Article

Molecular epidemiology of microbial contamination in the operating room environment: Is there a risk for infection?

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Abstract

Modern operating rooms are considered to be aseptic environments. The use of surgical mask, frequent air exchanges, and architectural barriers are used to reduce airborne microbial populations. Breaks in surgical technique, host contamination, or hematogenous seeding are suggested as causal factors in these infections. This study implicates contamination of the operating room air as an additional etiology of infection. To investigate the potential sources of perioperative contamination, an innovative in situ air-sampling analysis was conducted during an 18-month period involving 70 separate vascular surgical procedures. Air-sample cultures were obtained from multiple points within the operating room, ranging from 0.5 to 4 m from the surgical wound. Selected microbial clonality was determined by pulse-field gel electrophoresis. In a separate series of studies microbial nasopharyngeal shedding was evaluated under controlled environmental conditions in the presence and absence of a surgical mask. Coagulase-negative staphylococci were recovered from 86% of air samples, 51% from within 0.5 m of the surgical wound, whereas Staphylococcus aureus was recovered from 64% of air samples, 39% within 0.5 m from the wound. Anterior nares swabs were obtained from 11 members of the vascular team, clonality was observed between 8 strains of S epidermidis, and 2 strains of S aureus were recovered from selected team members and air-samples collected throughout the operating room environment. Miscellaneous Gram-negative isolates were recovered less frequently (<33%); however, 7 isolates expressed multiple patterns of antimicrobial resistance. The traditional surgical mask demonstrated limited effectiveness at curtailing microbial shedding, especially during symptomatic periods of rhinorrhea. Gram-positive staphylococcal isolates were frequently isolated from air samples obtained throughout the operating room, including areas adjacent to the operative field. Nasopharyngeal shedding from person participating in the operation was identified as the source of many of these airborne contaminants. Failure of the traditional surgical mask to prevent microbial shedding is likely associated with an increased risk of perioperative contamination of biomedical implants, especially in procedures lasting longer than 90 minutes.

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... 37 Using pulsed-field gel electrophoresis, researchers recovered strains of coagulase-negative staphylococci and S aureus in air samples from the OR and linked these microorganisms to the operating team despite all staff members wearing surgical face masks. 39 Similarly, evidence has shown that bacterial shedding can occur through surgical scrub attire. 38 ...
... 45,46 Investigators studying intraoperative microbial contamination during 70 vascular surgery procedures found that 35% to 50% of the time they could detect S aureus or S epidermidis in the OR room air less than one meter from the surgical incision. 39 Seminal research has demonstrated that approximately 300 million squamous skin cells are released into the air each day per person, 30% of which can carry bacteria. ...
... Until the exudative and proliferative phases of wound healing are complete, the incisional edges are not fully sealed and the surgical incision remains vulnerable to exogenous bacterial contamination from the environment and substandard wound care. 39,54,88 For example, lumbar spinal fusion surgery incisions may be close to the buttocks and perineum, and contamination from bedpans and commodes can pose an infection risk. Body fluids, including blood and serum, that collect in the incision can provide a rich growth medium for any contaminating organisms. ...
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Surgical site infections (SSIs) are among the most common and expensive of all health care–associated infections, and as many as 50% are considered preventable. Surgical care bundles, which involve a small set of reliably performed evidence-based practices, may effectively reduce SSI rates. However, closure of the surgical incision is one aspect of surgical care that is not well described in current SSI prevention bundles; this presents an opportunity for perioperative professionals to improve care by identifying and implementing evidence-based incision closure practices for high-risk procedures (eg, colorectal surgery). We propose and review the evidence supporting a colorectal incision closure bundle composed of a glove and sterile instrument set change, irrigation with 0.05% chlorhexidine solution, use of triclosan-coated sutures, removal of surgical drapes after applying postoperative dressings, use of topical skin adhesive or an antiseptic dressing, and distribution of comprehensive postoperative patient instructions. © 2018 The Authors. AORN Journal published by Wiley Periodicals, Inc. on behalf of Association of periOperative Registered Nurses.
... Air related controls, as maintaining positive air pressure, air recirculation, use of HEPA air filters and controls for both temperature and humidity [2]. Several studies have already reported bacterial presence in C-section ORs using culture-dependent methods, pulse-field gel electrophoresis, fluorescent particle counting, and adenosine triphosphate (ATP) testing [3][4][5][6]. As humans lack natural ventilation during their stay in operating rooms, and, regardless of the efficacy of cleaning and the use of filtered air, they are expected to shed skin bacteria and thus enriched the environment with human bacteria [3,[7][8][9]. ...
... Several studies have already reported bacterial presence in C-section ORs using culture-dependent methods, pulse-field gel electrophoresis, fluorescent particle counting, and adenosine triphosphate (ATP) testing [3][4][5][6]. As humans lack natural ventilation during their stay in operating rooms, and, regardless of the efficacy of cleaning and the use of filtered air, they are expected to shed skin bacteria and thus enriched the environment with human bacteria [3,[7][8][9]. ...
... Humans shed up to 37 million bacterial genomes into the environment per hour [10]. It has been shown that C-section babies have a higher abundance of skin-like bacteria (Staphylococcus, Corynebacterium, and Propionibacterium) at birth [11], which can also be acquired from the OR [3]. Previous studies using culture-dependent methods also showed that over 85% of air samples from OR's had skin-like bacteria, which were mostly coagulase-negative Staphylococci and Corynebacterium [3]. ...
Article
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Bacteria found in operating rooms (ORs) might be clinically relevant since they could pose a threat to patients. In addition, C-sections operations are performed in ORs that provide the first environment and bacterial exposure to the sterile newborns that are extracted directly from the uterus to the OR air. Considering that at least one third of neonates in the US are born via C-section delivery (and more than 50% of all deliveries in some countries), understanding the distribution of bacterial diversity in ORs is critical to better understanding the contribution of the OR microbiota to C-section-associated inflammatory diseases. Here, we mapped the bacteria contained in an OR after a procedure was performed; we sampled grids of 60x60 cm across walls and wall-adjacent floors and sequenced the V4 region of 16S rRNA gene from 260 samples. The results indicate that bacterial communities changed significantly (ANOSIM, p-value < 0.001) with wall height, with an associated reduction of alpha diversity (t-test, p-value <0.05). OR walls contained high proportions of Proteobac-teria, Firmicutes, and Actinobacteria, with Proteobacteria and Bacteroidetes being the highest in floors and lowest in the highest wall sites. Members of Firmicutes, Deinococcus-thermus, and Actinobacteria increased with wall height. Source-track analysis estimate that human skin is the major source contributing to bacterial composition in the OR walls, with an increase of bacteria related to human feces in the lowest walls and airborne bacteria in the highest wall sites. The results show that bacterial exposure in ORs varies spatially, and evidence exposure of C-section born neonates to human bacteria that remain on the floors and walls, possibly accumulated from patients, health, and cleaning staff.
... 2,3 Thus the working environment in dental clinics is filled with lots of splatters and aerosols, and they can transmit microorganisms from patients or clinical materials to workers. 4 Even, a study showed a facial contamination with bacteria after aerosol-producing treatment, in which 5.6 cfu/m 3 of bacteria were detected on the worker's nares after 90-minute treatments, despite of using protective masks. 5 Furthemore, such a splash exposure was extremely high in dental healthcare professionals, 87.9% for dentists and 88.6% for dental hygienists, while the rate of nurses was approximately half (42.9%). 6 Therefore, dental healthcare workers face a significant risk of bacterial exposure and occupational infection. ...
... Similar to our results, S aureus was reported as the organism commonly found most on the dental professionals' apron sleeves, and moreover it contaminated the 50%-75% of the dental staffs' clothing. 5,12 Moreover, 52.4% the of dental prosthetic patients were reported to have S aureus around their appliances, 37 and 60% of the dental procedures can create aerosols of S aureus. 5 Therefore, given its colonization in dental patients' oral cavities, S aureus in the current study is supposed to be aerosolized during oral treatment, floated generally in the air of clinics, and subsequently transmitted into the lip cosmetic samples through the body of the subjects, dental hygienists. ...
... 5,12 Moreover, 52.4% the of dental prosthetic patients were reported to have S aureus around their appliances, 37 and 60% of the dental procedures can create aerosols of S aureus. 5 Therefore, given its colonization in dental patients' oral cavities, S aureus in the current study is supposed to be aerosolized during oral treatment, floated generally in the air of clinics, and subsequently transmitted into the lip cosmetic samples through the body of the subjects, dental hygienists. ...
Article
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Objectives In dental clinics, dental hygienists are exposed to aerosolized pathologic bacteria, which can be transmitted to the oral cavity via lip cosmetics. Accordingly, such contamination poses a consistent health risk among staffs. Our study examined the bacterial contamination of lip cosmetics used by dental hygienists while in a clinic setting. Methods Sixteen dental hygienists were surveyed regarding their job assignments and habits associated with lip cosmetic. Subsequently, microorganisms were analyzed in collected samples of the hygienists' lip cosmetics using colony‐forming unit (CFU) assays, 16s‐rDNA polymerase chain reaction, and DNA sequencing. Results Notably, 81.3% of the submitted lip cosmetic samples were contaminated, with bacterial CFUs ranging from undetectable to innumerable. Many samples (43.8%) exceeded the microbial limits of cosmetic contamination. Of the lip cosmetic used for more than 6 months, 60% exceeded the microbial limit. When wearing a mask every time, only one of the six samples exceeded the microbial limit. More frequent dental mask changing was associated with a lower likelihood that the cosmetic sample would exceed the microbial limit. No samples from hygienists who changed their masks four times a day exceeded the microbial limit, compared to 33.3% from hygienists who only changed the mask when it became wet. Most isolated bacteria were gram‐positive, facultative anaerobic, asporogenic, and opportunistically pathogenic, and the most prevalent species were Staphylococcus aureus, Streptococcus salivarius, and Staphylococcus epidermidis. Conclusion Our findings indicate that dental staff, including dental hygienists, should exercise more careful workplace habits, particularly with regard to infection control and cosmetic use.
... [17][18][19][20][21][22][23] A study supporting this assertion documented the recovery of the same molecular strains of coagulase-negative staphylococci and S aureus recovered from OR air samples, originating from nasopharyngeal shedding by members of the surgical team during the same surgical cases. 24 The shedding of bacteria into the air by the OR team members can be enhanced by conditions including dermatitis and upper respiratory infections. 15,25,26 A study published in 1984 in the Journal of Bone and Joint Surgery documented that conversations within the OR during total joint arthroplasty enhanced microbial contamination of the OR air. ...
... 27 These findings have validated a more recent study, which documented that the barrier properties of the traditional surgical mask rapid decreases due in part to the accumulation of moisture within the fabric of the mask leading to nasopharyngeal venting along the edges of the mask. 24 Underscored the impact of contaminated air on postoperative surgical infection are the recent global reports of intraoperative wound contamination by Mycobacterium chimaera. 28 These infections, which continue to be reported, have been found to be the result of air contamination associated with a commonly used heater cooler unit in cardiothoracic surgical procedures, despite use of ultraclean air ventilation. ...
Article
In the modern operating room (OR), traditional surgical mask, frequent air exchanges, and architectural barriers are viewed as effective in reducing airborne microbial populations. Intraoperative sampling of airborne particulates is rarely performed in the OR because of technical difficulties associated with sampling methodologies and a common belief that airborne contamination is infrequently associated with surgical site infections (SSIs). Recent studies suggest that viable airborne particulates are readily disseminated throughout the OR, placing patients at risk for postoperative SSI. In 2017, virtually all surgical disciplines are engaged in the implantation of selective biomedical devices, and these implants have been documented to be at high risk for intraoperative contamination. Approximately 1.2 million arthroplasties are performed annually in the United States, and that number is expected to increase to 3.8 million by the year 2030. The incidence of periprosthetic joint infection is perceived to be low (<2.5%); however, the personal and fiscal morbidity is significant. Although the pharmaceutic and computer industries enforce stringent air quality standards on their manufacturing processes, there is currently no U.S. standard for acceptable air quality within the OR environment. This review documents the contribution of air contamination to the etiology of periprosthetic joint infection, and evidence for selective innovative strategies to reduce the risk of intraoperative microbial aerosols.
