Surgical gowns as a safety barrier under non-standard environmental conditions

In this prospective study, we aimed to investigate whether surgical gowns become contaminated during surgery. Samples from the gowns of five surgeons during 19 surgeries were collected using sterile swabs in circular standard delimited areas on both wrists and the mid-chest at three time-points: immediately before surgical incision (t=0), 30 min (t=30), and 60 min (t=60) later. Additionally, at t=0 and t=60, three settle plates of plate count agar were positioned at 1.5 m from the ground and remained open for 20 min. The operating room temperature and relative humidity were monitored. The swabs were cultivated and incubated, and colony-forming units per gram (CFU/g) counts were measured. The CFU/g counts for bacteria or fungi did not differ among the three sampling sites. The surgeons' lateral dominance in manual dexterity did not influence the gowns' contamination. There were significant variations in the temperature and relative humidity over time, but not in the CFU/g counts. In conclusion, during the first hour of surgery, surgical gowns did not become a source of contamination and are an effective barrier against bacterial and fungal contamination even under non-standard surgical environmental conditions.

An Antimicrobial Fabric Using Nano-Herbal Encapsulation of Essential Oils

Lab coats are widely used in biohazard laboratories and healthcare facilities as protective garments to prevent direct exposure to pathogens, spills, and burns. These cotton-based protective coats provide ideal conditions for microbial growth and attachment sites due to their porous nature, moisture-holding capacity, and retention of warmth from the user's body. Several studies have demonstrated the survival of pathogenic bacteria on hospital garments and lab coats, acting as vectors of microbial transmission. A common approach to fix these problems is the application of antimicrobial agents in textile finishing, but concerns have been raised due to the toxicity and environmental effects of many synthetic chemicals. The ongoing pandemic has also opened a window for the investigation of effective antimicrobials and eco-friendly and toxic-free formulations. This study uses two natural bioactive compounds, carvacrol and thymol, encapsulated in chitosan nanoparticles, which guarantee effective protection against four human pathogens with up to a 4-log reduction (99.99%). These pathogens are frequently detected in lab coats used in biohazard laboratories. The treated fabrics also resisted up to 10 wash cycles with 90% microbial reduction, which is sufficient for the intended use. We made modifications to the existing standard fabric tests to better represent the typical scenarios of lab coat usage. These refinements allow for a more accurate evaluation of the effectiveness of antimicrobial lab coats and for the simulation of the fate of any accidental microbial spills that must be neutralized within a short time. Further studies are recommended to investigate the accumulation of pathogens over time on antimicrobial lab coats compared to regular protective coats.

Operating Room and Hospital Air Environment

One method of preventing surgical-site infection is lowering intraoperative environmental contamination. The authors sought to evaluate their hospital's operating room (OR) contamination rate and compare it with the remainder of the hospital. They tested environmental contamination in preoperative, intraoperative, and postoperative settings for a total joint arthroplasty patient. A total of 190 air settle plates composed of trypsin soy agar were placed in 19 settings within the hospital. Locations included the OR with light and heavy traffic, with and without masks, jackets, and shoe covers; the substerile room; OR hallways; the sterile equipment processing center; preoperative areas; post-anesthesia care units; orthopedic floors; the emergency department; OR locker rooms and restrooms; a resident's home; and controls. The trypsin soy agar plates were incubated at 36 °C for 48 hours. Colony counts were performed for each plate. Average colony-forming units (CFUs) were calculated in each setting. The highest CFUs were in the OR locker room, at 28 CFUs per plate per hour. Preoperative and post-anesthesia care unit holding areas were 7.4 CFUs and 9.6 CFUs, respectively. The main orthopedic surgical ward had 10.0 CFUs per plate per hour, whereas the VIP hospital ward had 17.0 CFUs per plate per hour. All OR environments had low CFUs. A live OR had slightly higher CFUs than settings without OR personnel. In comparison with the local community household, the OR locker room, restrooms, hospital orthopedic wards, emergency department, preoperative holding, post-anesthesia care unit, and OR hallway all had higher airborne contamination. On the basis of these results, the authors recommend environmental sampling as a simple, fast, inexpensive tool for monitoring airborne contamination. [Orthopedics. 2021;44(3):e414-e416.].

Microbial Contamination Risk and Disinfection of Radiation Protective Garments

ABSTRACT

Healthcare-associated infections are a major public health concern for both patients and medical personnel. This has taken on greater urgency during the current COVID-19 pandemic. Radiation Personal Protective Equipment (RPPE) may contribute to risks of microbial contamination. This possibility was tested in 61 personal or shared-use lead aprons and thyroid collars at Columbia Presbyterian Irving Medical Center. Fifty percent tested positive for either bacterial or fungal contamination, mostly around the neckline of lead vests and thyroid collars. Repeated testing of garments some weeks to months later confirmed continued presence of microbial contamination. The possibility that hospital-approved disinfection agents could degrade the radio-protective features of these garments was also examined. Samples of identical construction to garments in regular use were subjected to either daily or weekly wipes with hypochlorite or alcohol-based hospital-approved cleaning agents for 6 mo. A third group of samples was maintained in contact with the cleaning agents for 6 mo. All samples were fluoroscoped four times during the study. None demonstrated any degradation in radioprotection. All samples were photographed monthly. Physical degradation of the outer plastic covering by concentrated hypochlorite and limited mechanical damage around stitched seams of the samples cleaned daily with alcohol was noted. Based on the high prevalence of microbial contamination, regular cleaning and disinfection protocols should be implemented. Regular cleaning with medical-facility-approved cleaning and disinfecting agents is likely to be effective at reducing the microbial load and unlikely to result in significant reduction in radioprotective properties of these garments.

