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Optimal hand washing technique to minimize bacterial contamination before neuraxial anesthesia: a randomized control trial
Accepted Manuscript Optimal hand washing technique to minimize bacterial contamination for neuraxial anesthesia: a randomized control trial N. Siddiqui, Z. Friedman, A. McGeer, A. Yousefzadeh, J.C. Carvalho, S. Davies PII: DOI: Reference:
S0959-289X(16)30077-2 http://dx.doi.org/10.1016/j.ijoa.2016.09.006 YIJOA 2498
To appear in:
International Journal of Obstetric Anesthesia
Accepted Date:
24 September 2016
Please cite this article as: Siddiqui, N., Friedman, Z., McGeer, A., Yousefzadeh, A., Carvalho, J.C., Davies, S., Optimal hand washing technique to minimize bacterial contamination for neuraxial anesthesia: a randomized control trial, International Journal of Obstetric Anesthesia (2016), doi: http://dx.doi.org/10.1016/j.ijoa.2016.09.006
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
1 IJOA 16-00140 ORIGINAL ARTICLE Optimal hand washing technique to minimize bacterial contamination for neuraxial anesthesia: a randomized control trial N. Siddiqui,a Z. Friedman,a A. McGeer,b A. Yousefzadeh,a J.C. Carvalho,a S. Daviesa a
Department of Anesthesia and Pain Management, Mount Sinai Hospital, University of Toronto,
Toronto, ON, Canada b
Department of Microbiology, Mount Sinai Hospital, University of Toronto, Toronto ON, Canada
Short title: Hand washing techniques
Data for this study were presented at the Canadian Anesthesiologist Society Annual Meeting, 15– 18 June 2012, Quebec City, Quebec, Canada. Correspondence to: Naveed Siddiqui, Department of Anesthesia and Pain Management, Mount Sinai Hospital, University of Toronto, 600 University Avenue, Toronto M5G1X5, ON, Canada. E-mail address: [email protected]
2 ABSTRACT Introduction: Infectious complications related to neuraxial anesthesia may result in adverse outcomes. There are no best practice guidelines regarding hand-sanitizing measures specifically for these procedures. The objective of this study was to compare the growth of microbial organisms on the operator’s forearm between five common techniques of hand washing for labor epidurals. Methods: In this single blind randomized control trial, all anesthesiologists performing labor epidurals in a tertiary care hospital were randomized into five study groups: hand washing with alcohol gel only up to elbows (Group A); hand washing with soap up to elbows, sterile towel to dry, followed by alcohol gel (Group B); hand washing with soap up to elbows, non-sterile towel to dry, followed by alcohol gel (Group C); hand washing with soap up to elbows, non-sterile towel to dry (Group D) or hand washing with soap up to elbows, sterile towel to dry (Group E). The number of colonies for each specimen/rate per 100 specimens on one or both arms per group was measured. Results: The incidence of colonization was 2.5, 23.0, 18.5, 114.5, and 53.0 in Groups A, B, C, D and E, respectively. Compared to Group A, the odds ratio of bacterial growth for Group B was 1.52 (P=0.519), Group C 5.44 (P=0.003), Group D 13.82 (P<0.001), and Group E 8.65 (P<0.001). Conclusion: Alcohol-based antiseptic solutions are superior in terms of reducing the incidence of colonization. The results will enable us to develop guidelines to standardize and improve handsanitizing practices among epidural practitioners.
Keywords: Hand washing; Alcohol gel; Bacterial colonization
Introduction Infection associated with neuraxial anesthesia may result in morbidity and mortality.1 Potential complications vary from superficial skin infection to meningitis, paralysis and death.2,3 The incidence of infectious complications has been reported variably in the literature.1 Although the frequency of disabling injuries is rare, infection is the leading cause of obstetrical neuraxial injury claims in the USA.4 In 2004, the American Society of Regional Anesthesia (ASRA) recognized the paucity of high-quality evidence examining components of the aseptic technique.5
3 Despite the fact that there is a strong association between poor hand hygiene and infectious complications, cross-contamination between health care providers and their patients continues to occur.1 Proper hand washing is a basic component of aseptic technique, and has been shown to decrease both bacterial load on hands and nosocomial infection rate.6 European guidelines require strict asepsis that includes hand washing,7 and the USA Centre for Disease Control and Prevention (CDC) mandates hand washing before donning sterile gloves.8 There is, however, no clear evidence that hand washing reduces epidural catheter-related infection. We recently conducted a study that compared gowning practice for performing epidural analgesia in laboring women. The results showed no significant differences between gowned and un-gowned groups in reducing the rate of epidural catheter tip colonization. Despite both gowned and un-gowned groups using the same technique for antiseptic preparation of the patient’s skin, the incidence of catheter tip colonization with skin flora was relatively high in both groups.9 This may have been a result of poor hand-washing, particularly when gowns were not worn. In our institution, the operator’s forearms are usually exposed during epidural catheter insertion, and may repeatedly cross the sterile area. These results prompted investigation of the best method for hand and arm washing before performing neuraxial anesthesia. Anesthesia trainees learn the manual skills of epidural insertion during their training, but do not learn aseptic procedures.10 This reflects gaps in the teaching curricula, and the importance of standardizing aseptic practices. Currently there are no guidelines outlining optimum hand and arm washing technique for labor epidural analgesia. The standards of aseptic technique vary based on physicians’ previous training and local standards of practice. The term ‘aseptic measures’ is very general and covers many aspects of the technique, but does not detail what constitutes appropriate aseptic technique, such as use of sterile gowns or methods of hand and arm disinfection. At our institution, and likely many others, common clinical practice is hand washing with antimicrobial soap and water, sometimes up to the elbows, but often the hands only. Physicians then dry their hands using clean, non-sterile towels and, just before donning sterile gloves, apply antiseptic alcohol solution to their hands. These practices vary greatly between different physicians within and across institutions.11 There is a need to determine optimal hand and arm washing techniques before performing neuraxial anesthesia.
