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Journal of Hospital Infection
, Pages 59-64
Author links open overlay panelJ.G.Brock-UtneEnvelopeJ.T.WardPersonEnvelopeR.A.Jaffe
The Neptune® surgical suction system (NSSS) and the Bair Hugger® (BH) forced-air warmer both discharge filtered exhaust or heated air into the operating room (OR), often in close proximity to a surgical site.
To assess the effectiveness of this filtration, we examined the quantity and identity of microbial colonies emitted from their output ports compared with those obtained from circulating air entering the OR.
Air samples were collected from each device using industry-standard sampling devices in which a measured volume of air is impacted on to 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.
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.
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 cfu than would be expected compared with incoming room air. We make simple suggestions on ways to mitigate these risks.
Great lengths have been taken in previous decades to reduce the risk of surgical site infections (SSIs). Airborne pathogens have been recognized as a source of these infections to the extent that in the USA the Centers for Disease Control and Prevention (CDC) and Healthcare Infection Control Practices Advisory Committee (HICPAC) have made several recommendations related to the handling of operating room (OR) air which include the use of high-efficiency filtration . Our study examined whether two common devices used in the OR may inadvertently be contributing to the burden of airborne microbes and thereby potentially increasing the risk of SSI.
The Neptune® surgical suction system (NSSS) (Stryker Worldwide, Kalamazoo, MI, USA) is a self-contained portable suction system employed widely in hospitals throughout the country, and it has replaced traditional wall suction-based systems in many ORs. It is considered by some to be a less hazardous and more efficient method of handling surgical suction waste . The authors of this study have often observed multi-coloured deposits (possible microbial growth) on the inner walls of the NSSS collection canister that may persist for months despite adherence to the recommended cleaning protocols. Because fluid suctioned from a surgical site is often contaminated with antibiotics administered during surgery, these canisters have the potential to be reservoirs of antibiotic-resistant organisms which, if not properly isolated from the rest of the OR, could have important consequences for SSIs. This isolation depends entirely on the function of the confinement systems within the machine including a high-efficiency particulate air (HEPA) filter.
The Bair Hugger® (BH) forced-air warmer (3M® Company, Maplewood, MN, USA) has been a mainstay of temperature management in the OR for many years. The heated air this device produces is delivered in very close proximity to the patient and the surgical site, and because of this, it has been the subject of previous investigations as a potential source of SSIs. These studies, while not directly linking the device to infections, have shown that it can disrupt the air flow patterns employed in ORs to prevent SSIs [, , , , ]. The importance of this exhausted air being free of potential pathogens is essential, and to that end each BH contains a HEPA filter located at the air intake at the base of the machine.
The filters in use in both the NSSS and BH should, in theory, ensure that the output or exhaust from these devices is at least as clean as the filtered air entering the OR. HEPA filters are manufactured to a minimum efficiency of 99.97% for the removal of particles greater than 0.3μm, but both time and particulate loading tend to degrade that efficiency . This is why manufacturers often recommend both interval-based and usage-based replacement schedules for every filter (e.g., 12 months or 500h of use). At some large institutions including ours, the interval-based replacement schedule presents less of a logistical challenge and is used for these devices.
To test the effectiveness of this filtration at eliminating airborne microbes, we sampled the exhaust air from 12 NSSS and 11 BH devices in 12 separate ORs. This was carried out to count and identify any colony forming units (cfu) they emitted, and then these data were compared with samples from the filtered room air entering the randomly selected ORs in which these devices were in use. We assumed that the HEPA-filtered air emitted from the NSSS and the BH devices would contain lower average colony counts compared with that found at the OR fresh air inlet.
Air samples were collected from a total of 12 randomly selected ORs following the completion of an open surgical procedure approximately 5–15min after the patient and surgical team had exited but prior to OR cleaning. ORs at our institution undergo at least 12–20 air exchanges per hour in compliance with State guidelines. In each room, samples were taken from the ceiling OR air inlet, the open NSSS exhaust port at the bottom of the machine and from the open end of the BH hose. These were
Sample data are shown in TableII. Using the unpaired two-sample Kolmogorov–Smirnoff test, average colony counts (adjusted to cfu/m3) from the NSSS exhaust (13.54 cfu/m3) were not significantly different from those obtained from room air (8.75 cfu/m3; P=0.69); however, the average number of colonies from the BH hose (26.04 cfu/m3) was significantly higher compared with room air (P=0.0086). This difference persisted when outlier data from OR 14 was excluded (P=0.022). A dot plot representation
Our results confirm that air samples from the BH outlet hose contain a larger number of bacteria on average than the air coming in through the OR ceiling inlets despite regularly scheduled maintenance and the use of high-efficiency filters. The potential risk of blowing air containing bacteria-laden particles in close proximity to the patient and surgical site should not be underestimated. Although the isolates were of low virulence, we feel it is the mechanism of contamination that is the more
Support for bacteriological testing and reporting was provided by Stryker® with the direct assistance of their Senior Principal Scientist in the Instrument Division, Rod Parker, Ph.D. Dr. Parker provided the industry standard microbial air samplers and helped with the collection of the samples.
