The epidemiology of Staphylococcus aureus transmission in the anesthesia work area

Factors associated with patient-to-healthcare personnel (HCP) and HCP-to-subsequent patient transmission of methicillin-resistant Staphylococcus aureus

BACKGROUND

Transient acquisition of methicillin-resistant Staphylococcus aureus (MRSA) on healthcare personnel (HCP) gloves and gowns following patient care has been examined. However, the potential for transmission to the subsequent patient has not been studied. We explored the frequency of MRSA transmission from patient to HCP, and then in separate encounters from contaminated HCP gloves and gowns to a subsequent simulated patient as well as the factors associated with these 2 transmission pathways.

METHODS

We conducted a prospective cohort study with 2 parts. In objective 1, we studied MRSA transmission from random MRSA-positive patients to HCP gloves and gowns after specific routine patient care activities. In objective 2, we simulated subsequent transmission from random HCP gloves and gowns without hand hygiene to the next patient using a manikin proxy.

RESULTS

For the first objective, among 98 MRSA-positive patients with 333 randomly selected individual patient-HCP interactions, HCP gloves or gowns were contaminated in 54 interactions (16.2%). In a multivariable analysis, performing endotracheal tube care had the greatest odds of glove or gown contamination (OR, 4.06; 95% CI, 1.3-12.6 relative to physical examination). For the second objective, after 147 simulated HCP-patient interactions, the subsequent transmission of MRSA to the manikin proxy occurred 15 times (10.2%).

CONCLUSION

After caring for a patient with MRSA, contamination of HCP gloves and gown and transmission to subsequent patients following HCP-patient interactions occurs frequently if contact precautions are not used. Proper infection control practices, including the use of gloves and gown, can prevent this potential subsequent transmission.

Epidemiology of Enterococcus , Staphylococcus aureus , Klebsiella , Acinetobacter , Pseudomonas , and Enterobacter Species Transmission in the Pediatric Anesthesia Work Area Environment With and Without Practitioner Use of a Personalized Body-Worn Alcohol Dispenser

BACKGROUND

Personalized body-worn alcohol dispensers may serve as an important tool for perioperative infection control, but the impact of these devices on the epidemiology of transmission of high-risk Enterococcus , Staphylococcus aureus , Klebsiella, Acinetobacter , Pseudomonas , and Enterobacter (ESKAPE) pathogens is unknown. We aimed to characterize the epidemiology of ESKAPE transmission in the pediatric anesthesia work area environment with and without a personalized body-worn alcohol dispenser.

METHODS

This controlled before and after study included 40 pediatric patients enrolled over a 1-year study period. Two groups of operating room cases were compared: (1) operating room cases caring for patients with usual care (December 17, 2019, to August 25, 2020), and (2) operating room cases caring for patients with usual care plus the addition of a personalized, body-worn alcohol hand rub dispenser (September 30, 2020, to December 16, 2020). Operating rooms were randomly selected for observation of ESKAPE transmission in both groups. Device use was tracked via wireless technology and recorded in hourly hand decontamination events.

RESULTS

Anesthesia providers used the alcohol dispenser 3.3 ± 2.1 times per hour. A total of 57 ESKAPE transmission events (29 treatment and 28 control) were identified. The personalized body-worn alcohol dispenser impacted ESKAPE transmission by increasing the contribution of provider hand contamination at case start (21/29 device versus 10/28 usual care; relative risk, [RR] 2.03; 99.17% confidence interval [CI], 1.025-5.27; P = .0066) and decreasing the contribution of environmental contamination at case end (3/29 device versus 12/28 usual care; RR, 0.24; 99.17% CI, 0.022-0.947; P = .0059). ESKAPE pathogen contamination involved 20% (8/40) of patient intravascular devices. There were 85% (34/40) of preoperative patient skin surfaces contaminated with ≥1 (1.78 ± 0.19 [standard deviation {SD}]) ESKAPE pathogens.

CONCLUSIONS

A personalized body-worn alcohol dispenser can impact the epidemiology of ESKAPE transmission in the pediatric anesthesia work area environment. Improved preoperative patient decolonization and vascular care are indicated to address ESKAPE pathogens among pediatric anesthesia work area reservoirs.

Effectiveness and feasibility of an evidence-based intraoperative infection control program targeting improved basic measures: a post-implementation prospective case-cohort study

STUDY OBJECTIVE

A randomized controlled study demonstrated that an optimized intraoperative infection control program targeting basic preventive measures can reduce Staphylococcus aureus transmission and surgical site infections. In this study we address potential limitations of operating room heterogeneity of infections and compliance with behavioral interventions following adoption into clinical practice.

DESIGN

A post-implementation prospective case-cohort study.

SETTING

Twenty-three operating rooms at a large teaching hospital.

PATIENTS

A total of 801 surgical patients [425 (53%) women; 350 (44%) ASA > 2, age 54.6 ± 15.9 years] were analyzed for the primary and 804 for the secondary outcomes.

INTERVENTIONS

A multifaceted, evidence-based intraoperative infection control program involving hand hygiene, vascular care, and environmental cleaning improvements was implemented for 23 operating room environments. Bacterial transmission monitoring was used to provide monthly feedback for intervention optimization.