4 The purpose of this study was to compare the efficacy of five commonly used hand and arm washing techniques by examining their effect on the number of colony forming units (CFU) and the presence of microorganisms in a cultured sample collected from the operator’s forearm.
Methods This study was approved by the Research Ethics board of Mount Sinai Hospital, Toronto, Canada (REB# 09-0075-E). Informed written consent was obtained from all participating patients and physicians. Staff anesthesiologists, anesthesia fellows and residents consented to participate in the study. It was not possible to blind the practitioner to the group allocated for hand sanitization, and only the microbiologist handling the specimen was blinded to group allocation. Epidural insertions were assigned randomly into five different groups via a sealed envelope. Randomization was made using a computer-assisted program, and was based on the five most common methods of hand and arm washing used at this institution. •
Group A: 5 mL aliquots of alcohol gel (Endure 300 Cida-Rinse Gel by Ecolab) applied to hands and forearms up to the elbows; cultures were obtained 60 s after alcohol gel application when hand and arms were air-dried.
•
Group B: antimicrobial soap containing 0.3% Triclosan (Bacti-stat AE Healthcare by Ecolab) for 3 min hand washing up to the elbows, a sterile towel to dry, followed by alcohol gel application; cultures were obtained after the hands and arms were air-dried following alcohol gel application.
•
Group C: antimicrobial soap containing 0.3% Triclosan for 3 min handwashing up to the elbows, a non-sterile towel to dry, followed by alcohol gel application; cultures were obtained after the hands and arms were air-dried following alcohol gel application.
•
Group D: antimicrobial soap containing 0.3% Triclosan for 3 min handwashing up to the elbows and a non-sterile towel to dry, after which cultures were taken.
•
Group E: antimicrobial soap containing 0.3% Triclosan for 3 min handwashing up to the elbows, a sterile towel to dry, after which culture samples were taken. Although an individual practitioner could be assigned randomly into different groups on
different days of study, the sampling was made only once per day per forearm. We also recorded the number of times they had washed their hands before recruitment for the study. Individual physician characteristics including level of training, gender, and arm hair distribution on a 4-point
5 scale, defined as none, mild, moderate and heavy growth were noted. All specimens were obtained using sterile Dacron-tipped swabs (DuPont, Wilmington, DE, USA) pre-moistened in sterile normal saline by a trained research assistant from an area (approximately 5 cm2) on the inside aspect of the middle segment of participant’s forearms. Specimens were coded, placed in thioglycolate broth 1.0 mL (BBL; Becton-Dickinson, Cockeysville, MD, USA) and hand-delivered to the Microbiology Laboratory where cultures were immediately performed. For the purposes of this study we noted any colonization as positive; significant colonization was defined as isolation of more than 10 CFU of any organism.10 The incidence of colonization was defined as the number of colonies for each specimen divided by the rate per 100 specimens.
Statistical analysis Frequencies and percentages were used to describe the occurrence of colonization. To account for the clustered nature of data, unadjusted and adjusted comparisons of colonization across intervention groups were performed using generalized estimating equations analogous to logistic regression with a binomial distribution and logit link and exchangeable correlation matrix (PROC GENMOD, SAS software, version 9.2, SAS Institute, Inc., Cary, NC, USA). All tests were twotailed. A P value of 0.05 or less was considered statistically significant. A total of 1000 specimens were collected in order to detect an absolute reduction in colonization rate from 25% to 5% between any two groups with 90% power using a chi-square test derived from generalized estimating equations. This calculation assumed a design effect of 1.75 due to collecting two specimens per physician, and a type I error of 0.05.
Results A total of 49 epidural practitioners including staff anesthesiologists, anesthesia fellows and residents consented to participate in the study. Five-hundred-and-twenty-two labor epidural insertions were assessed for eligibility and 508 cases were assigned randomly into the five groups. Of these 508 randomized cases, eight did not receive the allocated intervention (Fig. 1). A total of 1000 specimens were collected from 500 epidural insertions (one specimen from each forearm).
6 Practitioner characteristics and the number of times that hand washing was performed before sampling are shown in Table 1. The incidence of colonization was highest in Group D (Table 2), when hand and arm washing was performed using antibacterial soap and water and a non-sterile towel was used to dry the hands (number of colonies per specimen = 114.5). This was followed by Group E in which a sterile towel was used to dry hands without the use of alcohol (n=53.0). The lowest colonization incidence was observed in Group A when alcohol was used as a sole means to cleanse the hands and arms (n=2.5). There was a highly significant difference in colonization rates between groups. When compared to alcohol gel use only, the odds ratio for positive colonization in specimens taken from forearms that were washed with antimicrobial soap and water and dried with a non-sterile towel (Group D) or a sterile towel (Group E) without the use of alcohol were 13.82 and 8.65 respectively (P<0.001) (Table 3). The use of soap followed by non-sterile towel and alcohol gel (Group C) was associated with a 5.44 increased odds ratio of colonization. The only specimens that were not significantly different from the use of alcohol gel alone were those taken from Group B in which the forearms were washed with soap and water, dried with a sterile towel and followed with the application of alcohol (OR: 1.52, 95% CI: 0.43 to 5.37, P=0.52).