Bacterial contamination of medical providers' white coats and surgical scrubs: A systematic review

BACKGROUND

Horizontal transmission of bacteria, especially multidrug-resistant organisms (MDROs), remains an important concern in hospitals worldwide. Some studies have implicated provider attire in the transmission of organisms within hospitals, whereas others have suggested that evidence supporting this notion is limited.

METHODS

PubMed was searched for publications between 1990 and 2018 to identify studies of bacterial contamination of, or dissemination of, bacteria from physician, nursing, or trainee attire, with a specific focus on white coats and surgical scrubs. A total of 214 articles were identified. Of these, 169 were excluded after abstract review and 33 were excluded after in-depth full manuscript review.

RESULTS

Twenty-two articles were included: 16 (73%) cross-sectional studies, 4 (18%) randomized controlled trials, and 2 (9%) cohort studies. Results are organized by microbial contaminants, antibiotic resistance, types of providers, fabric type, antimicrobial coating, and laundering practices. Provider attire was commonly colonized by MDROs, with white coats laundered less frequently than scrubs. Studies revealed considerable differences among fabrics used and laundering practices.

CONCLUSIONS

Findings suggest that provider attire is a potential source of pathogenic bacterial transmission in health care settings. However, data confirming a direct link between provider attire and health care-associated infections remain limited. Suggestions outlined in this article may serve as a guideline to reduce the spread of bacterial pathogens, including MDROs, that have the potential to precipitate hospital-acquired infections.

Bacterial Contamination of Lead Aprons in a High-Volume Cardiac Catheterization Laboratory and Disinfection Using an Automated Ultraviolet-C Radiation System

OBJECTIVES

Quantify and characterize bacterial contamination of lead aprons in a high-volume catheterization laboratory and evaluate the efficacy of decontamination using an ultraviolet-C (UV-C) radiation system.

BACKGROUND

Bacterial contamination and ineffective disinfection of personal protective equipment in medical centers pose potential health risks to patients and medical staff. The contamination burden of lead aprons and a reliable disinfection strategy are unknown.

METHODS

Ten routinely used, unsterilized lead aprons from a high-volume catheterization laboratory were studied. Standard and bacteria-resistant outer fabrics were included. Swabbings from four locations on each apron (inner thyroid collar, chest, waist, and bottom border) were obtained at baseline and after a 15-minute decontamination cycle using the UV-C based DCab System (Nosocom Solutions). Colony counts, speciation, and antibiotic resistance were obtained from aerobic and anaerobic cultures.

RESULTS

Baseline cultures grew ≥1 colony from 25 of 40 samples (62.5%; 310 colonies; 0-100 colonies/sample; 16 organisms), mainly skin and mouth flora without antibiotic resistance. Baseline growth was greatest from the thyroid collar and similar between different fabrics. UV-C reduced subsequent growth (7.8 ± 23.8 colonies overall vs 0.1 ± 0.3 colonies overall; P<.001), with all four isolates considered contaminants of laboratory handling. Colony counts were reduced in thyroid collar, chest, waist, nylon fabric, polyurethane fabric, and alternative bacteria-resistant fabric subgroups (all P<.05).

CONCLUSIONS

Routinely used lead aprons in a high-volume catheterization laboratory were contaminated by non-pathogenic skin and mouth flora located predominantly on the thyroid collar. Disinfection using an automated UV-C based system is highly effective across different apron surface locations and fabric types.

Bacterial contamination of medical uniforms: a cross-sectional study from Suzhou city, China

Few studies have been conducted which evaluate the prevalence of contamination of medical uniforms in China. The present study was designed to explore the characteristics of uniform contamination and associated factors. A total of 120 participants were enrolled in the study and 122 uniforms were sampled. Each uniform was sampled at three different sites to determine the colonisation of microorganisms. A total of 366 swab samples were cultured; 294 (80.3%) samples yielded various microorganisms and 75(61.5%) uniforms were contaminated with bacteria. The uniforms of medical students had the highest prevalence of contamination. The cuffs of uniforms were the most easily infected with bacteria. Participants who wiped their hands at the back of uniforms had higher contamination rate in the hanging part of uniforms. Our study demonstrated that medical uniforms can harbour microorganisms. Proper handling of medical uniforms and adequate education to medical staffs are required to decrease healthcare-associated infections.

Uniforms a 'breeding ground'

Your online story on uniforms harbouring antibiotic-resistant bugs (see news page 9 ) makes me wonder about precautions.

Laundering habits of student nurses and correlation with the presence of Staphylococcus aureus on nursing scrub tops pre- and postlaundering

Little is known about student nurse laundering practices. Student nurses swabbed their scrub tops after clinical and after laundering, and they completed a laundry survey; 13.5% of students wore the same scrub more than once, and few followed recommended guidelines by using hot water (20%) or bleach (5.6%) when laundering scrubs. After clinical shifts, 17% of swabs tested positive for Staphylococcus aureus; however, laundering eradicated it from 64.3% of positive samples. This was not statistically significant.

The Gown-glove Interface Is a Source of Contamination: A Comparative Study

BACKGROUND

The original Charnley-type negative-pressure body exhaust suit reduced infection rates in randomized trials of total joint arthroplasty (TJA) decades ago. However, modern positive-pressure surgical helmet systems have not shown similar benefit, and several recent studies have raised the question of whether these gowning systems result in increased wound contamination and infections. The gown-glove interface may be one source of particle contamination.

QUESTIONS/PURPOSES

The purpose of this study was to compare particle contamination at the gown-glove interface in several modern surgical helmet systems and conventional surgical gowns.