MEASUREMENTS

S. aureus transmission (primary) and surgical site infection (secondary).

MATERIALS AND METHODS

The incidence of S. aureus transmission and surgical site infection before (3.5 months) and after (4.5 months) infection control optimization was assessed. Optimization was defined by a sustained reduction in anesthesia work area bacterial reservoir isolate counts. Poisson regression with robust error variances was used to estimate the incidence risk ratio (IRR) of intraoperative S. aureus transmission and surgical site infection for the independent variable of optimization.

MAIN RESULTS

Optimization was associated with decreased S. aureus transmission [24% before (85/357) to 9% after (42/444), IRR 0.39, 95% CI 0.28 to 0.56, P < .001] and surgical site infections [8% before (29/360) and 3% after (15/444) (IRR 0.42, 95% CI 0.23 to 0.77, P = .005; adjusted for American Society of Anesthesiologists' physical status, aIRR 0.45, 95% CI 0.25 to 0.82, P = .009].

CONCLUSION

An optimized intraoperative infection control program targeting improvements in basic preventive measures is an effective and feasible approach for reducing S. aureus transmission and surgical site infection development.

Outbreak of Sepsis Following Surgery: Utilizing 16S RNA Sequencing To Detect the Source of Infection

Background

Nosocomial infections are a significant health concern. Following surgery, infections are most commonly associated with the surgical site, yet there are other potential sources for infections after surgical interventions. Identification of the source of infections can be very challenging.

Methodology

An outbreak of postoperative infections following surgery led to intensive care unit (ICU) admission of patients immediately after the surgical procedure. The blood cultures of two patients were positive for Citrobacter freundii. The only connection between all cases was the anesthesiologist. An epidemiological inquiry could not definitively identify the source of the outbreak. Therefore, we utilized an RNA sequencing technique to evaluate the microbiome of the anesthesiologist and compared the results to bacteria cultured from the bloodstream of the two patients.

Results

The anesthesiologist’s microbiome contained amplicons that were identical to those of the bacteria in the patient’s bloodstream. Because Citrobacter freundii is an uncommon source of bloodstream infections, and in the normal human microbiome, the results establish the source of a cluster of infections to the anesthesiologist.

Conclusions

In cases of nosocomial infections, when conventional microbiological techniques do not clearly establish the source of the infection, using 16S RNA sequencing should be considered.

Microbial contamination of the hands of healthcare providers in the operating theatre of a central hospital

Background

Effort is invested in maintaining the sterility of the operating field, but less attention is paid to potential healthcare associated infection (HAI) sources through patient contact with non-scrubbed healthcare providers (HCPs). A single microbiological assessment of hands can provide a good assessment of the potential dynamic transmission of microorganisms. The aim of this study was to identify and quantify the microbial growth on the hands of HCPs in the operating theatres of Chris Hani Baragwanath Academic Hospital.

Methods

A prospective, contextual and descriptive study design was followed. Seventy-five samples were collected using convenience sampling from an equal number of surgeons, anaesthetists and nurses. Specimens were taken using agar plates and underwent semi-quantitative analysis.

Results

All the hands of the HCPs displayed growth; 95% grew commensals and 64% grew pathogens. Eighteen commensal microorganisms and 21 pathological microorganisms were noted. Comparisons of commensal, pathological and combined levels of contamination among the three groups were not statistically significant (p = 0.061, p = 0.481, p = 0.236). No significant difference between the growth of combined microorganisms (p = 0.634) and pathological microorganisms (p = 0.499) among the groups. Surgeons had significantly more commensal growth (p = 0.041). There was no statistically significant difference between sexes (p = 0.290).

Conclusion

It was concerning that 100% of the hands of HCPs who were about to commence with the surgical list had microbial growth. These HCPs could have already been in contact with patients and equipment in the theatre environment.

Moving towards green anaesthesia: Are patient safety and environmentally friendly practices compatible? A focus on single-use devices

OBJECTIVE

Discuss if the use of disposable or reusable medical devices leads to a difference in terms of hospital-acquired infection or bacterial contamination. Determine which solution is less expensive and has less environmental impact in terms of carbon footprint, energy and water consumption and amount of waste.

METHODS

We carried out a narrative review. Articles published in English and French from January 2000 to April 2020 were identified from PubMed.

RESULTS

We retrieved 81 articles, including 12 randomised controlled trial, 21 literature reviews, 13 descriptive studies, 6 experimental studies, 9 life-cycle studies, 6 cohort studies, 2 meta-analysis, 4 case reports and 8 other studies. It appears that pathogen transmission in the anaesthesia work area is mainly due to the lack of hand hygiene among the anaesthesia team. The benefit of single-use devices on infectious risk is based on weak scientific arguments, while reusable devices have benefits in terms of costs, water consumption, energy consumption, waste, and reducing greenhouse gas emissions.

CONCLUSION

Disposable medical devices and attire in the operating theatre do not mitigate the infectious risk to the patients but have a greater environmental, financial and social impact than the reusable ones. This study is the first step towards recommendations for more environmental-friendly practices in the operating theatre.