... There is abundant evidence that airborne particles are potential carriers of pathogenic bacteria [10][11][12]. Particles contaminating operating room air may be an additional potential cause of SSI [13]. Although the association between airborne particles and microbes is still debated, electronic particle counting can be considered an objective parameter of the efficacy of air filtering and recirculation systems in operating rooms [14]. ...
... Although the association between airborne particles and microbes is still debated, electronic particle counting can be considered an objective parameter of the efficacy of air filtering and recirculation systems in operating rooms [14]. Operating room air quality is important, and is directly linked to proper room ventilation and air filtration [15], which is in turn relevant for the reduction of airborne particulate [13]. ...
Article
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Surgical site infections are the second major cause of hospital acquired infections, accounting for a large part of overall annual medical costs. Airborne particulate is known to be a potential carrier of pathogenic bacteria. We assessed a mobile air particle filter unit for improvement of air quality in an operating room (OR). A new mobile air decontamination and recirculation unit, equipped with a crystalline ultraviolet C (Illuvia® 500 UV) reactor and a HEPA filter, was tested in an OR. Airborne particulate was monitored in four consecutive phases: I) device OFF and OR at rest; II) device OFF and OR in operation; III) device ON and OR in operation; IV) device OFF and OR in operation. We used a particle counter to measure airborne particles of different sizes: ≥0.3, ≥0.5, ≥1, ≥3, ≥5, >10 µm. Activation of the device (phases III) produced a significant reduction (p < 0.05) in airborne particulate of all sizes. Switching the device OFF (phase IV) led to a statistically significant increase (p < 0.05) in the number of particles of most sizes: ≥0.3, ≥0.5, ≥1, ≥3 µm. The device significantly reduced airborne particulate in the OR, improving air quality and possibly lowering the probability of surgical site infections.
... Microbial contamination of operating theatres has greatly contributed in precipitating the prevalence of hospital acquired infections, HAIs [1]. The burden of microbial contamination of operating theatres ranges from 4 to 37.4% pre and post operation [2][3][4], with an average of 11.5% pre-operation in Africa [5]. About 10% of these infections are responsible for adverse patient outcomes including increased mortality, increased length of stay of about 4-7 days among others [6]. ...
... The most implicated bacteria in operating theatre contamination include staphylococcus species accounting for about 40% [2,3,5] followed by Enterobacter and E. coli [5]. If the operating theatres are not sufficiently sterilized, surgical site infections are most likely to increase leading to poorer prognostic outcomes of patients post-surgery [10,11] . ...
Article
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Background: Microbial contamination of hospital environment, especially in operating theatres (OT) and other specialized units has greatly contributed to continuous and multiple exposure to nosocomial infections by patients and the public. We purposed to assess microbial contamination of operating theatres and antibacterial sensitivity pattern of bacteria isolated from theatres of Mbale Regional Referral Hospital, Eastern Uganda. Methods: We employed a laboratory based cross-sectional study design. Swabbing of different surfaces and settle plate establishment in 4 various operating theatres was carried out. A total of 109 samples were collected, 31 air samples and 78 swabs from four operating theatres. Samples were collected in the mornings after disinfection prior to start of daily operations. Antibacterial sensitivity testing of isolated bacterial pathogens was performed by Kirby Bauer disc diffusion method following standard operating procedure. Colony counts for the settle plates were carried out using a colony counter. Results: All the four theatres had their mean colony counts exceeding the acceptable limit of 5 cfu/dm2/h. Gynaecology theatre had up to 261 cfu/dm2/h and Ophthalmology operating theatre had approximately 43 cfu/ dm2/h. A total of 14 different organisms were isolated with Pseudomonas spp. [23.9%]; Bacillus spp. [17.5%] and Aspergillus spp. [15.8%] being the most common contaminants respectively. Other isolates included Enterococcus spp., Rhizopus spp. and Coagulate Negative Staphylococcus isolates especially from settle plates. Most bacterial isolates showed considerable resistance to antibacterial agents. Pseudomonas spp. was resistant to chloramphenicol (53.6%) and cotrimoxazole (57.1%). Most of the bacterial pathogens were sensitive to imipenem [83.3%]. Conclusions: There is moderate contamination of operating theatres of Mbale Regional Referral Hospital. Common organisms were Pseudomonas, Bacillus, and Aspergillus spps. Resistance was observed against chloramphenicol and cotrimoxazole. More caution is necessary to carefully disinfect the operating theatres at Regional referral settings and similar tertiary health care centres with more emphasis on obstetrics and gynecology theatres. Diagnosis and care of patients at such clinical settings should consider the possibility of antibiotic resistance. Keywords: Microbial pathogens, Operating theatre, Antimicrobial pattern
... (2)(3)(4)(5) due to SSI, patients may suffer with delayed wound healing, prolongs hospitalization, it increases morbidity and the overall costs for the treatment (6)(7)(8). Various supplies have been accounted for as being in charge of the tainting of the OT, including unfiltered air, ventilation frameworks and germicide arrangements, waste of the injuries, transportation of patients and accumulation packs, careful group, degree of indoor traffic, theater outfit, foot products, gloves and hands, utilization of insufficiently disinfected gear, defiled condition and terribly polluted surfaces (2,4,(9)(10)(11)(12)(13)(14). The study reported that the major pathogens associated with infection of implantable biomedical devices are Staphylococcus aureus and the coagulase negative staphylococci (CoNS) (9). ...
... Various supplies have been accounted for as being in charge of the tainting of the OT, including unfiltered air, ventilation frameworks and germicide arrangements, waste of the injuries, transportation of patients and accumulation packs, careful group, degree of indoor traffic, theater outfit, foot products, gloves and hands, utilization of insufficiently disinfected gear, defiled condition and terribly polluted surfaces (2,4,(9)(10)(11)(12)(13)(14). The study reported that the major pathogens associated with infection of implantable biomedical devices are Staphylococcus aureus and the coagulase negative staphylococci (CoNS) (9). Few studies reported that the clinical implication of microbial contamination in the OT is enormous on both the patient and the caring surgical team (2,4,5) About 10% of all infections may have a serious burden to patients, i.e. increased morbidity, mortality and prolongs hospitalization and overall costs (15). ...
... showed highest percentage of occurrence. In addition, Edmiston, et al. (2005) found that, Coagulase-negative staphylococci recovered from 86% of air samples, whereas Staphylococcus aureus recovered from 64% of air samples. Moreover, Munoz-Price, et al. (2012), concluded that, Thirty-four floor areas were cultured, including 22 at baseline and 12 at follow-up; pathogens were isolated from 63% and 66% of floor areas, respectively (P = .917). ...
... There was microbial growth in approximately one quarter of post-preparation samples. In addition, Edmiston, et al. (2005) found that Coagulase-negative staphylococci were recovered 51% from within 0.5 m of the surgical wound, whereas Staphylococcus aureus was recovered 39% within 0.5 m from the wound. ...
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ARTICLE INFO ABSTRACT Background: Surgical asepsis practices should maintained by the surgical team to prevent contamination of the open surgical wound. Aim: This study aimed to evaluate the surgical asepsis practices in the operating theatre of King Khalid Hospital, Najran. Methods: The researchers utilized a three data collection forms to collect the needed data about practices of surgical asepsis. Swabs obtained from surgical site and from OR surfaces for bacteriological examination. Results: only 55% of patients showered the day of surgery, there was no cleaning of light and scrubbing sinks at 60% and 75% of surgeries respectively. Sterile persons touch only sterile items at 55% of surgeries, 84.9% of them performed surgical scrubbing correctly. There was a contamination of OR floor and conditioning system in 55% of surgeries, there was a surgical site infection(SSI) after suturing among 40% of patients and there was a correlation between contamination of scrubbing taps and SSI post-preparation (P < 0.05). Conclusion: There was an improper surgical asepsis practices performed by OR surgical team, we recommend the importance of continuing education among OR staff to keep them updated with the new trends and developments in surgical asepsis.
... 14 Transmission of bacteria which might occur within the healthcare environment has significant clinical implications for infection control practices within the operating room environment. 15 The findings that coagulase negative staphylococcus was most frequently isolated from both the operating room and surgical wards air was also reported by other workers. 12,15 A linear relationship between air counts of bacteria in operating rooms and surgical site infection or wound contamination rate has been reported by many investigators. ...
... 15 The findings that coagulase negative staphylococcus was most frequently isolated from both the operating room and surgical wards air was also reported by other workers. 12,15 A linear relationship between air counts of bacteria in operating rooms and surgical site infection or wound contamination rate has been reported by many investigators. 16,17 Whyte et al. 16 suggested that settle plates showing bacterial surface contamination represents a more relevant indicator of the wound contamination rate than air counts. ...
Article
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Bacterial airborne contamination and other fomites in the operating theatre is a major cause of nosocomial infection. This study was to evaluate the bacterial and fungal pathogens contaminating the air and protective wears in the theatre and surgical wards of two tertiary hospitals in Kano. The air sampling in the operating theatre and surgical wards were done forth nightly on 30 occasions by settle plate technique. The theatre gown was sampled by sweep plate method while samples from the face mask and hand gloves were collected by swabbing large representative areas. Isolation and identification of bacterial and fungal pathogens were carried out by standard microbiological procedure. Six bacteria genera and 2 fungi specie were observed in the theatre air while 9 bacteria genera and 2 fungi specie were observed from the ward air. Also 7 bacteria genera were observed on face mask, theatre gown and hand gloves respectively after surgery. Bacterial counts obtained by exposed plates was high after 2hrs, while an increased count was also observed 1hr after the presence of visitors in the evenings in the surgical wards. Nosocomial pathogens were identified during the research. This portends danger for surgical site infection patients.
... Further observation regarding the species of microorganisms revealed that after filter replacement, there was a decrease of 23% in coagulase-negative Staphylococci, which were found to be present during 76.75% of surgeries, while gram-negative bacteria were present in 9.0% of the cases. Edmiston et al. (2005)found that Staphylococci and gram-negative bacteria were present in 86% and 33% of cases, respectively. Coagulase-negative Staphylococci are among the most commonly identified microorganisms in surgical site infections (Edmiston et al., 2005;Becker et al., 2014).According to Dolinger et al. (2010), most orthopedic implant-related infections are due to gram-positive aerobic bacteria, predominantly S. aureus and S. epidermidis (44% to 50%). ...
... Edmiston et al. (2005)found that Staphylococci and gram-negative bacteria were present in 86% and 33% of cases, respectively. Coagulase-negative Staphylococci are among the most commonly identified microorganisms in surgical site infections (Edmiston et al., 2005;Becker et al., 2014).According to Dolinger et al. (2010), most orthopedic implant-related infections are due to gram-positive aerobic bacteria, predominantly S. aureus and S. epidermidis (44% to 50%). These microorganisms form biofilms on the surfaces of prostheses and implants, thereby providing resistance to antibiotics. ...
Article
The aim of this study was to assess the impact of ventilation and filtration conditions on particle concentrations in an orthopedic operating room. Total particle, viable particle, and CO2 concentration were measured under three different situations, namely before air filter replacement, after air filter replacement, and in an operating room with a new air conditioning system. Before air filter replacement, the mean values of airflow, total particle concentration, and viable particle concentration were 706 m3/h, 15.0 × 106 ± 4.0 × 106 particles/m3, and 57 CFU/m3, respectively. After replacement, the airflow increased to 1954 m3/h, and total and viable particle concentrations decreased to 0.4 × 106 ± 0.2 × 106 particles/m3 and 24 CFU/m3, respectively. In the room with a new air conditioning system, the airflow was 2051 m3/h, and total and viable particle concentrations were 0.3 × 106. ± 0.1 × 106 particles/m3 and 15 CFU/m3, respectively. The CO2 levels were 663 ppm (before), 659 ppm (after), and 574 ppm (new room). The results showed that inappropriate or no maintenance of filters in an air conditioning system had significant negative effects on indoor air quality in operating rooms. Air conditioning systems operating with saturated filters can be affected by pressure drop, which can lead to a reduction in airflow, thereby resulting in an increase in the average total particle and viable particle concentrations and the risk of infection in operating rooms. However, the results showed that the CO2 concentration was not affected by the filter replacement.
