Reduction of Airborne Contamination through Operating Room Apparel

AbstractBackground and Objective:Despite the novelties in operating room ventilation, airborne bacteria remain an important source of surgical wound contamination. An ultraclean airflow from the ceiling downward may convey airborne particles from the surgical team into the wound, thus increasing the risk of infection. Therefore, similar ventilation from the wound upward should be considered. We investigated the effect of wound ventilation on the concentration of airborne particles in a wound model during simulated surgery.Design:Randomized experimental study simulating surgery with a wound cavity model.Setting:An operating room of a university hospital ventilated with ultraclean air directed downward.Interventions:Particles 5 um and larger were counted with and without a 5-cm deep cavity and with and with-out the insufflation of ultraclean air.Results:With the surgeon standing upright, no airborne particles could be detected in the wound model. In contrast, during simulated operations, the median number of particles per 0.1 cu ft reached 18 (25th and 75th percentiles, 12 and 22.25) in the model with a cavity and 15.5 (25th and 75th percentiles, 14 and 21.5) without. With a cavity, wound ventilation markedly reduced the median number of particles to 1 (range, 0 to 1.25;P< .001).Conclusions:To protect a surgical wound against direct airborne contamination, air should be directed away from the wound rather than toward it. This study provides supportive evidence to earlier studies that operating room ventilation with ultraclean air is imperfect during surgical activity and that wound ventilation may be a simple complement. Further clinical trials are needed.

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Forced-air warming: a source of airborne contamination in the operating room?

Orthopedic Reviews ◽

10.4081/or.2009.e28 ◽

2009 ◽

Vol 1 (1) ◽

pp. 28 ◽

Cited By ~ 16

Author(s):

David Leaper ◽

Mark Albrecht ◽

Robert Gauthier

Keyword(s):

Operating Room ◽

Size Range ◽

Filtration Efficiency ◽

Microbial Colonization ◽

Particle Size Range ◽

Forced Air Warming ◽

Airborne Contamination ◽

Steep Decrease ◽

Forced Air ◽

Bacteria And Fungi

Forced-air-warming (FAW) is an effective and widely used means for maintaining surgical normothermia, but FAW also has the potential to generate and mobilize airborne contamination in the operating room. We measured the emission of viable and non-viable forms of airborne contamination from an arbitrary selection of FAW blowers (n=25) in the operating room. A laser particle counter measured particulate concentrations of the air near the intake filter and in the distal hose airstream. Filtration efficiency was calculated as the reduction in particulate concentration in the distal hose airstream relative to that of the intake. Microbial colonization of the FAW blower’s internal hose surfaces was assessed by culturing the microorganisms recovered through swabbing (n=17) and rinsing (n=9) techniques. Particle counting revealed that 24% of FAW blowers were emitting significant levels of internally generated airborne contamination in the 0.5 to 5.0 mm size range, evidenced by a steep decrease in FAW blower filtration efficiency for particles 0.5 to 5.0 mm in size. The particle size-range-specific reduction in efficiency could not be explained by the filtration properties of the intake filter. Instead, the reduction was found to be caused by size-range-specific particle generation within the FAW blowers. Microorganisms were detected on the internal air path surfaces of 94% of FAW blowers. The design of FAW blowers was found to be questionable for preventing the build-up of internal contamination and the emission of airborne contamination into the operating room. Although we did not evaluate the link between FAW and surgical site infection rates, a significant percentage of FAW blowers with positive microbial cultures were emitting internally generated airborne contamination within the size range of free floating bacteria and fungi (<4 mm) that could, conceivably, settle onto the surgical site.

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An evaluation of a partial-walled laminar-flow operating room

Journal of Hygiene ◽

10.1017/s0022172400023858 ◽

1974 ◽

Vol 73 (1) ◽

pp. 61-74 ◽

Cited By ~ 11

Author(s):

W. Whyte ◽

B. H. Shaw ◽

M. A. R. Freeman

Keyword(s):