Discussion The key finding of the study suggests that alcohol-based hand and arm-washing is better than the other methods tested at reducing the incidence of bacterial colonization. Performing invasive neuraxial procedures requires careful attention to aseptic technique. The term ‘aseptic measures’ is commonly used by the anesthesiologist to document sterile procedures, and may include components such as wearing facemasks, sterile gowns, use of antiseptic solutions, method of hand-washing, and donning sterile gloves. However, the extent to which each component is used varies amongst procedures, institutions and individual practitioners. One survey suggested that the use of all the components is poorly observed and often based on the anesthesiologist’s personal beliefs and region of practice.11 The diversity of practice may be due to the lack of high quality evidence about each facet of aseptic technique, acknowledged in the ASRA recommendations for aseptic technique in regional anesthesia.5 Hand washing is an integral component of infection control and aseptic technique. The commonest source of hospital acquired infection is bacterial transmission from health care
7 workers. Data show that inadequate hand hygiene in health care workers has led to an increase in both adverse events for patients and increased health care costs.12 Invasive procedures performed by anesthesiologists may lead to more deleterious outcomes. We recently studied the effect of gowning on epidural catheter tip colonization.9 Both gowned and un-gowned groups used chlorhexidine and alcohol with appropriate drying time for antiseptic preparation of the patient’s skin; the incidence of catheter tip colonization was relatively high in both groups. A limitation of that study was the practitioner variability in hand and arm washing techniques, which may have been the reason for the high epidural catheter tip colonization rates. The aim of this follow-up study was to determine the best hand and arm washing technic for the performance of major neuraxial anesthesia. The CDC guidelines suggest the best hand hygiene practices for procedures performed in hospital.8 Invasive procedures performed by anesthesiologists, particularly the insertion of central venous cannulae (CVC) and neuraxial anesthesia, carry the potential for severe adverse outcomes. Infection rates for CVC insertion are much higher than for epidural insertion.14 Ample evidence exists for maximum aseptic precautions in central venous cannulation, and includes hand and arm washing up to the elbows, similar to the technique of a full surgical scrub.1 Surgical scrubbing involves a systematic routine with a minimum of 10 min lathering, soaking, and brushing one hand and arm and then the other with a bactericidal agent.15 For labor epidurals anecdotal observations suggest that a full surgical scrub is usually not used, and the optimal method for hands and arm decontamination is not well defined. Performing hand hygiene with basic soap is not truly effective for killing microorganisms.16 The use of alcohol-containing solutions or alcohol alone (e.g., isopropyl alcohol) results in improved disinfection compared to hand washing with plain (i.e. non-alcohol based) antiseptic solutions such as povidone iodine, 4% chlorhexidine, or hexachlorophene.13 When antiseptic solutions are combined with an alcohol compound (e.g., chlorhexidine gluconate in ethyl alcohol), bacterial regrowth may occur at significantly slower rates.13 It is therefore recommended that healthcare providers perform hand hygiene with an alcohol-based antiseptic solution for maximal bactericidal effect.17 The results of the current study show that use of alcohol-based methods is superior to the other techniques studied, and also support use of sterile towels to dry hands after washing with soap. Based on study results our institutional practice was changed: non-sterile towels were replaced with sterile ones to reduce the risk of infective complications.
8 Contrary to our initial assumption, the results show that hand-washing followed by the use of sterile towels and alcohol gel was less effective than the use of alcohol gel alone. We believe that this most likely represents a less strict technique of applying the alcohol gel following hand washing, as opposed to when it was performed as a single technique, and possibly could be a result of moisture left on the skin after washing and before the use of the alcohol gel. A limitation of this study is that although we recorded the number of times each epidural practitioner washed their hands before sampling, this was not standardized. Improved hand washing practices by surgeons, anesthesiologists and other health care providers could result in a reduction of mortality and morbidity.1 The findings of this study confirm the superiority of alcohol-based antiseptic solution in reducing bacterial growth before performing neuraxial anesthesia. This may enable development of evidence-based guidelines to standardize aseptic technique among physicians, aid the design of educational programs and highlight areas for further research.
Disclosure This work was supported by the Department of Anesthesia and Pain Management Mount Sinai Hospital. The authors have no conflicts of interest to declare.
References 1.
Hebl JR, Niesen AD. Infectious complications of regional anesthesia. Curr Opin Anaesthesiol 2011; 24:573-80.
2.
Moen V, Dahlgren N, Irestedt L. Severe neurological complications after central neuraxial blockades in Sweden 1990-1999. Anesthesiology 2004; 101:950-9.
3.
Cook TM, Counsell D, Wildsmith JA. Major complications of central neuraxial block: Report on the Third National Audit Project of the Royal College of Anesthetists. Br J Anaesth 2009; 102:179-90.
4.
Lee LA, Posner KL, Domino KB, Caplan RA, Cheney FW. Injuries associated with regional anesthesia in the 1980s and 1990s. Anesthesiology 2004; 101:143-52.
5.
Hebl JR: The importance and implications of aseptic techniques during regional anesthesia. Reg Anesth Pain Med 2006; 31:311-323.
9 6.
Doebbeling BN, Stanley GL, Sheetz CT, et al. Comparative efficacy of alternative handwashing agents in reducing nosocomial infections in intensive care units. N Engl J Med 1992; 327:88-93.
7.
Royal College of Anesthetists. Good practice in the management of continuous epidural analgesia in the hospital setting. Nov 2010. https://www.rcoa.ac.uk/system/files/FPMEpAnalg2010_1.pdf [accessed April 2015]
8.
Guidelines for Hand Hygiene in Healthcare Settings Published 2002.October 25, 2002 / Vol. 51 / No. RR-16. http://www.cdc.gov/handhygiene/Guidelines.html. [accessed April 2015]
9.
Siddiqui NT, Davies S, McGeer A, Carvalho JC, Friedman Z. The effect of gowning on labor epidural catheter colonization rate: a randomized controlled trial. Reg Anesth Pain Med 2014; 39:520-4.
