***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Effective neutralization in testing h and hygiene preparations is considered to be a crucial element to ensure validity of the test results , especially with the difficulty to neutralize chlorhexidine gluconate . Aim of the study was to measure the effect of chemical neutralization under practical test conditions according to EN 1500 . Methods We have investigated two ethanol-based h and rubs ( product A , based on 61 % ethanol and 1 % chlorhexidine gluconate ; product B , based on 85 % ethanol ) . The efficacy of products ( application of 3 ml for 30 s ) was compared to 2-propanol 60 % ( v/v ) ( two 3 ml rubs of 30 s each ) on h and s artificially contaminated with Escherichia coli using a cross-over design with 15 volunteers . Pre-values were obtained by rubbing fingertips for 1 minute in liquid broth . Post-values were determined by sampling immediately after disinfection in liquid broth with and without neutralizers ( 0.5 % lecithin , 4 % polysorbate 20 ) . Results The neutralizers were found to be effective and non-toxic . Without neutralization in the sampling fluid , the reference disinfection reduced the test bacteria by 3.7 log10 , product B by 3.3 log10 and product A by 4.8 log10 ( P = 0.001 ; ANOVA ) . With neutralization the reference disinfection reduced the test bacteria by 3.5 log10 , product B by 3.3 log10 and product A by 2.7 log10 ( P = 0.011 ; ANOVA ) . In comparison to the reference treatment Product B lead to a lower mean reduction than the reference disinfection but the difference was not significant ( P > 0.1 ; Wilcoxon-Wilcox test ) . Without neutralizing agents in the sampling fluid , product A yielded a significantly higher reduction of test bacteria ( 4.8 ; P = 0.02 ) as compared to the situation with neutralizing agents ( 2.7 ; P = 0.033 ) . Conclusion The crucial step of neutralization lies in the sampling fluid itself in order to stop any residual bacteriostatic or bactericidal activity immediately after the application of the preparation , especially with chlorhexidine gluconate-containing preparations . This is particularly important at short application times such as the 30 BACKGROUND Nasal carriers of Staphylococcus aureus are at increased risk for health care-associated infections with this organism . Decolonization of nasal and extranasal sites on hospital admission may reduce this risk . METHODS In a r and omized , double-blind , placebo-controlled , multicenter trial , we assessed whether rapid identification of S. aureus nasal carriers by means of a real-time polymerase-chain-reaction ( PCR ) assay , followed by treatment with mupirocin nasal ointment and chlorhexidine soap , reduces the risk of hospital-associated S. aureus infection . RESULTS From October 2005 through June 2007 , a total of 6771 patients were screened on admission . A total of 1270 nasal swabs from 1251 patients were positive for S. aureus . We enrolled 917 of these patients in the intention-to-treat analysis , of whom 808 ( 88.1 % ) underwent a surgical procedure . All the S. aureus strains identified on PCR assay were susceptible to methicillin and mupirocin . The rate of S. aureus infection was 3.4 % ( 17 of 504 patients ) in the mupirocin-chlorhexidine group , as compared with 7.7 % ( 32 of 413 patients ) in the placebo group ( relative risk of infection , 0.42 ; 95 % confidence interval [ CI ] , 0.23 to 0.75 ) . The effect of mupirocin-chlorhexidine treatment was most pronounced for deep surgical-site infections ( relative risk , 0.21 ; 95 % CI , 0.07 to 0.62 ) . There was no significant difference in all-cause in-hospital mortality between the two groups . The time to the onset of nosocomial infection was shorter in the placebo group than in the mupirocin-chlorhexidine group ( P=0.005 ) . CONCLUSIONS The number of surgical-site S. aureus infections acquired in the hospital can be reduced by rapid screening and decolonizing of nasal carriers of S. aureus on admission . ( Current Controlled Trials number , IS RCT N56186788 . BACKGROUND Since the patient 's skin is a major source of pathogens that cause surgical-site infection , optimization of preoperative skin antisepsis may decrease