... Factors responsible for bacterial contamination in OT units can be classified into two, external and internal. The external factors includes the air quality system/ventilation, design of the units, occupancy density, traffic and activities within the units and door opening rate [2, 3 11 ], while the internal factors includes, colonization/infection of the health care personnel/patient, contaminated surface and equipment used routinely, and air quality within the units [16,17] .similarly, the rate of surgical site infections have been linked with the level of microbial load(microbial colony unit) [4] . To reduce intraoperative bacterial contamination, proper design and ventilation system and behavioral measure needs to be adopted within the units, particularly the use of appropriate protective attire and limited medical activists [1,17,18] Indoor air quality within the units plays a crucial role in the contamination level, because the airborne microbial concentration and particle mass is directly related to human activity, number of people and type of clothing worn by the health care personnel and patients within the units. ...
Article
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Bacterial contamination of operating theater is a major risk factor for increased incidence of surgical site and nosocomial infections in hospitals. Surveillance study allows for minimizing incidence and implements effective control and preventive measures. This study assessed the bacterial contamination level, bacterial pathogens and their resistance pattern in the two operating theaters in our hospitals.150 specimens were collected from two operating theaters, Main (MOT)(n=80) and Obsteristic and Gyneacology (O&G OT)(n=70) based on pre-identified inanimate items/surfaces and designated points and analyzed using standard microbiological methods. Overall bacterial contamination rate was 56.7%, 40% in MOT and 75.7% in O&G OT. High contamination rate of Staphylococcus aureus, coagulase negative staphylococci and Bacillius spp were recorded in both units. Clinically relevant pathogens, Klebsiella spp, Enterobacter spp, Enterococcus spp, Pseudomonas aeruginosa were recovered from routinely used equipments, with more pathogens from the O&G OT. High resistant to cotrimoxazole, amoxicillin, ampicillin-clauvanic acid, streptomycin, gentamycin, and erythromycin, observed with bacterial isolates from O/G OT. While the findings portray the level of bacterial contamination within the units, the high rate within the O&G OT posses greater risk for postoperative infections, necessitating need for effective cleaning and disinfection practices and adherence to basic standard infection procedures
... The problem of microbiological contamination of air is associated with many different types of premises, including university rooms, offices, laboratories, canteens as well as healthcare centres and hospitals (13)(14)(15)(16)(17). This problem becomes even more severe when it can affect the health of people dwelling in such premises, as in the case of healthcare units and hospitals. ...
Article
Objectives: This study was aimed to assess the concentration of microbial aerosol and species composition of airborne staphylococci in 10 healthcare facilities in southern Poland including primary healthcare units and hospital wards; and to assess whether the selected components of microbial aerosol pose a threat of severe infections to either patients or the personnel. Methods: The study was conducted at monthly intervals over a period of one year. Air samples were collected by MAS-100 sampler. The number of mesophilic bacteria, mould fungi, actinomycetes and staphylococci was determined on general and selective media. The species identification of staphylococci was conducted using API tests for strains that were pre-selected based on macroscopic and microscopic observations. Results: A total number of 1,584 samples were collected during the sampling period. The numbers of airborne microorganisms varied between the examined premises and between the seasons of the year. The observed differences were statistically significant with one exception for actinomycetes and their differences between the examined premises. The concentrations of mesophilic bacteria varied from 5 to 297 CFU/m3 of air, for Staphylococcus the values ranged from 1 to 96 CFU/m3, for fungi - from 1 to 100 CFU/m3, and the number of actinomycetes ranged from 7 to 321 CFU/m3. Ten species of coagulase-negative staphylococci (CoNS) were identified among 55 isolates with S. saprophyticus and S. warneri being the most frequently detected (n = 14 and 13, respectively). S. haemolyticus, which is one of the most common causal agents of nosocomial infections was observed in four facilities (n = 5). Conclusions: The microbial concentrations varied both between the seasons of the year and between the examined facilities. The highest bioaerosol concentrations were observed in most crowded premises. The identified species of staphylococci, although not typically associated with human infections, are common causal agents of nosocomial infections and infections in immunocompromised people.
... A particularly pernicious and challenging one to address has been that of the contaminated environment. Whyte et al. (1982) and Edmiston et al. (2005) have described the general link between airborne contamination and SSIs, with an estimated 30-98% of wound bacteria attributable to airborne contaminants, depending on the ventilation system in an operating room. In higher income countries, invasive procedures are typically performed by scrub-attired personnel striving to reduce contamination in operating rooms with meticulously filtered air. ...
... Prior studies have suggested that environmental contamination in the operating room can frequently result in positive bacterial PCR results of air samples in what were otherwise considered sterile cases. 13 We also believe there is a potential for contamination from skin flora during tissue handling or passage of instruments through arthroscopic portals. Several sources of control specimens were therefore selected to evaluate the rate of positivity due to environmental contamination for our specific PCR assay in conditions typically seen throughout an ACLR procedure. ...
... These systems have proven effective at further reducing environmental contamination [32][33][34][35] but are inherently limited by the episodic nature of their operation and, in some cases, compliance with manual application. It has been repeatedly demonstrated that active shedding by OR staff represents a potential source of contamination in the OR [36][37][38][39][40][41][42][43] and this shedding during a case cannot be addressed real-time by episodic disinfection. This is of particular concern in surgical procedures involving an implant as research has shown the microbial inoculum associated with infection is far smaller in the presence of a foreign body than in other clean surgical wounds. ...
Article
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Background: A growing body of research has demonstrated that manual cleaning and disinfection of the operating room (OR) is suboptimal. Residual environmental contamination may pose an infection risk to the surgical wound. This study evaluates the impact of a visible-light continuous environmental disinfection (CED) system on microbial surface contamination and surgical site infections (SSI) in an OR. Methods: Samples from 25 surfaces within 2 contiguous ORs sharing an air supply were obtained after manual cleaning on multiple days before and after a visible-light CED system installation in 1 of the ORs. Samples were incubated and enumerated as total colony-forming units. SSIs in both ORs, and a distant OR, were tracked for 1 year prior to and 1 year after the visible-light CED system installation. Results: There was an 81% (P = .017) and 49% (P = .015) reduction in total colony-forming units after the visible-light CED system installation in the OR in which the system was installed, and in the contiguous OR, respectively. In the OR with the visible-light CED system, SSIs decreased from 1.4% in the year prior to installation to 0.4% following installation (P = .029). Conclusions: A visible-light CED system, used in conjunction with manual cleaning, resulted in significant reductions in both microbial surface contamination and SSIs in the OR.
... If the principal pathogens responsible for common cold, rhinitis, and influenza (rhinovirus, coronavirus, parainfluenza virus, influenza virus, respiratory syncytial virus) are generally not responsible for SSIs, other microorganisms are commonly associated with a viral respiratory disease: Staphylococcus aureus, coagulase-negative Staphylococcus, Streptococcus, Gram-negative bacteria, and methicillin-resistant S aureus (measuring 0.2-5 mm) can adhere to the condensation droplets to form colony forming units, and be infectious in short-range scenarios (less than 1 m), theoretically leading to SSIs. Operating room counts lower than 10 colony forming units are mandatory for knee and hip arthroplasty [35]. ...
... A particularly pernicious and challenging one to address has been that of the contaminated environment. Whyte et al. (1982) and Edmiston et al. (2005) have described the general link between airborne contamination and SSIs, with an estimated 30-98% of wound bacteria attributable to airborne contaminants, depending on the ventilation system in an operating room. In higher income countries, invasive procedures are typically performed by scrub-attired personnel striving to reduce contamination in operating rooms with meticulously filtered air. ...
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Surgery saves lives in traumas, obstetric emergencies, infections, oncology, and more. Indeed, 30% of the global disease burden requires surgical therapy, yet in lower middle-income countries, 5 billion people have little or no access to safe surgical care. At the same time, safety of surgical providers is a must, given the heavy burden of infections due to bodily fluid splashes in austere settings. Safe surgery—for both patients and providers—is thus a global health priority. SurgiBox, a joint project of MIT D-Lab, Massachusetts General Hospital, and the program EssentialTech Cooperation & Development Center EPFL, aims to develop, evaluate, and ultimately deploy a new technology to help increase access to safe surgery. SurgiBox shrinks the scope of the sterility challenge from the room to the critical space immediately over the incision. Users seal the modular system of sterile clear containers over the patient and operate via ports. An integrated airflow system controls enclosure conditions. Everything folds for rapid deployment. This project requires close dialogue among stakeholders with iterative, rapid prototyping changes. Benchtop and simulation testing to date demonstrate superior environmental control compared to standard operating rooms, notably including setup time, time to surgical site sterility, resistance to active contamination, and air changes per hour. Ongoing efforts include testing in stress use scenarios to replicate field conditions, field testing, in vivo testing, manufacturing, and mapping out a sustainable deployment and scale-up strategy.
... Prior studies have suggested that environmental contamination in the operating room can frequently result in positive bacterial PCR results of air samples in what were otherwise considered sterile cases. 13 We also believe there is a potential for contamination from skin flora during tissue handling or passage of instruments through arthroscopic portals. Several sources of control specimens were therefore selected to evaluate the rate of positivity due to environmental contamination for our specific PCR assay in conditions typically seen throughout an ACLR procedure. ...
Article
Purpose: To determine whether bacterial DNA will be detectable by polymerase chain reaction (PCR) in torn graft tissue at the time of revision anterior cruciate ligament reconstruction (ACLR). Methods: A total of 31 consecutive revision ACLR cases from 1 center from 2014-2016 were recruited. No patients had clinical signs of infection on presentation. Torn graft tissue was obtained in revision cases and subjected to clinical culture and PCR analysis with a universal bacterial primer. Fluorescence microscopy was used to confirm the presence of a biofilm. We obtained negative control samples of water open to air on the field and excess primary ACLR graft tissue, as well as torn native ligament, to evaluate for PCR positivity due to environmental contamination. Results: Clinical cultures were positive (coagulase-negative Staphylococcus) in 1 revision case (3%, 1 of 31). Bacterial DNA was detectable in most revision ACLR cases (87.0%, 27 of 31), and there was a low rate of PCR positivity in negative control samples of water open to air (0%, 0 of 3), excess primary ACLR graft tissue after passage (20%, 1 of 5), or native torn ligament (20%, 1 of 5). Bacterial biofilm presence on failed graft tissue as well as monofilament suture was visually confirmed with fluorescence microscopy. Conclusions: Bacterial DNA is frequently present in failed ACLR grafts, with high rates of DNA detection by PCR but low culture positivity. Level of evidence: Level IV, case series.
... 13 Edmiston et al. found that air samples taken adjacent to the operative field showed growth of both patho- genic and opportunistic organisms. 14 The relationship between air and surface contamination, and surgical site contamination, has also been demonstrated in more recent research. 15 The presence of patho- gens on surfaces has been shown to increase the contamination rates of healthcare workers' hands, both bare and gloved. ...
Article
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Background: Manual cleaning and disinfection of the operating room (OR) environment may be inadequate due to human error. No-touch technologies, such as pulsed-xenon ultraviolet light (PX-UV), can be used as an adjunct to manual cleaning processes to reduce surface contamination in the OR. This article reports the cumulative results from 23 hospitals across the United States that performed microbiologic validation of PX-UV disinfection after manual cleaning. Methods: We obtained samples from 732 high-touch surfaces in 136 ORs at 23 hospitals, after manual terminal cleaning, and again after PX-UV disinfection (n = 1464 surface samples). Samples were enumerated after incubation, and the results are reported as total colony-forming units (CFU). Results: The average CFU after manual cleaning ranged from 5.8 to 34.37, and after PX-UV, from 0.69 to 6.43. With manual cleaning alone, 67% of surfaces were still positive for CFUs; after PX-UV disinfection, that number decreased to 38% of all sampled surfaces-a 44% reduction. When comparing manual cleaning to PX-UV, the reduction in CFU count was statistically significant. Conclusion: When used after the manual cleaning process, the PX-UV device significantly reduced contamination on high-touch surfaces in the OR.
... Not surprisingly, these alarming numbers have led to countless efforts by health care professionals to identify and reduce the sources and risk factors of SSIs. Studies have identified numerous sources implicated in the transmission of pathogenic microbes including air [8] , hospital surfaces [9] , liquid nitrogen freezers [10] , computer keyboards [11] , stethoscopes [12] , staff uniforms [13] , tourniquets [14] and even leaving sterile trays open for too long [15] . ...
