Operating Theatre Air Research Articles

Presence of the neonatal Staphylococcus capitis outbreak clone (NRCS-A) in prosthetic joint infections

Staphylococcus capitis is a coagulase-negative staphylococcus that has been described primarily as causing bloodstream infections in neonatal intensive care units (NICUs), but has also recently been described in prosthetic joint infections (PJIs). The multidrug-resistant S. capitis subsp. urealyticus clone NRCS-A, comprising three sublineages, is prevalent in NICUs across the world, but its impact on other patient groups such as those suffering from PJIs or among adults planned for arthroplasty is unknown. Genome sequencing and subsequent analysis were performed on a Swedish collection of PJI isolates (n = 21), nasal commensals from patients planned to undergo arthroplasty (n = 20), NICU blood isolates (n = 9), operating theatre air isolates (n = 4), and reference strains (n = 2), in conjunction with an international strain collection (n = 248). The NRCS-A Outbreak sublineage containing the composite type V SCCmec-SCCcad/ars/cop element was present in PJIs across three Swedish hospitals. However, it was not found among nasal carrier strains, where the less virulent S. capitis subsp. capitis was most prevalent. The presence of the NRCS-A Outbreak clone in adult patients with PJIs demonstrates that dissemination occurs beyond NICUs. As this clone has several properties which facilitate invasive infections in patients with medical implants or immunosuppression, such as biofilm forming ability and multidrug resistance including heterogeneous glycopeptide-intermediate susceptibility, further research is needed to understand the reservoirs and distribution of this hospital-associated pathogen.

Does using outpatient room air for bleomycin foam preparation increase the risk of infection?

To evaluate whether the risk of infections is increased with the use of air from outpatient rooms to prepare bleomycin foam. Settling plates were adopted to collect bacteria from outpatient room air, operating theatre air, human serum albumin, bleomycin solution and bleomycin foam prepared with both outpatient room and operating theatre air. The plates were placed in an incubator at 37°C for 48 h, and the number of bacterial colonies was recorded using colony-forming units. The results were analysed by the t-test. A retrospective study was then performed to evaluate the outpatient safety of bleomycin foam. The number of colony-forming units in the bleomycin foam produced using both operating and outpatient room air was very low, with no statistic difference. No infection cases were reported in clinical evaluation. Using the air from outpatient treatment rooms for bleomycin foam preparation does not increase the risk of infections.

Effect of an exfoliating skincare regimen on the numbers of epithelial squames on the skin of operating theatre staff, studied by surface microscopy

The shedding of epithelial squames (skin scales) by staff in operating theatre air is an important source of deep infection following joint replacement surgery. This is a serious complication, resulting in significant morbidity for the patient and substantial cost implications for healthcare systems. Much effort has been put into providing clean air in operating theatres, yet little attention has been given to reducing the shedding of surface skin scales at source. To develop a novel method for calculating surface skin scale density using surface microscopy, and to use it to evaluate the effect of a skincare regimen on operating theatre staff. Surface microscopy with Z-stacked imaging was used to visualize the effect of a skincare regimen involving three stages: washing with soap; exfoliation; and application of emollient. A USB microscope was then used in a field study to take images of the skin of operating theatre staff who applied the regimen to one lower limb the night before testing. The other limb was used as a control. Two blinded assessors analysed scale density. Z-stack images from the surface microscope enabled observations of the skincare regimen. The USB microscope also provided adequate images that enabled assessment of skin scale density. In the operating theatre staff, a 72.1% reduction in visible skin scales was observed following application of the skincare regimen. Further work is required to demonstrate how this effect correlates with dispersion of skin particles in a cleanroom, and subsequently in live operating theatre studies.

Five-year microbiological monitoring of wards and operating theatres in southern Italy.

