always. CHG will eliminate visible dirt, according to our experts, and routine "pre-bathing" with soap and water is not needed unless a patient is significantly soiled. In that sense, CHG will never entirely replace soap and water cleaning. The greater the bioburden on the skin, the less any antiseptic will be able to penetrate, so if you really want to reduce the skin microflora, you may need to perform conventional cleaning. Although CHG is effective in the presence of biologic substances such as blood, serum proteins, and pus, its activity is marginally reduced. So a trauma patient, for example, may have to be cleaned with conventional methods first.
"I always thought you couldn't beat soap and water for bathing." Any skin antiseptic (CHG, povidone-iodine, alcohol, or a mixture of CHG or povidone-iodine with alcohol) will reduce the microbial burden on the skin better than regular soap and water. The one situation for which soap and water might be indicated is the patient with Clostridium difficile infection/colonization because none of the skin antiseptics currently on the market will kill C difficile spores. Neither does soap and water, but it does dilute the numbers of spores. To date, this is only a theoretical rationale for soap and water in such patients because no one has documented an increase in C difficile infections when skin antiseptics are used rather than soap and water.
With the rise of antibiotic-resistant microbes in healthcare institutions, the traditional basin bath can be part of the problem, with both basin and water playing roles. Studies have shown that the reusable basin can be a reservoir of contamination, harboring a wide range of organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Furthermore, the hospital water supply can be a source of contamination, perhaps one of the most overlooked sources of contamination in the hospital, particularly with gram-negative bacteria and nontuberculous mycobacteria. CHG-impregnated wipes or washcloths are single-use and disposable, and they require no rinsing, thus eliminating the need for basin and water. Although popular primarily in patients in the intensive care unit (ICU), who need to be bathed in bed, the no-water, no-basin bath is probably a good idea for all patients who are immunocompromised, have fresh surgical wounds, or are otherwise at high risk for infection.
"So, do you see chlorhexidine replacing the soap and basin bath for all hospitalized patients, especially nonambulatory patients (from neonatal to geriatric) in the near future?" This is hard to predict. To date, most studies have been limited to ICU patients (daily bathing) or surgical patients (daily bathing for several days before surgery, and an application with the CHG-impregnated cloth, which is not washed off, right before surgery).[4,6] The effect of CHG bathing in other patient groups has not been well assessed, and even the existing evidence comes mostly from before/after studies, not randomized, controlled trials.
No studies of the use of CHG as a bathing agent in neonates or children have been published, although anecdotally, some neonatal intensive care units (NICUs) are using CHG bathing for all admissions regardless of birthweight. In the future, CHG might replace soap and basin bathing, but more data are needed in a variety of populations.
"We are told to avoid the face when bathing patients with CHG -- either cloths or solution. Are there any other special precautions?" Manufacturers of CHG-impregnated bathing wipes and skin antiseptics state that you should not use the products in the periorbital or eyelid areas. If CHG solutions come into contact with eyes, wash them out promptly and thoroughly with water. You also should avoid contact with the meninges or the middle ear. CHG is toxic to nerve tissues with direct contact, although this has not been reported with currently used agents. In patients with head or spinal injuries or perforated tympanic membrane, the benefit of use in preoperative preparation should be balanced against the risk of contact with these body areas.
"Can CHG be used on the perineum? For example, can we use it on the patient with a Foley catheter?" The best approach is to consult the specific product instructions for use to determine whether the product is safe to use on mucous membranes. Some products will specify that they are not to be used in the genital area.
In general, CHG is not recommended for contact with mucous membranes. The Centers for Disease Control and Prevention (CDC), Society for Healthcare Epidemiology of America, and the Infectious Diseases Society of America, in their compendium of guidelines for prevention of catheter-related urinary tract infection, recommend that "cleaning the meatal area with antiseptic solutions is unnecessary; routine hygiene is appropriate."
One expert responded that if you are bathing with CHG, you can clean the Foley (gently) and the perineum with CHG, but only the external genital region should be cleaned with CHG.
Some CHG products have been safely used for vaginal antisepsis. Recently, CHG was used investigationally in pregnant women as an intravaginal wash, gel, or wipe in an attempt to prevent the vertical transmission of vaginal organisms and reduce neonatal infections. One of the manufacturers of an aqueous CHG 4% product states that "irritation, sensitization, and generalized allergic reactions have been reported with chlorhexidine-containing products, especially in the genital areas."