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BACKGROUND Surgical site infections are a major cause of morbidity and mortality following orthopedic surgery. Recent efforts to identify sources of contamination in the operating rooms have implicated mobile phones. AIM To investigate microbial colonization on the mobile phones of health care professionals in the orthopedic operating room. METHODS We conducted a cross-sectional study involving culture and sensitivity analysis of swabs taken from the mobile phones of orthopedic and anesthesia attendings, residents, technicians and nurses working in the orthopedic operating rooms over a period of two months. Demographic and cell phone related factors were recorded using a questionnaire and the factors associated with contamination were analyzed. RESULTS Ninety-three of 100 mobile phones were contaminated. Species isolated were Coagulase-negative Staphylococcus (62%), Micrococcus (41%) and Bacillus (26%). The risk of contamination was increased with mobile covers and cracked screens and decreased by cell phone cleaning. CONCLUSION Mobile phones belonging to health care workers are frequently contaminated with pathogenic bacteria with the potential of transferring drug resistance to nosocomial pathogens. Studies investigating the relationship to surgical site infections need to be conducted. The concept of “mobile hygiene” involving the change of mobile covers, replacement of cracked screens or even wiping the phone with an alcohol swab could yield the cost-effective balance that contaminated cell phones deserve until they are established as a direct cause of surgical site infections.
... The bacterial contamination of the open wound is deemed as the major cause of infections [2,3]. For instance, the Staphylococcus aureus (S. aureus) is the most common bacteria found in ORs that cause infections [4,5]. ...
Article
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Operating room (OR) ventilation plays an important role in mitigating the spread of bacteria-carrying particles (BCPs) and preventing the incidence of surgical site infections (SSIs). The use of surgical lamps in ORs is critical for patient safety and staff comfort. However, the surgical lamp serves as an obstruction in the ventilation airflow and also as a source of heat generation, which often creates a stagnant area under the lamp. Such a stagnant area is normally poorly ventilated, where a significant amount of BCPs can accumulate. As the lamp is usually positioned above the patient to illuminate the wound, the accumulation of airborne BCPs under the lamp leads to a high risk of infections and constitutes a threat to patient safety. Therefore, we proposed an innovative design of the surgical lamp, that is, the fan-mounted surgical lamp. The performance of this new design of lamp was compared with the conventional closed-shape lamp under two ventilation strategies: mixing and unidirectional airflow (UDF) ventilation. To account for different working conditions, both the horizontal and 45˚ orientations were applied to the lamps. We employed numerical simulations to predict the BCPs contamination in the proximity of the surgical site, as it is directly related to the risk of SSIs. The results showed that the fan-mounted lamp considerably reduced the level of contamination under both ventilation strategies. Results also suggested that the contamination level cannot be effectively reduced by only adjusting the orientation of the closed-shape lamp under unidirectional airflow ventilation.
... Our results indicated that these biological additives need to be carefully selected before application, as this might affect the colonization of the piglet gut microbiota. Previous studies using both culture-dependent and cultureindependent methods showed that there are complex microbial communities in the air [44,45]. However, the contribution of air bacteria to the colonization of the piglet gut was very low in our study. ...
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Background: The acquisition and development of the mammalian microbiome early in life are critical to establish a healthy host-microbiome symbiosis. The maternal and environmental microbial reservoirs are considered the main sources of microbial communities in newborn mammals. However, the timely relative contribution of various microbial sources to the colonization of the gut microbiota in newborn piglets remains unclear. The aim of this study was to investigate the influence of the sow and delivery environment microbes on nursing piglets from birth through weaning. Results: We longitudinally sampled the microbiota of 20 sow-piglet pairs (three piglets per sow) from multiple body sites and the surrounding weaning environment from birth to 28 days postpartum (1,119 samples in total) reared under identical conditions. Source-tracking analysis revealed that the contribution of various microbial sources to the piglet gut microbiome gradually changed over time. The neonatal microbiota was initially sparsely populated and predominantly comprised taxa from the maternal vaginal microbiota that increased gradually from 69.0% at day 0 to 89.3% at day 3 and dropped to 0.28% at day 28. As the piglets aged, the major microbiota community patterns were most strongly associated with the sow feces and slatted floor, with contributions increasing from 0.52% and 9.6% at day 0 to 62.1% and 33.8% at day 28, respectively. The intestinal microbial diversity, composition and function significantly changed as the piglets aged, and 30 age-discriminatory bacterial taxa were identified with distinctive time-dependent shifts in their relative abundance, which likely reflected the effect of the maternal and environmental microbial sources on the selection and adaptation of the piglet gut microbiota. Conclusions: Vaginal microbiota is the primary source of the gut microbiota in piglets within three days after birth and are gradually replaced by the sow fecal and slatted floor microbiota over time. These finding may offer novel strategies to promote the establishment of exogenous symbiotic microbes to improve piglet gut health.
... Additionally, high density of airborne CFUs was identified as a significant risk factor for infection. In recent years, elevated airborne particulate counts have become more frequently attributed to instrument contamination as well as surgical site and prosthetic infections [9,24,25,[27][28][29][30]. While the present study was unable to detect a difference in tray contamination between the Illuvia™ UV-C and the control group, this may be attributable to limitations in the number of trays and data collection in an ideal OR setting. ...
Article
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Introduction Postoperative infections represent a substantial burden to patients and healthcare systems. To improve patient care and reduce healthcare expenditures, interventions to reduce surgical infections must be employed. The crystalline C-band ultraviolet (UV-C) air filtration technology (Aerobiotix Inc., Miamisburg, OH, USA) has been designed to reduce airborne bioburden through high-quality filtration and germicidal irradiation. The purpose of this study was to assess the ability of a novel UV-C air filtration device to reduce airborne particle counts and contamination of surgical instrument trays in an operating room (OR) setting. Materials and methods Thirty sterile instrument trays were opened in a positive-air-flow OR. The trays were randomly assigned to one of two groups (UV-C or control, n=15 per group). In the UV-C group, the UV-C filtration device was used and in the control, it was not. All trays were opened with the use of a sterile technique and left exposed in the OR for four hours. Air was sampled by a particle counter to measure the numbers of 5µm and 10µm particles. Culture specimens were obtained from the trays to assess for bacterial contamination. Outcome data were collected at 30-minute intervals for the duration of the four-hour study period. Results Use of the UV-C device resulted in statistically significant reductions in the numbers of 5µm (average of 64.9% reduction when compared with the control, p<0.001) and 10µm (average of 65.7% reduction when compared with the control, p<0.001)-sized particles detectable in the OR. There was no significant difference in the overall rates of contamination (33.3% in the control group vs. 26.7% in the UV-C group, p=1.0) or the time to contamination (mean survival of 114 minutes in the control group vs. 105 minutes in the UV-C group, p=0.72) of surgical instrument trays with the use of the UV-C device. Conclusions The results demonstrate that the UV-C filtration device can successfully reduce airborne bioburden in standard ORs, suggesting that it may have the potential to reduce the risk for wound and hardware infections. Further clinical trials are necessary to better determine the effect of this air filtration system on postoperative infection rates.
... In line with the present study, earlier studies have shown the most common bacteria detected on the contaminated instruments had coagulase-negative Staphylococcus 60.4% (28) and 44% [16]. Because, coagulase-negative Staphylococcus were frequently isolated from air samples obtained throughout the OR, they were recovered from 86% of air samples [24]. ...
Article
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Background Covering the prepared sterile back tables (PSBTs) during periods of nonuse and during active surgeries may decrease contamination of sterile surgical instruments that have direct contact to surgical wound. The Association of periOperative Registered Nurses (AORN) declared that an easy method for covering and removing the drape will ultimately be most effective (e.g. standard two-drape method). Hence, this study was designed to test the hypothesis that using a novel single-drape cover had more efficiency and safety in decreasing airborne bacteria-carrying particles (ABCPs) settling on the PSBTs during static and dynamic periods than the standard two-drape method. Methods This experimental study was conducted with using 918 agar plates to detect contamination of the PSBTs with ABCPs on two conditions (static and dynamic) at an academic medical center in Kashan, Iran, from September 25, 2021, to January 20, 2022. The contamination of PSBTs was evaluated by 6 agar settle plates (n = 918 in total) on each PSBT in static and dynamic operating room (OR) conditions. At each time-point, this set-up was repeated on two occasions else during data collection, establishing 81 PSBTs in total. Tested groups included the PSBTs covered with the standard two-drape method, the novel single-drape cover, or no cover. The plates were collected after 15, 30, 45, 60, 120, 180, 240 min and 24 h. The primary outcome measured was comparison of mean bioburden of ABCPs settling on covered PSBTs on two conditions by using agar settle plates. The secondary outcomes measured were to determine the role of covering in decreasing contamination of PSBTs and the estimation of time-dependent surgical instrument contamination in the uncovered PSBTs on two conditions by using agar settle plates. Results Covering the PSBTs during static and dynamic OR conditions lead to a significantly decreased bioburden of ABCPs on them (P < 0.05). No differences were seen between the standard two-drape method and the novel single-drape cover (P > 0.05). Conclusions We found that there is no preference for using the novel single-drape cover than the standard two-drape method. Our results showed a significant decrease in bioburden of ABCPs on the PSBTs when those were covered during static and dynamic OR conditions, indicating the efficiency for covering the PSBTs during periods of nonuse and during active surgery.
... However, further studies should be conducted to confirm this hypothesis. Previous studies using both culture-dependent and culture-independent methods showed that there are complex microbial communities in the air (Edmiston et al., 2005;Emerson et al., 2017). However, the contribution of air bacteria to the colonization of the piglet gut was very low in our study. ...
Article
Full-text available
The acquisition and development of the mammalian microbiome early in life are critical to establish a healthy host-microbiome symbiosis. Despite recent advances in understanding microbial sources in infants, the relative contribution of various microbial sources to the colonization of the gut microbiota in pigs remains unclear. Here, we longitudinally sampled the microbiota of 20 sow-piglet pairs (three piglets per sow) reared under identical conditions from multiple body sites and the surrounding weaning environment from birth to 28 days postpartum (1,119 samples in total). Source-tracking analysis revealed that the contribution of various microbial sources to the piglet gut microbiome gradually changed over time. The neonatal microbiota was initially sparsely populated, and the predominant contribution was from the maternal vaginal microbiota that increased gradually from 69.0% at day 0 to 89.3% at day 3 and dropped to 0.28% at day 28. As the piglets aged, the major microbial community patterns were most strongly associated with the sow feces and slatted floor, with contributions increasing from 0.52 and 9.6% at day 0 to 62.1 and 33.8% at day 28, respectively. The intestinal microbial diversity, composition, and function significantly changed as the piglets aged, and 30 age-discriminatory bacterial taxa were identified with distinctive time-dependent shifts in their relative abundance, which likely reflected the effect of the maternal and environmental microbial sources on the selection and adaptation of the piglet gut microbiota. Overall, these data demonstrate that the vaginal microbiota is the primary source of the gut microbiota in piglets within 3 days after birth and are gradually replaced by the sow fecal and slatted floor microbiota over time. These findings may offer novel strategies to promote the establishment of exogenous symbiotic microbes to improve piglet gut health.
... SSI previously termed postoperative wound infection is defined as that infection presenting up to 30 days after a surgical procedure if no prosthetic is placed and up to 1 year if a prosthetic is implanted in the patient (5). SSI delays wound healing, prolongs hospitalization, increases morbidity and the overall costs [6][7]. Multiple reservoirs have been reported as being responsible for hospital contamination, particularly the operating theatre, including unfiltered air, ventilation systems, antiseptic solutions (2), drainage of the wounds, transportation of patients and collection bags, surgical team, extent of indoor traffic, theater gown, foot wares, gloves and hands, use of inadequately sterilized equipment, contaminated environment and grossly contaminated surfaces. ...
Article
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Surgical site infections (SSIs) are leading cause of morbidity and mortality in hospitals. Both the antimicrobial resistance and SSIs are the worst complications that directly affect a patient health and safety. The present investigation aimed to study bacterial contamination in operation rooms in Benghazi Medical Centre (BMC).Ninety seven swabs were collected from several parts of the operation theatre. The specimens were collected during the period from 2017-2018. Bacterial isolates were identified, and tested against common used antimicrobial agents the results revealed that the spread of bacterial contamination in operation room was 67%. All isolates from operation room were sensitive to imepenem ,azithromycin, levofloxacin, ciprofloxacin (100%) followed tobramycin,ceftazidime, gentamycin(66.67%) whereas, all isolates were resistant to cefexim, tetracyclin, carbencillin, septrin, cephalexin, augmentin, cefoxtin, cefuroxime sodium by (100%), on other hand, the rate of infection in surgical site was (75%), the most prevalent pathogens was Klebsiella pneumonia(16%) followed by Acinetobacter bummannii, Pseudomonas aerginosa and Staph aurues (12%) Protues mirablis (10%) Enterococus spp (8%) followed Enterobacter aerogenes (4%) Yersinia enterocolitica (2%). Obtained results showed that most of the isolates from surgical site were multidrug resistant to common used antimicrobials as well as suggest the importance of environmental and surface contamination control to prevent SSI.