10. Friedman Z, Siddiqui N, Katznelson R, Devito I, Davies S. Experience is not enough: repeated breaches in epidural anesthesia aseptic technique by novice operators despite improved skill. Anesthesiology 2008; 108:914-20 11. Sellors JE, Cyna AM, Simmons SW: Aseptic precautions for inserting an epidural catheter: a survey of obstetric anesthetists. Anaesthesia 2002; 57:593-6. 12. Maki DG, Weise CE, Sarafin HW. A semi quantitative culture method for identifying intravenous-catheter-related infection. N Engl J Med 1977; 296:1305-9. 13. Larson EL, APIC Guidelines Committee. APIC guideline for handwashing and hand antisepsis in health care settings. Am J Infect Control 1995; 23:251-69. 14. Ramritu P, Halton K, Cook D, Whitby M, Graves N. Catheter-related bloodstream infections in intensive care units: a systematic review with meta-analysis. J Adv Nurs 2008; 62:3-21. 15. Gardner D, Anderson-Man E. “How to Perform A Surgical Hand Scrub”. Infection control Today, Scrub, Gown and Glove Procedures, (Subcourse MD0933 Edition 100) Brookside Press 2008. 16. Kampf G, Kramer A. Epidemiologic background of hand hygiene and evaluation of the most important agents for scrubs and rubs. Clin Microbiol Rev. 2004; 17:863-93. 17. Pittet D, Simon A, Hugonnet S, Pessoa-Silva CL, Sauvan V, Perneger TV. Hand hygiene among physicians: performance, beliefs, and perceptions. Ann Intern Med 2004; 141:1-8.
10
Table 1 Characteristics of epidural practitioners Overall Alcohol Antimicrobial Antimicrobial Antimicrobial Antimicrobial gel only soap dried soap dried soap dried soap dried with with sterile with nonwith nonsterile towel towel sterile towel sterile towel only followed by followed by alcohol gel alcohol gel Designation Fellow 552 112 96 (48.0%) 124 (62.0%) 124 (62.0%) 96 (48.0%) (55.2%) (56.0%) Resident 234 54 50 (25.0%) 40 (20.0%) 40 (20.0%) 50 (25.0%) (23.4%) (27.0%) Staff 214 34 54 (27.0%) 36 (18.0%) 36 (18.0%) 54 (27.0%) (21.4%) (17.0%) Sex Female 324 72 64 (32.0%) 62 (31.0%) 62 (31.0%) 64 (32.0%) (32.4%) (36.0%) Male 676 128 136 (68%) 138 (69.0%) 138 (69.0%) 136 (68%) (67.6%) (64.0%) Arm hair 0 282 62 58 (29.0%) 52 (26.0%) 52 (26.0%) 58 (29.0%) (28.2%) (31.0%) 1 120 32 20 (10.0%) 24 (12.0%) 24 (12.0%) 20 (10.0%) (12.0%) (16.0%) 2 294 50 56 (28.0%) 66 (33.0%) 66 (33.0%) 56 (28.0%) (29.4%) (25.0%) 3 304 56 66 (33.0%) 58 (29.0%) 58 (29.0%) 66 (33.0%) (30.4%) (28.0%) Number of prior hand washing events 0 112 16 28 (14.0%) 20 (10.0%) 20 (10.0%) 28 (14.0%) (11.2%) (8.0%) 1–4 740 148 140 (70.0%) 156 (78.0%) 156 (78.0%) 140 (70.0%) (74.0%) (74.0%) 5–9 108 24 24 (12.0%) 18 (9.0%) 18 (9.0%) 24 (12.0%) (10.8%) (12.0%) ≥10 40 12 8 (4.0%) 6 (3.0%) 6 (3.0%) 8 (4.0%) (4.0%) (6.0%) Data are number (%) Hair 0 = none, 1 = mild growth barely visible, 2= moderate growth easily visible, 3 = heavy growth covers the entire arm.
11 Table 2 Incidence of colonization in each group No Growth
Any growth
Alcohol gel only
196 (98.0%)
4 (2.0%)
Number of colonies per specimen / rate per 100 specimens 2.5
Antimicrobial soap dried with sterile towel followed by alcohol gel Antimicrobial soap dried with nonsterile towel followed by alcohol gel Antimicrobial soap dried with nonsterile towel Antimicrobial soap dried with sterile towel only Data are number (%)
194 (97.0%)
6 (3.0%)
23.0
180 (90.0%)
20 (10.0%)
18.5
156 (78.0%)
44 (22.0%)
114.5
170 (85.0%)
30 (15.0%)
53.0
12 Table 3 Odds ratios Groups
Alcohol gel only Antimicrobial soap dried with sterile towel followed by alcohol gel Antimicrobial soap dried with non-sterile towel followed by alcohol gel Antimicrobial soap dried with non-sterile towel Antimicrobial soap dried with sterile towel only
Positive culture Odds ratio (95% CI) P value 1.00 1.52 (0.43 to 5.37)
0.519
5.44 (1.78 to 16.6)
0.003
13.82 (4.83 to 39.6)
<0.001
8.65 (2.97 to 25.2)
<0.001
IJOA 16-00140 Highlights •
Neuraxial anesthesia requires strict aseptic measures.
•
There is a paucity of best hand washing technique specifically for neuraxial procedures.
•
Simple hand hygiene with basic soap and water is not truly effective.
•
Alcohol based antiseptic solutions are superior in reducing the incidence of colonization.