Nosocomial infections are one of the greatest problems in public health. Several studies have highlighted the role played by the hospital environment as a possible source of transmission of nosocomial pathogens. A five-year monitoring of bacterial contamination on healthcare workers hands, surfaces most closely in contact with inpatient wards, operating theatres and "at rest" and "in use" operating theatre air samples. For the samples, we used sterile swabs, contact slides, manual API, and automated VITEK systems for identification. In the five-year period, a total of 9396 samples were collected and analysed. In ward patients, 4398 samplings were carried out with 4.7%, 9.4%, 7%, 10.8% and 7.9% positive results respectively from 2010 to 2014. For hands, 648 samplings were carried out, with a positivity of 40.74%. In operating theatres, 4188 samples were taken, with a positivity of 11.9%. Regarding air in empty and full theatres, 1962 samplings were carried out with a positivity rate equal to 31.9%. The monitoring showed a low rate of contamination with a progressive decrease in the fiveyear period on operating theatres surfaces and hands, while there was an increase in the surgical site wards and in the air of operating rooms. Our investigation has revealed the presence of pathogens on the assessed surfaces and the need for environmental monitoring, which can be a valuable tool for reducing contamination.

Diathermy smoke: hazardous to health?

The heat used in electrocautery causes cells to boil and explode, or simply dry up, producing a gaseous by-product known as diathermy smoke. This smoke may have mutagenic and carcinogenic potential, similar to that of cigarette smoke ( Spearman et al, 2007 ). A search of electronic databases was performed and selected articles were reviewed using the Critical Appraisal Skills Programme (CASP) tool to enable a review of relevant material to be undertaken. The findings of the review identified 45 compounds, 9 of these were found to be hazardous when cross referenced against the Control of Substances Hazardous to Health (COSHH) list of approved workplace exposure limits ( Health and Safety Executive (HSE), 2011 ) and 4 were carcinogens. This research indicates that the use of an extraction device to remove smoke when using diathermy is best practice. However, until more conclusive evidence is available on the actual health risks of diathermy smoke, as opposed to the potential health risks, it will be difficult for organisations that govern health and safety at work to create legislation on the need to extract it from the operating theatre air.

P11.23 Effect of forced-air warming (FAW) on operating theatre air quality: assessment using computer modeling and submicron particle release

P11.23 Effect of forced-air warming (FAW) on operating theatre air quality: assessment using computer modeling and submicron particle release

P11.22 Time trend of Legionella colonization in the waterline of a hospital of Rome, Italy

P11.22 Time trend of Legionella colonization in the waterline of a hospital of Rome, Italy

Selected ion flow tube studies of the reactions of H3O+, NO+ and O2+ with the anaesthetic gases halothane, isoflurane and sevoflurane.

We have carried out a study of the reactions of H(3)O(+), NO(+) and O(2) (+), the commonly used precursor ions for selected ion flow tube mass spectrometry (SIFT-MS), with three anaesthetic gases, halothane, isoflurane and sevoflurane. The motivation for this study was to provide the necessary kinetic data that would allow the quantification of these anaesthetic gases in operating theatre air and in the breath of theatre staff and post-operative patients. A clear negative result from these experiments is that NO(+), although undergoing the simplest chemistry, is unsuitable for this SIFT-MS application. However, although the ion chemistry of H(3)O(+) and O(2) (+) with these compounds is very complex, there being several product ions in each reaction, many of which react rapidly with water molecules, monitor ions have been identified for all three anaesthetic gases when using H(3)O(+) and O(2) (+) as precursor ions. The detailed ion chemistry is discussed and the specific monitor ions are indicated. Hence, the feasibility of on-line breath monitoring is demonstrated by simple examples. These studies have opened the way to measurements in the clinical environment.

The gas chromatographic separation of anaesthetic agents and aerosol propellants in operating room air using serially packed columns

The use of gas chromatographic columns serially packed with molecular sieve 5A and Porapak-Q (both with particle sizes in the range 50–80 mesh) is described for the analysis of operating theatre air for nitrous oxide, halothane, trichloroethylene, enflurane, Freon-11 and Freon-12. Various combinations of lengths of the two packings were evaluated; the most suitable was 2.75 m of Porapak-Q and 0.29 m of molecular sieve 5A with a column temperature of 250°C. With the electron capture detector used, the optimum temperature to give high sensitivity for nitrous oxide was 350°C.