... Pascals entre différentes zones constituent une barrière physique à l'entrée d'air dont le rôle est de réduire l'introduction de microorganismes dans la zone à protéger. Mais ces systèmes de maîtrise de la qualité de l'air peuvent en pratique être défaillants (panne, conditions climatiques particulières, travaux) et l'air des pièces normalement traité peut être contaminé et engendrer des infections ou des épidémies chez les patients hospitalisés (Lutz et al. 2003) (Edmiston et al. 2005) (Napoli et al. 2012). ...
Thesis
Les infections associées au soins (IAS) sont un problème majeur de santé publique, notamment du fait qu’elles participent à la menace mondiale que représente l’antibiorésistance qui devrait en 2050 causer 10 millions de décès par an et se placer comme la première cause de mortalité dans le monde. La forte consommation d’antibiotiques, la promiscuité et la vulnérabilité des patients font de l’hôpital un lieu privilégié pour la transmission de bactéries notamment résistantes aux antibiotiques, et pour les phénomènes épidémiques. Les surfaces de l’environnement hospitalier jouent un rôle important dans ces phénomènes, en servant de réservoir et de relais aux agents responsables d’IAS. Mieux connaitre la diffusion des bactéries responsables d’IAS sur les surfaces de soins apparait alors comme un axe majeur de recherche. Dans ce travail, afin d’observer la circulation et la persistance, sur les surfaces hospitalières, des bacilles à gram négatifs (BGN) responsables d’IAS, et d’identifier les raisons de la diffusion et du succès épidémique de certaines espèces bactériennes et sous-populations bactériennes responsables d’IAS, des prélèvements intensifs de surfaces, au total 5329, ont été réalisés. Deux sources de contamination des surfaces de l’environnement hospitalier ont été considérées : l’origine hydrique avec P. aeruginosa comme chef de file, et l’origine humaine avec les bactéries productrices de carbapénèmases (BPC).Ce travail nous a permis de collectionner 567 souches environnementales issues d’un échantillonnage de terrain. Pour chaque souche, des données clinico-éco-épidémiologiques ont été recueillies. Cette collection de souches isolées en conditions réelles est le socle de cette thèse et constitue toute son originalité. Elle nous a permis de tracer, au plus près des conditions réelles, les routes de transmission des bactéries responsables d’IAS sur les surfaces de soins. Ainsi nous avons pu identifier des réservoirs environnementaux de BGN et analyser la circulation entre l’eau du point d’eau, les surfaces de soins et les patients pour les bactéries d’origine hydrique, et entre les surfaces de soins et les patients pour les bactéries d’origine humaine. Lors de l’analyse de ces circulations sur les surfaces de soins, les différents niveaux de complexité de la diversité des populations et sous-populations bactériennes ont pu être intégrés. Considérer cette complexité dans sa globalité semble être la clef pour mieux comprendre le rôle de l’environnement de soins dans la transmission de bactéries responsables d’IAS et les phénomènes épidémiques. De plus ce travail, a démontré que l’environnement proche des patients était le reflet des bactéries colonisant/infectant les patients tout en apportant des informations supplémentaires sur sa diversité. Ainsi le patient au sein de son environnement de soins devrait être considéré comme une seule unité de transmission afin de mieux anticiper la diffusion des bactéries dans l’environnement de soins et les phénomènes épidémiques.
... Coagulase-negative Staphylococcus and Staphylococcus aureus were recovered from 86% and 64% of all samples, respectively, with Gram-negative bacteria recovered less frequently (33%). [57] Isolation of 100 colony-forming units per surface area sampled (CPSS) from the AWE is associated with increased probability of high-risk stopcock contamination events that are in turn associated with increased mortality. [15,16] A study by van Vlymen demonstrated that poor hand hygiene practices inadvertently cause tiny amounts of hepatitis C virus to be placed on the outside of a medication vial, leading to further contamination and infection. ...
Article
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Purpose of review: This review aims to highlight key factors in the perioperative environment that contribute to transmission of infectious pathogens, leading to healthcare-associated infection. This knowledge will provide anesthesia providers the tools to optimize preventive measures, with the goal of improved patient and provider safety. Recent findings: Over the past decade, much has been learned about the epidemiology of perioperative pathogen transmission. Patients, providers, and the environment serve as reservoirs of origin that contribute to infection development. Ongoing surveillance of pathogen transmission among these reservoirs is essential to ensure effective perioperative infection prevention. Summary: Recent work has proven the efficacy of a strategic approach for perioperative optimization of hand hygiene, environmental cleaning, patient decolonization, and intravascular catheter design and handling improvement protocols. This work, proven to generate substantial reductions in surgical site infections, can also be applied to aide prevention of SARS-CoV-2 spread in the COVID-19 era.
... Various studies demonstrate the importance of the airborne route of infection transmission in the hospital setting. 19 On one hand, it seems unreasonable to allow recirculation of return air into patient care environments. On the other hand, it seems reasonable to take advantage of the energy in the return air to dilute contamination through air recirculation, while ensuring that the return air is clean and comfortable. ...
Article
The outbreak of SARS-CoV-2 has made us all think critically about hospital indoor air quality and the approaches to remove, dilute, and disinfect pathogenic organisms from the hospital environment. While specific aspects of the coronavirus infectivity, spread, and its routes of transmission are still under rigorous investigation, it seems that a recollection of knowledge from the literature can provide useful lessons to cope with this new situation. As a result, a systematic literature review was conducted on the safety of air filtration and air recirculation in healthcare premises. This review targeted a wide range of evidence from codes and regulations, to peer-reviewed publications, and best practice standards. The literature search resulted in 394 publications, of which 109 documents were included in the final review. Overall, even though solid evidence to support current practice is very scarce, proper filtration remains one important approach to maintain the cleanliness of indoor air in hospitals. Given the rather large physical footprint of the filtration system, a range of short-term, and long term solutions from the literature are collected. Nonetheless, there is a need for a rigorous and feasible line of research in the area of air filtration and recirculation in healthcare facilities. Such efforts can enhance the performance of healthcare facilities under normal conditions or during a pandemic. Past innovations can be adopted for the new outbreak at low-to-minimal cost.
... A particularly pernicious and challenging one to address has been that of the contaminated environment. Whyte et al. (1982) and Edmiston et al. (2005) have described the general link between airborne contamination and SSIs, with an esti- mated 30-98% of wound bacteria attributable to airborne contaminants, depending on the ventilation system in an operating room. In higher income countries, invasive procedures are typically performed by scrub-attired personnel striving to reduce con- tamination in operating rooms with meticulously filtered air. ...
Book
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This open access book presents 18 case studies that explore current scientific and technological efforts to address global development issues, such as poverty, from a holistic and interdisciplinary point of view, putting actual impacts at the centre of its analysis. It illustrates the use of technologies for development in various fields of research, such as humanitarian action, medical and information and communication technology, disaster risk-reduction technologies, habitat and sustainable access to energy. The authors discuss how innovative technologies, such as unmanned aerial vehicles for disaster risk reduction, crowdsourcing humanitarian data, online education and ICT-based medical technologies can have significant social impact. The book brings together the best papers of the 2016 International Conference on Technologies for Development at EPFL, Switzerland. The book explores how the gap between innovation in the global South and actual social impact can be bridged. It fosters exchange between engineers, other scientists, practitioners and policy makers active at the interface of innovation and technology and human, social, and economic development.
... Contamination of rooms of unaffected patients is due to viability of organisms shed by previous occupants. But it could also be due to horizontal transmission from healthcare workers, visitors, or asymptomatic carriers as well as dissemination of the organisms through air flow or other means [11,12]. e incidence of hospital-associated infections due to emerging antimicrobial resistant organisms is also increasing leading to higher morbidity and mortality [13,14]. ...
Article
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Background Nosocomial infections occur among patients during their stay in hospitals. The severity of infection depends on the characteristics of microorganisms with a high risk of being acquired when the environment is contaminated. Antibiotic-resistant bacteria are emerging rapidly around the globe creating a serious threat. Methods A cross-sectional study was conducted from December 2016–February 2017 at Mizan-Tepi University Teaching Hospital, Southwest Ethiopia. Samples were collected from the equipment and hospital surfaces. The isolated bacteria were checked for susceptibility by the Kirby–Bauer disc diffusion method following the standards of CLSI 2014. Health professionals and sanitary team members were included in the study which assessed the disinfection practice of objects from which samples were taken. Data were analyzed using SPSS version 20.0. Results A total of 201 swab samples were taken, and most bacteria were recovered from thermometer and floor consisting of 21.6% S. aureus, 19.3% CoNS, 15.9% E. coli, 14.8% Klebsiella species, 11.4% P. aeruginosa, 10.2% Proteus species, and 6.8% Serratia species. The most multidrug resistant organisms were S. aureus (79%), Klebsiella species (53.8%), CoNS (47%), and Proteus species (44.4%). Only 6.45% of health professionals disinfect their stethoscope consistently. Conclusion S. aureus, CoNS, and E. coli were the predominant isolates. Most isolates showed highest susceptibility to ciprofloxacin and least to ampicillin and penicillin. There is no regular sanitation and disinfection of hospital equipment and surfaces.
Article
Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogenic S aureus strain characteristic associated with increased patient morbidity and mortality. The health care system needs to understand MRSA transmissibility in all settings to improve basic preventive measures to generate sustained reductions in invasive MRSA infections. Our primary aim was to compare intraoperative transmissibility of MRSA versus methicillin-sensitive S aureus (MSSA) isolates. Methods: S aureus isolates (N = 173) collected from 274 randomly selected operating room environments (first and second case of the day in each operating room, a case pair) at 3 hospitals underwent systematic-phenotypic and genomic processing to identify clonally related transmission events. Confirmed transmission events were defined as at least 2 S aureus isolates obtained from ≥2 distinct intraoperative reservoirs sampled within or between cases in a study unit that were epidemiologically and clonally related. We explored the relationship between clonal transmission and methicillin resistance with Poisson regression analysis. Results: We identified 58 clonal transmission events. MRSA isolates were associated with increased risk of clonal transmission compared with MSSA isolates (adjusted incidence risk ratio [IRR], 1.68; 95% confidence interval [CI], 1.13-2.49; P = .010; unadjusted IRR, 1.85; 95% CI, 1.23-2.77; P = .003, respectively). Conclusions: MRSA isolates are associated with increased risk of intraoperative transmission. Future work should examine the impact of the attenuation of intraoperative MRSA transmission on the incidence of invasive MRSA infections.
Article
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Background and Objectives: The presence of biological aerosols in the air of medical centers is more than other enclosed spaces. Determining the role and importance of such factors has always attracted the attention of health and medical researchers. This study aimed to evaluate the bacterial density of surgical and infectious wards in two important hospitals of Kermanshah and environmental factors affecting them. Methods: In this study, a total of 160 samples were selected. One hundred and twenty eight samples were related to the air of surgical and infectious wards in two stages before and after disinfection of wards and 32 samples were related to the hospital outdoor air as the control sample. MCS Flite (SKC) air sampling pump was equipped with a Biostage 225 (SKC) microbial sampling cassette made in the USA. Data were analyzed with SPSS 19. Results: The highest bacterial density in the air was measured in Imam Khomeini Hospital (402.7± 200.3 CFU/m3) and the lowest was in Imam Reza Hospital (258.6 ± 90.5 CFU/m3). There was a significant inverse relationship between air temperature and total bacterial density and a significant direct relationship between the whole population and bacterial density. Conclusion: It seems that reduced bacterial density in wards’ air with increased temperature occurs due to increasing the air volume and replacing air in wards. The presence of people in the ward plays an important role in increased bacterial density.