Figure - 1
CONSORT Flow Diagram Assessed for eligibility (n= 522)
Enrollment
n= epidural practitioners Excluded (n=14) ▪ Not meeting inclusion criteria (n=0) ▪ Declined to participate (n=12) ▪ Other reasons (n= 2)
Randomized (n=508)
Allocation
Allocated to Group A (n= 100) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group B (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group C (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group D (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group E (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
▪ Did not receive allocated intervention (n=0)
▪ Did not receive allocated intervention (n=2)
▪ Did not receive allocated ) intervention (n=2)
▪ Did not receive allocated intervention (n=2)
▪ Did not receive allocated intervention (n=2)
Follow-Up ▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
Analysis Analyzed 200 specimens (n=100)
Analyzed 200 specimens (n=100)
Analyzed 200 Specimens (n=100)
Analyzed 200 Specimens (n=100)
Analyzed 200 Specimens (n=100)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)
S0959-289X(16)30077-2 http://dx.doi.org/10.1016/j.ijoa.2016.09.006 YIJOA 2498
To appear in:
International Journal of Obstetric Anesthesia
Accepted Date:
24 September 2016
Please cite this article as: Siddiqui, N., Friedman, Z., McGeer, A., Yousefzadeh, A., Carvalho, J.C., Davies, S., Optimal hand washing technique to minimize bacterial contamination for neuraxial anesthesia: a randomized control trial, International Journal of Obstetric Anesthesia (2016), doi: http://dx.doi.org/10.1016/j.ijoa.2016.09.006
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
1 IJOA 16-00140 ORIGINAL ARTICLE Optimal hand washing technique to minimize bacterial contamination for neuraxial anesthesia: a randomized control trial N. Siddiqui,a Z. Friedman,a A. McGeer,b A. Yousefzadeh,a J.C. Carvalho,a S. Daviesa a
Department of Anesthesia and Pain Management, Mount Sinai Hospital, University of Toronto,
Toronto, ON, Canada b
Department of Microbiology, Mount Sinai Hospital, University of Toronto, Toronto ON, Canada
Short title: Hand washing techniques
Data for this study were presented at the Canadian Anesthesiologist Society Annual Meeting, 15– 18 June 2012, Quebec City, Quebec, Canada. Correspondence to: Naveed Siddiqui, Department of Anesthesia and Pain Management, Mount Sinai Hospital, University of Toronto, 600 University Avenue, Toronto M5G1X5, ON, Canada. E-mail address: [email protected]
2 ABSTRACT Introduction: Infectious complications related to neuraxial anesthesia may result in adverse outcomes. There are no best practice guidelines regarding hand-sanitizing measures specifically for these procedures. The objective of this study was to compare the growth of microbial organisms on the operator’s forearm between five common techniques of hand washing for labor epidurals. Methods: In this single blind randomized control trial, all anesthesiologists performing labor epidurals in a tertiary care hospital were randomized into five study groups: hand washing with alcohol gel only up to elbows (Group A); hand washing with soap up to elbows, sterile towel to dry, followed by alcohol gel (Group B); hand washing with soap up to elbows, non-sterile towel to dry, followed by alcohol gel (Group C); hand washing with soap up to elbows, non-sterile towel to dry (Group D) or hand washing with soap up to elbows, sterile towel to dry (Group E). The number of colonies for each specimen/rate per 100 specimens on one or both arms per group was measured. Results: The incidence of colonization was 2.5, 23.0, 18.5, 114.5, and 53.0 in Groups A, B, C, D and E, respectively. Compared to Group A, the odds ratio of bacterial growth for Group B was 1.52 (P=0.519), Group C 5.44 (P=0.003), Group D 13.82 (P<0.001), and Group E 8.65 (P<0.001). Conclusion: Alcohol-based antiseptic solutions are superior in terms of reducing the incidence of colonization. The results will enable us to develop guidelines to standardize and improve handsanitizing practices among epidural practitioners.
Keywords: Hand washing; Alcohol gel; Bacterial colonization
Introduction Infection associated with neuraxial anesthesia may result in morbidity and mortality.1 Potential complications vary from superficial skin infection to meningitis, paralysis and death.2,3 The incidence of infectious complications has been reported variably in the literature.1 Although the frequency of disabling injuries is rare, infection is the leading cause of obstetrical neuraxial injury claims in the USA.4 In 2004, the American Society of Regional Anesthesia (ASRA) recognized the paucity of high-quality evidence examining components of the aseptic technique.5
3 Despite the fact that there is a strong association between poor hand hygiene and infectious complications, cross-contamination between health care providers and their patients continues to occur.1 Proper hand washing is a basic component of aseptic technique, and has been shown to decrease both bacterial load on hands and nosocomial infection rate.6 European guidelines require strict asepsis that includes hand washing,7 and the USA Centre for Disease Control and Prevention (CDC) mandates hand washing before donning sterile gloves.8 There is, however, no clear evidence that hand washing reduces epidural catheter-related infection. We recently conducted a study that compared gowning practice for performing epidural analgesia in laboring women. The results showed no significant differences between gowned and un-gowned groups in reducing the rate of epidural catheter tip colonization. Despite both gowned and un-gowned groups using the same technique for antiseptic preparation of the patient’s skin, the incidence of catheter tip colonization with skin flora was relatively high in both groups.9 This may have been a result of poor hand-washing, particularly when gowns were not worn. In our institution, the operator’s forearms are usually exposed during epidural catheter insertion, and may repeatedly cross the sterile area. These results prompted investigation of the best method for hand and arm washing before performing neuraxial anesthesia. Anesthesia trainees learn the manual skills of epidural insertion during their training, but do not learn aseptic procedures.10 This reflects gaps in the teaching curricula, and the importance of standardizing aseptic practices. Currently there are no guidelines outlining optimum hand and arm washing technique for labor epidural analgesia. The standards of aseptic technique vary based on physicians’ previous training and local standards of practice. The term ‘aseptic measures’ is very general and covers many aspects of the technique, but does not detail what constitutes appropriate aseptic technique, such as use of sterile gowns or methods of hand and arm disinfection. At our institution, and likely many others, common clinical practice is hand washing with antimicrobial soap and water, sometimes up to the elbows, but often the hands only. Physicians then dry their hands using clean, non-sterile towels and, just before donning sterile gloves, apply antiseptic alcohol solution to their hands. These practices vary greatly between different physicians within and across institutions.11 There is a need to determine optimal hand and arm washing techniques before performing neuraxial anesthesia.
4 The purpose of this study was to compare the efficacy of five commonly used hand and arm washing techniques by examining their effect on the number of colony forming units (CFU) and the presence of microorganisms in a cultured sample collected from the operator’s forearm.