METHODS

A 5-μm fluorescent powder was evenly applied to both hands to the level of the wrist flexion crease. After gowning in the standard fashion, the acting surgeon performed a 20-minute simulated TJA protocol. Each of the five gowning systems was run through five trials. The amount of gown contamination at the gown-glove interface then was measured by three observers under ultraviolet light using a grading scale from 0 (no contamination) to 4 (gross contamination). Statistical analysis was carried out with Minitab 15. Friedman's test was used to compare the levels of contamination across trials for each gown and the Mann-Whitney test was used post hoc to perform a pairwise comparison of each gown.

RESULTS

All gown-glove interfaces showed some contamination. Friedman's test showed that there was a significant difference in contamination between gowns (p = 0.029). The Stryker T5 Zipper Toga system showed more contamination than the other gowns. The median contamination score and range for each gowning setup was 1.8 (range, 1-4; conventional Kimberly-Clark MicroCool gown without helmet), 4 (range, 3-4; Stryker T5 Zipper Toga), 3.6 (range, 0-4; Stryker helmet with conventional gown), 1.6 (range, 0-2; Stryker Flyte Toga), and 3.0 (range, 2-3; DePuy Toga). A Mann-Whitney test found no difference among any of the gowns except for the Stryker T5 Zipper Toga, which showed more contamination compared directly with each of the other four gowns (p < 0.001 for each gown-to-gown comparison).

CONCLUSIONS

Particle contamination occurs at the gown-glove interface in most commonly used positive-pressure surgical helmet systems. The Stryker T5 Zipper Toga exhibited more contamination than each of the other gowning systems.

CLINICAL RELEVANCE

The gown-glove interface is prone to particle contamination and all surgeons should be aware of this area as a potential source of surgical site infection. Although future studies are needed to clarify the link between particle contamination through this route and clinical infection, surgeons should consider using gowning systems that minimize the migration of fomites through the gown-glove interface.

Role of healthcare apparel and other healthcare textiles in the transmission of pathogens: a review of the literature

Healthcare workers (HCWs) wear uniforms, such as scrubs and lab coats, for several reasons: (1) to identify themselves as hospital personnel to their patients and employers; (2) to display professionalism; and (3) to provide barrier protection for street clothes from unexpected exposures during the work shift. A growing body of evidence suggests that HCWs' apparel is often contaminated with micro-organisms or pathogens that can cause infections or illnesses. While the majority of scrubs and lab coats are still made of the same traditional textiles used to make street clothes, new evidence suggests that current innovative textiles function as an engineering control, minimizing the acquisition, retention and transmission of infectious pathogens by reducing the levels of bioburden and microbial sustainability. This paper summarizes recent literature on the role of apparel worn in healthcare settings in the acquisition and transmission of healthcare-associated pathogens. It proposes solutions or technological interventions that can reduce the risk of transmission of micro-organisms that are associated with the healthcare environment. Healthcare apparel is the emerging frontier in epidemiologically important environmental surfaces.

Airborne Dispersal as a Novel Transmission Route of Coagulase-Negatwe Staphylococci Interaction Between Coagulase-Negative Staphylococci and Rhinovirus Infection

Objective:

To investigate whether rhinovirus infection leads to increased airborne dispersal of coagulase-negative staphylococci (CoNS).

Design:

Prospective nonrandomized intervention trial.

Setting:

Wake Forest University School of Medicine, Winston-Salem, North Carolina.

Participants:

Twelve nasalStaphylococcus aureus-CoNS carriers among 685 students screened forS. aureusnasal carriage.

Interventions:

Participants were studied for airborne dispersal of CoNS in a chamber under three conditions (street clothes, sterile gown with a mask, and sterile gown without a mask). After 2 days of pre-exposure measurements, volunteers were inoculated with a rhinovirus and observed for 14 days. Daily quantitative nasal and skin cultures for CoNS and nasal cultures for rhinovirus were performed. In addition, assessment of cold symptoms was performed daily, mucous samples were collected, and serum titers before and after rhinovirus inoculation were obtained. Sneezing, coughing, and talking events were recorded during chamber sessions.

Results:

All participants had at least one nasal wash positive for rhinovirus and 10 developed a symptomatic cold. Postexposure, there was a twofold increase in airborne CoNS (P= .0004), peaking at day 12. CoNS dispersal was reduced by wearing a gown (57% reduction,P< .0001), but not a mask (P= .7). Nasal and skin CoNS colonization increased after rhinovirus infection (P<.05).

Conclusions:

We believe this is the first demonstration that a viral pathogen in the upper airways can increase airborne dispersal of CoNS in nasalS. aureuscarriers. Gowns, gloves, and caps had a protective effect, whereas wearing a mask did not further reduce airborne spread.

Environment and body contamination: a comparison of two different removal methods in three types of personal protective clothing

BACKGROUND

This study aimed to examine the body contamination rates and environmental contamination levels during the removal of 3 types of personal protective clothing (PPC) by the individual accustomed removal method (IARM) and gown removal methods recommended by the Centers for Disease Control and Prevention (CDC).

METHODS

Fifty participants performed IARM and CDC-recommended gown removal methods to remove 3 types of PPC (ie, cotton gown, water resistant gown, and plastic apron) in random order at 2 separate sessions after applying Glo Germ simulated germ lotion on the gown's surface. A video demonstrating the CDC-recommended gown removal method was shown between the 2 sessions. After PPC removal, fluorescent stains were counted by an ultraviolet scan under dim light.

RESULTS

Following IARM, contaminants were splashed in the surroundings, particularly on the front part of the subject. The plastic apron and cotton gown obtained the highest and lowest contaminative hazards, respectively, to the hands, shoes, and environment. Females, nurses, and senior staff had serious hand or shoe contamination. The CDC removal method more significantly reduced body and environmental contamination of small fluorescent stains (<1 cm(2)), but not of large patches (>1 cm(2)), than IARM.

