Hand-Rubbing With an Aqueous Alcoholic Solution vs Traditional Surgical Hand-Scrubbing and 30-Day Surgical Site Infection Rates: A Randomized Equivalence Study

Context Surgical site infections prolong hospital stays, are among the leadingnosocomial causes of morbidity, and a source of excess medical costs. Clinicalstudies comparing the risk of nosocomial infection after different hand antisepsisprotocols are scarce.

Objective To compare the effectiveness of hand-cleansing protocols in preventingsurgical site infections during routine surgical practice.

Design Randomized equivalence trial.

Setting Six surgical services from teaching and nonteaching hospitals in France.

Patients A total of 4387 consecutive patients who underwent clean and clean-contaminatedsurgery between January 1, 2000, and May 1, 2001.

Interventions Surgical services used 2 hand-cleansing methods alternately every othermonth: a hand-rubbing protocol with 75% aqueous alcoholic solution containingpropanol-1, propanol-2, and mecetronium etilsulfate; and a hand-scrubbingprotocol with antiseptic preparation containing 4% povidone iodine or 4% chlorhexidinegluconate.

Main Outcome Measures Thirty-day surgical site infection rates were the primary end point;operating department teams' tolerance of and compliance with hand antisepsiswere secondary end points.

Results The 2 protocols were comparable in regard to surgical site infectionrisk factors. Surgical site infection rates were 55 of 2252 (2.44%) in thehand-rubbing protocol and 53 of 2135 (2.48%) in the hand-scrubbing protocol,for a difference of 0.04% (95% confidence interval, −0.88% to 0.96%).Based on subsets of personnel, compliance with the recommended duration ofhand antisepsis was better in the hand-rubbing protocol of the study comparedwith the hand-scrubbing protocol (44% vs 28%, respectively; P = .008), as was tolerance, with less skin dryness and less skin irritationafter aqueous solution use.

Conclusions Hand-rubbing with aqueous alcoholic solution, preceded by a 1-minutenonantiseptic hand wash before each surgeon's first procedure of the day andbefore any other procedure if the hands were soiled, was as effective as traditionalhand-scrubbing with antiseptic soap in preventing surgical site infections.The hand-rubbing protocol was better tolerated by the surgical teams and improvedcompliance with hygiene guidelines. Hand-rubbing with liquid aqueous alcoholicsolution can thus be safely used as an alternative to traditional surgicalhand-scrubbing.

Surgical site infections (SSI) prolong hospital stays¹;they are also among the leading nosocomial causes of morbidity²and a source of excess medical costs.³ Sterilegloves contribute to preventing surgical wound contamination,⁴but some are permeable to bacteria and all can be damaged during use. Effectivehand antisepsis thus remains crucial. Guidelines on hand and forearm antisepsisfor operating department staff⁵ aim at removingtransient microorganisms and reducing the resident flora (by at least 2-log).

In France, 2 protocols are recommended for surgical hand preparation:5 minutes of hand-scrubbing with antiseptic soap; and an optional 1-minutehand wash with nonantiseptic soap and tap water, followed by 5 minutes ofhand-rubbing with a liquid aqueous alcoholic solution (AAS) alone. In otherEuropean countries, only 3 minutes of hand-rubbing with AAS are recommended.Many reports suggest that AAS has better and more sustained antimicrobialactivity than traditional scrubs.^6-11For example, Hobson et al¹¹ compared hand antimicrobialcount after either 3 minutes of hand-scrubbing with solutions containing 7.5%povidone iodine and 4% chlorhexidine gluconate or 3 minutes of hand-rubbingwith an AAS. Mean logarithmic reduction of colony forming units (CFU) frombaseline was significantly higher in the AAS protocol when compared with povidoneiodine or chlorhexidine gluconate after 1 minute (2.90 log₁₀ vs1.20 log₁₀ and 1.68 log₁₀ of CFU reduction from baseline),3 hours (1.58 log₁₀ vs 0.71 log₁₀ and 1.08 log₁₀ of CFU reduction from baseline) and 6 hours (1.94 log₁₀vs –0.21 log₁₀ and 0.86 log₁₀ of CFU reductionfrom baseline) at day 1 and day 2. However, these investigations involvedhealthy volunteers or short study periods, with hand microorganism countsas the primary end point. Poor compliance and the risk of dermatitis werenot taken into account. Because of the need for a very large population sample,together with the existence of numerous confounding factors and prohibitivecosts, clinical studies comparing the risk of nosocomial infection after differenthand antisepsis protocols are scarce.^5,9

To confirm the validity of current recommendations for hand antisepsisbefore surgery, we conducted a randomized equivalence study comparing hand-scrubbingand hand-rubbing protocols with a multiple service crossover experimentaldesign. The aim was to demonstrate the equivalence of the 2 protocols in termsof SSI rates.