Methods This study was approved by the Research Ethics board of Mount Sinai Hospital, Toronto, Canada (REB# 09-0075-E). Informed written consent was obtained from all participating patients and physicians. Staff anesthesiologists, anesthesia fellows and residents consented to participate in the study. It was not possible to blind the practitioner to the group allocated for hand sanitization, and only the microbiologist handling the specimen was blinded to group allocation. Epidural insertions were assigned randomly into five different groups via a sealed envelope. Randomization was made using a computer-assisted program, and was based on the five most common methods of hand and arm washing used at this institution. •
Group A: 5 mL aliquots of alcohol gel (Endure 300 Cida-Rinse Gel by Ecolab) applied to hands and forearms up to the elbows; cultures were obtained 60 s after alcohol gel application when hand and arms were air-dried.
•
Group B: antimicrobial soap containing 0.3% Triclosan (Bacti-stat AE Healthcare by Ecolab) for 3 min hand washing up to the elbows, a sterile towel to dry, followed by alcohol gel application; cultures were obtained after the hands and arms were air-dried following alcohol gel application.
•
Group C: antimicrobial soap containing 0.3% Triclosan for 3 min handwashing up to the elbows, a non-sterile towel to dry, followed by alcohol gel application; cultures were obtained after the hands and arms were air-dried following alcohol gel application.
•
Group D: antimicrobial soap containing 0.3% Triclosan for 3 min handwashing up to the elbows and a non-sterile towel to dry, after which cultures were taken.
•
Group E: antimicrobial soap containing 0.3% Triclosan for 3 min handwashing up to the elbows, a sterile towel to dry, after which culture samples were taken. Although an individual practitioner could be assigned randomly into different groups on
different days of study, the sampling was made only once per day per forearm. We also recorded the number of times they had washed their hands before recruitment for the study. Individual physician characteristics including level of training, gender, and arm hair distribution on a 4-point
5 scale, defined as none, mild, moderate and heavy growth were noted. All specimens were obtained using sterile Dacron-tipped swabs (DuPont, Wilmington, DE, USA) pre-moistened in sterile normal saline by a trained research assistant from an area (approximately 5 cm2) on the inside aspect of the middle segment of participant’s forearms. Specimens were coded, placed in thioglycolate broth 1.0 mL (BBL; Becton-Dickinson, Cockeysville, MD, USA) and hand-delivered to the Microbiology Laboratory where cultures were immediately performed. For the purposes of this study we noted any colonization as positive; significant colonization was defined as isolation of more than 10 CFU of any organism.10 The incidence of colonization was defined as the number of colonies for each specimen divided by the rate per 100 specimens.
Statistical analysis Frequencies and percentages were used to describe the occurrence of colonization. To account for the clustered nature of data, unadjusted and adjusted comparisons of colonization across intervention groups were performed using generalized estimating equations analogous to logistic regression with a binomial distribution and logit link and exchangeable correlation matrix (PROC GENMOD, SAS software, version 9.2, SAS Institute, Inc., Cary, NC, USA). All tests were twotailed. A P value of 0.05 or less was considered statistically significant. A total of 1000 specimens were collected in order to detect an absolute reduction in colonization rate from 25% to 5% between any two groups with 90% power using a chi-square test derived from generalized estimating equations. This calculation assumed a design effect of 1.75 due to collecting two specimens per physician, and a type I error of 0.05.
Results A total of 49 epidural practitioners including staff anesthesiologists, anesthesia fellows and residents consented to participate in the study. Five-hundred-and-twenty-two labor epidural insertions were assessed for eligibility and 508 cases were assigned randomly into the five groups. Of these 508 randomized cases, eight did not receive the allocated intervention (Fig. 1). A total of 1000 specimens were collected from 500 epidural insertions (one specimen from each forearm).
6 Practitioner characteristics and the number of times that hand washing was performed before sampling are shown in Table 1. The incidence of colonization was highest in Group D (Table 2), when hand and arm washing was performed using antibacterial soap and water and a non-sterile towel was used to dry the hands (number of colonies per specimen = 114.5). This was followed by Group E in which a sterile towel was used to dry hands without the use of alcohol (n=53.0). The lowest colonization incidence was observed in Group A when alcohol was used as a sole means to cleanse the hands and arms (n=2.5). There was a highly significant difference in colonization rates between groups. When compared to alcohol gel use only, the odds ratio for positive colonization in specimens taken from forearms that were washed with antimicrobial soap and water and dried with a non-sterile towel (Group D) or a sterile towel (Group E) without the use of alcohol were 13.82 and 8.65 respectively (P<0.001) (Table 3). The use of soap followed by non-sterile towel and alcohol gel (Group C) was associated with a 5.44 increased odds ratio of colonization. The only specimens that were not significantly different from the use of alcohol gel alone were those taken from Group B in which the forearms were washed with soap and water, dried with a sterile towel and followed with the application of alcohol (OR: 1.52, 95% CI: 0.43 to 5.37, P=0.52).
