13.1. Evidence for surgical hand preparation
Historically, Joseph Lister (1827–1912) demonstrated the effect of disinfection on the reduction of surgical site infections (SSIs).506 At that time, surgical gloves were not yet available, thereby making appropriate disinfection of the surgical site of the patient and hand antisepsis by the surgeon even more imperative.507 During the 19th century, surgical hand preparation consisted of washing the hands with antimicrobial soap and warm water, frequently with the use of a brush.508 In 1894, three steps were suggested: 1) wash hands with hot water, medicated soap, and a brush for 5 minutes; 2) apply 90% ethanol for 3–5 minutes with a brush; and 3) rinse the hands with an “aseptic liquid”.508 In 1939, Price suggested a 7-minute handwash with soap, water, and a brush, followed by 70% ethanol for 3 minutes after drying the hands with a towel.63 In the second half of the 20th century, the recommended time for surgical hand preparation decreased from >10 minutes to 5 minutes.509–512 Even today, 5-minute protocols are common.197 A comparison of different countries showed almost as many protocols as listed countries.513
The introduction of sterile gloves does not render surgical hand preparation unnecessary. Sterile gloves contribute to preventing surgical site contamination514 and reduce the risk of bloodborne pathogen transmission from patients to the surgical team.515 However, 18% (range: 5–82%) of gloves have tiny punctures after surgery, and more than 80% of cases go unnoticed by the surgeon. After two hours of surgery, 35% of all gloves demonstrate puncture, thus allowing water (hence also body fluids) to penetrate the gloves without using pressure516 (see Part I, Section 23.1). A recent trial demonstrated that punctured gloves double the risk of SSIs.517 Double gloving decreases the risk of puncture during surgery, but punctures are still observed in 4% of cases after the procedure.518,519 In addition, even unused gloves do not fully prevent bacterial contamination of hands.520 Several reported outbreaks have been traced to contaminated hands from the surgical team despite wearing sterile gloves.71,154,162,521–523
Koiwai and colleagues detected the same strain of coagulase-negative staphylococci (CoNS) from the bare fingers of a cardiac surgeon and from a patient with postoperative endocarditis with a matching strain.522 A similar, more recent outbreak with CoNS and endocarditis was observed by Boyce and colleagues, strain identity being confirmed by molecular methods.162 A cardiac surgeon with onychomycosis became the source of an outbreak of SSIs due to P. aeruginosa, possibly facilitated by not routinely practising double gloving.523 One outbreak of SSIs even occurred when surgeons who normally used an antiseptic surgical scrub preparation switched to a nonantimicrobial product.524
Despite a large body of indirect evidence for the need of surgical hand antisepsis, its requirement before surgical interventions has never been proven by a randomized, controlled clinical trial.525 Most likely, such a study will never be performed again nor be acceptable to an ethics committee. A randomized clinical trial comparing an alcohol-based handrub versus a chlorhexidine hand scrub failed to demonstrate a reduction of SSIs, despite considerably better in vitro activity of the alcohol-based formulation.197 Therefore, even considerable improvements in antimicrobial activity in surgical hand hygiene formulations are unlikely to lead to significant reductions of SSIs. These infections are the result of multiple risk factors related to the patient, the surgeon, and the health-care environment, and the reduction of only one single risk factor will have a limited influence on the overall outcome.