Six surgical services in France were invited to participate in thisstudy and all accepted. They consisted of 3 surgical services of a teachinghospital (Côte de Nacre University Hospital Centre, Caen) and the surgicalservices of 3 nonteaching hospitals (François Baclesse Centre, Caen;General Hospital, Colmar; General Hospital, Pont-Audemer). A 2-month feasibilitystudy was first conducted in a single surgical service, during which trainingrequirements were determined; the surgical team switched readily from traditionalhand-scrubbing to hand-rubbing with AAS. Surgeons from the 6 candidate centerswere then invited to discuss the project. The clinical trial started January1, 2000, and lasted 16 months (May 1, 2001). The following end points wereused: nosocomial SSI rates (main end point), compliance by the surgical teams,and tolerance of the 2 hand antisepsis protocols by the surgical teams inreal world conditions. The first protocol to be used in each surgical servicewas chosen randomly. Each participating surgical service was assigned a 2-digitrandom number by using a random number table. Surgical services correspondingto the 3 higher numbers were assigned to hand-rubbing with AAS and the remaining3 services were assigned to traditional hand-scrubbing. The alternative antisepticproduct was systematically removed from the services during each period. Atthe end of each month, the antiseptic products were switched in a multipleservice crossover design.

Diagnosis for SSI was standardized in accordance with the Centers forDisease Control and Prevention (CDC) definitions for nosocomial infection.¹² For the purpose of this study, however, SSI surveillancelasted 30 days regardless of prosthesis implantation. It should be noted thatour hygiene department has been involved in SSI surveillance for many years.¹³

In-hospital SSIs were prospectively diagnosed by a surgeon, infectiousdisease specialist, or hygiene specialist on a standard data-collection form.Postdischarge surveillance was based on chart review of visits and telephonecontacts with the surgeons. If data at 30 days were unavailable, the patientwas contacted by telephone and asked to answer a brief questionnaire on feverand other potential symptoms of SSI, together with antibiotic use and visitsto an emergency department or to another physician, who was then contactedto confirm the SSI.

According to CDC guidelines, all SSIs had to be confirmed by the surgeonor the physician in charge of the patient. Thus, observers of the clinicaloutcome could not be blinded to the hand antisepsis protocol. For possiblepostdischarge SSIs reported by the patient only, a data validation for SSIsaccording to CDC guidelines was performed by investigators who were blindedto the protocol used by surgeons prior to surgical procedure.

All consecutive patients treated in the 6 participating surgical serviceswere screened for SSI. Because bacteria on operating department personnelhands are more likely to affect the outcome in clean and clean-contaminatedsurgical wounds (classified according to Altemeier et al¹⁴),our study group decided to exclude from analysis patients in contaminatedor dirty procedure groups, when designing this study. Patients undergoinga second operation less than 15 days after the first were also excluded, becausethis is an independent risk factor for SSI.

The first 2 months after randomization of the services, investigatorschecked if the protocols were correctly performed. Therefore, because introductionof a new protocol and feedback can influence short-term surgical personnelbehavior, compliance observations for the hand antisepsis protocol startedat month 3 and continued until month 16. Twice as many observations were performedin the new hand-rubbing protocol compared with the traditional hand-scrubbingprotocol. Compliance observers did not belong to the operating departmentteam but were usually present in the surgical suite. To avoid a Hawthorneeffect, the surgical teams were not informed of the timing of the evaluations.Only the first hand antisepsis of the day was observed in the 2 study protocols.