Laminar Flow ◽

Operating Room ◽

Bacterial Count ◽

Air Velocity ◽

Wound Site ◽

Freedom Of Movement ◽

Sound Levels ◽

Airborne Contamination ◽

Clean Area ◽

Average Figure

SUMMARYThis paper contains an assessment of the physical performance of a permanently installed down-flow laminar-flow operating room at the London Hospital. This system employs partial walls extending 0.76 m (2.5 ft.) from the ceiling, from which the air is allowed to issue freely downwards at an initial velocity of about 0.4 m./sec. (80 ft./min.).The usefulness of the partial wall, as compared with a free issuing system, was demonstrated and a comparison made with a fully walled system. It was shown that a fully walled system would be more efficient than a partial-walled system as there was a loss in air velocity of about 20–25% with the partial wall due to the nonconstrained flow of air. This loss would be reflected in an increase in airborne bacterial count and would mean that an increase of 20–25% in the air volume would be required to obtain the same conditions as with the full-walled system. Entrainment of contaminated air was demonstrated but it was concluded that this would be of little consequence in the centre of the clean area, i.e. at the wound site. Sterile instruments, etc., however, on the outside of the clean area, would be more liable to airborne contamination.Bacterial and dust airborne counts taken during total hip operations gave a very low average figure (0.3 bacteria/ft.3 or 10.5/m.3) from which we conclude that the system was about 30 times cleaner in terms of airborne bacteria than a well ventilated conventional operating-room. We concluded that although the partial-walled system was slightly less efficacious than a normal full-walled system, the freedom of movement and of communication for the operating team could in some circumstances outweigh this disadvantage.Sound levels were such that normal conversation was possible with little or no awareness of background noise.

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A Systems Approach to Assess Transport and Diffusion of Hazardous Airborne Particles in a Large Surgical Suite: Potential Impacts on Viral Airborne Transmission

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17155404 ◽

2020 ◽

Vol 17 (15) ◽

pp. 5404 ◽

Cited By ~ 1

Author(s):

Marc Garbey ◽

Guillaume Joerger ◽

Shannon Furr

Keyword(s):

Operating Room ◽

Systems Approach ◽

Airborne Particles ◽

Mathematical Framework ◽

Airborne Transmission ◽

Surgical Smoke ◽

Airborne Contamination ◽

Transport And Diffusion ◽

And Diffusion

Airborne transmission of viruses, such as the coronavirus 2 (SARS-CoV-2), in hospital systems are under debate: it has been shown that transmission of SARS-CoV-2 virus goes beyond droplet dynamics that is limited to 1 to 2 m, but it is unclear if the airborne viral load is significant enough to ensure transmission of the disease. Surgical smoke can act as a carrier for tissue particles, viruses, and bacteria. To quantify airborne transmission from a physical point of view, we consider surgical smoke produced by thermal destruction of tissue during the use of electrosurgical instruments as a marker of airborne particle diffusion-transportation. Surgical smoke plumes are also known to be dangerous for human health, especially to surgical staff who receive long-term exposure over the years. There are limited quantified metrics reported on long-term effects of surgical smoke on staff’s health. The purpose of this paper is to provide a mathematical framework and experimental protocol to assess the transport and diffusion of hazardous airborne particles in every large operating room suite. Measurements from a network of air quality sensors gathered during a clinical study provide validation for the main part of the model. Overall, the model estimates staff exposure to airborne contamination from surgical smoke and biological material. To address the clinical implication over a long period of time, the systems approach is built upon previous work on multi-scale modeling of surgical flow in a large operating room suite and takes into account human behavior factors.

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Forced-air warming blowers: An evaluation of filtration adequacy and airborne contamination emissions in the operating room

American Journal of Infection Control ◽

10.1016/j.ajic.2010.06.011 ◽

2011 ◽

Vol 39 (4) ◽

pp. 321-328 ◽

Cited By ~ 27

Author(s):

Mark Albrecht ◽

Robert L. Gauthier ◽

Kumar Belani ◽

Mark Litchy ◽

David Leaper

Keyword(s):

Operating Room ◽

Forced Air Warming ◽

Airborne Contamination ◽

Forced Air

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Ultraviolet radiation and the control of airborne contamination in the operating room

Journal of Hospital Infection ◽

10.1016/0195-6701(94)90088-4 ◽

1994 ◽

Vol 28 (4) ◽

pp. 245-248 ◽

Cited By ~ 35

Author(s):

O.M. Lidwell

Keyword(s):