"Can CHG be used more than once per day? If not, we still need traditional cleansers for incontinent patients." CHG can be applied repeatedly in a single day or sequentially over several days. The manufacturer of a widely used CHG antiseptic/antimicrobial skin cleanser states that the product can be used many times per day without causing irritation, dryness, or discomfort. Studies show that for surgical patients, the application of a CHG bath (applying, letting it dry, and then washing it off) for several days reduces the bacterial load on the skin. Once-daily applications reduce the bacterial load less than twice daily or sequential daily applications. Similarly, single-day applications have a reduced effect on bacterial load compared with multiple-day applications. The best regimens for all patients in all situations (eg, ICU, surgical prep) are still unknown.
Questions About Resistance, Sensitization, and Toxicity of Chlorhexidine
"Can microbial resistance, or reduced effectiveness, develop with prolonged use of chlorhexidine?" Emerging resistance and decreasing susceptibility are always concerns with antimicrobials, antiseptics, and decolonizing agents, and research to monitor the development of these effects is ongoing. Resistance to antiseptics is analogous to antibiotic resistance, and the 2 share some common resistance mechanisms. A manufacturer of CHG products states that "after 50 years of research and experience [there is] still no development of bacterial resistance to CHG."  Milstone and colleagues explain that "although decreasing susceptibility to chlorhexidine has been reported, it has not been convincingly shown to be associated with repeated exposure to chlorhexidine." No case of a patient becoming resistant to the antimicrobial effects of CHG has been documented.
Resistance, if it develops, is most likely to be associated with inappropriate use. Resistance to CHG has been demonstrated readily in the laboratory, notably when low concentrations of CHG are used. Whether the residual amount of CHG left on a surface after CHG use could facilitate emerging resistance is not known. However, until now, most bacteria exhibiting an increased level of resistance to a particular biocide in a laboratory situation have remained susceptible to high concentrations of that biocide.
Gram-negative organisms resistant to CHG have been retrieved from dispensers containing germicidal hand soap with CHG, used for routine hand antisepsis in hospitals. Bacterial contamination with pan-resistant Acinetobacter species or Klebsiella species, multidrug-resistant Pseudomonas species, or MRSA was noted on the surfaces of dispensers of hand soap which contained 2% CHG.
Some strains of MRSA carry genes that confer increased minimum bactericidal concentrations to antiseptics, meaning that it takes a higher concentration of the antiseptic to kill them. However, these concentrations are still well below the concentration of CHG used in clinical practice, so the antisepsis should still be effective. The prevalence of the gene for CHG resistance varies widely in countries around the world, but is still very low considering how long CHG has been used in western Europe. Still, concerns have been expressed that the selective stress exerted by biocides, such as CHG, could favor the growth and dissemination of bacteria expressing resistance mechanisms. It is not known whether the MRSA strains with resistance to CHG are also found in the United States.
"Should we be worried about the toxicity of chlorhexidine?" CHG is not absorbed through intact adult skin. When used properly, adverse reactions to CHG are rarely reported.Because of its cationic nature, CHG binds strongly to skin, mucosa, and other tissues and is thus very poorly absorbed by any route -- skin or gastrointestinal tract. No detectable blood levels have been found in humans after oral use. Percutaneous absorption, if it occurs at all, is insignificant. CHG essentially remains on the skin and is shed with the skin. Therefore, most effects noted with CHG use have been local, consisting primarily of mild skin irritation. Organ damage has been described from accidental exposures; these cases are extremely rare, but the following have been reported:
Corneal injuries and permanent corneal scarring have occurred after inadvertent exposure of the eyes to 4% CHG;
An esophageal burn occurred after ingestion of a large quantity of highly concentrated CHG;
Ulcerative colitis was reported after an enema was given with 4% CHG; and
Contact with the inner ear has caused deafness.
"Are many patients allergic to CHG?" Generalized allergic reactions to CHG have been reported but are extremely rare. Contact dermatitis, urticaria, and anaphylaxis have occurred after repeated skin exposures to this agent. Nodata from western Europe, where CHG has been used for much longer than in the United States, have yet shown that allergic reactions are more common or are increasing. However, if a patient verbalizes a previous allergic reaction to CHG, this should be prominently noted and CHG products avoided in that patient, and patients should always be questioned about previous experiences before using any substance for the first time.
Irritative skin reactions can occasionally occur, but these do not necessarily indicate allergy. It is important to remember that when CHG topical antiseptic is used, the skin must be dry at the time it is applied and the CHG must be permitted to dry. Dressings placed over wet CHG can increase the risk for adverse skin reactions, particularly in low-birthweight infants.
"Why must we use only certain lotions on hands or patients after washing with a CHG product?" The antibacterial activity of CHG depends upon the chemical deposition of the CHG cationic (positively charged) molecule on the skin, where it binds to the stratum corneum. The cationic nature of the CHG molecule helps it to persist on the skin and continue its antibacterial activity, but it is also subject to possible inactivation if an anionic (negatively charged) substance is encountered. It has long been known that anionic-based substances have this diminishing effect on residual CHG. Hand lotions or creams that contain anionic emulsifying agents will reduce the antibacterial effect of CHG.With this information, most healthcare facilities have purchased lotions that are cationic or nonionic (neutral), making them compatible with CHG used by staff or patients.
