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Trial registered on ANZCTR


Registration number
ACTRN12615001045505
Ethics application status
Approved
Date submitted
22/09/2015
Date registered
7/10/2015
Date last updated
2/12/2016
Type of registration
Prospectively registered

Titles & IDs
Public title
Aqueous vs Alcoholic Antisepsis with Chlorhexidine for skin Excisions - The AVALANCHE trial.
Scientific title
Preoperative skin antisepsis with aqueous vs alcoholic chlorhexidine for the prevention of surgical site infection after minor skin excisions in general practice - a randomised controlled trial.
Secondary ID [1] 287478 0
Nil
Universal Trial Number (UTN)
U1111-1167-4953
Trial acronym
AVALANCHE
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Surgical Site Infection 296221 0
Condition category
Condition code
Skin 296494 296494 0 0
Other skin conditions
Infection 296501 296501 0 0
Studies of infection and infectious agents

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Preoperative skin antisepsis with 0.5% chlorhexidine dissolved in 70% alcohol applied to the surgical site immediately prior to minor skin excisions in general practice.

Approximately 30mL of antiseptic solution will be applied over skin surface at the site of the planned excision using a soaked gauze so as to cover an area 1cm greater at all borders than the area of skin exposed by the sterile drape which will be placed over the site of the incision.

Practice nurses at each participating practice are the principal data collectors for this trial, and will also be responsible for assuring that for each excision, the correct surgical protocol is adhered to, and if it is not, that this is documented in the data collection sheets they are responsible for filling out about each patient.
Intervention code [1] 292862 0
Prevention
Comparator / control treatment
Preoperative skin antisepsis with 0.5% chlorhexidine dissolved in water applied to the surgical site immediately prior to minor skin excisions in general practice.

Approximately 30mL of antiseptic solution will be applied over skin surface at the site of the planned excision using a soaked gauze so as to cover an area 1cm greater at all borders than the area of skin exposed by the sterile drape which will be placed over the site of the incision.

Practice nurses at each participating practice are the principal data collectors for this trial, and will also be responsible for assuring that for each excision, the correct surgical protocol is adhered to, and if it is not, that this is documented in the data collection sheets they are responsible for filling out about each patient.
Control group
Active

Outcomes
Primary outcome [1] 296123 0
Surgical site infection (SSI) diagnosed in accordance with a modified version of the CDC definition for surgical site infection:

- Infection occurs within 30 days after the excision
AND
- Infection involves ONLY skin or subcutaneous tissue of the incision
AND at least ONE of the following:
- Purulent drainage with or without laboratory confirmation from the superficial incision
- At least one of the following signs or symptoms: pain or tenderness, localised swelling, redness or heat
- Diagnosis of superficial SSI by the general practitioner or practice nurse

DO NOT INCLUDE AS A SSI: Stitch abscess- minimal inflammation and discharge confined to the points of suture penetration.
Timepoint [1] 296123 0
Within 30 days of the operation:

Patients’ wounds will be assessed for evidence of SSI by doctors or nurses at participating practices when they present for removal of sutures, or at any other time if they present for wound review due to signs and/or symptoms of SSI, or opportunistically if they re-present for any other reason.
Secondary outcome [1] 317555 0
Adverse reaction to the preoperative skin antiseptic agent, manifesting as either of;

1) anaphylaxis
2) skin irritation or contact dermatitis
3) rash
Timepoint [1] 317555 0
Within 30 days of the operation:

Patients will be assessed for evidence of an adverse reaction to the skin preparations by doctors or nurses at participating practices on the day of the procedure and when they present for removal of sutures, or at any other time if they present for wound review due to signs and/or symptoms of an adverse reaction, or opportunistically if they re-present for any other reason.

Eligibility
Key inclusion criteria
All patients over the age of 18 undergoing minor skin procedures at the participating practices during the study period who have capacity to give informed consent and are able to return for removal of sutures.