Ultraviolet Radiation ◽

Operating Room ◽

Airborne Contamination

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A Systems Approach to Assess Transport and Diffusion of Hazardous Airborne Particles in a Large Surgical Suite: Potential Impacts on Viral Airborne Transmission

10.1101/2020.05.11.20097725 ◽

2020 ◽

Author(s):

Marc Garbey ◽

Guillaume Joerger ◽

Shannon Furr

Keyword(s):

Operating Room ◽

Systems Approach ◽

Airborne Particles ◽

Mathematical Framework ◽

Airborne Transmission ◽

Surgical Smoke ◽

Airborne Contamination ◽

Transport And Diffusion ◽

And Diffusion

Airborne transmission of viruses, such as the coronavirus 2 (SARS-CoV-2), in hospital systems are under debate: it has been shown that transmission of SARS-CoV-2 virus goes beyond droplet dynamics that is limited to 3-6 feet, but it is unclear if the airborne viral load is significant enough to ensure transmission of the disease. Surgical smoke can act as a carrier for tissue particles, viruses, and bacteria. To quantify airborne transmission from a physical point of view, we consider surgical smoke produced by thermal destruction of tissue during the use of electrosurgical instruments as a marker of airborne particle diffusion-transportation. Surgical smoke plumes are also known to be dangerous for human health, especially to surgical staff who receive long-term exposure over the years. There are limited quantified metrics reported on long-term effects of surgical smoke on staff's health. The purpose of this paper is to provide a mathematical framework and experimental protocol to assess the transport and diffusion of hazardous airborne particles in every large operating room suite. Measurements from a network of air quality sensors gathered during a clinical study provide validation for the main part of the model. Overall, the model estimates staff exposure to airborne contamination from surgical smoke and biological material. To address the clinical implication over a long period of time, the systems approach is built upon previous work on multi-scale modeling of surgical flow in a large operating room suite and takes into account human behavior factors.

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Decreasing Airborne Contamination Levels in High-Risk Hospital Areas Using a Novel Mobile Air-Treatment Unit

Infection Control and Hospital Epidemiology ◽

10.1086/520733 ◽

2007 ◽

Vol 28 (10) ◽

pp. 1181-1186 ◽

Cited By ~ 21

Author(s):

V. Bergeron ◽

G. Reboux ◽

J. L. Poirot ◽

N. Laudinet

Keyword(s):

High Risk ◽

Operating Room ◽

High Efficiency ◽

Nonthermal Plasma ◽

Fungal Species ◽

Airborne Particles ◽

Treatment Unit ◽

Air Treatment ◽

Hospital Environments ◽

Airborne Contamination

Objective.To evaluate the performance of a new mobile air-treatment unit that uses nonthermal-plasma reactors for lowering the airborne bioburden in critical hospital environments and reducing the risk of nosocomial infection due to opportunistic airborne pathogens, such asAspergillus fumigatus.Methods.Tests were conducted in 2 different high-risk hospital areas: an operating room under simulated conditions and rooms hosting patients in a pediatric hematology ward. Operating room testing provided performance evaluations of removal rates for airborne contamination (ie, particles larger than 0.5μm) and overall lowering of the airborne bioburden (ie, colony-forming units of total mesophilic flora and fungal flora per cubic meter of air). In the hematology service, opportunistic and nonpathogenic airborne fungal levels in a patient's room equipped with an air-treatment unit were compared to those in a control room.Results.In an operating room with a volume of 118 m3, the time required to lower the concentration of airborne particles larger than 0.5μm by 90% was decreased from 12 minutes with the existing high-efficiency particulate air filtration system to less than 2 minutes with the units tested, with a 2-log decrease in the steady-state levels of such particles (P<.01). Concurrently, total airborne mesophilic flora concentrations dropped by a factor of 2, and the concentrations of fungal species were reduced to undetectable levels (P<.01). The 12-day test period in the hematology ward revealed a significant reduction in airborne fungus levels (P<.01), with average reductions of 75% for opportunistic species and 82% for nonpathogenic species.Conclusion.Our data indicate that the mobile, nonthermal-plasma air treatment unit tested in this study can rapidly reduce the levels of airborne particles and significantly lower the airborne bioburden in high-risk hospital environments.

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