In the 3 participating surgical services of our teaching hospital (Côtede Nacre University Hospital Centre), the surgical personnel (77 subjects)were asked to estimate the effect of the 2 protocols on their skin. We used2 10-cm visual analog scales, at month 0 and after 3 crossovers; 0 cm representingabsence of any tolerance problem and 10 cm representing maximal dryness withchapped hands and desquamation or maximal irritation with erythema, burningsensation, and abrasion.

The standard surgical scrubbing antisepsis technique was as definedin CDC guidelines. In particular, at least 5 minutes of systematic hand-scrubbingwas required with a sterile sponge and brush. Hand-scrubbing with antisepticsolutions containing 4% povidone iodine (Betadine, Asta Medica, Merignac,France) or 4% chlorhexidine gluconate (Hibiscrub, AstraZeneca, Rueil-Malmaison,France) had been used for many years by the surgical teams and was thus chosenas the control protocol for this study.

Hand-rubbing involved a 75% AAS containing propanol-1, propanol-2, andmecetronium etilsulfate (Stérillium, Rivadis Laboratories, Thouard,France). We chose this product because it was the only AAS licensed for surgicalantisepsis in France. Prior to the first procedure of the day, or if the handswere visibly soiled, the surgical team was instructed to use a nonantisepticsoap (Savon Codex, Rivadis Laboratories, Thouard, France) for a 1-minute handwash, including subungual space cleaning with a brush. The hands and forearmswere then rinsed with nonsterile tap water and wiped carefully with nonsterilepaper. The user was instructed to take enough AAS to fully cover the handsand forearms (at least 5 mL, which represents at least 4 pump strokes), andto apply it twice for 2 minutes 30 seconds (for a total of 5 minutes) withoutdrying. As recommended by the manufacturer, users were also instructed torub their hands with AAS for 30 seconds when changing gloves. The hand-rubbingtechnique was based on the European Norm 1500 from the Association Françaisede Normalisation.

The study was designed to demonstrate the equivalence of hand-scrubbingand hand-rubbing in preventing SSI (primary end point). We chose an SSI rateof 4% in the control group, a maximal difference between the protocols of2% (considered as clinically relevant), a real difference between the 2 protocolsof 0%, a type I error α risk of .05, and 90% power when calculatingthe number of patients required. On this basis, at least 4158 patients hadto be enrolled.¹⁵ We performed an as-treatedanalysis as well as a conservative intent-to-treat analysis computing missingvalue equals SSI in the new protocol and missing value equals no SSI in thecontrol group. The 2 protocols were considered equivalent if the 95% confidenceinterval (CI) of the SSI rate difference, calculated according to the Wallensteinmethod,¹⁶ was within the limits of –2%to +2% and contained the bound zero in both analyses, the as-treated as wellas in the conservative intent-to-treat. The level of significance for equivalencewas given by the highest P value related to the lowest χ² value of the continuity-corrected 1-sided test described by Dunnettand Gent.¹⁷ Compliance and tolerance (secondaryend points) were compared using the Fischer exact test for qualitative dataand Mann-Whitney test or a matched t test for quantitativedata as appropriate (2-sided P values). After checkingfor the absence of interaction, observations regarding compliance with andtolerance of hand hygiene protocols from different surgical services and fromdifferent quarters of the study were merged. P<.05was considered statistically significant. We used EPI-INFO version 6.04dfr(EPI-INFO, CDC, Atlanta, Ga) for data collection and EPI-INFO and SAS version6.12 (SAS Institute Inc, Cary, NC) for data analysis.

During the study period (Figure 1),4823 consecutive patients underwent surgery. Among these, 385 patients underwentcontaminated or dirty-contaminated surgery, and 51 were lost to follow-upat 30 days (17 in the hand-rubbing group). The remaining 4387 patients (68.5%of whom underwent clean surgery) were considered for analysis. The characteristicsof these patients are shown in Table 1,according to the type of protocol. There were 446 gynecological operations(33%), 383 cesarean deliveries (28%), and 356 breast operations (26%) (n =1359). Thyroidectomy was the most frequent otolaryngology procedure (n = 346).Urological indications (n = 540) comprised 384 (71%) bladder or urethral operationsand 85 (16%) kidney operations. Orthopedic procedures (n = 746) comprised290 (39%) osteosyntheses and 147 (20%) prosthesis insertions.