In addition to protecting the patients, gloves reduce the risk for the HCW to be exposed to bloodborne pathogens. In orthopaedic surgery, double gloving has been a common practice that significantly reduces, but does not eliminate, the risk of cross-transmission after glove punctures during surgery.526
13.2. Objective of surgical hand preparation
Surgical hand preparation should reduce the release of skin bacteria from the hands of the surgical team for the duration of the procedure in case of an unnoticed puncture of the surgical glove releasing bacteria to the open wound.527 In contrast to the hygienic handwash or handrub, surgical hand preparation must eliminate the transient and reduce the resident flora.484,528,529 It should also inhibit growth of bacteria under the gloved hand. Rapid multiplication of skin bacteria occurs under surgical gloves if hands are washed with a non-antimicrobial soap, whereas it occurs more slowly following preoperative scrubbing with a medicated soap. The skin flora, mainly coagulase-negative staphylococci, Propionibacterium spp., and Corynebacteria spp., are rarely responsible for SSI, but in the presence of a foreign body or necrotic tissue even inocula as low as 100 CFU can trigger such infection.530 The virulence of the microorganisms, extent of microbial exposure, and host defence mechanisms are key factors in the pathogenesis of postoperative infection, risk factors that are largely beyond the influence of the surgical team. Therefore, products for surgical hand preparation must eliminate the transient and significantly reduce the resident flora at the beginning of an operation and maintain the microbial release from the hands below baseline until the end of the procedure.
The spectrum of antimicrobial activity for surgical hand preparation should be as broad as possible against bacteria and fungi.529,531 Viruses are rarely involved in SSI and are not part of test procedures for licensing in any country. Similarly, activity against spore-producing bacteria is not part of international testing procedures.
13.3. Selection of products for surgical hand preparation
The lack of appropriate, conclusive clinical trials precludes uniformly acceptable criteria. In vitro and in vivo trials with healthy volunteers outside the operating theatre are the best evidence currently available. In the USA, antiseptic preparations intended for use as surgical hand preparation (based on the FDA TFM of 17 June 1994)198 are evaluated for their ability to reduce the number of bacteria released from hands: a) immediately after scrubbing; b) after wearing surgical gloves for 6 hours (persistent activity); and c) after multiple applications over 5 days (cumulative activity). Immediate and persistent activities are considered the most important. Guidelines in the USA recommend that agents used for surgical hand preparation should significantly reduce microorganisms on intact skin, contain a non-irritating antimicrobial preparation, have broad-spectrum activity, and be fast-acting and persistent (see Part I, Section 10).532 In Europe, all products must be at least as efficacious as a reference surgical rub with n-propanol, as outlined in the European Norm EN 12791. In contrast to the USA’ guidelines, only the immediate effect after the hand hygiene procedure and the level of regrowth after 3 hours under gloved hands are measured. The cumulative effect over 5 days is not a requirement of EN 12791.
Most guidelines prohibit any jewellery or watches on the hands of the surgical team ().58,529,533 Artificial fingernails are an important risk factor, as they are associated with changes of the normal flora and impede proper hand hygiene.154,529 Therefore, they should be prohibited for the surgical team or in the operating theatre.154,529,534
Steps before starting surgical hand preparation.
13.4. Surgical hand antisepsis using medicated soap
The different active compounds included in commercially available handrub formulations are described in Part I, Section 11. The most commonly used products for surgical hand antisepsis are chlorhexidine or povidone-iodine-containing soaps. The most active agents (in order of decreasing activity) are chlorhexidine gluconate, iodophors, triclosan, and plain soap.282,356,378,529,535–537 Triclosan-containing products have also been tested for surgical hand antisepsis, but triclosan is mainly bacteriostatic, inactive against P. aeruginosa, and has been associated with water pollution in lakes.538,539 Hexachlorophene has been banned worldwide because of its high rate of dermal absorption and subsequent toxic effects.70,366 Application of chlorhexidine or povidone-iodine result in similar initial reductions of bacterial counts (70–80%), reductions that achieves 99% after repeated application. Rapid regrowth occurs after application of povidone-iodine, but not after use of chlorhexidine.540 Hexachlorophene and triclosan detergents show a lower immediate reduction, but a good residual effect. These agents are no longer commonly used in operating rooms because other products such as chlorhexidine or povidone-iodine provide similar efficacy at lower levels of toxicity, faster mode of action, or broader spectrum of activity. Despite both in vitro and in vivo studies demonstrating that it is less efficacious than chlorhexidine, povidone-iodine remains one of the widely-used products for surgical hand antisepsis, induces more allergic reactions, and does not show similar residual effects.271,463 At the end of a surgical intervention, iodophor-treated hands can have even more microorganisms than before surgical scrubbing. Warm water makes antiseptics and soap work more effectively, while very hot water removes more of the protective fatty acids from the skin. Therefore, washing with hot water should be avoided. The application technique is probably less prone to errors compared with handrubbing () as all parts of the hands and forearms get wet under the tap/faucet. In contrast, all parts of the hands and forearms must actively be put in contact with the alcohol-based compound during handrubbing (see below).
