Surgical Hand Antisepsis, A Pilot Study comparing Povidone Iodine Hand Scrub and Alcohol-based Chlorhexidine Gluconate Hand Rub

2012-02-14 | Admin MKKI

Original Article

Surgical Hand Antisepsis–A Pilot Study comparing Povidone Iodine Hand Scrub and Alcohol-based Chlorhexidine Gluconate Hand Rub
Kah Weng Lai,Dip AvMed, MRCSEd, MMed (Ortho), Tun Lin Foo,MBBS, Wilson Low, BSc, MSc (Epidemiology), Ganesan Naidu,MRCSEd, MMed (Surg), FRCS (Ortho & Trauma)

Introduction: The surgeon uses different methods of surgical hand antisepsis with the aim of reducing surgical site infections. To date, there are no local studies comparing the efficacy of iodine hand scrub against newer alcohol-based hand rubs with active ingredients. Our pilot study compares a traditional aqueous hand scrub using 7.5% Povidone iodine (PVP-I) against a hand rub using Avagard: 61% ethyl alcohol, 1% chlorhexidine gluconate. The outcome measure is the number of Colony Forming Units (CFU) cultured from 10-digit fingertip imprints on agar plates. Materials and Methods: Ten volunteers underwent 2 hand preparation protocols, with a 30-minute interval in between–Protocol A (3-minute of aqueous scrub using PVP-I) and Protocol B (3-minute of hand rub, until dry, using Avagard). In each protocol, fingertip imprints were obtained immediately after hand preparation (t0). The volunteers proceeded to don sterile gloves and performed specific tasks (suturing). At one hour, the gloves were removed and a second set of imprints was obtained (t1). Results: Four sets of fingertip imprints were obtained. All 10 participants complied with the supervised hand preparation procedures for each protocol. CFUs of initial fingertip imprints (t0): The median CFU counts for initial imprint was significantly higher in the PVP-I treatment (median = 6, Inter Quartile Range (IQR) = 33) compared to the Avagard treatment (median = 0, IQR = 0, P <0.001). CFUs of fingertip imprint at 1 hour (t1): The median CFU counts for second imprint (t1) was significantly higher in the PVP-I treatment (median = 0.5, IQR = 11) compared to the Avagard treatment (median = 0, IQR = 0, P = 0.009). Our results suggest that the Avagard was more efficacious than aqueous PVP-I scrub at reducing baseline colony counts and sustaining this antisepsis effect. Conclusion: Alcohol hand rub with an active compound, demonstrated superior efficacy in CFU reduction. Based on our results, and those pooled from other authors, we suggest that alcohol-based hand rubs could be included in the operating theatre as an alternative to traditional surgical scrub for surgical hand antisepsis.

Ann Acad Med Singapore 2012;41:12-16
Key words: Alcohol-based, Hand rub, Hand scrub, Surgical hand antisepsis, Surgical site infection

Surgical site infection (SSI) is a globally recognised problem that results in significant morbidity (delayed healing, wound breakdown, sepsis) and negative economic impact (prolonged hospital stays, revision surgery). Hand antisepsis remains a cornerstone of the overall aseptic technique in surgery, to eliminate transient micro-organisms and reduce resident skin flora. Despite significant advances in glove manufacturing techniques and development in surgical instruments design, glove perforation rates have been reported to be as high as 17%, reiterating the importance of good hand antisepsis.

Traditional surgical hand antisepsis consists of an aqueous scrub with or without brush, using povidone iodine (PVP-I) or chlorhexidine-based detergents. Some institutions in Singapore have recently started using alcohol-based hand rub as an alternative to the traditional aqueous scrub, whilst continental Europe has used such alcohol-based hand rubs for more than 30 years.

The increasing use of alcohol-based hand rubs have led to trials studying its efficacy as an alternative to traditional hand scrubbing for hand antisepsis in surgery. The current evidence for surgical hand antisepsis suggests that alcohol-based hand rubs performed better than aqueous hand scrubs (including PVP-I) at reducing colony forming units (CFU), which serves as a surrogate predictor of SSIs. However, this did not necessarily translate into significant reduction of surgical morbidity.

Previous studies compared alcohol rubs with other active compounds (chlorhexidine gluconate, mecetronium, zinc) against each other and against aqueous scrubs (chlorhexidine, PVP-I). These found that alcohol hand rubs with additional active compounds were as-or-more effective than aqueous scrubs at reducing CFUs, cost 67% less, and have a sustained bactericidal activity. Chlorhexidine’s property of adhering to the stratum corneum of the skin allows it to exert a residual antimicrobial effect of up to 6 hours. Nonetheless, between the additive active compounds within the alcohol rubs, none were noted to be significantly better.