Questions About Other Uses of Chlorhexidine in Healthcare
"Can you address the use of CHG for vascular catheter insertion preparation?" This is one of the most common uses of CHG products in healthcare settings today. The Infectious Diseases Society of America and The Society for Healthcare Epidemiology of American guidelines recommend the use of a > 0.5% CHG and 70% isopropyl alcohol product for skin antisepsis before vascular catheter insertion to prevent catheter-related infections. This practice can reduce catheter colonization and catheter-related bloodstream infections. It has been found to be superior to povidone-iodine (without alcohol) solutions or plain alcohol. In a randomized, controlled trial of 631 catheter insertions, the incidence of catheter colonization was significantly lower after skin antisepsis with 2% CHG-70% alcohol than with aqueous povidone-iodine (14.2% vs 24.7%; relative risk, 0.5 [95% confidence interval, 0.3-0.8]; P < .01]).Skin antisepsis before vascular catheter insertion is also one of the only currently approved indications for CHG use in the neonate.
Antiseptics such as CHG-alcohol should be applied with sufficient friction to ensure that the solution reaches into the invisible cracks and fissures in the skin. No evidence supports the use of the traditional concentric prepping technique, although this technique is still widely employed.
"Are CHG-transparent dressings effective for central lines?" The skin can never be completely sterilized. At least 80% of resident and transient skin flora is found in the first 5 epidermal layers of the skin. About 20% of skin flora remains on the skin, even after antisepsis, and bacterial re-growth begins immediately (back to the original level by 24 hours). The objective of CHG-impregnated dressings is to continue to suppress bacterial re-growth and to protect the area at the point of catheter insertion, from where it is believed that microorganisms migrate along the catheter insertion tract, to infect the catheter tip.
The CDC and Healthcare Infection Control Practices Advisory Committee recently completed a review of the existing data on the use of the CHG-impregnated sponge (BioPatch®, Ethicon 360, Somerville, New Jersey) and 3M Tegaderm™ CHG (3M, St. Paul, Minnesota). They found no published clinical data on the efficacy of the 3M Tegaderm CHG, and the US Food and Drug Administration (FDA) indication is that this product is a dressing (for securement), without an indication for reducing infection. Thus, the CDC's updated guidelines for the prevention of intravascular catheter-related infections, released in draft form in November 2009, did not mention this product, and the final version of the guideline (to be published soon) will not make a recommendation to use this product for prevention of infection. In contrast, the committee found sufficient evidence to confirm the efficacy of the BioPatch® for the 3 FDA-approved indications: reducing central venous catheter-related bloodstream infections, reducing local site reactions, and reducing skin bioburden. [27-30]
"I've heard conflicting rules about the use of chlorhexidine in the operating room. What is the actual recommendation?" CHG-based antiseptics are widely used for surgical skin preparation in the operating room. The concern about the use of CHG with alcohol (or any alcohol-based product) in theoperating room is the potential for a fire in the presence of the triad of oxygen, electrocautery, and alcohol.
Most such fires occur in the patient's head and neck region because of the proximity to oxygen and the potential for pooling of flammable liquids in the patient's hair or drapes. This situation has occurred most often with the use of the larger, 26-mL antiseptic applicators because a larger volume of antiseptic is used and the drying time is prolonged. Safety measures to prevent an operating room fire include the following:
Use the smallest-volume CHG applicator practical, especially for head and neck surgeries, and prep carefully, avoiding run-off of liquid into hair or drapes;
Do not allow the solution to pool on or under drapes or body areas; remove any wet materials from the area;
Do not drape or use an ignition source until the antiseptic has dried completely and vapors have dissipated (a minimum of 3 minutes -- hair soaked with antiseptic can take up to an hour to dry); and
Make certain that all operating room personnel are educated about the flammability of CHG-alcohol antiseptics and how to prevent a fire; in preoperative briefings and time-outs, remind team of use of CHG.
"How effective is oral CHG, and are there any special precautions for using the oral CHG rinses?" The use of CHG for oral decontamination follows decades of use of this product by dentists in patients with gingivitis and periodontitis. The recent increased use in hospitals has been primarily as an intervention to reduce ventilator-associated pneumonia (VAP) by reducing the number of bacteria able to colonize or infect the upper and lower airways. Several studies have assessed efficacy of this approach, and it has been included in most VAP prevention bundles, although current evidence does not conclusively support the routine use of CHG in mechanically ventilated patients, except in cardiac surgery patients.