Protocol for surgical scrub with a medicated soap.
13.4.1. Required time for the procedure
Hingst and colleagues compared hand bacterial counts after 3-minute and 5-minute scrubs with seven different formulations.378 Results showed that the 3-minute scrub could be as effective as the 5-minute scrub, depending on the formula of the scrub agent. Immediate and postoperative hand bacterial counts after 5-minute and 10-minute scrubs with 4% chlorhexidine gluconate were compared by O’Farrell and colleagues before total hip arthroplasty procedures.512 The 10-minute scrub reduced the immediate colony count more than the 5-minute scrub. The postoperative mean log CFU count was slightly higher for the 5-minute scrub than for the 10-minute scrub; however, the difference between post-scrub and postoperative mean CFU counts was higher for the 10-minute scrub than the 5-minute scrub in longer (>90 minutes) procedures. The study recommended a 5-minute scrub before total hip arthroplasty.
A study by O’Shaughnessy and colleagues used 4% chlorhexidine gluconate in scrubs of 2, 4, and 6-minutes duration. A reduction in post-scrub bacterial counts was found in all three groups. Scrubbing for longer than 2 minutes did not confer any advantage. This study recommended a 4-minute scrub for the surgical team’s first procedure and a 2-minute scrub for subsequent procedures.541 Bacterial counts on hands after 2-minute and 3-minute scrubs with 4% chlorhexidine gluconate were compared.542 A statistically significant difference in mean CFU counts was found between groups with the higher mean log reduction in the 2-minute group. The investigators recommended a 2-minute procedure. Poon and colleagues applied different scrub techniques with a 10% povidone-iodine formulation.543 Investigators found that a 30-second handwash can be as effective as a 20-minute contact with an antiseptic in reducing bacterial flora and that vigorous friction scrub is not necessarily advantageous.
13.4.2. Use of brushes
Almost all studies discourage the use of brushes. Early in the 1980s, Mitchell and colleagues suggested a brushless surgical hand scrub.544 Scrubbing with a disposable sponge or combination sponge-brush has been shown to reduce bacterial counts on the hands as effectively as scrubbing with a brush.511,545,546 Recently, even a randomized, controlled clinical trial failed to demonstrate an additional antimicrobial effect by using a brush.547 It is conceivable that a brush may be beneficial on visibly dirty hands before entering the operating room. Members of the surgical team who have contaminated their hands before entering the hospital may wish to use a sponge or brush to render their hands visibly clean before entering the operating room area.
13.4.3. Drying of hands
Sterile cloth towels are most frequently used in operating theatres to dry wet hands after surgical hand antisepsis. Several methods of drying have been tested without significant differences between techniques.256
13.4.4. Side-effects of surgical hand scrub
Skin irritation and dermatitis are more frequently observed after surgical hand scrub with chlorhexidine than after use of surgical hand antisepsis with an alcohol-based hand rinse.197 Overall, skin dermatitis is more frequently associated with hand antisepsis using a medicated soap than with an alcohol-based handrub.548 Boyce and colleagues quantified the epidermal water content of the dorsal surface of nurses’ hands by measuring electrical capacitance of the skin. The water content decreased significantly during the washing phase compared with the alcohol-based handrub-in phase.264 Most data have been generated outside the operating room, but it is conceivable that these results apply for surgical hand antisepsis as well.549
13.4.5. Potential for recontamination
Surgical hand antisepsis with medicated soap requires clean water to rinse the hands after application of the medicated soap. However, Pseudomonas spp., specifically P. aeruginosa, are frequently isolated from taps/faucets in hospitals.550. Taps are common sources of P. aeruginosa and other Gram-negative bacteria and have even been linked to infections in multiple settings, including ICUs.551 It is therefore prudent to remove tap aerators from sinks designated for surgical hand antisepsis.551–553 Even automated sensor-operated taps were linked to P. aeruginosa contamination.554 Outbreaks or cases clearly linked to contaminated hands of surgeons after proper surgical hand scrub have not yet been documented. However, outbreaks with P.aeruginosa were reported as traced to members of the surgical team suffering from onychomycosis,154,523 but a link to contaminated tap water has never been established. In countries lacking continuous monitoring of drinking-water and improper tap maintenance, recontamination may be a real risk even after correct surgical hand scrub. Of note, one surgical hand preparation episode with traditional agents uses approximately 20 litres of warm water, or 60 litres and more for the entire surgical team.555 This is an important issue worldwide, particularly in countries with a limited safe water supply.