Currently in Singapore’s restructured hospitals, alcohol-based hand rubs are not routinely used for surgical hand antisepsis. As there have been no local studies comparing aqueous hand scrubs against alcohol hand rubs with other active ingredients, the aim of this pilot study compares the standard 7.5% Povidone iodine aqueous hand scrub against the alcohol-based hand rub Avagard [1% chlorhexidine gluconate, 61% ethyl alcohol (3M, MN, USA)] to determine the feasibility of using alcohol-based hand rubs as a viable alternative for surgical hand antisepsis in local operating theatres. CFU is used as the outcome measure to enable quantitative analysis of the results.

Materials and Methods
Study Design
Ten volunteers were recruited in this non-randomised within-subject cohort study conducted during a suture practice workshop held at a clean experimental surgical laboratory equipped with standard operating facilities and hand scrub stations. The workshop consisted of 2 distinct suture practice sessions (lasting an hour each), where the subjects underwent a supervised hand preparation protocol prior to commencement of each suture practice. The subjects’ fingertip imprints were sampled for CFU counts before and after each practice session.

Inclusion criteria for the subjects were practising doctors who had prior experience of surgical hand scrub in an operating theatre environment. The subjects had no known history of upper limb infections or recent trauma to the fingers and hands. All subjects were informed of the risks and benefits involved in this study and informed consent to participate in this study was obtained.

Participants were briefed and underwent rehearsal of the study procedures on the same day of the workshop. A familiarisation hand scrub/rub was demonstrated to the subjects, and they performed a ‘dry’ scrub/rub, i.e. no solutions were used. Prior to each hand preparation protocol, all participants underwent 1 minute of hand washing with a neutral soap and a sponge-bristle brush to remove gross contaminants.

Detailed Hand Preparation Protocol
The study participants underwent 2 sequential hand preparation protocols:
Protocol A: Three minutes of traditional scrub (PVP-I) followed by 1 hour of basic suture practice.
Protocol B: Three minutes of hand rubbing, until dry (Avagard) followed by 1 hour of suture practice.

After general cleansing with neutral soap, participants commenced Protocol A with a timed 3-minute hand scrubbing with 15 ml (3 full squirts) of PVP-I. Hands were dried with sterile towels and the initial sets of 2 x 5-digit fingertip imprint were obtained, applying gentle pressure of finger pulps onto 2 blood agar plates (1 plate for each hand) for 5 seconds. Thereafter, gloves were donned using a no-touch technique and participants proceeded to perform specific tasks (suturing, knot-tying) as part of a suturing workshop. After one hour, the gloves were removed, also via a no-touch technique. The subsequent sets of 2 x 5-digit imprints were then obtained.

A 30-minute interval was mandated, where participants were allowed to use their hands normally with no restriction.

After the break, a similar sequence for Protocol B was repeated. Cleansing began with neutral hand wash. Thereafter, 15ml (3 full squirts) of Avagard was dispensed onto each participant’s hands, and covered completely before rubbing commenced. Sterile towels were not required as rubbing continued until solution evaporated and hands were dry. 2 x 5-fingertip imprints were obtained before and after donning and doffing gloves respectively for the second suture practice session.

Compliance officers (operating theatre scrub nurses, authors – KWL, TLF) were present at every station (neutral hand wash, surgical hand preparation, hand drying, gloving, suture practice and removal of gloves) to ensure proper technique and adherence to sterile procedures.

The agar plates were delivered to the hospital’s Microbiology Department for incubation upon collection. After 48 hours of incubation, colony counts were obtained. Species identification was not performed because the primary focus is to obtain a quantitative rather than a qualitative analysis.

Statistical Analysis
The distribution of the CFU counts was expressed as median and interquartile range (IQR). Comparison of median for paired data was performed using Wilcoxon signed-rank test. All statistical analysis was conducted using STATA (version 10; Stata, College Station, TX), Statistical significance was assumed as P <0.05.

Four sets (PVP-I: t0, t1; Avagard: t0, t1) of fingertip imprints (20 hands in each set) were obtained (Table 1). All 10 participants complied with the standard operating procedure for each station and protocol. One participant (Subject 8) had to repeat the steps for Protocol A due to a breach in sterility 10 minutes into the suture practice.

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