Strategies for daily operating room management of ambulatory surgery centers following resolution of the acute phase of the COVID-19 pandemic

We performed a narrative review to explore the economics of daily operating room management decisions for ambulatory surgery centers following resolution of the acute phase of the Coronavirus Disease 2019 (COVID-19) pandemic. It is anticipated that there will be a substantive fraction of patients who will be contagious, but asymptomatic at the time of surgery. Use multimodal perioperative infection control practices (e.g., including patient decontamination) and monitor performance (e.g., S. aureus transmission from patient to the environment). The consequence of COVID-19 is that such processes are more important than ever to follow because infection affects not only patients but the surgery center staff and surgeons. Dedicate most operating rooms to procedures that are not airway aerosol producing and can be performed without general anesthesia. Increase throughput by performing nerve blocks before patients enter the operating rooms. Bypass the phase I post-anesthesia care unit whenever possible by appropriate choices of anesthetic approach and drugs. Plan long-duration workdays (e.g., 12-h). For cases where the surgical procedure does not cause aerosol production, but general anesthesia will be used, have initial (phase I) post-anesthesia recovery in the operating room where the surgery was done. Use anesthetic practices that achieve fast initial recovery of the brief ambulatory cases. When the surgical procedure causes aerosol production (e.g., bronchoscopy), conduct phase I recovery in the operating room and use multimodal environmental decontamination after each case. Use statistical methods to plan for the resulting long turnover times. Whenever possible, have the anesthesia and nursing teams stagger cases in more than one room so that they are doing one surgical case while the other room is being cleaned. In conclusion, this review shows that while COVID-19 is prevalent, it will markedly affect daily ambulatory workflow for patients undergoing general anesthesia, with potentially substantial economic impact for some surgical specialties.

Perioperative Infection Transmission: the Role of the Anesthesia Provider in Infection Control and Healthcare-Associated Infections

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.

Perioperative COVID-19 Defense: An Evidence-Based Approach for Optimization of Infection Control and Operating Room Management

We describe an evidence-based approach for optimization of infection control and operating room management during the Coronavirus Disease 2019 (COVID-19) pandemic. Confirmed modes of viral transmission are primarily, but not exclusively, contact with contaminated environmental surfaces and aerosolization. Evidence-based improvement strategies for attenuation of residual environmental contamination involve a combination of deep cleaning with surface disinfectants and ultraviolet light (UV-C). (1) Place alcohol-based hand rubs on the intravenous (IV) pole to the left of the provider. Double glove during induction. (2) Place a wire basket lined with a zip closure plastic bag on the IV pole to the right of the provider. Place all contaminated instruments in the bag (eg, laryngoscope blades and handles) and close. Designate and maintain clean and dirty areas. After induction of anesthesia, wipe down all equipment and surfaces with disinfection wipes that contain a quaternary ammonium compound and alcohol. Use a top-down cleaning sequence adequate to reduce bioburden. Treat operating rooms using UV-C. (3) Decolonize patients using preprocedural chlorhexidine wipes, 2 doses of nasal povidone-iodine within 1 hour of incision, and chlorhexidine mouth rinse. (4) Create a closed lumen IV system and use hub disinfection. (5) Provide data feedback by surveillance of Enterococcus, Staphylococcusaureus, Klebsiella, Acinetobacter, Pseudomonas, and Enterobacter spp. (ESKAPE)transmission. (6) To reduce the use of surgical masks and to reduce potential COVID-19 exposure, use relatively long (eg, 12hours) staff shifts. If there are 8 essential cases to be done (each lasting 1–2 hours), the ideal solution is to have 2 teams complete the 8 cases, not 8 first case starts. (7) Do 1 case in each operating room daily, with terminal cleaning after each case including UV-C or equivalent. (8) Do not have patients go into a large, pooled phase I postanesthesia care unit because of the risk of contaminating facility at large along with many staff. Instead, have most patients recover in the room where they had surgery as is done routinely in Japan. These 8 programmatic recommendations stand on a substantial body of empirical evidence characterizing the epidemiology of perioperative transmission and infection development made possible by support from the Anesthesia Patient Safety Foundation (APSF).

Assessment of anesthesia machine redesign on cleaning of the anesthesia machine using surface disinfection wipes

BACKGROUND

The use of surface disinfection wipes after induction of anesthesia improves anesthesia machine cleaning. We assessed whether anesthesia machine surface redesign improves disinfection wipe cleaning by anesthesia residents.

METHODS

Sixteen anesthesia residents were assigned to 2 cases in series. The first case was randomly assigned to regional knee or hip surgery, a brief or detailed checklist, and the Perseus A500 (redesigned) or GE Aespire 7900 (conventional) machine. The second case was assigned to the opposite for each condition. Setup checklists included cleaning instructions. Eight machine sites representing redesign were contaminated with fluorescent gel prior to setup and reassessed after setup to assess cleaning efficacy. Cleaning was compared by fluorescence quantification of before and after setup images. Our primary hypothesis was that, overall, more sites would be cleaned on the Perseus machine. Our secondary hypothesis was that redesign would affect some sites.

RESULTS

Overall, the number of sites cleaned did not differ between machines (median 0.74 more sites out of 8 for the Perseus A500; 25th and 75th percentiles, -0.34 and 1.04; P = .093). However, greater cleaning was observed for the work surface and manual bag arm/hose of the Perseus machine (0.58 more sites out of 2; 25th and 75th percentiles, 0.35 and 1.05; P = .0004).

CONCLUSIONS

The number of sites cleaned overall did not differ between the conventional and redesigned Perseus A500 machines. However, the redesigned work surface and smooth manual bag arm features improved resident cleaning with surface disinfection wipes.

Importance of operating room case scheduling on analyses of observed reductions in surgical site infections from the purchase and installation of capital equipment in operating rooms

BACKGROUND

We review the impact of the consequences of operating room (OR) management decision making on power analyses for observational studies of surgical site infections (SSIs) among patients receiving care in ORs with interventions versus without interventions involving physical changes to ORs. Examples include ventilation systems, bactericidal lighting, and physical alterations to ORs.