postoperative infections . We hypothesized that preoperative skin cleansing with chlorhexidine-alcohol is more protective against infection than is povidone-iodine . METHODS We r and omly assigned adults undergoing clean-contaminated surgery in six hospitals to preoperative skin preparation with either chlorhexidine-alcohol scrub or povidone-iodine scrub and paint . The primary outcome was any surgical-site infection within 30 days after surgery . Secondary outcomes included individual types of surgical-site infections . RESULTS A total of 849 subjects ( 409 in the chlorhexidine-alcohol group and 440 in the povidone-iodine group ) qualified for the intention-to-treat analysis . The overall rate of surgical-site infection was significantly lower in the chlorhexidine-alcohol group than in the povidone-iodine group ( 9.5 % vs. 16.1 % ; P=0.004 ; relative risk , 0.59 ; 95 % confidence interval , 0.41 to 0.85 ) . Chlorhexidine-alcohol was significantly more protective than povidone-iodine against both superficial incisional infections ( 4.2 % vs. 8.6 % , P=0.008 ) and deep incisional infections ( 1 % vs. 3 % , P=0.05 ) but not against organ-space infections ( 4.4 % vs. 4.5 % ) . Similar results were observed in the per- protocol analysis of the 813 patients who remained in the study during the 30-day follow-up period . Adverse events were similar in the two study groups . CONCLUSIONS Preoperative cleansing of the patient 's skin with chlorhexidine-alcohol is superior to cleansing with povidone-iodine for preventing surgical-site infection after clean-contaminated surgery . ( Clinical Trials.gov number , NCT00290290 . OBJECTIVE To compare the effectiveness for prevention of  central venous and arterial catheter colonization  of 3 skin antisepsis with 1 of 3 antiseptic solutions : 10 % aqueous povidone iodine ( aqueous PI ) , 2 % aqueous chlorhexidine gluconate ( aqueous CG ) , and 0.5 % alcoholic chlorhexidine gluconate ( alcoholic CG ) . DESIGN Prospect i ve , r and omized controlled trial . SETTING Intensive care unit in a teaching hospital . METHODS Patients were r and omly assigned to 1 of the 3 skin antisepsis groups . The distal tips of catheters were semiquantitatively cultured when the catheters were no longer necessary or if there was a suspicion of catheter-related infection . Rates of catheter colonization , catheter-related sepsis , and catheter-related bacteremia were compared among the 3 groups . RESULTS A total of 631 catheters were included in the study ( 194 from the aqueous PI group , 211 from the aqueous CG group , and 226 from the alcoholic CG group ) . The incidence of catheter colonization was significantly lower in the alcoholic CG than in the aqueous PI group ( 14.2 % vs 24.7 % ; relative risk , 0.5 [ 95 % confidence interval , 0.3 - 0.8 ; P < .01 ] ) ; it was also significantly lower in the aqueous CG group than in the aqueous PI group ( 16.1 % vs 24.7 % ; relative risk , 0.6 [ 95 % confidence interval , 0.4 - 0.9 ; P = .03 ] ) . There were no significant differences between the aqueous CG and the alcoholic CG groups . Incidences of catheter-related bacteremia were similar for all 3 groups . The aqueous and alcoholic CG solutions were superior to the aqueous PI solution in preventing catheter colonization due to gram-positive bacteria . CONCLUSIONS The aqueous and alcoholic CG solutions for cutaneous antisepsis were similarly effective in preventing colonization of central venous catheters and arterial catheters . Both had significantly lower incidences of colonization than did the aqueous PI solution ; this effect seems to be related to the CG solutions ' more efficacious prevention of colonization with gram-positive bacteria Abstract Povidone-iodine and chlorhexidine surgical scrub and skin preparation solutions were assessed by comparing postoperative wound infection rates in a prospect i ve , r and omized study of 866 patients .  