Discussion The key finding of the study suggests that alcohol-based hand and arm-washing is better than the other methods tested at reducing the incidence of bacterial colonization. Performing invasive neuraxial procedures requires careful attention to aseptic technique. The term ‘aseptic measures’ is commonly used by the anesthesiologist to document sterile procedures, and may include components such as wearing facemasks, sterile gowns, use of antiseptic solutions, method of hand-washing, and donning sterile gloves. However, the extent to which each component is used varies amongst procedures, institutions and individual practitioners. One survey suggested that the use of all the components is poorly observed and often based on the anesthesiologist’s personal beliefs and region of practice.11 The diversity of practice may be due to the lack of high quality evidence about each facet of aseptic technique, acknowledged in the ASRA recommendations for aseptic technique in regional anesthesia.5 Hand washing is an integral component of infection control and aseptic technique. The commonest source of hospital acquired infection is bacterial transmission from health care
7 workers. Data show that inadequate hand hygiene in health care workers has led to an increase in both adverse events for patients and increased health care costs.12 Invasive procedures performed by anesthesiologists may lead to more deleterious outcomes. We recently studied the effect of gowning on epidural catheter tip colonization.9 Both gowned and un-gowned groups used chlorhexidine and alcohol with appropriate drying time for antiseptic preparation of the patient’s skin; the incidence of catheter tip colonization was relatively high in both groups. A limitation of that study was the practitioner variability in hand and arm washing techniques, which may have been the reason for the high epidural catheter tip colonization rates. The aim of this follow-up study was to determine the best hand and arm washing technic for the performance of major neuraxial anesthesia. The CDC guidelines suggest the best hand hygiene practices for procedures performed in hospital.8 Invasive procedures performed by anesthesiologists, particularly the insertion of central venous cannulae (CVC) and neuraxial anesthesia, carry the potential for severe adverse outcomes. Infection rates for CVC insertion are much higher than for epidural insertion.14 Ample evidence exists for maximum aseptic precautions in central venous cannulation, and includes hand and arm washing up to the elbows, similar to the technique of a full surgical scrub.1 Surgical scrubbing involves a systematic routine with a minimum of 10 min lathering, soaking, and brushing one hand and arm and then the other with a bactericidal agent.15 For labor epidurals anecdotal observations suggest that a full surgical scrub is usually not used, and the optimal method for hands and arm decontamination is not well defined. Performing hand hygiene with basic soap is not truly effective for killing microorganisms.16 The use of alcohol-containing solutions or alcohol alone (e.g., isopropyl alcohol) results in improved disinfection compared to hand washing with plain (i.e. non-alcohol based) antiseptic solutions such as povidone iodine, 4% chlorhexidine, or hexachlorophene.13 When antiseptic solutions are combined with an alcohol compound (e.g., chlorhexidine gluconate in ethyl alcohol), bacterial regrowth may occur at significantly slower rates.13 It is therefore recommended that healthcare providers perform hand hygiene with an alcohol-based antiseptic solution for maximal bactericidal effect.17 The results of the current study show that use of alcohol-based methods is superior to the other techniques studied, and also support use of sterile towels to dry hands after washing with soap. Based on study results our institutional practice was changed: non-sterile towels were replaced with sterile ones to reduce the risk of infective complications.
8 Contrary to our initial assumption, the results show that hand-washing followed by the use of sterile towels and alcohol gel was less effective than the use of alcohol gel alone. We believe that this most likely represents a less strict technique of applying the alcohol gel following hand washing, as opposed to when it was performed as a single technique, and possibly could be a result of moisture left on the skin after washing and before the use of the alcohol gel. A limitation of this study is that although we recorded the number of times each epidural practitioner washed their hands before sampling, this was not standardized. Improved hand washing practices by surgeons, anesthesiologists and other health care providers could result in a reduction of mortality and morbidity.1 The findings of this study confirm the superiority of alcohol-based antiseptic solution in reducing bacterial growth before performing neuraxial anesthesia. This may enable development of evidence-based guidelines to standardize aseptic technique among physicians, aid the design of educational programs and highlight areas for further research.
Disclosure This work was supported by the Department of Anesthesia and Pain Management Mount Sinai Hospital. The authors have no conflicts of interest to declare.
References 1.
Hebl JR, Niesen AD. Infectious complications of regional anesthesia. Curr Opin Anaesthesiol 2011; 24:573-80.
2.
Moen V, Dahlgren N, Irestedt L. Severe neurological complications after central neuraxial blockades in Sweden 1990-1999. Anesthesiology 2004; 101:950-9.
3.
Cook TM, Counsell D, Wildsmith JA. Major complications of central neuraxial block: Report on the Third National Audit Project of the Royal College of Anesthetists. Br J Anaesth 2009; 102:179-90.
4.
Lee LA, Posner KL, Domino KB, Caplan RA, Cheney FW. Injuries associated with regional anesthesia in the 1980s and 1990s. Anesthesiology 2004; 101:143-52.
5.
Hebl JR: The importance and implications of aseptic techniques during regional anesthesia. Reg Anesth Pain Med 2006; 31:311-323.
9 6.
Doebbeling BN, Stanley GL, Sheetz CT, et al. Comparative efficacy of alternative handwashing agents in reducing nosocomial infections in intensive care units. N Engl J Med 1992; 327:88-93.
7.
Royal College of Anesthetists. Good practice in the management of continuous epidural analgesia in the hospital setting. Nov 2010. https://www.rcoa.ac.uk/system/files/FPMEpAnalg2010_1.pdf [accessed April 2015]
8.
Guidelines for Hand Hygiene in Healthcare Settings Published 2002.October 25, 2002 / Vol. 51 / No. RR-16. http://www.cdc.gov/handhygiene/Guidelines.html. [accessed April 2015]
9.
Siddiqui NT, Davies S, McGeer A, Carvalho JC, Friedman Z. The effect of gowning on labor epidural catheter colonization rate: a randomized controlled trial. Reg Anesth Pain Med 2014; 39:520-4.