METHODS

We performed a narrative review of operating room management and surgical site infection articles. We used 10-years of operating room data to estimate parameters for use in statistical power analyses.

RESULTS

Creating pivot tables or monthly control charts of SSI per case by OR and comparing among ORs with or without intervention is not recommended. This approach has low power to detect a difference in SSI rates among the ORs with or without the intervention. The reason is that appropriate OR case scheduling decision making causes risk factors for SSI to differ among ORs, even when stratifying by surgical specialty. Such risk factors include case duration, urgency, and American Society of Anesthesiologists' Physical Status. Instead, analyze SSI controlling for the OR, where the patient had surgery, and matching patients using these variables is preferable. With α = 0.05, 600 cases per OR, 5 intervention ORs, and 5 or 1 control patients for each intervention patient, reasonable power (≅94% or 78%, respectively) can be achieved to detect reductions (3.6% to 2.4%) in the incidence of SSI between ORs with or without the intervention.

CONCLUSIONS

By using this matched cohort design, the effect of the purchase and installation of capital equipment in ORs on SSI can be evaluated meaningfully.

The Effect of Improving Basic Preventive Measures in the Perioperative Arena on Staphylococcus aureus Transmission and Surgical Site Infections: A Randomized Clinical Trial

Importance

Surgical site infections increase patient morbidity and health care costs. The Centers for Disease Control and Prevention emphasize improved basic preventive measures to reduce bacterial transmission and infections among patients undergoing surgery.

Objective

To assess whether improved basic preventive measures can reduce perioperative Staphylococcus aureus transmission and surgical site infections.

Design, Setting, and Participants

This randomized clinical trial was conducted from September 20, 2018, to September 20, 2019, among 19 surgeons and their 236 associated patients at a major academic medical center with a 60-day follow-up period. Participants were a random sample of adult patients undergoing orthopedic total joint, orthopedic spine, oncologic gynecological, thoracic, general, colorectal, open vascular, plastic, or open urological surgery requiring general or regional anesthesia. Surgeons and their associated patients were randomized 1:1 via a random number generator to treatment group or to usual care. Observers were masked to patient groupings during assessment of outcome measures.

Interventions

Sustained improvements in perioperative hand hygiene, vascular care, environmental cleaning, and patient decolonization efforts.

Main Outcomes and Measures

Perioperative S aureus transmission assessed by the number of isolates transmitted and the incidence of transmission among patient care units (primary) and the incidence of surgical site infections (secondary).

Results

Of 236 patients (156 [66.1%] women; mean [SD] age, 57 [15] years), 106 (44.9%) and 130 (55.1%) were allocated to the treatment and control groups, respectively, received the intended treatment, and were analyzed for the primary outcome. Compared with the control group, the treatment group had a reduced mean (SD) number of transmitted perioperative S aureus isolates (1.25 [2.11] vs 0.47 [1.13]; P = .002). Treatment reduced the incidence of S aureus transmission (incidence risk ratio; 0.56; 95% CI, 0.37-0.86; P = .008; with robust variance clustering by surgeon: 95% CI, 0.42-0.76; P < .001). Overall, 11 patients (4.7%) experienced surgical site infections, 10 (7.7%) in the control group and 1 (0.9%) in the treatment group. Transmission was associated with an increased risk of surgical site infection (8 of 73 patients [11.0%] with transmission vs 3 of 163 [1.8%] without; risk ratio, 5.95; 95% CI, 1.62-21.86; P = .007). Treatment reduced the risk of surgical site infection (hazard ratio, 0.12; 95% CI, 0.02-0.92; P = .04; with clustering by surgeon: 95% CI, 0.03-0.51; P = .004).

Conclusions and Relevance

Improved basic preventive measures in the perioperative arena can reduce S aureus transmission and surgical site infections.

Trial Registration

ClinicalTrials.gov Identifier: NCT03638947.

Operating room PathTrac analysis of current intraoperative Staphylococcus aureus transmission dynamics

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.

Anesthesia Workspace Cleanliness and Safety: Implementation of a Novel Syringe Bracket Using 3D Printing Techniques

Purpose

Wide variability persists in the preparation and storage of common anesthetic medications despite the recognition of anesthesia workspace standardization as a national quality improvement priority. Syringe contamination and medication swaps continue to pose significant hazards to patient safety.

Methods

We assessed differences in practice related to the availability of commonly prepared anesthetic medications. Using baseline provider surveys (n = 87) and anesthesia workspace audits (n = 80), we designed a custom syringe organization device using 3D printing techniques to serve as a cognitive aid and organizational tool. We iteratively tested and then deployed this device in all 60 operating rooms at a single institution, and then, repeated postintervention surveys (n = 79) and workspace audits (n = 75) one year after introduction.

Results

Implementation was associated with significant improvements in provider-reported medication availability during coverage and handoff situations (43.7% versus 76.2% reporting 95% confidence preintervention versus postintervention, p < 0.001). This was substantiated by audits of the anesthesia workspace which demonstrated reduced variability in the location (p < 0.001) and availability (p < 0.001) of key medications. Provider confidence in the cleanliness of syringes was also improved (p=0.01). A high degree of acceptance and compliance with the intervention was reported, with 80.4% of syringes observed to be stored in the device one year after implementation and approximately 95% of respondents reporting positive measures of usability and convenience.