The frequency of wound infection overall , as agreed by two observers , was 14·8 per cent in the povidone-iodine group and 9·7 per cent in the chlorhexidine group ( P = 0·03 ) at the time of patients ' discharge from hospital . The difference between the compounds was not significant at a ‘ st and ard ' observation period of three to four days after operation . There were significantly fewer infections with chlorhexidine than with povidone-iodine in operations on the biliary tract and in ‘ clean ' non-abdominal operations , but there were more infections ( not significantly so ) with chlorhexidine than with povidoneiodine in large bowel surgery , other laparotomies and in operations on hernia , genitalia and varicose veins . The differences in bacterial isolates from wounds tended to follow the above patterns . We conclude that , on the evidence of this study , there is no overwhelming case for using one compound rather than the other as an all- purpose preparation and scrub This article review s the results and conclusions from four pivotal and two comparative clinical trials . The six r and omized , controlled , single-blinded , parallel-group clinical trials were conducted to determine which antiseptic is best for use as a patient preoperative skin preparation . The objective of these studies was to compare the immediate , persistent ( residual ) , and cumulative antimicrobial efficacy and safety of 2 % chlorhexidine gluconate ( CHG ) combined with 70 % isopropyl alcohol ( IPA ) ( ChloraPrep ) ; another combination CHG and IPA antiseptic ( CHG+IPA ) and 2 % aqueous CHG alone ; 4 % CHG ( Hibiclens ) alone ; 70 % isopropyl alcohol ( IPA ) alone ; and an iodine-containing solution , 10 % povidone-iodine ( Betadine ) alone as preoperative skin topical antiseptics for potential prevention of nosocomial infections BACKGROUND Although chlorhexidine-based solutions and alcohol-based povidone-iodine have been shown to be more efficient than aqueous povidone-iodine for skin disinfection at catheter insertion sites , their abilities to reduce catheter-related infection have never been compared . METHODS Consecutively scheduled central venous catheters inserted into jugular or subclavian veins were r and omly assigned to be disinfected with 5 % povidone-iodine in 70 % ethanol or with a combination of 0.25 % chlorhexidine gluconate , 0.025 % benzalkonium chloride , and 4 % benzylic alcohol . Solutions were used for skin disinfection before catheter insertion ( 2 consecutive 30-second applications separated by a period sufficiently long to allow for dryness ) and then as single applications during subsequent dressing changes ( every 72 hours , or earlier if soiled or wet ) . RESULTS Of 538 catheters r and omized , 481 ( 89.4 % ) produced evaluable culture results .  Compared with povidone-iodine , the chlorhexidine-based solution was associated with a 50 % decrease in the incidence of catheter colonization ( 11.6 % vs 22.2 % [ P = .002 ] ; incidence density , 9.7 vs 18.3 per 1000 catheter-days ) and with a trend toward lower rates of catheter-related bloodstream infection ( 1.7 % vs 4.2 % [ P = .09 ] ; incidence density , 1.4 vs 3.4 per 1000 catheter-days ) . Independent risk factors for catheter colonization were catheter insertion into the jugular vein ( adjusted relative risk , 2.01 ; 95 % confidence interval , 1.24 - 3.24 ) and use of povidone-iodine ( adjusted relative risk , 1.87 ; 95 % confidence interval , 1.18 - 2.96 ) . CONCLUSION Chlorhexidine-based solutions should be considered as a replacement for povidone-iodine ( including alcohol-based ) formulations in efforts to prevent catheter-related infection BACKGROUND Previous studies have demonstrated higher infection rates following orthopaedic procedures on the foot and ankle as compared with procedures involving other areas of the body . Previous studies also have documented the 
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RESULTS In all three application areas and for all outcomes , we found good evidence favouring chlorhexidine-alcohol over aqueous competitors , but not over competitors combined with alcohols .
For blood cultures and surgery , we found no evidence supporting chlorhexidine alone .
For catheters , we found evidence in support of chlorhexidine alone for preventing catheter colonisation , but not for preventing bloodstream infection .
Perceived efficacy of chlorhexidine is often in fact based on evidence for the efficacy of the chlorhexidine-alcohol combination .