Chapter
Hydrocephalus should be seen as a condition rather than a disease. Since different conditions can lead to hydrocephalus, the treatment has to be adapted and tailored to each patient. Whenever possible, the cause of hydrocephalus should be directly addressed. Tumor resection and endoscopic procedures for third ventriculostomy or cyst fenestration can often prevent the insertion of cerebrospinal fluid (CSF) shunts. There is no ideal shunt so far; therefore, every effort and measures should be taken to avoid shunt insertion. It is so important to treat every hydrocephalous patient as individual case, and strategic planning should be made for a lifelong management.
Article
Background: Increased awareness of the epidemiology of transmission of pathogenic bacterial strain characteristics may help to improve compliance with intraoperative infection control measures. Our aim was to characterize the epidemiology of intraoperative transmission of high-risk Staphylococcus aureus sequence types (STs). Methods: S aureus isolates collected from 3 academic medical centers underwent whole cell genome analysis, analytical profile indexing, and biofilm absorbance. Transmission dynamics for hypertransmissible, strong biofilm-forming, antibiotic-resistant, and virulent STs were assessed. Results: S aureus ST 5 was associated with increased risk of transmission (adjusted incidence risk ratio, 6.67; 95% confidence interval [CI], 1.82-24.41; P = .0008), greater biofilm absorbance (ST 5 median absorbance ± SD, 3.08 ± 0.642 vs other ST median absorbance ± SD, 2.38 ± 1.01; corrected P = .021), multidrug resistance (odds ratio, 7.82; 95% CI, 2.19-27.95; P = .002), and infection (6/38 ST 5 vs 6/140 STs; relative risk, 3.68; 95% CI, 1.26-10.78; P = .022). Provider hands (n = 3) and patients (n = 4) were confirmed sources of ST 5 transmission. Transmission locations included provider hands (n = 3), patient skin sites (n = 4), and environmental surfaces (n = 2). All observed transmission stories involved the within-case mode of transmission. Two of the ST 5 transmission events were directly linked to infection. Conclusions: Intraoperative S aureus ST 5 isolates are hypertransmissible and pathogenic. Improved compliance with hand hygiene and patient decolonization may help to control the spread of these dangerous pathogens.
Article
Microorganisms that cause surgical site infections may either be present on the patient's skin or mucous membranes or transmitted to the patient by health care personnel, the environment, or other items in the perioperative setting. This literature review analyzes the evidence used to support the recommendation that perioperative personnel should cover their heads, hair, and ears in the semirestricted and restricted areas. A literature search produced 27 articles related to bacterial shedding from skin and hair, pathogenic organisms present on the hair and ears, and case reports of infectious organisms passed from health care providers to patients. Although there is no conclusive evidence that wearing a head covering can help prevent surgical site infections, the potential benefits to patients when compared with the risks suggest that perioperative team members should cover their heads, hair, and ears in the semirestricted and restricted areas to provide the best possible protection for surgical patients. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.
Thesis
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The history of surgery is nearly as old as the human race. Control of wound infection has always been an essential part of any surgical procedure, and is still an important challenge in hospital operating rooms today. For patients undergoing surgery there is always a risk that they will develop some kind of postoperative complication. It is widely accepted that airborne bacteria reaching a surgical site are mainly staphylococci released from the skin flora of the surgical staff in the operating room and that even a small fraction of those particles can initiate a severe infection at the surgical site. Wound infections not only impose a tremendous burden on healthcare resources but also pose a major threat to the patient. Hospital-acquired infection ranks amongst the leading causes of death within the surgical patient population. A broad knowledge and understanding of sources and transport mechanisms of infectious particles may provide valuable possibilities to control and minimize postoperative infections. This thesis contributes to finding solutions, through analysis of such mechanisms for a range of ventilation designs together with investigation of other factors that can influence spread of infection in hospitals, particularly in operating rooms. The aim of this work is to apply the techniques of computational fluid dynamics in order to provide better understanding of air distribution strategies that may contribute to infection control in operating room and ward environments of hospitals, so that levels of bacteria-carrying particles in the air can be reduced while thermal comfort and air quality are improved.
Article
Background: During the early era of arthroplasty, the concept of ultraclean operating room (OR) was introduced based on the principle that the number of airborne particles in the OR directly influences incidence of device-related infections. The hypothesis of this pilot study was that use of an innovative UV-C air decontamination technology would lead to a reduction in the incidence of periprosthetic joint infection (PJI) following total joint arthroplasty. Methods: A retrospective, observational, surveillance study was conducted with a consecutive series of patients who underwent total joint arthroplasty (n = 496) between January 2016 and August 2017. All perioperative and postoperative care protocols were identical for both groups, only study variable was that in 231 arthroplasty patients (OR B), an innovative supplemental UV-C air decontamination technology was used, whereas in the remaining 265 patients, arthroplasty was performed with standard turbulent HVAC (OR A). Results: There was no significant difference between patient groups regarding age, body mass index, diabetes diagnosis, smoking status, length of surgery, or revision status. The rate of PJI was documented to be 1.9% in the turbulent air group, and no infections were documented in the cohorts operated under UV-C air decontamination, which was statistically significant (P < .044). Conclusion: While PJI is multifactorial in nature, the present retrospective pilot study suggests that use of an intraoperative supplemental air decontamination significantly reduced the overall risk of PJI. The findings of this study are encouraging and should be examined in a larger-scale, prospective, multicenter study.
Article
Background: Operating room (OR) reservoir Staphylococcus aureus isolates have been linked to 50% of surgical site infections. We aimed to assess S aureus transmission dynamics in today's ORs to further guide health care-associated infection prevention. Methods: Forty OR case-pairs were randomly selected for observation in a 5-month prospective cohort study. Case-pair S aureus transmission dynamics were mapped using OR PathTrac. Results: S aureus pathogens were isolated from ≥1 OR reservoirs in 45.7% (37 of 81) of surgical cases, and epidemiologically related transmission events were confirmed in 22.5% (9 of 40) of case-pairs. Patient skin sites and provider hands provided comparable risk of OR S aureus exposure (19 of 481 patient vs 35 of 1,173 provider hands, relative risk [RR], 1.32; 95% confidence interval [CI], 0.77-2.29; P = .32). Environmental contamination at case 2 start was higher than at case 1 start (case 2 start 32 of 152 sites with >20 colony-forming units vs case 1 start 7 of 163 sites with >20 colony-forming units; RR, 4.90; 95% CI, 2.23-10.77; P < .0001). The stopcock contamination rate was not significantly different than our prior study in 2008 (19 of 164 2008 vs 8 of 77 2018; RR, 1.12; 95% CI, 0.51-2.43; P = .78). All epidemiologically related transmission events involved the between-case mode of transmission and phenotype H. Conclusions: Current OR S aureus exposure threats reliably include patient skin sites and provider hands. Perioperative S aureus preventive measures should extend from patient decolonization to include improved hand decontamination efforts.
Article
Background One of the important factors for surgical site infection prevention is implementation of an ultraclean operating room. This study was designed to evaluate back-table sterility during total joint arthroplasty (TJA). Methods This prospective study includes 52 patients undergoing primary TJA between November 2021 and January 2022. A total of 4 swabs (two air swabs and two table swabs) were obtained for each case, at the conclusion of surgery and prior to take down of drapes. One swab from each set was sent for culture and the other was sent for Next Generation Sequencing (NGS) analysis. Results Among 104 swabs sampling back-table, a total of 13 (12.5%) isolated organisms. Of these, 7 isolated by culture and 6 by NGS. No microorganisms isolated by both culture and NGS from back-table swabs. Among 104 swabs sampling the air, a total of 11 (10.6%) isolated organisms. Of these, 6 isolated by culture and 5 by NGS. In four of 104 swabs both culture and NGS isolated organisms from air swabs. There were 13 of 104 (12.5%) back-table and air swabs culture positive. While more than one pathogen was identified in two air swabs, all back-table swabs were monomicrobial by culture. Pathogens were identified from 11 of 104 (10.6%) swabs by NGS, more than one pathogen was identified in four swabs (2 air and 2 back-table). Discussion The findings of this study raise an important issue in that surgical field including the sterile table set-up for instruments is not “sterile” and can harbor pathogens.
Article
The onset of post-operatory surgical-site infections is significantly correlated with the concentration of viable airborne bacteria that are shed from the surgical team or entering the operating room during door openings and are deposited directly on the patient's wound or on surgical instruments. The ultra-clean vertical laminar airflow ventilation system is often used to protect the main surgical area of operating rooms. The clean zone provided by the laminar airflow system is crowded with staff and furniture. As a result, some surgical instruments might remain outside the protected area. We use a numerical simulation to investigate the capability of a portable ultra-clean airflow unit to reduce the contamination of the principal instrumentation table by airborne bacteria, during a sham operation. The numerical model is thoroughly validated against the experimental data available for a test room. The portable air-cleaning device maintains sterile conditions on the principal instrumentation table over a range of flow rates of the general ventilation, although it induces higher levels of bacterial contamination in other zones of the room at the same time.
Article
Surgeons use irrigation during open cavity procedures to improve their view of the patient's anatomy and to reduce the patient's risk of infection. However, there are no standard guidelines that recommend a specific type of fluid, additive, or volume of irrigation to use during open procedures. Intraoperative hypothermia can occur if irrigation fluids have not been warmed or have cooled before use, causing adverse patient outcomes. In addition, failing to manage (eg, measure and document) fluid volume accurately may affect clinical decision making and cause other complications. Perioperative personnel should evaluate new technologies that may improve the efficiency and accuracy of irrigation temperature and volume measurements. More research is needed to develop standardized practice guidelines for intraoperative irrigation and fluid management.
Article
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Microbial contamination of the Operating Theatre (OT) has continued to increase the prevalence of nosocomial infections. This study assessed the level of microbial contamination and the antimicrobial pattern of the bacterial isolates. Swab plate method was used to collect samples from surfaces and other articles in the major OT. Collected samples were transported and microbiologically processed using standard procedures. Three hundred and fifty (350) swab specimens were collected from various inanimate objects and surfaces in the operating theatre. Of the three hundred and fifty specimens collected, two hundred and five (205=58.6 %) swab specimens had bacterial growth. The total of 393 bacterial pathogens were recovered from all specimens processed during the study. Among these, 245(62.3 %) were Gram-positive and 148(37.7 %) were Gram-negative bacteria. The bacteria isolates were, Staphylococcus aureus 50(57.5 %), Coagulase negative Staphylococci 19(21.8 %), Bacillus species 9(10.3 %), Enterobacter species 6(3.8 %), Micrococcus species 6(6.9 %), Streptococcus species 3(4.4 %).Proteus species 128(86.5 %), E. coli 13(8.8 %), and Salmonella species 7(4.7 %). Antibiotic susceptibility pattern of bacterial pathogens showed overall sensitivity of 95 % to Rocephin. 3(100 %). Erythromycin and Gentamycin were resistant to the tested organisms. In general, the results indicate that Staphylococcus aureus, coagulase-negative Staphylococci and Proteus species were the major species contaminating the surfaces in the operating rooms. This may be due to Staphylococci been of human origin. Microbiological surveillance of operating theatres can play an important role in reducing bacterial contamination consequently preoperative infectious episodes can be reduced considerably.
Article
Injection safety is essential to reduce healthcare-associated infection (HAI) risks when accessing vascular catheters. This general review evaluates vascular catheter access port contamination and associated HAIs in acute care settings focusing on open lumen stopcocks (OLSs) and disinfectable needleless closed connectors (DNCCs). PubMed was searched from January 2000 to February 2021. OLS intraluminal surfaces are frequently contaminated during patient care, increasing HAI risks, and neither an isopropyl alcohol (IPA) pad nor a port-scrub device effectively reduces contamination. In contrast, DNCCs can be disinfected, with most studies indicating less intraluminal contamination than OLSs and some studies showing decreased HAIs. While the optimal DNCC design for reducing HAIs needs to be determined, DNCCs alone or stopcocks with a DNCC bonded to the injection port should replace routine use of OLSs, with OLSs restricted to use on sterile fields. Disinfection compliance is essential immediately before DNCC access since using a non-disinfected DNCC can be an equivalent or greater HAI risk than using an OLS. The recommendations for access port disinfection in selected national and international guidelines vary. When comparing in vitro studies, clinical studies and published guidelines a consensus is lacking, therefore additional studies are needed including large randomized controlled trials. IPA caps disinfect DNCCs passively, eliminate scrubbing and provide a contamination barrier; however, their use in neonates has been questioned. Further study is needed to determine whether IPA caps are more efficacious than scrubbing with disinfectant for decreasing HAIs related to use of central venous, peripheral venous and arterial catheters.