Conclusion

Use of a simple organizational device for syringes in the anesthesia workspace has numerous safety benefits. 3D printing offers improvements in adaptability and affordability compared with prior approaches.

Efficacy and Usability of a Novel Barrier Device for Preventing Injection Port Contamination: A Pilot Simulation Study

Contamination of intravenous (IV) ports and stopcocks has been associated with postoperative infections. We tested the usability and efficacy of a novel passive shielding device to prevent such contamination even in the absence of hand hygiene or port disinfection. In a desktop setting with deliberately contaminated hands, qualitative port contamination was detected after 5/60 (8.3%; 95% confidence interval [CI], 2.8-18.4) control port injections versus 0/60 (0%; 95% CI, 0-6.0) shielded injections (P = .025). In clinical simulations with a quantitative bioburden assay (measured in relative light units [RLUs]), median (interquartile range [IQR]) postsimulation bioburden was 46 (32-53) vs 27 (21-42) RLU for the control versus intervention groups (P = .036), yielding a median shift of -13 RLU (95% CI, -2 to -26) in favor of the shielding. Usability of the device was acceptable to practitioners.

[Hygiene aspects of multidrug-resistant pathogens in the operating room and intensive care unit]

The major multidrug-resistant pathogens (MRE) in human medicine are methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and multidrug-resistant Gram-negative rod bacteria (MRGN). MRE are a very heterogeneous group with respect to epidemiology and therapeutic or hospital hygiene consequences. After MRSA played an important role among MREs at the beginning of the twenty-first century, VRE and MRGN have come to the fore in recent years. During work in the operating room and on the intensive care unit, there are many possibilities for transmission of MRE between the patient environment and the patient, especially via the hands, e. g. during intubation or catheterization in vessels, tissues or the urinary tract. For this reason, hand and surface hygiene is of particular relevance in the prevention of nosocomial colonization or infection, in particular with MRE.

Transmission pathways of multidrug-resistant organisms in the hospital setting: a scoping review

BACKGROUND

Prevalence of multidrug-resistant microorganisms (MDROs) continues to increase, while infection control gaps in healthcare settings facilitate their transmission between patients. In this setting, 5 distinct yet interlinked pathways are responsible for transmission. The complete transmission process is still not well understood. Designing and conducting a single research study capable of investigating all 5 complex and multifaceted pathways of hospital transmission would be costly and logistically burdensome. Therefore, this scoping review aims to synthesize the highest-quality published literature describing each of the 5 individual potential transmission pathways of MDROs in the healthcare setting and their overall contribution to patient-to-patient transmission.

METHODS

In 3 databases, we performed 2 separate systematic searches for original research published during the last decade. The first search focused on MDRO transmission via the HCW or the environment to identify publications studying 5 specific transmission pathways: (1) patient to HCW, (2) patient to environment, (3) HCW to patient, (4) environment to patient, and (5) environment to HCW. The second search focused on overall patient-to-patient transmission regardless of the transmission pathway. Both searches were limited to transmission of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus, multidrug-resistant A. baumannii, and carbapenem-resistant Enterobacteriaceae. After abstract screening of 5,026 manuscripts, researchers independently reviewed and rated the remaining papers using objective predefined criteria to identify the highest quality and most influential manuscripts.

RESULTS

High-quality manuscripts were identified for all 5 routes of transmission. Findings from these studies were consistent for all pathways; however, results describing the routes from the environment/HCW to a noncolonized patient were more limited and variable. Additionally, most research focused on MRSA, instead of other MDROs. The second search yielded 10 manuscripts (8 cohort studies) that demonstrated the overall contribution of patient-to-patient transmission in hospitals regardless of the transmission route. For MRSA, the reported cross-transmission was as high as 40%.

CONCLUSIONS

This scoping review brings together evidence supporting all 5 possible transmission pathways and illustrates the complex nature of patient-to-patient transmission of MDROs in hospitals. Our findings also confirm that transmission of MDROs in hospitals occurs frequently, suggesting that ongoing efforts are necessary to strengthen infection prevention and control to prevent the spread of MDROs.

High-risk Staphylococcus aureus transmission in the operating room: A call for widespread improvements in perioperative hand hygiene and patient decolonization practices

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.

Desiccation tolerance is associated with Staphylococcus aureus hypertransmissibility, resistance and infection development in the operating room

BACKGROUND

Desiccation tolerance increases Staphylococcus aureus survival and risk of transmission. A better understanding of factors driving intraoperative transmission of S. aureus pathogens may lead to innovative improvements in intraoperative infection control.

AIMS

To determine whether desiccation tolerance is associated with intraoperative S. aureus transmission, and to examine typical transmission dynamics for desiccation-tolerant isolates in the operating room in order to provide the impetus for development of improved intraoperative infection control strategies.

METHODS

S. aureus isolates (N=173) were collected from anaesthesia work area reservoirs in 274 operating room environments. Desiccation tolerance was assessed and the potential association with sequence type (ST) and clonal transmission was evaluated. Whole cell genome analysis and pulsed-field gel electrophoresis analysis were used to compare desiccation-tolerant isolates with causative organisms of infection.