Conflict of interest statement
The authors have no conflict to declare.
Support for bacteriological testing and reporting was provided by Stryker®. All other financial support and equipment was provided solely from institutional and/or departmental sources.
- C.E. Edmiston et al.Molecular epidemiology of microbial contamination in the operating roomenvironment: Is there a risk for infection?
- M. Albrecht et al.Forced-air warming blowers: an evaluation of filtration adequacy and airborne contamination emissions in the operating room
Am J Infect Control
- L. Sehulster et al.
Guidelines for environmental infection control in health-care facilities. Recommendations of CDC and the Healthcare Infection Control Practices Advisory Committee (HICPAC)
MMWR Recomm Rep
(2003 Jun 06)
- M. Horn et al.
Traditional canister-based open waste management system versus closed system: Hazardous exposure prevention and operating theatre staff satisfaction
- P.D. McGovern et al.
Forced-air warming and ultra-clean ventilation do not mix: an investigation of theatre ventilation, patient warming and joint replacement infection in orthopaedics
J Bone Joint Surg Br.
- A.J. Legg et al.
Do forced air patient-warming devices disrupt unidirectional downward airflow?
JBone Joint Surg Br
- K.B. Dasari et al.
Effect of forced-air warming on the performance of operating theatre laminar flow ventilation
There are more references available in the full text version of this article.
Bair Hugger: A potential enemy within the operating room
2022, Infection Control and Hospital Epidemiology
Numerical assessment of ceiling-mounted air curtain on the particle distribution in surgical zone
2022, Journal of Thermal Analysis and Calorimetry
Research articleAdherence of nurses to annual seasonal influenza vaccination over a 5-year period
Journal of Hospital Infection, Volume 112, 2021, pp. 6-15
Healthcare workers (HCWs) are at risk of influenza infection with associated nosocomial transmission. Sustained adherence to seasonal influenza vaccination uptake each year is important in epidemic control.
To assess the adherence of nurses to seasonal influenza vaccination over 5 years and its associated factors.
A cross-sectional study was conducted among nurses after the winter influenza season in Hong Kong in March 2019. Based on influenza vaccine uptake rates in the 2014/15–2018/19 seasons, respondents were stratified into three groups: ‘full adherence’ (vaccine uptake in five seasons), ‘partial adherence’ (vaccine uptake in one to four seasons) and ‘non-adherence’ (no vaccine uptake). Stepwise multi-variable logistic regression was performed to determine the associations between adherence to annual influenza vaccination, respondents’ characteristics and considerations for vaccination.
Of 1306 nurses recruited, the majority were female (88%) with a median age of 36 years (interquartile range 30–46 years). The influenza vaccination uptake rate increased from 36% in the 2014/15 season to 47% in the 2018/19 season. After stratification, 39%, 40% and 21% of respondents were non-adherers, partial adherers and full adherers, respectively. Full adherence was significantly associated with female gender [adjusted odds ratio (aOR) 0.60], age ≥40 years (aOR 2.92), long-term care facility nurse (aOR 0.56), uptake during studentship (aOR 3.83), local prevalence of seasonal influenza (aOR 0.51) and expert opinion (aOR 4.04).
A limited proportion of nurses were fully adherent to seasonal influenza vaccination. Monitoring adherence, improving access to vaccines, and interventions targeting less-adherent HCWs are crucial.(Video) See How Termites Inspired a Building That Can Cool Itself | Decoder
Research articleNear-field airborne particle concentrations in young children undergoing high-flow nasal cannula therapy: a pilot study
Journal of Hospital Infection, Volume 113, 2021, pp. 14-21
High-flow nasal cannula therapy (HFNC) may increase aerosol generation, putting healthcare workers at risk, including from SARS-CoV-2.
To examine whether use of HFNC increases near-field aerosols and whether there is an association with flow rate.