13.5. Surgical hand preparation with alcohol-based handrubs
Several alcohol-based handrubs have been licensed for the commercial market,531,556,557 frequently with additional, long-acting compounds (e.g. chlorhexidine gluconate or quaternary ammonium compounds) limiting regrowth of bacteria on the gloved hand,377,529,558–561 The antimicrobial efficacy of alcohol-based formulations is superior to that of all other currently available methods of preoperative surgical hand preparation. Numerous studies have demonstrated that formulations containing 60–95% alcohol alone, or 50–95% when combined with small amounts of a QAC, hexachlorophene or chlorhexidine gluconate, reduce bacterial counts on the skin immediately post-scrub more effectively than do other agents.
The WHO-recommended handrub formulations were tested by two independent reference laboratories in different European countries to assess their suitability for use for surgical hand preparation. Although formulation I did not pass the test in both laboratories and formulation II in only one of them, the expert group is, nevertheless, of the opinion that the microbicidal activity of surgical antisepsis is still an ongoing issue for research as due to the lack of epidemiological data there is no indication that the efficacy of n-propanol (propan-1-ol) 60 % v/v as a reference in EN 12791 finds a clinical correlate. It is the consensus opinion of the WHO expert group that the choice of n-propanol is inappropriate as the reference alcohol for the validation process because of its safety profile and the lack of evidence-based studies related to its potential harmfulness for humans. Indeed, only a few formulations worldwide have incorporated n-propanol for hand antisepsis.
Considering that other properties of the WHO recommended formulations, such as their excellent tolerability, good acceptance by HCWs and low cost are of high importance for a sustained clinical effect, the above results are considered acceptable and it is the consensus opinion of the WHO expert group that the two formulations can be used for surgical hand preparation. Institutions opting to use the WHO-recommended formulations for surgical hand preparation should ensure that a minimum of three applications are used, if not more, for a period of 3 to 5 minutes. For surgical procedures of more than a two hours’ duration, ideally surgeons should practise a second handrub of approximately 1 minute, even though more research is needed on this aspect.
Hand-care products should not decrease the antimicrobial activity of the handrub. A study by Heeg562 failed to demonstrate such an interaction, but manufacturers of a handrub should provide good evidence for the absence of interaction.563
It is not necessary to wash hands before handrub unless hands are visibly soiled or dirty.562,564 The hands of the surgical team should be clean upon entering the operating theatre by washing with a non-medicated soap (). While this handwash may eliminate any risk of contamination with bacterial spores, experimental and epidemiological data failed to demonstrate an additional effect of washing hands before applying handrub in the overall reduction of the resident skin flora.531 The activity of the handrub formulation may even be impaired if hands are not completely dried before applying the handrub or by the washing phase itself.562,564,565 A simple handwash with soap and water before entering the operating theatre area is highly recommended to eliminate any risk of colonization with bacterial spores.420 Non-medicated soaps are sufficient,566 and the procedure is necessary only upon entering the operating theatre: repeating handrubbing without prior handwash or scrub is recommended before switching to the next procedure.