Bacterial contamination of intraocular lens surgery.

One hundred sterile intraocular lenses were placed on the external eye of 50 patients during cataract surgery. Half of the specimens were cultured for bacteria, the other half were examined under the light microscope after fixing and staining. A bacterial contamination rate of 26% was recorded. This is significantly higher than that found in conjunctival swabs (6%) or irrigation specimens (8%) taken at the same time, and higher than that recorded in a group of control lenses (15.2%) exposed to operating theatre air alone. We propose that intraocular lenses contaminated with viable bacteria may be implanted into the eye and thereby account for some cases of postoperative uveitis in the pseudophakic eye.

The bacteria stop system of Meierhans-Weber as room air technical alternative to laminar-air-flow and its air hygienic effectiveness

Statistics of wound infections demonstrate the linear dependence between postoperative wound infection and the quantity of bacteria in the air of operating theatres. In the most extensive examination series we have made as yet with a special work group of DGOT the quantity of bacteria in the air of non air-conditioned operating theatres and such fitted out with different aircleaning systems was determined. Non air-conditioned operating theatres proved so extremely infected that the risk of wound infection cannot be borne any more in the future. Also air-conditioned systems according to DIN 1946/4 with an average of 190 bacteria/m3 are not sufficiently secure for bone and joint surgery. In Switzerland for such operations a value of 10/m3 at the most is admissible. Such equivalents have been attained only with LAF until today. After extensive air tests the so-called "Keimstop"-system by Meierhans and Weber is to be considered the sole system suitable to supplement air conditioning DIN 1946/4. This combination yields the same effect as the expensive LAF systems.

Determination of halothane in operating theatre air by using a passive organic vapour dosimeter.

Determination of halothane in operating theatre air by using a passive organic vapour dosimeter.

Aspergillus prosthetic valve endocarditis.

The clinical, laboratory, and histopathological features of seven cases of Aspergillus fumigatus prosthetic valve endocarditis are presented. The exact nature of the lesion, a combination of infective fungal endocarditis and thrombosis on the prosthetic valve, is discussed and the difficulties in clinical diagnosis are emphasized. Helpful indications were sudden unexplained heart failure with the appearance of new murmurs, and emboli to large or medium-sized systemic arteries. Fever and anaemia were inconstant, and in no case was blood culture or precipitin investigation helpful. Spore contamination of operating theatre air was the likely source of infection, and measures taken to overcome this and other predisposing factors are discussed. Since medical diagnosis is usually late and the few reported cures in this condition have included replacement of the prosthesis, early surgical intervention combined with antifungal chemotherapy is advised.

AN OCCUPATIONAL HEALTH APPROACH TO ANAESTHETIC AIR POLLUTION

The principles of occupational health practice as applicable to operating theatre staff are stated. Operating theatre air was samples for halothane at three Sydney hospitals--one in which a scavenging system was in operation and two without such a system. A method giving time-weighted average concentrations over the period of sampling was used. Anaesthetic techniques varied for adults and children. The scavenging system was found to be highly efficient. Less than 0.1 ppm of halothane was found in the air of one theatre in which a flow rate of 4 litres per minute with 0.5% halothane and controlled ventilation were being used for routine anaesthetics in adults. In another theatre in which paediatric surgery was being performed, the anaesthetic technique utilized a flow rate of 6 litres per minute with 0.5% halothane and a T-piece, and the air was found to contain 0.8 ppm of halothane. Concentrations of up to 8 ppm were found in unscavenged theatres. Other possible occupational hazards of the environment, such as exposure to X-rays, viral infection and aerosol sprays, are mentioned. These may be significant.