CONCLUSION

The effect of gown removal, PPC type, discarding PPC location, training of infection control measures, hand hygiene, and special work shoes should be considered daily.

Differential laundering practices of white coats and scrubs among health care professionals

The role played by health care worker's uniforms on the horizontal transmission of organisms within the hospital is still controversial. To determine the differential laundering practices in regards to white coats and scrubs, we surveyed physicians present at the 3 weekly academic conferences with largest attendance at our hospital (medicine, pediatrics, and anesthesiology). Out of 160 providers, white coats were washed every 12.4 ± 1.1 days and scrubs every 1.7 ± 0.1 days (mean ± standard error; P < .001). Faculty physicians washed their scrubs more frequently than house staff (1.0 vs 1.9 days, respectively, P = .018), and no differences were observed among specialties.

Associations between bacterial contamination of health care workers' hands and contamination of white coats and scrubs

BACKGROUND

Uniforms are potential reservoirs for hospital organisms, potentially reinfecting the hands of health care workers (HCWs). The study aimed to determine the association between the bacterial contamination of HCWs' hands and uniforms (white coats and scrubs).

METHODS

HCWs working in 5 intensive care units had cultures obtained from their hands and uniforms (white coats or scrubs). Pathogens were defined as any gram-negative bacilli, Staphylococcus aureus, and enterococci.

RESULTS

Bacterial growth was detected on 103 hands (86%); 13 (11%) grew S aureus, 7 (6%) grew Acinetobacter spp, 2 (2%) grew enterococci, and 83 (70%) grew only skin flora. The presence of pathogens on the hands was associated with a greater likelihood of the presence of pathogens on white coats (κ = 0.81; P < .001), but not on scrubs (κ = 0.31; P = .036). Similarly, the presence of Acinetobacter on HCWs' hands was associated with a greater likelihood of Acinetobacter contamination of white coats (κ = 0.70; P < .001), but not of scrubs (κ = 0.36; P = .024).

CONCLUSIONS

Contamination of provider's hands with pathogens or Acinetobacter baumannii was associated with contamination of white coats. This association was not observed between hands and scrubs, however.

The bacterial contamination of surgical scrubs

To our knowledge, no study has examined the bacterial profile of residents' scrubs. The goal of this investigation was to determine the bacterial profile of worn and unworn resident scrubs. Thirty pairs of scrubs were swabbed in 10 predetermined locations both prior to and after being worn continuously by the on-call resident. All swabs were screened for aerobic gram-positive and gram-negative bacteria. Bacteria underwent antimicrobial resistance testing and genetic relatedness by pulsed-field gel electrophoresis. Forty-one percent (123) of unworn scrub samples yielded bacteria, compared with 89% (268) of post-call scrub samples. On unworn scrubs, the most common organisms were coagulase-negative Staphylococcus (CNS; 94), gram positive rods (GPR; 34) and Streptococcus viridians (8). On post-call scrubs, the most common bacteria were CNS (271), micrococcus (51), Staphylococcus aureus (33), and GPR (28). All S. aureus were methicillin susceptible. There were different species, pulse-field types and antibiotic resistance profiles found amongst the CNS identified. No scrubs were found to harbor multidrug-resistant (MDR) organisms. This study found that unworn scrubs harbored normal skin flora and scrubs worn for at least 24 hours have a higher burden of bacteria than unworn scrubs but not an increased incidence of contamination with MDR organisms.

[The evaluation of bacteria penetration by medical textiles for multiple use and disposable multilayer surgical drapes, according to the PN-EN ISO 22610 standard]

INTRODUCTION

Cotton as well as synthetic textile medical products are widely used as barrier materials and individual protection against displacement of biological infectious factors. The required level of protection of these products for multiple use and disposable multilayer laminates against the penetration of microbes depends on the risk connected with type of surgical procedure defined in normative documents. METHODS. Cotton and syntetic medical textiles for multiple use, 30-times subjected to processes simulating conditions of the use as well as disposable multilayer surgical drapes were tested. Resistance to microbial wet penetration was conducted according to the PN-EN ISO 22610: 2007 standard.

RESULTS

The barrier of cotton fabrics was reduced after first washing and then systematically grew after each often cycles to the value close to the value at the beginning. From the twentieth cycle of simulated conditions of the use, barrier index was reduced. The barrier of the synthetic textile stayed on the average level, while multilayer disposable products ensured the full impermeability for the bacteria.

CONCLUSIONS

Natural cotton textiles for multiple use could be apply on operative blocks in limited range because of the changes of the cotton structure caused by repeated laundering process and sterilization. Synthetic materials also have limited application, although are more resistant to cleaning and sterilization processes. Disposable synthetic laminates with many layers use guarantee impermeability for bacteria and may be applied in operative blocks without restrictions.

The effect of silver impregnation of surgical scrub suits on surface bacterial contamination

Silver-impregnated fabrics are widely used for their antibacterial and antifungal effects, including for clinical clothing such as surgical scrub suits (scrubs). This study investigated whether silver impregnation reduces surface bacterial contamination of surgical scrubs during use in a veterinary hospital. Using agar contact plates, abdominal and lumbar areas of silver-impregnated nylon or polyester/cotton scrubs were sampled for surface bacterial contamination before (0 h) and after 4 and 8 h of use. The number of bacterial colonies on each contact plate was counted after 24 and 48 h incubation at 37 °C. Standard basic descriptive statistics and mixed-effects linear regression were used to investigate the association of possible predictors of the level of bacterial contamination of the scrubs with surface bacterial counts.