Subjects aged four weeks to 24 months were recruited. Each child received HFNC therapy at different flow rates. Three stations with particle counters were deployed to measure particle concentrations and dispersion in the room: station 1 within 0.5 m, station 2 at 2 m, and station 3 on the other side of the room. Carbon dioxide (CO2) and relative humidity were measured. Far-field measurements were used to adjust the near-field measurements.
Ten children were enrolled, aged from 6 to 24 months (median: 9). Elevated CO2 indicated that the near-field measurements were in the breathing plane. Near-field breathing plane concentrations of aerosols with diameter 0.3–10 μm were elevated by the presence of the patient with no HFNC flow, relative to the room far-field, by 0.45 particles/cm3. Whereas variability between subjects in their emission and dispersion of particles was observed, no association was found between HFNC use, at any flow rate, and near-field particle counts.
This method of particle sampling is feasible in hospital settings; correcting the near-patient aerosol and CO2 levels for the room far-field may provide proxies of exposure risk to pathogens generated. In this pilot, near-patient levels of particles with a diameter between 0.3 and 10 μm and CO2 were not affected by the use of HFNC.
Research articleBarriers and enablers to implementinghospital-acquired urinary tract infection prevention strategies: a qualitative study using the Theoretical Domains Framework
Journal of Hospital Infection, Volume 113, 2021, pp. 172-179
Consistent implementation of evidence-based hospital-acquired urinary tract infection (UTI) prevention strategies remains a challenge in acute and subacute care settings. Addressing the evidence–practice gap requires an understanding of factors affecting implementation of hospital-acquired UTI prevention strategies in this high-risk setting.
To identify the perceived barriers and enablers of clinicians to implementing hospital-acquired UTI prevention strategies in an Australian subacute hospital.
Qualitative semi-structured virtual interviews, underpinned by the Theoretical Domains Framework (TDF), were conducted with purposively selected nurses (N= 8) and doctors (N= 2) at one subacute metropolitan hospital. Interview data were content-analysed using the TDF as the coding framework.
Eight TDF domains were identified as important in understanding barriers and enablers to implementing hospital-acquired UTI prevention strategies: Knowledge, Skills, Beliefs about capabilities, Emotion, Professional role and identity, Environmental context and resources, Goals, and Behavioural regulation. Barriers were poor awareness of clinical practice guidelines for hospital-acquired UTI prevention; lack of training; staff shortages; competing workloads; lack of procedural equipment for urinary catheterization; difficulty with implementing prevention strategies in cognitively impaired patients; language barriers; and lack of feedback and use of incident reporting data to influence clinical practice. Presence of a proactive staff culture and positive team approach to work emerged as enablers. Audit and feedback, clinical champions, education, and patient information resources in languages other than English were identified as potential enablers.
The findings will inform development of theoretically informed behaviour change interventions to promote successful implementation of hospital-acquired UTI prevention strategies in the subacute setting.
Research articleFactors associated with independent nurse prescribers' antibiotic prescribing practice: a mixed-methods study using the Reasoned Action Approach
Journal of Hospital Infection, Volume 113, 2021, pp. 22-29(Video) Cristiano Ronaldo HATES Coca-Cola
The number of nurse prescribers is increasing, yet little evidence exists about their antibiotic prescribing behaviour.
To measure nurse independent prescribers' (NIPs) intention to manage patients, presenting with an upper respiratory tract infection (URTI) for the first time, without prescribing an antibiotic and to examine the determinants of this behaviour.
This was a mixed-method study using the Reasoned Action Approach (RAA). Content analysis of data from 27 telephone interviews with NIPs informed the development of a questionnaire which was tested for validity and reliability and used in a national survey of NIPs across Scotland. Descriptive and inferential statistical analysis was carried out to determine intention to manage patients without prescribing an antibiotic and the significant influences on this intention.
From 184 participants it was found that NIPs intended to manage patients, presenting with a URTI for the first time, without prescribing an antibiotic. Key determinants were perceived norm, perceived behavioural control, and moral norm. Significant beliefs were positive social influence from other non-medical prescribers (P= 0.007) and nurse prescribers (P= 0.045), the enablers of prescriber experience and confidence (P ≤ 0.001), and the barrier of pressure from patients/carers (P= 0.010).
The findings provide reassurance that NIPs intend to prescribe appropriately. The identification of nurse-specific barriers and enablers to this intention should be acknowledged and targeted in future interventions to manage this behaviour.