CHG is deactivated by anionic compounds, including the anionic surfactants commonly used as detergents in toothpastes and mouthwashes. For this reason, CHG mouth rinses should be used at least 30 minutes after other dental products. For best effectiveness, food, drink, smoking, and mouth rinses should be avoided for at least 1 hour after oral CHG use.
Anionic substances, such as sodium lauryl sulfate, commonly found in toothpaste, also disrupt CHG's cationic activity. For this reason, a time delay between brushing and gargling is advisable.
The most common unwanted effect of using oral chlorhexidine is staining of the teeth. A yellow-brown stain, similar to what occurs with excessive coffee or tobacco use, occurs in about half of patients exposed to the oral solution. However, the staining is highly variable in different individuals, and the cause is not known with certainty. Patients should be advised that this is a normal cosmetic and temporary effect. The stain can be removed with standard professional dental cleaning.
Some patients complain that the use of CHG rinse makes food taste metallic. The alteration in taste should disappear when the oral rinse is discontinued. Clinicians may want to emphasize that use of CHG as a mouthwash without scrubbing or brushing the teeth has minimal impact on the biofilm on teeth. If used with brushing, it removes the biofilm on teeth and reduces oral infection and VAP.
"Can CHG be used on open wounds?" The potential benefits of using CHG and other antiseptics to cleanse wounds is of great interest. Microbial colonization and infection are thought to delay wound healing and even cause wound deterioration.CHG might theoretically reduce the bacterial load of the wound; compared with topical antibiotics, CHG is less likely to encounter bacterial resistance in the wound.On the other hand, concerns about toxicity to local wound healing factors and possible reduced activity in the presence of wound exudate or blood remain to be addressed.
In the limited human research to date, CHG appears to be safe and does not interfere with wound healing. CHG may favor healing of open wounds at risk for infection. However, the evidence to date has not sufficiently assessed the efficacy and safety of CHG for wound care, so no conclusions can be drawn.
The topical antiseptic, which contains alcohol, should not be used on open wounds because it could burn the tissues. Aqueous CHG has been used, in very low concentrations (0.012%), to clean superficial wounds. In this manner, CHG will neither cause additional tissue injury nor delay healing.Product information for a popular brand of aqueous CHG states that wounds that involve more than the superficial layers of the skin should not be routinely treated with the product. For superficial wounds, the area should first be rinsed with water, then the wound area should be covered with the minimum amount of solution necessary, and rinsed thoroughly afterward.
"Have any studies been conducted on the use of CHG in neonates?" Most CHG products are approved for use only in patients over the age of 2 months; therefore, this excludes neonates. The only indication for the use of CHG in neonates is preparation of skin before intravascular catheter placement
That said, anecdotally we know that CHG is widely used in NICUs across the country. A recent comprehensive review concluded that some percutaneous absorption of CHG occurs in neonates at trace levels, particularly in preterm infants.
Therefore, the safe use of CHG on neonates with underdeveloped stratum corneum has not been established. One of the few published studies of neonatal use is a randomized, controlled trial in a NICU looking at CHG-impregnated sponge dressings for the prevention of catheter-related bloodstream infections. Although the patches did reduce bloodstream infections, local infections, and skin bioburden, many adverse skin reactions to CHG occurred in very-low-birthweight infants.
Use of this product should probably be delayed until about 1 week of age (when the skin has matured) in infants who are very premature or low birthweight. This CHG-impregnated sponge dressing also has been tested in older infants and children without demonstrating any adverse events.
With respect to perinatal use, if CHG has been used for cleansing the mother's skin, the mother's nipples should be washed thoroughly with water before breast-feeding. One neonate was reported to develop multiple episodes of bradycardia and cyanosis, with serum chlorhexidine concentrations of 11 ng/mL after oral exposure when CHG was used on the mother's breasts to prevent mastitis.
"Is chlorhexidine bathing for VRE-/MRSA-positive patients recommended in long-term care?" This is a difficult question. To date, the studies done in ICU patients suggest that daily CHG bathing will reduce the risk for VRE colonization and of VRE bloodstream infection. These same studies have not shown a significant reduction in MRSA colonization or MRSA bloodstream infection (probably because the CHG is not placed intranasally, where MRSA usually resides). Studies also show that CHG bathing used prophylactically before surgery or as a surgical prep (on the day of surgery) reduces the surgical site infection rate. Hopefully, data looking specifically at long-term care patients will be forthcoming.
Medscape Nurses © 2010 WebMD, LLC
Cite this: Laura A. Stokowski. Chlorhexidine in Healthcare: Your Questions Answered - Medscape - Aug 04, 2010.