Silver-impregnated scrubs had significantly lowered bacterial colony counts (BCC) at 0 h compared with polyester/cotton scrubs. However, after 4 and 8 h of wear, silver impregnation had no effect on BCC. Scrub tops with higher BCC at 0 h had significantly higher BCC at 4 and 8 h, suggesting that contamination present at 0 h persisted during wear. Sampling from the lumbar area was associated with lower BCC at all three time points. Other factors (contamination of the scrub top with a medication/drug, restraint of patients, working in the anaesthesia recovery area) also affected BCC at some time points. Silver impregnation appeared to be ineffective in reducing bacterial contamination of scrubs during use in a veterinary hospital.

Patients' preference for physician attire: a survey of patients in family medicine training practices

BACKGROUND

Conflicting evidence exists about how patients would like their doctors to dress. This is complicated by new evidence showing elements of common physician attire (white coat or ties) can be contaminated with pathogens.

METHODS

We conducted a survey on a convenience sample of adult patients in three academic primary care offices in South Carolina and Ohio during the summer of 2010. The survey asked about patient preferences for physician attire and how their doctor usually dressed. After a brief statement regarding evidence of microbial contamination of coats and ties, the preferences were reexamined.

RESULTS

A total of 432 patients participated in the survey. No clear preference was stated by patients, and patients' initial preference was not closely related to their own physicians' customary attire. After reading the statement about microbial contamination, a significant percentage of patients changed their preference to select categories that did not include a tie or a white coat and tie. This information was associated with a large shift in preference to having physicians wear dress shirts and slacks with no tie (from 16% to 41%).

CONCLUSIONS

Patients in these three academic family medicine practices did not show any consistent preference for their physicians' attire. However, providing information about potential microbial contamination of clothing was associated with a shift in patient preferences for physicians not wearing a tie and a white coat.

Clinical Science Investigation (CSI) Canterbury: surgical gown length and blood inside gumboots

BACKGROUND

A gap between the bottom of gowns and the top of gumboots (commonly known as wellingtons or rubber boots outside of New Zealand) makes it possible for blood splashes to enter surgeons' gumboots and contact skin, putting them at risk of exposure to HBV, HCV and HIV. This study investigated the prevalence of blood splashes inside gumboots used by surgical staff at a single hospital.

METHOD

Ninety-four pairs of gumboots (91 from male surgeons, 3 from female surgeons) from the hospital operating theatres were used in this study. Each pair of boots was visually inspected for internal contamination with blood. Possible stains were checked using urine dipsticks to confirm the presence of blood.

RESULTS

Of the 94 pairs of gumboots checked, 55 pairs (58.5%) had blood staining on the inside lining. Eighty percent of blood stains were larger than 20 mm². None of the female surgeons' gumboots were contaminated compared to 60% of the males' pairs.

COCNLUSION

A large proportion of the gumboots used in operating theatres were contaminated internally with blood. The results of this study suggest that longer gowns should be available to health care workers in operating theatres to reduce internal contamination of gumboots and minimise the chance of exposure to body fluids.

[The estimation of penetrating of microbes by the protective clothing and textile medical devices, according to obligatory norms]

Textile medical products can be widely used as barrier materials and individual protection against biological threats. Rules of introducing such products to market are regulated by the Directive 93/42/ EEC. Detailed requirements and testing methods of textile medical products are presented in obligatory norms. The required level of protection of these products against the penetration of microbes depends on the risk connected with planned type surgical procedure, the duration of the surgical intervention, risks of bleeding or presences of other body liquids of the patient and susceptibilities of the patient to infection. The aim of the study was to establish resistance of medical textiles to wet bacterial penetration. Materials were examined by the apparatus dedicated to this type of testing and obtained results were rated with reference to obligatory contracted requirements. assured Textiles laminated with foils possessed best protective proprieties, whereas medical products made from the cotton do not provide the sufficient level of the protection against microbes.

Which regions of the operating gown should be considered most sterile?

Various guidelines have been proposed regarding which portions of a surgical gown may be considered sterile. Unfortunately, the validity of these recommendations has not been definitively established. We therefore evaluated gown sterility after major spinal surgery to assess the legitimacy of these guidelines. We used sterile culture swabs to obtain samples of gown fronts at 6-inch increments and at the elbow creases of 50 gowns at the end of 29 spinal operations. Another 50 gowns were swabbed immediately after they were applied to serve as negative controls. Bacterial growth was assessed using semiquantitative plating techniques on a nonselective, broad-spectrum media. Contamination was observed at all locations of the gown with rates ranging from 6% to 48%. Compared with the negative controls, the contamination rates were greater at levels 24 inches or less and 48 inches or more relative to the ground and at the elbow creases. The section between the chest and operative field had the lowest contamination rates. Based on these results, we consider the region between the chest and operative field to be the most sterile and any contact with the gown outside this area, including the elbow creases, should be avoided to reduce the risk of infection.

[Study on the testing methods to determine the resistance to wet bacterial penetration about surgical gowns and drapes]

The essay introduces the study on the performance monitoring tests for the resistance to wet bacterial penetration about surgical gowns and surgical drapes in accordance with ISO 22610.

Comparison of glove donning techniques for the likelihood of gown contamination. An infection control study

The creation of an optimal environment, whenever major joints are opened or metal is implanted into bone, is important to reduce infection following orthopaedic surgery. Following normal hand washing protocols, it is possible that pathogenic bacteria can remain on the skin. These bacteria may inadvertently be transferred to the surgical gown during the glove donning procedure and therefore contamination of the surgical wound could follow. We aimed to determine whether there is a difference between three differing glove donning techniques, open, closed and scrub staff assisted, in terms of accidental gown contamination, as the optimum method is unknown. Three differing glove donning techniques were assessed using ultra-violet (UV) lotion, applied to the hands after the scrub, to demonstrate patches of contamination on the surgical gowns. Two studies were carried out. An initial pilot study with theatre personnel and the main study by a single surgeon rehearsed in the various techniques. The region and size of contamination patches were documented. In the pilot study 12 out of 13 individuals were seen to have patches of UV fluorescent gown contamination following an observed scrub. In the main study, both the open and closed technique had a 100% gown contamination rate. This was concentrated around the cuff region. There were no contamination patches in the scrub staff assisted technique. Glove donning, using the scrub staff assisted technique can minimise the possibility of gown contamination. This is important in surgical procedures where the results of infection can be devastating.