The surveillance system identified 99 in-hospital and 9 postdischargeSSIs. The global SSI rate 30 days after surgery was 2.46% (95% CI, 1.81%-3.11%).The SSI rates for clean and clean-contaminated surgery were 2.03% (95% CI,1.33%-2.73%) and 3.40% (95% CI, 2.07%-4.73%), respectively. In the hand-scrubbingprotocol, 21 SSIs were superficial, 19 deep, and 8 organ-space (5 unknown).In the hand-rubbing protocol, 24 SSIs were superficial, 15 deep, and 7 organ-space(9 unknown). The distribution of these categories of SSI did not differ betweenthe 2 protocols.

There were 53 of 2135 SSIs (2.48%) in the hand-scrubbing protocol and55 of 2252 (2.44%) in the hand-rubbing protocol (Table 2). The difference between the SSI rate with hand-scrubbingand the SSI rate with hand-rubbing with AAS was 0.04% (as treated 95% CI, −0.88%to 0.96%). In an intention-to-treat analysis, considering that all the 17patients lost to follow-up in the hand-rubbing group had an SSI and none ofthe 34 patients lost to follow-up in the hand-scrubbing group had an SSI (maximalbias), the rate difference would have been –0.69% (95% CI, −1.67%to 0.29%). The equivalence of the 2 protocols in preventing SSI was thus accepted.

During the study period, 278 individual compliance assessments weremade of the operating teams (174 in the hand-rubbing group), correspondingwith 160 surgical procedures (102 in the hand-rubbing group). On average,the first hand-cleansing protocol of the day (Table 3), excluding the simple nonantiseptic hand wash prior tohand-rubbing, lasted significantly longer in the hand-rubbing group than inthe hand-scrubbing group (mean [SD], 313 [80] seconds vs 287 [75] seconds; P = .01). Scrub nurses complied better with the recommendedduration of hand antisepsis than did surgeons and assistants (56% vs 33%; P<.001). Compliance with the recommended duration ofhand hygiene was poor in both protocols but was significantly better in thehand-rubbing group than in the hand-scrubbing group (44% vs 28%, respectively; P = .008).

In the hand-rubbing group, 6 of 102 (6%) of first procedures did notinclude a simple nonantiseptic hand wash before hand-rubbing (4 in abdominalsurgery, 2 in gynecology). During the days nonantiseptic hand washing priorto the first handrub with AAS was not performed by the surgical personnelin the hand-rubbing protocol, 2 SSIs occurred for a total of 34 procedures(5.9%) compared with 2 SSIs for 56 procedures (3.6%) when the nonantiseptichand washing was performed in the same services. Glove changes occurred during32 of the 102 observed procedures in the hand-rubbing protocol; the recommended30-second AAS rub before a glove change was complied with in 16 of these 32cases, not complied with in 10 cases, and 6 were unknown.

A total of 77 operating department staff members were assessed for skintolerance at entry to the study and after the first 3 crossovers. Based onthe visual analog scales scores, skin dryness decreased by 0.9 cm (95% CI,0.5-1.2) after the hand-rubbing periods and increased by 0.4 cm (95% CI, –0.1to 1.2) after the hand-scrubbing periods (P = .046).Similarly, skin irritation decreased by 1.5 cm (95% CI, 1.1-1.9) after thehand-rubbing periods and increased by 0.4 cm (95% CI, 0.2-0.6) after the hand-scrubbingperiods (P = .03). One scrub nurse reported handand eye irritation (swelling) when using AAS for hand-rubbing.

To our knowledge, this study is the first randomized trial to comparehand-rubbing with alcohol-based solution and traditional hand-scrubbing inthe routine surgical setting, with the 30-day SSI rate as the primary endpoint. The hand-rubbing with AAS was equivalent to traditional hand-scrubbingin preventing SSI after clean and clean-contaminated surgery. In addition,hand-rubbing with AAS improved the tolerance of and compliance with hand antisepsisprotocols, as evaluated for 4 and 14 months, respectively.