FINDINGS

S. aureus ST 5 isolates had greater desiccation tolerance than all other intraoperative STs [ST 5, N=34, median Day 2 colony-forming unit (cfu) survival 0.027% ± 0.029%; other STs, N=139, median Day 2 cfu survival 0.0091% ± 1.41%; corrected P=0.0001]. ST 5 was associated with increased risk of clonal transmission (relative risk 1.82, 95% confidence interval 1.23-2.71, P=0.003). ST 5 transmission was linked by whole cell genome analysis to postoperative infection.

CONCLUSIONS

Increased desiccation tolerance is associated with intraoperative transmission of S. aureus ST 5 isolates that are linked to postoperative infection. Future work should determine whether attenuation of desiccation-tolerant, intraoperative ST 5 strains can impact the incidence of healthcare-associated infections.

Methicillin-resistant Staphylococcus aureus has greater risk of transmission in the operating room than methicillin-sensitive S aureus

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.

Dynamics of intraoperative Klebsiella, Acinetobacter, Pseudomonas, and Enterobacter transmission

BACKGROUND

Our primary objective was to examine anesthesia work area reservoir isolation of Klebsiella, Acinetobacter, Pseudomonas, and Enterobacter spp (KAPE) pathogens. This is a retrospective analysis of a randomized, prospective, and observational study involving 3 academic medical centers.

METHODS

Patients included adults undergoing general anesthesia. Gram-negative isolates (N = 2,682) were collected from anesthesia work area reservoirs in 274 randomly selected operating room case pairs. Nine hundred and forty-five isolates were included in this study. Chi square tests were used to examine the association of anesthesia work area reservoirs with KAPE genera isolation.

RESULTS

Acinetobacter pathogens were more likely to be isolated from anesthesia provider hands (risk ratio [RR], 1.07; 95% confidence interval [CI], 1.04-1.10; corrected P = .004) and less likely to be isolated from patients (RR, 0.2; 95% CI, 0.08-0.50; corrected P < .0001). Enterobacter pathogens were more likely to be isolated from patients (RR, 3.34; 95% CI, 1.92-5.81; corrected P = 0.001) and less likely to be isolated from provider hands (RR, 0.89; 95% CI, 0.83-0.97; corrected P = .007).

CONCLUSIONS

Anesthesia provider hands are important reservoirs for Acinetobacter spp, whereas patient skin surfaces are key reservoirs for Enterobacter spp. Future work should examine the impact of a multimodal program in controlling the intraoperative spread of Acinetobacter and Enterobacter pathogens.

Anesthesia in patients with infectious disease caused by multi-drug resistant bacteria

PURPOSE OF REVIEW

Up to 50% of specific bacterial strains in healthcare admission facilities are multi-drug resistant organisms (MDROs). Involvement of anesthesiologists in management of patients carrying/at risk of carrying MDROs may decrease transmission in the Operating Room (OR).

RECENT FINDINGS

Anesthesiologists, their work area and tools have all been implicated in MDRO outbreaks. Causes include contamination of external ventilation circuits and noncontribution of filters to prevention, inappropriate decontamination procedures for nondisposable equipment (e.g. laryngoscopes, bronchoscopes and stethoscopes) and the anesthesia workplace (e.g. external surfaces of cart and anesthesia machine, telephones and computer keyboards) during OR cleaning and lack of training in sterile drug management.

SUMMARY

Discussions regarding the management of potential MDRO carriers must include anesthesia providers to optimize infection control interventions as well as the anesthesia method, the location of surgery and recovery and the details of patient transport. Anesthesia staff must learn to identify patients at risk for MDRO infection. Antibiotic prophylaxis, although not evidence based, should adhere to known best practices. Adjuvant therapies (e.g. intranasal Mupirocin and bathing with antiseptics) should be considered. Addition of nonmanual OR cleaning methods such as ultraviolet irradiation or gaseous decontamination is encouraged. Anesthesiologists must undergo formal training in sterile drug preparation and administration.

Hand hygiene compliance monitoring in anaesthetics: Feasibility and validity

Background:

Hand hygiene compliance scores in the anaesthetic department of an acute NHS hospital were persistently low.

Aims:

To determine the feasibility and validity of regular accurate measurement of HHC in anaesthetics and understand the context of care delivery, barriers and opportunities to improve compliance.

Methods:

The hand hygiene compliance of one anaesthetist was observed and noted by a senior infection control practitioner (ICP). This was compared to the World Health Organization five moments of hand hygiene and the organisation hand hygiene tool.

Findings:

In one sequence of 55 min, there were approximately 58 hand hygiene opportunities. The hand hygiene compliance rate was 16%. The frequency and speed of actions in certain periods of care delivery made compliance measurement difficult and potentially unreliable. During several activities, taking time to apply alcohol gel or wash hands would have put the patients at significant risk.

Discussion:

We concluded that hand hygiene compliance monitoring by direct observation was invalid and unreliable in this specialty. It is important that hand hygiene compliance is optimal in anaesthetics particularly before patient contact. Interventions which reduce environmental and patient contamination, such as cleaning the patient and environment, could ensure anaesthetists encounter fewer micro-organisms in this specialty.

Assessing a Novel Method to Reduce Anesthesia Machine Contamination: A Prospective, Observational Trial

Background

Anesthesia machines are known reservoirs of bacterial species, potentially contributing to healthcare associated infections (HAIs). An inexpensive, disposable, nonpermeable, transparent anesthesia machine wrap (AMW) may reduce microbial contamination of the anesthesia machine. This study quantified the density and diversity of bacterial species found on anesthesia machines after terminal cleaning and between cases during actual anesthesia care to assess the impact of the AMW. We hypothesized reduced bioburden with the use of the AMW.