Uniform: an evidence review of the microbiological significance of uniforms and uniform policy in the prevention and control of healthcare-associated infections. Report to the Department of Health (England)

A systematic search and quality assessment of published literature was conducted to establish current knowledge on the role of healthcare workers uniforms' as vehicles for the transfer of healthcare-associated infections. This review comprised a systematic search of national and international guidance, published literature and data on recent advances in laundry technology and processes. We found only a small number of relevant studies that provided limited evidence directly related to the decontamination of uniforms. Studies concerning domestic laundry processes are small scale and largely observational. Current practice and guidance for laundering uniforms is extrapolated from studies of industrial hospital linen processing. Healthcare workers' uniforms, including white coats, become progressively contaminated in use with bacteria of low pathogenicity from the wearer and of mixed pathogenicity from the clinical environment and patients. The hypothesis that uniforms/clothing could be a vehicle for the transmission of infections is not supported by existing evidence. All components of the laundering process contribute to the removal or killing of micro-organisms on fabric. There is no robust evidence of a difference in efficacy of decontamination of uniforms/clothing between industrial and domestic laundry processes, or that the home laundering of uniforms provides inadequate decontamination.

Construction: a model program for infection control compliance

ISSUE

In the 21st century, one of the most challenging tasks for the infection control practitioner (ICP) is establishing collegiality and trust with contractors, architects, maintenance and engineering personnel. We describe how an urban teaching hospital's infection control program cooperated with contractors during a large demolition, construction, and renovation project in order to protect its large population of immunosuppressed patients.

PROJECT

Most contractors are not accustomed to taking special precautions during demolition. Because of a previous Aspergillus outbreak in our heart transplant population, we already had an established infection control (IC) training program for contractors. We expanded and codified it in response to a major hospital renovation. The IC, in-house Design and Construction, and outside contractors meet before the initiation of all major renovation projects to anticipate IC concerns and proactively plan for infection control interventions. Now, all contractors and maintenance staff are required to receive IC training at the time of their employment. A hospital identification badge with attached sticker that indicates the IC training date is required. Infection Control Risk Assessments (ICRA) are initiated by project managers and completed jointly with IC. The ICPs make rounds on all projects at least weekly and large projects are visited daily. We established a team comprised of ICP, project manager, construction manager, and area nurse manager to monitor and make recommendations for improvement continually during the project. Staff are educated about construction so they can help monitor airflow and cleanliness.

RESULTS

Our contractors are more compliant with our IC specifications since they now understand why we insist on them. Through the years of major construction, the workers have jumped on the bandwagon. It is not unusual for construction or maintenance staff to contact IC for advice. There were four years of extensive construction without any hospital acquired Aspergillus infections. In the 5th year, after a neighboring institution started demolition and new construction, we identified two possible nosocomial infections and took immediate steps to make more corrections. There have been no further infections.

LESSONS LEARNED

The IC compliance is based on trust, education, and on-going monitoring. Proactive education and collaboration lead to long-term relationships, trust and patient safety.

OBJECTIVE

This article describes how a large teaching hospital's infection prevention program achieved compliance from contractors during a large renovation.

Preventive effects of various types of footwear and cleaning methods on dermatophyte adhesion

Tinea pedis is contagious and typically spreads from infected to non-infected persons. The purpose of this study was to evaluate the efficacy of footwear in preventing tinea pedis adhesion. Using the stamp culture method, we investigated the effectiveness of preventing dermatophyte passage by the wearing of stockings made of nylon, socks made of cotton and tabi (Japanese socks), as well as the effect of removing dermatophytes from these items by washing with soap, cold water and cold water after turning inside-out. For sandals, sneakers and boots, we also investigated the effect of dermatophyte removal by pouring cold water into the footwear, wiping with a wet towel, and pouring boiling water into the footwear. The wearing of socks or tabi was effective in preventing passage of dermatophytes. The stocking material proved to be too thin to prevent passage. On the inner side of socks (the side of the sole), all treatments were effective at removing dermatophytes, but on the outer side of socks (the side touching the surface of the sandals), the treatment of washing in cold water after turning inside-out resulted in significantly more dermatophytes as compared with the other treatments. Pouring cold water, wiping with a wet towel and pouring boiling water were all effective for removing dermatophytes from sandals and sneakers. However, for boots, the treatment of pouring cold water was less effective. To prevent the adhesion of dermatophytes to sandals, wearing socks or tabi was effective, and the treatments of washing socks in cold water after turning inside-out and of pouring cold water into the boots were less effective than the others.

Transfer of bacteria between biomaterials surfaces in the operating room—An experimental study

Bacterial adhesion to and transfer between surfaces is a complicated process. With regard to the success of biomaterials implants, studies on bacterial adhesion and transfer should not be confined to biomaterials surfaces in the human body, but also encompass surfaces in the operating room, where the origin of many biomaterials related infections is found. The purpose of this study was to quantify the transfer of Staphylococcus aureus, Staphylococcus epidermidis, and Propionibacterium acnes from one operating room material to another, while accounting for surface hydrophobicity and roughness, moistness and application of friction during transfer. The tested operating room materials were gloves, broaches (orthopaedic drills), theatre gowns, and light handles. As a possible clinical intervention method to prevent transfer, it was investigated whether dipping the gloves in a chlorhexidine splash-basin affected the viability of the transferred bacteria. Transfer (moist and without friction) was demonstrated to some extent with all bacterial strains and with every material, ranging from 17% to 71%, and was influenced by the bacterial strain, moistness of the inoculum, the application of friction, and the characteristics of both the donating and the receiving surface. Dipping the glove material in 4% or 0.4% chlorhexidine solutions killed all bacteria present, regardless of whether surfaces were dried or moist and thus prevented transfer.

