Hand hygiene.pdf

activity of chlorhexidine is not seriously affected by the presence of organic material, including
blood. Because chlorhexidine is a cationic molecule, its activity can be reduced by
natural soaps, various inorganic anions, non-ionic surfactants, and hand creams containing
anionic emulsifying agents 13,266,268 . Chlorhexidine gluconate has been incorporated into
a number of hand hygiene preparations. Aqueous or detergent formulations containing
0.5%, 0.75% , or 1% chlorhexidine are more effective than plain soap, but are less effective
than antiseptic detergent preparations containing 4% chlorhexidine gluconate 227,269 .
Preparations with 2% chlorhexidine gluconate are slightly less effective than those containing
4% chlorhexidine 270 .
Chlorhexidine has significant residual activity 199,207-209,211,227,241,269 . Addition of low concentrations
(0.5–1%) of chlorhexidine to alcohol-based preparations results in significantly
greater residual activity than alcohol alone 209,227 . When used as recommended, chlorhexidine
has a good safety record 266 . Little, if any, absorption of the compound occurs through
the skin. Care must be taken to avoid contact with the eyes when using preparations with
1% chlorhexidine or greater as the agent can cause conjunctivitis or serious corneal damage.
Ototoxicity precludes its use in surgery involving the inner or middle ear. Direct contact
with brain tissue and the meninges should be avoided. The frequency of skin irritation
is concentration-dependent, with products containing 4% most likely to cause dermatitis
when used frequently for antiseptic handwashing 271 . True allergic reactions to chlorhexidine
gluconate are very uncommon (see also Part I, Section 11) 211,266 . Occasional outbreaks of
nosocomial infections have been traced to contaminated solutions of chlorhexidine 272-275 .
Resistance to chlorhexidine has also been reported 276 .
9.5 CHLOROXYLENOL
Chloroxylenol, also known as para-chloro-meta-xylenol (PCMX), is a halogen-substituted
phenolic compound that has been used widely as a preservative in cosmetics and other
products and as an active agent in antimicrobial soaps. It was developed in Europe in the
late 1920s and has been used in the USA since the 1950s 277 .
The antimicrobial activity of chloroxylenol is apparently attributable to the inactivation of
bacterial enzymes and alteration of cell walls 1. It has good in vitro activity against Grampositive
organisms and fair activity against Gram-negative bacteria, mycobacteria and some
viruses 1,12,277 . Chloroxylenol is less active against P. aeruginosa, but the addition of ethylenediaminetetraacetic
acid (EDTA) increases its activity against Pseudomonas spp. and other
pathogens.
Relatively few articles dealing with the efficacy of chloroxylenol-containing preparations
intended for use by HCWs have been published in the last 25 years, and the results of studies
have sometimes been contradictory. For example, in experiments where antiseptics were
applied to abdominal skin, Davies and colleagues found that chloroxylenol had the weakest
immediate and residual activity of any of the agents studied 278 . However, when 30-second
handwashes were performed using 0.6% chloroxylenol, 2% chlorhexidine gluconate or
0.3% triclosan, the immediate effect of chloroxylenol was similar to that of the other agents.
When used 18 times/day for five days, chloroxylenol had less cumulative activity than did
chlorhexidine gluconate 279 . When chloroxylenol was used as a surgical scrub, Soulsby and
colleagues 280 reported that 3% chloroxylenol had immediate and residual activity comparable
to 4% chlorhexidine gluconate, while two other studies found that the immediate
and residual activity of chloroxylenol was inferior to both chlorhexidine gluconate and
povidone-iodine 270,281 . The disparity between published studies may result in part from the
various concentrations of chloroxylenol included in the preparations evaluated, and to other
aspects of the formulations tested, including the presence or absence of EDTA 12,277 . Larson