Research articleExtensively-drug-resistant Klebsiella pneumoniae ST307 outbreak strain from north-eastern Germany does not show increased tolerance to quaternary ammonium compounds and chlorhexidine
Journal of Hospital Infection, Volume 113, 2021, pp. 52-58
An outbreak of extensively-drug-resistant Klebsiella pneumoniae strain ST307 in a cluster of hospitals in north-east Germany gave rise to the assumption that the epidemiological success of the strain could be based on increased tolerance to biocides.
The tolerance of the outbreak strain was compared with epidemiologically unrelated clinical isolates of K.pneumoniae, and reference strains of Pseudomonas aeruginosa (ATCC 15442) and Escherichia coli K12 (NCTC 10538). Tests were performed in a miniaturized assay based on European Standard EN 1040. The widely used biocides benzalkonium chloride (BAC) and didecyl dimethyl ammonium chloride (DDAC), their commercial formulation Descosept spezial (DS), and the antiseptic agent chlorhexidine digluconate (CHG) were selected as test substances. These biocides are used regularly in the hospitals involved in the outbreak.
All biocides had a bactericidal effect against all tested strains in the quantitative suspension test within 5 min at typically used concentrations and dilutions. The effectiveness of BAC and DDAC alone and in combination, and CHG antisepsis were not impaired under tested conditions.
The outbreak strain did not show significantly increased tolerance towards biocides regarding the antiseptic. Thus, the epidemiological success of the strain has to be ascribed to other causes, such as inadequate hand hygiene of visitors.
Research articleDeterminants of antibiotic over-prescribing for upper respiratory tract infections in an emergency department with good primary care access: a quantitative analysis
Journal of Hospital Infection, Volume 113, 2021, pp. 71-76
Upper respiratory tract infections (URTI) account for the highest proportion of non-urgent visits to the emergency department (ED), resulting in unnecessary antibiotic use.
This study sought to understand the determinants of antibiotic prescribing for URTI among 130 junior physicians in a busy adult ED in Singapore.
Forty-four Likert-scale statements were developed with reference to a prior qualitative study, followed by an anonymous cross-sectional survey among ED junior physicians. Data analysis was performed with factor reduction and multivariable logistic regression.
One-in-six (16.9%) physicians were high antibiotic prescribers (self-reported antibiotic prescribing rate of >30% of URTI patients). After adjusting for place of medical education and years of practice as a physician, perceived over-prescribing of antibiotics in the ED (adjusted odds ratio (OR) 2.37, 95% confidence interval (CI) (1.15, 4.86), P=0.019) and perceived compliance with the antibiotic prescribing practices in the ED (adjusted OR 2.10, 95% CI (1.02, 4.30), P=0.043) were positively associated with high antibiotic prescribing. In contrast, high antibiotic prescribers were 6.67 times (95% CI (1.67, 25.0), P=0.007) less likely to treat and manage patients with URTI symptomatically and 7.12 times (95% CI (1.28, 39.66), P=0.025) more likely to depend on diagnostic tests to prescribe antibiotics than the regular antibiotic prescribers.
Organizational-related factors (organizational norms and culture) were strong determinants of antibiotic prescribing practices for uncomplicated URTI in the ED. Other contributing factors include diagnostic uncertainty and knowledge gaps. Role-modelling of institutional best practice norms and clinical decision support tools based on local epidemiology can optimize antibiotic prescribing in the ED.
© 2021 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
It has been suggested that the main sources of contamination, especially in clean surgical procedures, are the patient's skin and airborne particles from operating room personnel [2, 3].
Different Types of Operating Rooms: Hybrid, Integrated, Digital O.R. - Brainlab.
Surgical site infections may be caused by endogenous or exogenous microorganisms. Most SSIs are caused by endogenous microorganisms present on the patient's skin when the surgical incision is made. Gram-positive bacteria such as Staphylococcus aureus are the most common causative skin-dwelling microorganisms.
Non-woven fabric, widely used for surgical drapes, gowns, and hoods, is thought to be one of the major origins of airborne particles in the operating room.
The surgeon is your primary doctor and considered the leader in the operating room. It is the responsibility of the surgeon to ensure the operation goes smoothly, with minimal complications.
Level 4. • Highly invasive procedure. • Blood loss greater than 1,500 cc. • Major risk to patient independent of anesthesia. Includes: Major orthopedic-spinal reconstruction, major reconstruction of the.
In the United States, an air temperature of 70 to 75°F. (21 to 24°C.) with 50 to 60% relative humidity provides a compromise between the requirements of the patients and those of the operators. In Britain, a temperature of 65 to 70°F.