A cover up? Potential risks of wearing theatre clothing outside theatre

A report from the Hospital Infection Society Working Group (2002) examined ritualistic practices in theatre and evidence was sought to establish which practices could be supported with clear scientific evidence. The report stated that there is little or no research to show that wearing theatre attire outside the theatre and returning without changing into clean theatre attire increases wound infection rates. It is difficult to implement infection control practices on a scientific basis as there is often a lack of evidence to support the practice. Moreover, many practices are grounded in 'this is the way things are done around here' (Ward 2000).

The role of gowns in preventing nosocomial transmission of methicillin-resistant Staphylococcus aureus (MRSA): gown use in MRSA control

During a 2-year period, a standard isolation protocol for control of methicillin-resistant Staphylococcus aureus was compared with a similar protocol in which gowns were not used but the availability of alcohol-based hand disinfectant was increased. Intervention wards had 0.10 fewer new MRSA transmissions per ward per month, compared with control wards (P was not significant).

Hospital gowns as a vehicle for bacterial dissemination in an intensive care unit

The microbiota from the uniforms of 31 professionals from the general intensive care unit was analyzed. The samples were collected in duplicate at the beginning and at the end of the work period. Total viable counts of microorganisms were determined; there was a significant increase in the counts at the end of the period, when compared with those obtained at the beginning. No significant difference was observed between the first and second counts obtained from the cuffs. However, differences were observed for the samples from the abdominal region. Among the isolated pathogens 11/18 were Staphylococcus aureus, 2/18 were Acinetobacter baumannii, 2/18 were Klebsiela pneumoniae and 1/18 were Serratia rubidae. Some of these isolates were multi-resistant to antibiotics. Emphasis should be placed on reducing the spread of these pathogens in the hospital, making sure that biosafety protocols are followed by the staff.

HOME- VERSUS HOSPITAL-LAUNDERED SCRUBS

PURPOSE

To determine the presence of pathogens on scrub attire that had been either laundered at home or in the hospital.

STUDY DESIGN AND METHODS

Quasi-experimental research design with a convenience sample. The left front shoulders of home-laundered scrubs (n = 30) and hospital-laundered scrubs (n = 20) were cultured during the first 2 hours of a single workday. For the home-laundered scrubs, data were collected concerning home washing procedures, water temperature, pets in the home, and donning procedures.

RESULTS

No pathogenic growth was found on either the hospital- or home-laundered scrubs. In addition, no relationships were found between home washing procedures, water temperature, pets in the home, and donning procedures.

CLINICAL IMPLICATIONS

The results of this pilot study suggested that scrubs laundered both at home and in the hospital were free of pathogens, and that differing home washing procedures made no difference. Further investigation is necessary with larger numbers of subjects.

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Polishing of dental prostheses can cause a dangerous cycle of cross-contamination involving dentists, laboratory technicians, patients and auxiliary personnel. The aim of this study was to show the microbial contamination in the dental laboratory during the polishing procedure of complete dentures. For this purpose, 4 experiments were conducted. Experiment I - Determination of the total colony-forming units (CFU) counts contaminating complete maxillary dentures. During the polishing procedure, determination of the CFU counts transferred to the operator (Experiment II) and of the total CFU counts transferred to previously sterilized complete dentures (Experiment III). Experiment IV - The total counts of remaining CFU in the lathe spindle after Experiments II and III. Complete dentures were highly contaminated (mean = 1.4 x 10(7) CFU/mL). There was a elevated level of contamination by splatter and aerosols. There was high microbial transfer from the contaminated lathe spindle to the sterile prostheses (mean = 1.7 x 10(7) CFU/mL). The spindles were highly contaminated after polishing procedures (mean = 3.5 x 10(8) CFU/mL). The polishing of dental prostheses is a possible source of transmission of communicable diseases in the laboratory and requires improved techniques for infection control.

The role of covering gowns in reducing rates of bacterial contamination of scrub suits

OBJECTIVE

This study was undertaken to determine whether covering gowns reduce the rates of contamination of surgical scrubs.

STUDY DESIGN

Seventy-five clinicians had pieces of fabric from clean scrubs attached to two areas of their scrub suits. Participants wore a covering garment when wearing scrub suits off of designated areas (n = 25), did not wear a covering garment (n = 25), or wore scrub suits outside the hospital (n = 25). Subsequently, the fabric was assessed with culture in enhanced broth media and blood agar.

RESULTS

Although there was a trend toward lower rates of contamination in the group that did not wear a covering garment, the difference was not significant. At no point, and at neither site of fabric attachment, did those who wore a covering garment demonstrate any advantage in regard to levels or frequency of contamination.

CONCLUSION

Wearing covering garments over scrub suits does not reduce rates of contamination.

Modern cleanroom clothing systems: people as a contamination source

Today, clothing and clothing systems for cleanrooms are mainly tested with regard to material properties such as particle generation, particle filtration, and resistance to wear. The dispersal chamber or "body-box" has been used for studying the protective efficacy of clothing systems in use, for example by Hoborn in 1981 (1) and Whyte and Bailey in 1985. A modified dispersal chamber has recently been installed at KTH. Tests and comparative studies have been performed in the dispersal chamber on selected clothing systems. The latest tests have been performed in two parts. In Part 1, each person performed 12 sequences dressed in new, modern cleanroom clothing systems with small variations, such as with and without goggles, different face masks, and different sizes of hoods. In Part 2, each person performed six test sequences with new, modern cleanroom clothing systems with variations in fabrics, and as a comparison, two sequences with pharmaceutical clothing system and surgical clothing system, respectively. The results are given in total number of airborne particles (> or = 0.5 microm per cubic meter) and airborne aerobic CFU per cubic meter. Statistical evaluations of the results have been performed. The source strengths of the contamination source people wearing modern cleanroom clothing systems have been estimated.