Methods

In a prospective, experimental research design, the AMW was used in 11 surgical cases (intervention group) and not used in 11 control surgical cases. Cases were consecutively assigned to general surgical operating rooms. Seven frequently touched and difficult to disinfect “hot spots” were cultured on each machine preceding and following each case. The density and diversity of cultured colony forming units (CFUs) between the covered and uncovered machines were compared using Wilcoxon signed-rank test and Student's t-tests.

Results

There was a statistically significant reduction in CFU density and diversity when the AMW was employed.

Conclusion

The protective effect of the AMW during regular anesthetic care provides a reliable and low-cost method to minimize the transmission of pathogens across patients and potentially reduces HAIs.

Design and Preliminary Testing of Novel Injection Port Contamination Barrier Devices

Prior studies have linked microbial contamination of intravenous (IV) ports and stopcocks with postoperative infections. Existing technologies to address contamination are not consistently utilized because of the time and effort they require. Herein, novel barrier devices were created that form a protective shell to passively prevent contact between injection sites and practitioner hands or environmental surfaces while still allowing rapid connection of a syringe for injection of medications via an opening in the shell. Prototypes were tested using a grossly contaminated environment and adenosine triphosphate (ATP)-bioluminescence assay. For eight pairs of unshielded versus shielded IV ports/stopcocks, average contamination was 4102 versus 35 RLU (p < 0.02), respectively, indicating that the devices could significantly reduce IV port/stopcock contamination.

Incidence of central venous catheter hub contamination

PURPOSE

To investigate microorganisms causing central venous catheter contamination and how this contamination differs across different catheter metrics.

MATERIALS AND METHODS

After obtaining IRB approval and informed consent, 830 cultures were prospectively obtained from 45 ICU patients with central venous catheter or peripherally inserted central catheter. Bacterial colonies were identified by mass spectrometry.

RESULTS

Bacterial contamination of central catheter hubs occurred 44% of the time in this study in the ICU setting. Coagulase-positive staphylococci cultures had higher median (±interquartile range) CFUs (12±232) versus coagulase-negative (3±10) and other bacteria (1±3; P<0.001). Bacterial contamination was associated with various metrics. Higher incidence (P<0.05) of coagulase-positive staphylococci cultures was associated with hub-only connections (a "hub" being a female connection; 10.9% vs. 7.9% male connections), connections without a manifold (1lumen device that mixes multiple infusions together; 9.7% vs. 0% with manifold); and central venous pressure monitoring connections (25.8% vs. 7.1% without). Internal jugular sites (10.0% vs. 2.7% femoral, 6.2% PICC, P=0.031) and medial lumens of triple lumen catheters (11.9% vs. 5.6% distal, 7.0% proximal, P=0.049) had increased incidence of higher bacteria loads (>15 CFUs).

CONCLUSIONS

This study found a high incidence of central access catheter hub bacterial contamination, which correlated with positive blood cultures in 2 of 3 total bacteremia cases identified in the 45 patients.

Fighting MRSA Infections in Hospital Care: How Organizational Factors Matter

OBJECTIVE

To identify factors associated with methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections at the level of the hospital organization.

DATA SOURCES

Data from all 173 acute trusts in the English National Health Service (NHS).

STUDY DESIGN

A longitudinal study based on trust-level panel data for the 5-year period from April 2004 to March 2009. Fixed effects negative binominal and system generalized method of moment models were used to examine the effect of (i) patient mix characteristics, (ii) resource endowments, and (iii) infection control practices on yearly MRSA counts.

DATA COLLECTION

Archival and staff survey data from multiple sources, including Public Health England, the English Department of Health, and the Healthcare Commission, were merged to form a balanced panel dataset.

PRINCIPAL FINDINGS

MRSA infections decrease with increases in general cleaning (-3.52 MRSA incidents per 1 standard deviation increase; 95 percent confidence interval: -6.61 to -0.44), infection control training (-3.29; -5.22 to -1.36), hand hygiene (-2.72; -4.76 to -0.68), and error reporting climate (-2.06; -4.09 to -0.04).

CONCLUSIONS

Intensified general cleaning, improved hand hygiene, additional infection control training, and a climate conducive to error reporting emerged as the factors most closely associated with trust-level reductions in MRSA infections over time.

Microbiological Contamination of Drugs during Their Administration for Anesthesia in the Operating Room

Background

The aseptic techniques of anesthesiologists in the preparation and administration of injected medications have not been extensively investigated, but emerging data demonstrate that inadvertent lapses in aseptic technique may be an important contributor to surgical site and other postoperative infections.

Methods

A prospective, open, microbiological audit of 303 cases in which anesthesiologists were asked to inject all bolus drugs, except propofol and antibiotics, through a 0.2-µm filter was performed. The authors cultured microorganisms, if present, from the 0.2-µm filter unit and from the residual contents of the syringes used for drawing up or administering drugs. Participating anesthesiologists rated ease of use of the filters after each case.

Results

Twenty-three anesthesiologists each anesthetized up to 25 adult patients. The authors isolated microorganisms from filter units in 19 (6.3%) of 300 cases (3 cases were excluded), including Staphylococcus capitis, Staphylococcus warneri, Staphylococcus epidermidis, Staphylococcus haemolyticus, Micrococcus luteus/lylae, Corynebacterium, and Bacillus species. The authors collected used syringes at the end of each case and grew microorganisms from residual drug in 55 of these 2,318 (2.4%) syringes including all the aforementioned microorganisms and also Kocuria kristinae, Staphylococcus aureus, and Staphylococcus hominus. Participants’ average rating of ease of use of the filter units was 3.5 out of 10 (0 being very easy and 10 being very difficult).