10. Friedman Z, Siddiqui N, Katznelson R, Devito I, Davies S. Experience is not enough: repeated breaches in epidural anesthesia aseptic technique by novice operators despite improved skill. Anesthesiology 2008; 108:914-20 11. Sellors JE, Cyna AM, Simmons SW: Aseptic precautions for inserting an epidural catheter: a survey of obstetric anesthetists. Anaesthesia 2002; 57:593-6. 12. Maki DG, Weise CE, Sarafin HW. A semi quantitative culture method for identifying intravenous-catheter-related infection. N Engl J Med 1977; 296:1305-9. 13. Larson EL, APIC Guidelines Committee. APIC guideline for handwashing and hand antisepsis in health care settings. Am J Infect Control 1995; 23:251-69. 14. Ramritu P, Halton K, Cook D, Whitby M, Graves N. Catheter-related bloodstream infections in intensive care units: a systematic review with meta-analysis. J Adv Nurs 2008; 62:3-21. 15. Gardner D, Anderson-Man E. “How to Perform A Surgical Hand Scrub”. Infection control Today, Scrub, Gown and Glove Procedures, (Subcourse MD0933 Edition 100) Brookside Press 2008. 16. Kampf G, Kramer A. Epidemiologic background of hand hygiene and evaluation of the most important agents for scrubs and rubs. Clin Microbiol Rev. 2004; 17:863-93. 17. Pittet D, Simon A, Hugonnet S, Pessoa-Silva CL, Sauvan V, Perneger TV. Hand hygiene among physicians: performance, beliefs, and perceptions. Ann Intern Med 2004; 141:1-8.
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Table 1 Characteristics of epidural practitioners Overall Alcohol Antimicrobial Antimicrobial Antimicrobial Antimicrobial gel only soap dried soap dried soap dried soap dried with with sterile with nonwith nonsterile towel towel sterile towel sterile towel only followed by followed by alcohol gel alcohol gel Designation Fellow 552 112 96 (48.0%) 124 (62.0%) 124 (62.0%) 96 (48.0%) (55.2%) (56.0%) Resident 234 54 50 (25.0%) 40 (20.0%) 40 (20.0%) 50 (25.0%) (23.4%) (27.0%) Staff 214 34 54 (27.0%) 36 (18.0%) 36 (18.0%) 54 (27.0%) (21.4%) (17.0%) Sex Female 324 72 64 (32.0%) 62 (31.0%) 62 (31.0%) 64 (32.0%) (32.4%) (36.0%) Male 676 128 136 (68%) 138 (69.0%) 138 (69.0%) 136 (68%) (67.6%) (64.0%) Arm hair 0 282 62 58 (29.0%) 52 (26.0%) 52 (26.0%) 58 (29.0%) (28.2%) (31.0%) 1 120 32 20 (10.0%) 24 (12.0%) 24 (12.0%) 20 (10.0%) (12.0%) (16.0%) 2 294 50 56 (28.0%) 66 (33.0%) 66 (33.0%) 56 (28.0%) (29.4%) (25.0%) 3 304 56 66 (33.0%) 58 (29.0%) 58 (29.0%) 66 (33.0%) (30.4%) (28.0%) Number of prior hand washing events 0 112 16 28 (14.0%) 20 (10.0%) 20 (10.0%) 28 (14.0%) (11.2%) (8.0%) 1–4 740 148 140 (70.0%) 156 (78.0%) 156 (78.0%) 140 (70.0%) (74.0%) (74.0%) 5–9 108 24 24 (12.0%) 18 (9.0%) 18 (9.0%) 24 (12.0%) (10.8%) (12.0%) ≥10 40 12 8 (4.0%) 6 (3.0%) 6 (3.0%) 8 (4.0%) (4.0%) (6.0%) Data are number (%) Hair 0 = none, 1 = mild growth barely visible, 2= moderate growth easily visible, 3 = heavy growth covers the entire arm.
11 Table 2 Incidence of colonization in each group No Growth
Any growth
Alcohol gel only
196 (98.0%)
4 (2.0%)
Number of colonies per specimen / rate per 100 specimens 2.5
Antimicrobial soap dried with sterile towel followed by alcohol gel Antimicrobial soap dried with nonsterile towel followed by alcohol gel Antimicrobial soap dried with nonsterile towel Antimicrobial soap dried with sterile towel only Data are number (%)
194 (97.0%)
6 (3.0%)
23.0
180 (90.0%)
20 (10.0%)
18.5
156 (78.0%)
44 (22.0%)
114.5
170 (85.0%)
30 (15.0%)
53.0
12 Table 3 Odds ratios Groups
Alcohol gel only Antimicrobial soap dried with sterile towel followed by alcohol gel Antimicrobial soap dried with non-sterile towel followed by alcohol gel Antimicrobial soap dried with non-sterile towel Antimicrobial soap dried with sterile towel only
Positive culture Odds ratio (95% CI) P value 1.00 1.52 (0.43 to 5.37)
0.519
5.44 (1.78 to 16.6)
0.003
13.82 (4.83 to 39.6)
<0.001
8.65 (2.97 to 25.2)
<0.001
IJOA 16-00140 Highlights •
Neuraxial anesthesia requires strict aseptic measures.
•
There is a paucity of best hand washing technique specifically for neuraxial procedures.
•
Simple hand hygiene with basic soap and water is not truly effective.
•
Alcohol based antiseptic solutions are superior in reducing the incidence of colonization.
Figure - 1
CONSORT Flow Diagram Assessed for eligibility (n= 522)
Enrollment
n= epidural practitioners Excluded (n=14) ▪ Not meeting inclusion criteria (n=0) ▪ Declined to participate (n=12) ▪ Other reasons (n= 2)
Randomized (n=508)
Allocation
Allocated to Group A (n= 100) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group B (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group C (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group D (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
Allocated to Group E (n=102) 200 specimens ▪ Received allocated Intervention (n=100)
▪ Did not receive allocated intervention (n=0)
▪ Did not receive allocated intervention (n=2)
▪ Did not receive allocated ) intervention (n=2)
▪ Did not receive allocated intervention (n=2)
▪ Did not receive allocated intervention (n=2)
Follow-Up ▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪ Lost to follow up (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
▪Discontinued Regimen (n=0)
Analysis Analyzed 200 specimens (n=100)
Analyzed 200 specimens (n=100)
Analyzed 200 Specimens (n=100)
Analyzed 200 Specimens (n=100)
Analyzed 200 Specimens (n=100)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)
▪ Excluded from analysis (n=0)