Contaminated operating room boots: the potential for infection

BACKGROUND

Dirty operating room boots, often contaminated with blood and other infected material, are not only a source of discontent among surgeons and other surgical personnel, but they also pose a potential risk of transmission of viral or bacterial diseases to the wearer and cleaner of the boots.

METHOD

Operating room boots were examined for the presence of blood by visual inspection; the presence or absence of blood was confirmed by a specific biochemical test. Bacterial isolation and quantification from boots were performed with conventional methodology.

RESULTS

In this study, a spot check revealed that 44% of all operating room boots tested were contaminated with blood and that the majority were contaminated with bacteria. Sixty-three percent of surgeons using the facility had blood-contaminated boots, and a significant number of boots belonging to other surgical personnel were also contaminated with blood and bacteria normally associated with skin microbiota or the environment. Comfort shoes with perforations on their upper surface and plastic boots commonly found in operating rooms were most heavily contaminated, whereas Wellington boots and clogs had less contamination.

CONCLUSION

The present practice of manual cleaning of boots is unsatisfactory, and it is recommended that boots be washed in automatic washing machines.

Direct measurement of bacterial penetration through surgical gowns: a new method

There is a paucity of data on the penetration of bacteria through surgical gowns during operations. A simple new method was developed, using Petri dishes filled with horse blood agar that were attached to the outside of the gown material. This was used to assess bacterial penetration through disposable spun-bonded polyester gowns and re-usable woven polyester gowns during normal use. There was a significant difference between the two gown types when tested in the axilla (P = 0.02), the groin (P = 0.02) and the peri-anal region (P < 0.01), with the disposable gowns performing to a higher standard. Re-usable gowns demonstrated variation in penetrability, and for this reason, may be unsuitable for use in orthopaedic implant surgery.

Contamination of gowns, gloves, and stethoscopes with vancomycin-resistant enterococci

OBJECTIVE

[corrected] To measure directly the rate of contamination, during routine patient examination, of gowns, gloves, and stethoscopes with vancomycin-resistant enterococci (VRE).

SETTING

A large, academic, tertiary-care hospital.

PATIENTS

Between January 1997 and December 1998, 49 patients colonized or infected with VRE were entered in the study.

DESIGN

After routine examination, the examiner's glove fingertips, gown (the umbilical region and the cuffs), and stethoscope diaphragm were pressed onto Columbia colistin-nalidixic acid (CNA) agar plates with 5% sheep blood plus vancomycin 6 pg/mL. The stethoscope diaphragm was sampled again after cleaning with a 70% isopropanol wipe.

RESULTS

VRE were isolated from at least 1 examiner site (gloves, gowns, or stethoscope) in 33 (67%) of 49 cases. Gloves were contaminated in 63%, gowns in 37%, and stethoscopes in 31%. All three items were positive for VRE in 24%. One case each had stethoscope and gown contamination without glove contamination. Only 1 (2%) of 49 stethoscopes was positive after wiping with an alcohol swab. Contamination at any site was more likely when the patient had a colostomy or ileostomy. Patients identified by rectal-swab culture alone were as likely to contaminate their examiners as were those identified by clinical specimens.

CONCLUSIONS

Our study revealed a high rate of examiner contamination with VRE. The similar risk of contamination identified by surveillance and clinical cases reinforces concerns that patients not known to be colonized with VRE could serve as sources for dissemination. Wiping with alcohol is effective in decontaminating stethoscopes.

Isolation and characterization of methicillin-resistant Staphylococcus aureus strains from nares of nurses and their gowns

The isolation and characterization of methicillin-resistant Staphylococcus aures (MRSA) strains from the bilateral nares of nurses and their gowns are described. MRSA strains could be isolated from eigth of fifty bilateral nares of nurses and two of their gowns. Ten MRSA strains were typed using coagulase typing, and divided into two types, coagulase II and III. In this study, we found a new group (producing toxic shock syndrome toxin -1, coagulase III and staphylococcal enterotoxin C) in Japanese MRSA. Furthermore, we confirmed that MRSA strains originating from bilateral nares of three nurses were identical and two strains isolated from the left naris of one nurse and her gown were also identical by pulsed-field gel electrophoresis.

Monte Carlo studies for irradiation process planning at the Portuguese gamma irradiation facility

The paper describes a Monte Carlo study for planning the irradiation of test samples for microbiological validation of distinct products in the Portuguese Gamma Irradiation Facility. Three different irradiation geometries have been used. Simulated and experimental results are compared and good agreement is observed. It is shown that Monte Carlo simulation improves process understanding, predicts absorbed dose distributions and calculates dose uniformity in different products. Based on these results, irradiation planning of the product can be performed.

Bacterial flora on the white coats of medical students

This study has demonstrated that the white coats of medical students are more likely to be bacteriologically contaminated at points of frequent contact, such as the sleeve and pocket. The organisms identified were principally skin commensals including Staphylococcus aureus. The cleanliness of the coat as perceived by the student was correlated with bacteriological contamination, yet despite this, a significant proportion of students only laundered their coats occassionally. This study supports the view that the students' white coat is a potential source of cross infection on the ward and its design should be modified in order to facilitate hand washing. Hospitals training medical students should consider taking on the burden of providing freshly laundered white coats for the students.