Article
Background: The Neptune® surgical suction system (NSSS) and the Bair Hugger® (BH) forced-air warmer both discharge filtered exhaust or heated air into the OR, often in close proximity to a surgical site. Aim: To assess the effectiveness of this filtration, we examined the quantity and identity of microbial colonies emitted from their output ports compared to those obtained from circulating air entering the OR. Methods: Air samples were collected from each device using industry standard sampling devices in which a measured volume of air is impacted onto a blood agar plate at a controlled flow rate. Twelve ORs were studied. Sample plates were incubated for one week per study protocol, then interpreted for colony counts and sent for species identification. Findings: The average colony count from the NSSS exhaust was not significantly different from that obtained from room air samples, however the average count from the BH output was significantly higher (p=0.0086) than room air. Genetic identification profiles revealed the presence of environmental or commensal organisms that differed depending on the source. High variability in colony counts from both devices suggests that certain NSSS and BH devices could be significant sources of OR air contamination. Conclusions: Our study showed that the BH patient warming device could be a source of airborne microbial contamination in the OR and that individual BH and NSSS units exhibit a higher output of microbial CFUs than would be expected compared to incoming room air. We make simple suggestions on ways to mitigate these risks.
Article
Surgical site infections (SSIs) are among the most common and most costly health care-associated infections, leading to adverse patient outcomes and death. Wound contamination occurs with each incision, but proven strategies exist to decrease the risk of SSI. In particular, improved adherence to evidence-based preventive measures related to appropriate antimicrobial prophylaxis can decrease the rate of SSI. Aggressive surgical debridement and effective antimicrobial therapy are needed to optimize the treatment of SSI.
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Background Reduced vancomycin susceptibility in Staphylococcus aureus (S. aureus) is considered a more pathogenic strain characteristic and is associated with treatment failure. We aimed to characterise the epidemiology of intraoperative transmission of S. aureus isolates with reduced vancomycin susceptibility. Methods S. aureus isolates (N=173) collected from 274 randomly selected operating room environments at three major academic medical centres in 2009-2010 were characterised by vancomycin minimum inhibitory concentration (MIC). We aimed to characterise the transmission dynamics for VISA and isolates with relatively reduced vancomycin (MIC= 2μg/mL) susceptibility at the range of therapeutic differentiation. Results Intraoperative S. aureus MIC was 1.38 ± 0.34 μg/mL. No VISA isolates were identified (95% upper confidence limit 2.1%) and those with an MIC of 2 μg/mL accounted for 12.72% (22/173) of all isolates. MIC=2 μg/mL isolates were more frequently cultured from the hands of healthcare providers [19.3% (16/83)] versus otherwise [6.7% (6/90)], with unadjusted risk ratio 2.89, p=0.021, and from patients with >2 major comorbidities [25.0% (8/32)] versus otherwise [9.9% (14/141)], with unadjusted risk ratio 2.52, P=0.035. Both were significant when tested simultaneously. The adjusted relative risk for provider hands was 2.77 (95% CI 1.15 to 6.69, P=0.024). The adjusted relative risk for patients with >2 major comorbidities was 2.37 (95% CI 1.11 to 5.05, P=0.026). MIC=2μg/mL was not associated with greater risk of clonal transmission (unadjusted P=0.34, adjusted P=0.18). Conclusion Intraoperative VISA is a rare event. S. aureus isolates MIC=2μg/mL isolates were not associated with increased risk of intraoperative transmission. The epidemiology of detected intraoperative transmission is consistent with Centers for Disease Control guidelines.
Article
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Strain typing is an integral part of epidemiological investigations of nosocomial infections. Methods for distinguishing among bacterial strains have improved dramatically over the last 5 years, due mainly to the introduction of molecular technology. Although not all molecular techniques are equally effective for typing all organisms, pulsed-field gel electrophoresis is the technique currently favored for most nosocomial pathogens. Criteria to aid epidemiologists in interpreting results have been published. Nucleic acid amplification-based typing methods also are applicable to many organisms and can be completed within a single day, but interpretive criteria still are under debate. Strain typing cannot be used to replace a sound epidemiological investigation, but serves as a useful adjunct to such investigations.
Article
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Slime-producing coagulase-negative staphylococci are pathogens in vascular surgery by virtue of their ability to adhere to and persist on prosthetic graft material. Inguinal and abdominal skin sites were cultured in 41 patients upon hospitalization, and slime production and antimicrobial susceptibility were assessed in all recovered staphylococcal isolates. Twenty-one patients eventually underwent lower-extremity revascularization. In the operative population, cultures were also obtained on the day of surgery and fifth postoperative day. All 21 patients received perioperative cefazolin. Of 327 coagulase-negative staphylococci recovered, Staphylococcus epidermidis (47%), S. haemolyticus (21%), and S. hominis (10%) were the predominant isolates. Slime-producing coagulase-negative staphylococci were recovered from 17 of 21 patients at admission but only from 8 of 21 patients on day 5 postoperation (P less than 0.05). S. epidermidis isolates demonstrated increasing multiple resistance from admission to 5 days postoperation to methicillin, gentamicin, clindamycin, erythromycin, and trimethoprim-sulfamethoxazole (P less than 0.05). All coagulase-negative staphylococcal isolates were susceptible to ciprofloxacin and vancomycin. Slime-producing capability was not associated with increased methicillin resistance for the recovered isolates. The data demonstrate that patients enter the hospital colonized with slime-producing strains of coagulase-negative staphylococci and that during hospitalization the staphylococcal skin burden shifts from a predominately susceptible to a resistant microbial population, which may enhance the importance of slime production as a risk factor in lower-extremity revascularization.
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To measure the impact of orthopedic surgical-site infections (SSIs) on quality of life, length of hospitalization, and cost. A pairwise-matched (1:1) case-control study within a cohort. A tertiary-care university medical center and a community hospital. Cases of orthopedic SSIs were prospectively identified by infection control professionals. Matched controls were selected from the entire cohort of patients undergoing orthopedic surgery who did not have an SSI. Matching variables included type of surgical procedure, National Nosocomial Infections Surveillance risk index, age, date of surgery, and surgeon. Quality of life, duration of postoperative hospital stay, frequency of hospital readmission, overall direct medical costs, and mortality rate. Fifty-nine SSIs were identified. Each orthopedic SSI accounted for a median of 1 extra day of stay during the initial hospitalization (P = .001) and a median of 14 extra days of hospitalization during the follow-up period (P = .0001). Patients with SSI required more rehospitalizations (median, 2 vs 1; P = .0001) and more total surgical procedures (median, 2 vs 1; P = .0001). The median total direct cost of hospitalizations per infected patient was $24,344, compared with $6,636 per uninfected patient (P = .0001). Mortality rates were similar for cases and controls. Quality of life was adversely affected for patients with SSI. The largest decrements in scores on the Medical Outcome Study Short Form 36 questionnaire were seen in the physical functioning and role-physical domains. Orthopedic SSIs prolong total hospital stays by a median of 2 weeks per patient, approximately double rehospitalization rates, and increase healthcare costs by more than 300%. Moreover, patients with orthopedic SSIs have substantially greater physical limitations and significant reductions in their health-related quality of life.
Article
Background : Nasal carriage of Staphylococcus aureus is common among health care workers, but outbreaks caused by such carriers are relatively uncommon. We previously reported outbreaks of S. aureus skin infections that affected newborn infants and were attributed to an S. aureus nasal carrier who had had an associated upper respiratory tract infection (URI) during the outbreak period. Objective : To investigate the contribution of a nasal methicillin-resistant S. aureus (MRSA) carrier (physician 4) who contracted a URI to an outbreak of MRSA infections that involved 8 of 43 patients in a surgical intensive care unit during a 3-week period. Design : An epidemiologic study of an outbreak of MRSA infections and a quantitative investigation of airborne dispersal of S. aureus associated with an experimentally induced rhinoviral infection. Setting : A university hospital. Participants : 43 patients in a surgical intensive care unit and 1 physician. Measurements : Molecular typing was done, and risk factors for MRSA colonization were analyzed. Agar settle plates and volumetric air cultures were used to evaluate the airborne dispersal of S. aureus by physician 4 before and after a rhinoviral infection and with or without a surgical mask. Results : A search for nasal carriers of MRSA identified a single physician (physician 4) ; molecular typing showed that the MRSA strain from physician 4 and those from the patients were identical. Multivariate logistic regression analysis identified exposure to physician 4 and duration of ventilation as independent risk factors for colonization with MRSA (P < 0.008). Air cultures showed that physician 4 dispersed little S. aureus in the absence of a URI. After experimental induction of a rhinovirus URI, physician 4's airborne dispersal of S. aureus without a surgical mask increased 40-fold ; dispersal was significantly reduced when physician 4 wore a mask (P < 0.015). Conclusions : Physician 4 became a cloud adult, analogous to the cloud babies described by Eichenwald and coworkers who shed S. aureus into the air in association with viral URIs. Airborne dispersal of S. aureus in association with a URI may be an important mechanism of transmission of S. aureus.
Article
Many organisms that are responsible for low-grade infection after total hip replacement (THR) are not recognized by routine culture. We examined wound contamination during primary total hip replacement performed in standard and ultra-clean operating theaters. 20 THRs were performed in each type of theater. Paired tissue specimens taken at the beginning and end of surgery were analyzed by bacterial culture and for the presence of bacterial DNA by the polymerase chain reaction (PCR). In total, 160 specimens (80 for culture, 80 for PCR) from 40 THRs were tested. In standard theaters, none of the 20 specimens taken at the start of surgery were positive by culture, but 3 were positive by PCR (15%). Of the 20 specimens taken at the end of surgery, 2 were positive by enriched culture and 9 were positive by PCR. All specimens positive by culture were also positive by PCR. In ultra-clean theaters, none of the 20 specimens taken at the start of surgery were positive by culture, but 2 were positive by PCR. Of the 20 specimens taken at the end of surgery, none were positive by culture, but 6 were positive by PCR. All specimens that were positive by culture were positive by PCR. Wound contamination of primary THR occurs frequently in both standard and ultra-clean operating theaters and contamination is greater at the end of surgery than at the beginning (p=0.04). In this small series, we found no differences in wound contamination between standard and ultra-clean theaters (p=0.1).
Article
• Areas of potential contamination of the surgical wound in the conventional operating rooms include the back table, the unsterile suction receptacle, and the lack of a positive pressure relationship between the operating room and adjacent areas. Use of an impermeable hood with a large mask diminished contamination of the instrument table and the wound from fallout of bacteria from the surgical team. The level of airborne bacterial contamination in the operating room can be reduced by limiting the traffic and controlling the activity and the number of operating room personnel. Higher rates of postoperative wound sepsis were noted in older operating rooms, particularly with difficult procedures and those performed later in the day. Conventional operating rooms should be categorized by the level of room air exchange per hour and the level of airborne bacterial contamination. (Arch Surg 114:772-775, 1979)
Article
The influence of airborne bacteria on wound contamination during biliary surgery was studied. When bacteria grew in the bile they accounted for most of the bacteria in the wound but when the wounds were free of bile bacteria many of the bacteria came from the patient's skin. It was only in wounds with little contamination from non-airborne routes that it was possible to demonstrate an effect of airborne contamination. In such a situation it was estimated that a reduction in the airborne bacteria in the operating room of about 13-fold would reduce the wound contamination by about 50%. The contamination of patient drapes from various sources and its relationship to wound contamination was studied. It was demonstrated that in areas away from the wound, the bacterial concentration on the drape surface was significantly affected only by airborne bacteria. In the area close to the wound, airborne bacteria and bacteria from the wound significantly affected drape contamination. However, it was found that more bacteria transferred from the wound to the drape surface than vice versa. Punctured gloves, impervious gowns and the number of bacteria on the patient's skin did not significantly affect the counts on the drapes' surfaces.