This study involved an unselected population of patients undergoingroutine surgery in teaching and nonteaching hospitals. The baseline SSI ratesfor abdominal surgery procedures only, with routine 3-month per year surveillancemethods were 45 of 912 (4.9%) on average during 1997-2000.¹³The SSI rates we observed in this study are consistent with those reportedelsewhere.^18,19 In a cohort of59 352 patients, Haley et al¹⁸ found anSSI rate of 2.9% and 3.9% in clean and clean-contaminated class of procedures,respectively. Olson and Lee¹⁹ reported an infectionrate of 1.4% in clean and 2.8% in clean-contaminated procedures in 40 915patients. However, we observed a very low proportion of postdischarge SSIs(8.3%) compared with recent studies. The percentages of SSIs occurring afterhospital discharge vary from 13.6% to 84.0% according to studies^20-22;thus, we cannot exclude that possible SSIs were not validated in the absenceof evidence, although they were real.

Any direct comparison between reported studies would be hazardous, asthey differ in several respects, such as the SSI rate surveillance methods,the study period, and the characteristics of the study population. In ourstudy, differences in the characteristics of the patients and surgical personnelin the 2 protocols were minimized by the randomized service crossover experimentaldesign.

Infection control epidemiology has clearly demonstrated that bacteriaresponsible for SSI can be shed from the surgical team's hands, despite standardantisepsis.^23-25Alcohol-based hand disinfection has previously been shown to reduce nosocomialinfection rates and to improve compliance with hand hygiene rules when implementedthroughout a hospital, particularly at the bedside in medical wards,²⁶ although other studies are less favorable.^27,28 An 8-month prospective study conductedin 3 intensive care units showed that the rate of nosocomial infections wassignificantly higher after alcohol-based vs scrub-based hand hygiene, possiblydue to poor compliance with hand-rubbing instructions.²⁸This underscores the need to evaluate new protocols in the routine context.

As previously reported in intensive care unit patients,²⁸the rate of SSIs was higher when nonantiseptic hand wash was not performedprior to use of AAS. Although the number of observations is too low to performany test, it underscores the importance of the optional simple nonantiseptichand wash in the hand-rubbing protocol. However, we cannot exclude that surgicalpersonnel did not perform previous nonantiseptic hand wash before hand-rubbingin the case of an emergency procedure with a higher risk for SSI (confoundingby indication).

We chose each surgical service for initial randomization of the antisepsisprotocol. This allowed us to evaluate the compliance and tolerance of eachprotocol during 1-month periods. In addition, the alternative antiseptic wasremoved from the surgical service at each crossover, as contamination betweenprotocols of a study increases the chances of declaring equivalence in theequivalence trials.²⁹

As reported in previous studies, AAS was, on average, better toleratedthan traditional hand-scrubbings by the surgery team.^9,30,31Less reported are issues regarding compliance of the operating departmentpersonnel to hand antisepsis protocols. For presurgery hand antisepsis, thecritical end point for compliance is not the occurrence of the protocol buthow well and how long it is performed. We observed significantly better compliancewith the duration of hand hygiene in the AAS hand-rubbing group, and thiseffect persisted throughout the 14-month evaluation. One possible explanationis that the necessary duration of hand-rubbing in the AAS-based protocol dependson the amount of AAS applied, whereas the hand-scrubbing protocol can be foreshortenedby drying the hands with absorbent material. Contrary to studies performedin nonsurgical settings,^26,30compliance was also improved by the use of AAS in the surgeon or assistantsubgroup; this subgroup had already been identified³²as complying poorly with hand-hygiene regimens. The fact that the rate ofSSI is equivalent in both groups, despite a better compliance in the hand-rubbinggroup is not surprising given the low SSI occurrence rate.

A previous French study³³ has comparedthe costs of the 2 techniques for hand and forearm antisepsis before scheduledorthopedic surgery. They reported a relative cost of 203 euros per week whenusing povidone iodine or chlorhexidine gluconate and 25 euros per week whenusing AAS (1 euro-US $1.03). Nonetheless, AAS may not be accepted or toleratedby all surgical personnel. Thus, we do not believe that AAS should systematicallyreplace surgical hand antisepsis with traditional hand-scrubbings for economicreasons. The choice of the technique for hand and forearm antisepsis beforesurgery should remain a matter of personal preference among users. In conclusion,given its equivalence to standard hand-scrubbing in preventing SSI, we considerthat preoperative hand-rubbing with AAS preceded by a nonantiseptic hand washis a safe alternative.