13.5.1. Technique for the application of surgical hand preparation using alcohol-based handrub
The application technique has not been standardized throughout the world. The WHO approach for surgical hand preparation requires the six basic steps for the hands as for hygienic hand antisepsis, but requires additional steps for rubbing the forearms (). This simple procedure appears not to require training, though two studies provide evidence that training significantly improves bacterial killing.531,567 The hands should be wet from the alcohol-based rub during the whole procedure, which requires approximately 15 ml depending on the size of the hands. One study demonstrated that keeping the hands wet with the rub is more important than the volume used.568 The size of the hands and forearms ultimately determines the volume required to keep the skin area wet during the entire time of the handrub. Once the forearms and hands have been treated with an emphasis on the forearms – usually for approximately 1 minute – the second part of the surgical handrub should focus on the hands, following the identical technique as outlined for the hygienic handrub. The hands should be kept above the elbows during this step.
Surgical hand preparation technique with an alcohol-based handrub formulation.
13.5.2. Required time for the procedure
For many years, surgical staff frequently scrubbed their hands for 10 minutes preoperatively, which frequently led to skin damage. Several studies have demonstrated that scrubbing for 5 minutes reduces bacterial counts as effectively as a 10-minute scrub.284,511,512 In other studies, scrubbing for 2 or 3 minutes reduced bacterial counts to acceptable levels.378,380,460,529,541,542 Surgical hand antisepsis using an alcohol-based handrub required 3 minutes, following the reference method outlined in EN 12791. Very recently, even 90 seconds of rub have been shown to be equivalent to a 3-minute rub with a product containing a mixture of iso- and n-propanol and mecetronium etilsulfate557 when tested with healthy volunteers in an in vivo experiment. These results were corroborated in a similar study performed under clinical conditions with 32 surgeons.569
Alcohol-based hand gels should not be used unless they pass the test EN 12791 or an equivalent standard, e.g. FDA TFM 1994, required for handrub formulations.533 Many of the currently available gels for hygienic handrub do not meet the European standard EN 1500.203 The technique to apply the alcohol-based handrub defined by EN 1500 matches the one defined by EN 12791. The latter requires an additional rub of the forearms that is not required for the hygienic handrub (). At least one gel on the market has been tested and introduced in a hospital for hygienic hand antisepsis and surgical hand preparation that meets EN 12791,570 and several gels meet the FDA TFM standard.482 As mentioned above, the minimal killing is not defined and, therefore, the interpretation of the effectiveness remains elusive.
In summary, the time required for surgical alcohol-based handrubbing depends on the compound used. Most commercially available products recommend a 3-minute exposure, although the application time may be longer for some formulations, but can be shortened to 1.5 minutes for a few of them. The manufacturer of the product must provide recommendations as to how long the product must be applied. Manufacturer’s recommendations should be based on in vivo evidence at least, considering that clinical effectiveness testing is unrealistic.
13.6. Surgical handscrub with medicated soap or surgical hand preparation with alcohol-based formulations
Both methods are suitable for the prevention of SSIs. However, although medicated soaps have been and are still used by many surgical teams worldwide for presurgical hand preparation, it is important to note that the antibacterial efficacy of products containing high concentrations of alcohol by far surpasses that of any medicated soap presently available (see Part I, section 13.5). In addition, the initial reduction of the resident skin flora is so rapid and effective that bacterial regrowth to baseline on the gloved hand takes more than six hours. 227 This makes the demand for a sustained effect of a product superfluous. For this reason, preference should be given to alcohol-based products. Furthermore, several factors including rapid action, time savings, less side-effects, and no risk of recontamination by rinsing hands with water, clearly favour the use of presurgical handrubbing. Nevertheless, some surgeons consider the time taken for surgical handscrub as a ritual for the preparation of the intervention571 and a switch from handscrub to handrub must be prepared with caution. In countries with limited resources, particularly when the availability, quantity or quality of water is doubtful, the current panel of experts clearly favours the use of alcohol-based handrub for presurgical hand preparation also for this reason.