Patients who are not presenting for:

Excision of sebaceous cyst
Suturing of lacerations
Excisions not requiring sutures, such as shave biopsies
Excisions on body sites where adrenaline is contraindicated
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Allergy to alcohol or chlorhexidine
Evidence of infection at or adjacent to the operative site
Current use of antibiotics
Clinical indication for antibiotic treatment following excision (besides SSI)
Peri-ocular excisions
Patients with a primary language other than English for which certi?ed translation services for that language are not available

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A computer-generated random number table will be used to assign patients to either the alcoholic or aqueous chlorhexidine group.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
Intervention assignment
Other design features
Phase
Type of endpoint(s)
Safety/efficacy
Statistical methods / analysis
SPSS software will be used to analyse the data.

Our sample size calculation has been based upon data from previous trials investigating SSI in the Mackay region. Based upon pooled analyses of these trials, the weighted mean SSI rate following minor skin excisions in general practice in the Mackay region is 9.35%, which we have rounded up to 10% for the purposes of the sample size calculation. As the skin antiseptic preparation in these trials was predominantly aqueous chlorhexidine, this number has been used to represent the baseline SSI rate.

It has been decided through group discussion between GPs in the area in the past that an absolute decrease in SSI rate of 5% would be considered clinically significant; i.e. that if alcoholic chlorhexidine was to reduce SSI rate by 5% with respect to aqueous chlorhexidine, this would be considered clinically significant. Using these numbers, based upon calculations carried out by the statistician for this trial, it has been discovered that to assert that there is a clinically significant difference between the aqueous and alcoholic chlorhexidine preparations used in this trial insofar as their efficacy in reducing SSI with statistical confidence, a power in excess of 80% and a significance level of 0.05, a total of 435 patients would be required in the intervention group and 435 patients in the control group; thus 870 in total.

However, as is standard practice, we will aim to enrol slightly more patents than this to account for drop out. As the drop-out rate in the other aforementioned similar trials investigating SSI in general practice in Mackay has never exceeded 5%, we estimate that an extra 50 patients will be sufficient. Therefore, we will aim to enrol 920 patients for this study.

1. Heal C, Buettner P, Cruickshank R. Does single application of topical chloramphenicol to high risk sutured wounds reduce incidence of wound infection after minor surgery? Prospective randomised placebo controlled double blind trial. BMJ. 2009; Jan 15;338:a2812. doi: 10.1136/bmj.a2812.
2. Heal C, Buttner P, Raasch B et al. Can sutures get wet? Prospective randomised controlled trial of wound management in general practice. BMJ. 2006; 332(7549) 1053-1056.
3. Heal C, Sriharan S, Kimber D et al. Comparing non-sterile to sterile gloves for minor surgery: a prospective randomised controlled non-inferiority trial. Med J Aust. 2015[cited 2015 January 6]; 202(1):27-31.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
QLD

Funding & Sponsors
Funding source category [1] 292056 0
Other Collaborative groups
Name [1] 292056 0
Royal Australian College of General Practitioners
Address [1] 292056 0
100 Wellington Parade, East Melbourne, VIC 3002
Country [1] 292056 0
Australia
Funding source category [2] 292057 0
University
Name [2] 292057 0
James Cook University
Address [2] 292057 0
C/- James Cook University College of Medicine and Dentistry
Mackay Clinical School
Level 1, Building K
Mackay Base Hospital
475 Bridge Rd
Mackay, QLD, 4740
Country [2] 292057 0
Australia
Primary sponsor type
University
Name
James Cook University
Address
C/- James Cook University College of Medicine and Dentistry
Mackay Clinical School
Level 1, Building K
Mackay Base Hospital
475 Bridge Rd
Mackay, QLD, 4740
Country
Australia
Secondary sponsor category [1] 290728 0
Individual
Name [1] 290728 0
Daniel Charles
Address [1] 290728 0
C/- James Cook University College of Medicine and Dentistry
Mackay Clinical School
Level 1, Building K
Mackay Base Hospital
475 Bridge Rd
Mackay, QLD, 4740
Country [1] 290728 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293540 0
James Cook University Human Research Ethics Committee
Ethics committee address [1] 293540 0
Ethics committee country [1] 293540 0
Australia
Date submitted for ethics approval [1] 293540 0
Approval date [1] 293540 0
18/08/2015
Ethics approval number [1] 293540 0