Article
A study was undertaken to determine the relative importance of some sources, routes of transmission, and measures to prevent bacteria entering the wound during biliary tract surgery. When bacteria were growing in the bile they accounted for the majority (greater than 99%) of the bacteria found in the wound. However, when the bile was sterile the skin bacteria at the incision site were found to make a substantial contribution to the wound flora. The difference in the total wound contamination between a patient who had practically no skin bacteria and one who had an average amount was in the region of 17-fold. No transfer of skin bacteria from the surgical team through perforated gloves or by direct contact from the surface of operating gowns was demonstrated. Ten of the patients studied had septic wounds. Five of these were infected by bacteria from the bile.
Article
This chapter discusses the purification, specific fragmentation, and separation of large DNA molecules. Three new techniques have been recently developed that allow the fractionation and analysis of DNA molecules on a size scale much larger than previously possible. Electrophoresis techniques developed in the past 50 years have allowed effective separation of proteins and nucleic acids on the basis of molecular weight. DNA molecules above 20 kb long usually cannot be separated by gel electrophoresis because they are larger than the pore size of the matrix. In standard gel electrophoresis, the electrical field is applied constantly in one direction. Pulse times used with PFG electrophoresis can be tuned such that maximal separation of particular sized molecules is obtained.
Article
An investigation was made into the sources of bacterial contamination of hip and knee joint replacement operations carried out in either a conventionally-ventilated or a laminar-flow operating room. It was demonstrated that the bacterial count in the air during the operations was 413/m3 in the conventionally-ventilated and 4/m3 in the laminar-flow room (a 97-fold reduction) and the average number of bacteria washed out after surgery was 105 and three, respectively (a 35-fold reduction); these facts suggest that 98 per cent of bacteria in the patients' wounds, after surgery in the conventionally-ventilated operating room, came directly or indirectly from the air. It was also ascertained that the minority of bacteria in the wound fell directly from the air (perhaps 30 per cent); the remainder presumably fell on to other surfaces and were transferred indirectly to the wound by other routes. Analysis of the relationship between the number of bacteria washed from the wound at the end of operation to both the number of bacteria in the air of the operating room and those on the patient's skin at the wound site, clearly showed that the most important and consistent route of contamination was airborne. However, on occasions when patients had exceptionally high skin carriage of bacteria, gross wound contamination occurred.
Article
Small numbers of organisms can cause orthopaedic implant infections, which give rise to a considerable degree of morbidity and also mortality. The periprosthetic infection rates have been shown to correlate with the number of airborne bacteria within 30 cm of the wound. This is influenced by factors such as the number of operating theatre personnel, their clothing and the type of ventilation system used. Guidance on routine bacteriological monitoring of ultraclean air theatres, based on the Department of Health document Health Technical Memorandum 2025, is discussed. Factors important in minimizing the number of postoperative implant infections such as the use of ultraclean air, ultraviolet radiation, different types of surgical clothing, prophylactic antibiotics and host-related factors are also discussed. The importance of proper scientific investigation into the effectiveness of practical preventative measures in the operating room is emphasized.
Article
Intraoperative sampling of airborne particulates is rarely performed in the OR environment because of technical difficulties associated with sampling methodologies and because of the common belief that airborne contamination is infrequently associated with surgical site infections (SSIs). In this study, investigators recovered non-viable (i.e., lint) and viable (i.e., microorganisms) particulates during vascular surgery using a personal cascade impactor sampling device. The predominant nonviable particulates recovered during intraoperative sampling were wood pulp fibers from disposable gowns and drapes. Several potential nosocomial pathogens (e.g., Staphylococcus aureus, Staphylococcus epidermidis) and other drug-resistant isolates frequently were recovered from an area adjacent to the surgical field. The widespread presence of airborne particulates during surgery suggests that further studies are warranted to assess the role these particles may play in the development of SSIs or in dissemination of nosocomial pathogens within the OR and hospital environment.
Article
Coagulase-negative staphylococci cause 33% to 62.5% of wound infections after cardiac operations. The aim of this study was to investigate the sources of coagulase-negative staphylococci in the sternal wound. Twenty operations performed in zonal ventilated operating rooms were investigated prospectively. Cultures were taken from all persons present in the room, the sternal wound, and the air. Isolates macroscopically judged to be coagulase-negative staphylococci were metabolically classified, and similar isolates were investigated by pulsed-field gel electrophoresis. Bacterial counts in the operating room air were very low. Wound contamination was found in 13 of 20 operations. Six wound isolates could be traced, three to the patients' sternal skin, one to the patient's groin, one to the surgeon's nose, and one to the surgeon's arm and forehead and the assistant's nose. Three operating field air cultures could be traced to the scrubbed theatre staff. The single case of superficial sternal wound infection was caused by Staphylococcus aureus, which was not isolated from the wound at operation. In an ultraclean environment, bacteria in the sternal wound originated from the patients' own skin and from the surgical team.
Article
To trace the routes of transmission and sources of Staphylococcus aureus found in the surgical wound during cardiothoracic surgery and to investigate the possibility of reducing wound contamination, with regard to total counts of bacteria and S. aureus, by wearing special scrub suits. A total of 65 elective operations for coronary artery bypass graft with or without concomitant valve replacement were investigated. All staff present in the operating room wore conventional scrub suits during 33 operations and special scrub suits during 32 operations. Bacteriological samples were taken from the hands of the scrubbed team after surgical scrub but before putting on sterile gowns and gloves and from the patients' skin (incisional area of sternum and vein harvesting area of legs) after preoperative skin preparation with chlorhexidine gluconate. Air samples were taken during operations. Bacteriological samples also were taken from the subcutaneous walls of the surgical wound just before closing the wound. Total counts of bacteria on sternal skin and wound walls (colony-forming units [CFUs]/cm2) were calculated, as well as total counts of bacteria in the air (CFUs/m3). Strains of S. aureus recovered from the different sampling sites were compared by pulsed-field gel electrophoresis (PFGE). Special scrub suits significantly reduced total counts of bacteria in air compared to conventional scrub suits (P=.002). The number of air samples in which S. aureus was found was significantly reduced by special scrub suits compared with conventional scrub suits (P=.016; relative risk, 4.4; 95% confidence interval [CI95], 1.3-14.91). By use of PFGE, it was possible to identify two cases of possible airborne transmission of S. aureus when wearing conventional scrub suits, whereas no case was found when wearing special scrub suits. When exposed to airborne S. aureus, the concomitant sternal carriage of S. aureus was a risk factor for having S. aureus in the wound. Use of tightly woven special scrub suits reduces the dispersal of total counts of bacteria and of S. aureus from staff in the operating room, thus possibly reducing the risk of airborne contamination of surgical wounds. The importance of careful preoperative disinfection of the patient's skin should be stressed.
Article
Surgical-site infection is the leading complication of surgery. Normal skin flora of patients or healthcare workers causes more than half all infections following clean surgery, but the importance of airborne bacteria in this setting remains controversial. Modern operating theatres have conventional plenum ventilation with filtered air where particles >/=5 microm are removed. For orthopaedic and other implant surgery, laminar-flow systems are used with high-efficiency particulate air (HEPA) filters where particles >/=0.3 microm are removed. The use of ultra-clean air has been shown to reduce infection rates significantly in orthopaedic implant surgery. Few countries have set bacterial threshold limits for conventionally ventilated operating rooms, although most recommend 20 air changes per hour to obtain 50-150 colony forming units/m(3) of air. There are no standardized methods for bacterial air sampling or its frequency. With the use of HEPA filters in operating theatre ventilation, there is a tendency to apply cleanroom technology standards used in industry for hospitals. These are based on measuring the presence of particles of varying sizes and numbers, and are better suited than bacterial sampling. Environmental bacterial sampling in operating theatres should be limited to investigation of epidemics, validation of protocols, or changes made in materials which could influence the microbial content.
Article
A surgical site infection (SSI) develops in 2% to 5% of patients undergoing operation. We report SSI surveillance at Baystate Medical Center, Springfield, Mass, in coronary artery bypass operation between 1991 and 2001, and demonstrate a substantial decline in SSI rates accomplished with use of multiple intervention strategies. Infection documentation used Centers for Disease Control and Prevention (CDC) criteria and a postdischarge questionnaire. Infections were stratified by risk class. Strategies used to lower SSI rates included active surveillance and provision of authenticated SSI rate plus surgeon-specific rates. Interventions included outbreak analyses and targeted nasal mupirocin plus chlorhexidine showering. The rate of coronary artery bypass-related SSIs declined from >8% to <2%, comparing extremely favorably with CDC national data. Percentage of infections documented by postdischarge questionnaire was variable and did not change during the study period. Most SSIs were at the harvest site. Routine implementation of nasal mupirocin plus chlorhexidine preoperative showering effectively disrupted an outbreak of Staphylococcus aureus, and statistically decreased rates of postoperative infections with this organism. Regular provision of authenticated and verified data, use of postdischarge questionnaires, and careful attention to adverse trends and outbreaks with appropriate actions can substantially decrease rates of infections in coronary artery bypass operation.
Article
To investigate whether rhinovirus infection leads to increased airborne dispersal of coagulase-negative staphylococci (CoNS). Prospective nonrandomized intervention trial. Wake Forest University School of Medicine, Winston-Salem, North Carolina. Twelve nasal Staphylococcus aureus-CoNS carriers among 685 students screened for S. aureus nasal carriage. 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. 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). We believe this is the first demonstration that a viral pathogen in the upper airways can increase airborne dispersal of CoNS in nasal S. aureus carriers. Gowns, gloves, and caps had a protective effect, whereas wearing a mask did not further reduce airborne spread.
Article
An investigation was performed following two methicillin-resistant Staphylococcus aureus surgical-site infections in a 946-bed French general hospital. The investigation revealed that the outbreak involved 7 patients in 2 surgical wards and that infections were probably contracted in the operating theater from a healthcare worker suffering from chronic sinusitis.
Article
To determine whether healthy adult nasal carriers of Staphylococcus aureus can disperse S. aureus into the air after rhinovirus infection. We investigated the "cloud" phenomenon among adult nasal carriers of S. aureus experimentally infected with a rhinovirus. Eleven volunteers were studied for 16 days in an airtight chamber wearing street clothes, sterile garb, or sterile garb plus surgical mask; rhinovirus inoculation occurred on day 2. Daily quantitative air, nasal, and skin cultures for S. aureus; cold symptom assessment; and nasal rhinovirus cultures were performed. Wake Forest University School of Medicine, Winston-Salem, North Carolina. Wake Forest University undergraduate or graduate students who had persistent nasal carriage of S. aureus for 4 or 8 weeks. After rhinovirus inoculation, dispersal of S. aureus into the air increased 2-fold with peak increases up to 34-fold. Independent predictors of S. aureus dispersal included the time period after rhinovirus infection and wearing street clothes (P < .05). Wearing barrier garb but not a mask decreased dispersal of S. aureus into the air (P < .05). Virus-induced dispersal of S. aureus into the air may have an important role in the transmission of S. aureus and other bacteria.
Recognition, prevention, surceillance, and management of SSI
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Martone WJ, Nichols RL. Recognition, prevention, surceillance, and management of SSI. Clin Infect Dis 2001;33:67-8.
Guidelines for prevention of surgical site infection 1999
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Prosthetic device infections in surgery In: Nichols RL, Nyhus LM, editors. Update surgical sepsis
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Edmiston CE. Prosthetic device infections in surgery. In: Nichols RL, Nyhus LM, editors. Update surgical sepsis. Philadelphia: JB Lippincott Co; 1993. p. 444-68.
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Bischoff WE, Bassetti S, Bassetti-Wyss BA, et al. Airborne dis-persal as a novel transmission route of coagulase-negative staphylococci: interaction staphylococci and rhinovirus. Infect Control Hosp Epide-miol 2004;25:504-11
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Seabrook GR, Edmiston CE. Vascular graft infections. In: Rello J, Vanes J, Kollef M, editors. Critical care infectious diseases. Boston: Kluwer Academic Publishers; 2001. p. 873-87.
How to select and interpret molecular strain typing methods for epidemiologic studies of bacterial infections: a view for healthcare epidemiologist
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Tenover FC, Arbeit RD, Goering RV. How to select and interpret molecular strain typing methods for epidemiologic studies of bacterial infections: a view for healthcare epidemiologist. Infect Control Hsp Epidemiol 1997;18:426-39.
Guidelines for prevention of surgical site infection 1999
  • Centers for Disease Control and Prevention
How to select and interpret molecular strain typing methods for epidemiologic studies of bacterial infections: a view for healthcare epidemiologist
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