Conclusions

Microorganisms with the potential to cause infection are being injected (presumably inadvertently) into some patients during the administration of intravenous drugs by bolus during anesthesia. The relevance of this finding to postoperative infections warrants further investigation.

A New Approach to Pathogen Containment in the Operating Room: Sheathing the Laryngoscope After Intubation

BACKGROUND

Anesthesiologists may contribute to postoperative infections by means of the transmission of blood and pathogens to the patient and the environment in the operating room (OR). Our primary aims were to determine whether contamination of the IV hub, the anesthesia work area, and the patient could be reduced after induction of anesthesia by removing the risk associated with contaminants on the laryngoscope handle and blade. Therefore, we conducted a study in a simulated OR where some of the participants sheathed the laryngoscope handle and blade in a glove immediately after it was used to perform an endotracheal intubation.

METHODS

Forty-five anesthesiology residents (postgraduate year 2-4) were enrolled in a study consisting of identical simulation sessions. On entry to the simulated OR, the residents were asked to perform an anesthetic, including induction and endotracheal intubation timed to approximately 6 minutes. Of the 45 simulation sessions, 15 were with a control group conducted with the intubating resident wearing single gloves, 15 with the intubating resident using double gloves with the outer pair removed and discarded after verified intubation, and 15 wearing double gloves and sheathing the laryngoscope in one of the outer gloves after intubation. Before the start of the scenario, the lips and inside of the mouth of the mannequin were coated with a fluorescent marking gel. After each of the 45 simulations, an observer examined the OR using an ultraviolet light to determine the presence of fluorescence on 25 sites: 7 on the patient and 18 in the anesthesia environment.

RESULTS

Of the 7 sites on the patient, ultraviolet light detected contamination on an average of 5.7 (95% confidence interval, 4.4-7.2) sites under the single-glove condition, 2.1 (1.5-3.1) sites with double gloves, and 0.4 (0.2-1.0) sites with double gloves with sheathing. All 3 conditions were significantly different from one another at P < 0.001. Of the 18 environmental sites, ultraviolet light detected fluorescence on an average of 13.2 (95% confidence interval, 11.3-15.6) sites under the single-glove condition, 3.5 (2.6-4.7) with double gloves, and 0.5 (0.2-1.0) with double gloves with sheathing. Again, all 3 conditions were significantly different from one another at P < 0.001.

CONCLUSIONS

The results of this study suggest that when an anesthesiologist in a simulated OR sheaths the laryngoscope immediately after endotracheal intubation, contamination of the IV hub, patient, and intraoperative environment is significantly reduced.

Hand hygiene knowledge and perceptions among anesthesia providers

BACKGROUND

Health care worker compliance with hand hygiene guidelines is an important measure for health care-associated infection prevention, yet overall compliance across all health care arenas remains low. A correct answer to 4 of 4 structured questions pertaining to indications for hand decontamination (according to types of contact) has been associated with improved health care provider hand hygiene compliance when compared to those health care providers answering incorrectly for 1 or more questions. A better understanding of knowledge deficits among anesthesia providers may lead to hand hygiene improvement strategies. In this study, our primary aims were to characterize and identify predictors for hand hygiene knowledge deficits among anesthesia providers.

METHODS

We modified this previously tested survey instrument to measure anesthesia provider hand hygiene knowledge regarding the 5 moments of hand hygiene across national and multicenter groups. Complete knowledge was defined by correct answers to 5 questions addressing the 5 moments for hand hygiene and received a score of 1. Incomplete knowledge was defined by an incorrect answer to 1 or more of the 5 questions and received a score of 0. We used a multilevel random-effects XTMELOGIT logistic model clustering at the respondent and geographic location for insufficient knowledge and forward/backward stepwise logistic regression analysis to identify predictors for incomplete knowledge.

RESULTS

The survey response rates were 55.8% and 18.2% for the multicenter and national survey study groups, respectively. One or more knowledge deficits occurred with 81.6% of survey respondents, with the mean number of correct answers 2.89 (95% confidence interval, 2.78- 2.99). Failure of providers to recognize prior contact with the environment and prior contact with the patient as hand hygiene opportunities contributed to the low mean. Several cognitive factors were associated with a reduced risk of incomplete knowledge including providers responding positively to washing their hands after contact with the environment (odds ratio [OR] 0.23, 0.14-0.37, P < 0.001), disinfecting their environment during patient care (OR 0.54, 0.35-0.82, P = 0.004), believing that they can influence their colleagues (OR 0.43, 0.27-0.68, P < 0.001), and intending to adhere to guidelines (OR 0.56, 0.36-0.86, P = 0.008). These covariates were associated with an area under receiver operator characteristics curve of 0.79 (95% confidence interval, 0.74-0.83).

CONCLUSIONS

Anesthesia provider knowledge deficits around to hand hygiene guidelines occur frequently and are often due to failure to recognize opportunities for hand hygiene after prior contact with contaminated patient and environmental reservoirs. Intraoperative hand hygiene improvement programs should address these knowledge deficits. Predictors for incomplete knowledge as identified in this study should be validated in future studies.