Summary
Brief summary
Preoperative cleansing of the skin with antiseptic preparations at the site of surgical excisions (preoperative skin antisepsis) is common practice before every surgery worldwide, and aims to reduce surgical site infection. However, in most contexts, no definitive scientific consensus exists regarding which preoperative skin antiseptic preparations are most effective. This randomised controlled trial aims to close an existing gap in the evidence base surrounding optimal preoperative skin antisepsis before clean surgery - a practice most general practitioners carry out several times per week when they perform skin excisions. It is currently suspected on the basis of incomplete and methodologically inconsistent evidence that alcoholic antiseptic preparations are likely to be more effective than aqueous preparations for the prevention of surgical site infection (SSI) after clean surgery. This study aims to find definitive proof for this theory by determining whether there is a difference in the incidence of SSI after minor skin excisions in general practice when alcoholic chlorhexidine is used for preoperative skin antisepsis by comparison to when aqueous chlorhexidine is used. It is hypothesised that use of alcoholic chlorhexidine will reduce SSI by comparison to aqueous chlorhexidine.

To implement this study, multiple general practices in the Mackay region which perform large numbers of skin excisions each year will be recruited. Consecutive patients over the age of 18 presenting to participating practices will be asked to participate in the trial and those that agree to partake will be randomised by a computer-generated random number table to receive preoperative skin antisepsis with either 0.5% chlorhexidine dissolved in 70% alcohol or 0.5% chlorhexidine dissolved in water. All other techniques and materials used for both preoperative skin antisepsis and the skin excision itself, as well as all aspects of post-operative care, will be kept constant between the two groups, and will align with a pre-specified surgical and wound protocol. Following their excision, patients will be assessed for the presence or absence of SSI by their treating doctor or nurse when they present for removal of sutures, or at any other time if they re-present due to suspicion of SSI or for any other reason. Rates of SSI will then be recorded, calculated and compared between the two groups using the statistical analysis software SPSS to determine if there is a significant difference in effectiveness between aqueous and alcoholic chlorhexidine.

Hopefully the results of this study will help to provide direction to doctors regularly carrying out clean surgery, who at present have little definitive evidence to guide their choice of preoperative skin antiseptic preparations. Looking further, if a difference is found between aqueous and alcoholic chlorhexidine, we would aim for this research to impact current guidelines on preoperative skin antisepsis and evoke behaviour change from doctors and nurses which leads to a reduction in SSI rates in general practice.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 60366 0
Mr Daniel Charles
Address 60366 0
C/- James Cook University College of Medicine and Dentistry
Mackay Clinical School
Level 1, Building K
Mackay Base Hospital
475 Bridge Rd
Mackay, QLD, 4740
Country 60366 0
Australia
Phone 60366 0
+61447813514
Fax 60366 0
Email 60366 0
daniel.charles@my.jcu.edu.au
Contact person for public queries
Name 60367 0
Mr Daniel Charles
Address 60367 0
C/- James Cook University College of Medicine and Dentistry
Mackay Clinical School
Level 1, Building K
Mackay Base Hospital
475 Bridge Rd
Mackay, QLD, 4740
Country 60367 0
Australia
Phone 60367 0
+61447813514
Fax 60367 0
Email 60367 0
daniel.charles@my.jcu.edu.au
Contact person for scientific queries
Name 60368 0
A/Prof Clare Heal
Address 60368 0
C/- James Cook University College of Medicine and Dentistry
Mackay Clinical School
Level 1, Building K
Mackay Base Hospital
475 Bridge Rd
Mackay, QLD, 4740
Country 60368 0
Australia
Phone 60368 0
+61748857142
Fax 60368 0
Email 60368 0
clare.heal@jcu.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary