Accumulation and transport of microbial-size particles in a pressure protected model burn unit: CFD simulations and experimental evidence.
Background: Controlling airborne contamination is of major importance in burn units because of the high susceptibility of burned patients to infections and the unique environmental conditions that can accentuate the infection risk. In particular the required elevated temperatures in the patient room...
| Publicado en: | BMC Infectious Diseases Vol. 11; no. 1; pp. 58 - 59 |
|---|---|
| Autores principales: | , , , , , , , , , , , |
| Formato: | research Journal Article |
| Publicado: |
BioMed Central
2011
|
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=104847148&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 104847148 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 14712334 1CHU jtl: BMC Infectious Diseases issn: 14712334 maglogo: N pubinfo: dt: 2011 vid: 11 iid: 1 pid: 24147 pub: BioMed Central artinfo: ui: 104847148 104847148 NLM21371304 2010980351 10.1186/1471-2334-11-58 NLM21371304 PMC3056797 104847148 ppf: 58 ppct: 1 formats: tig: atl: Accumulation and transport of microbial-size particles in a pressure protected model burn unit: CFD simulations and experimental evidence. aug: au: Beauchêne, Christian Laudinet, Nicolas Choukri, Firas Rousset, Jean-Luc Benhamadouche, Sofiane Larbre, Juliette Chaouat, Marc Benbunan, Marc Mimoun, Maurice Lajonchère, Jean-Patrick Bergeron, Vance Derouin, Francis affil: Laboratory of Parasitology-Mycology, Saint-Louis hospital, Assistance Publique-Hôpitaux de Paris, and University Paris, Diderot, France. francis.derouin@sls.aphp.fr. sug: subj: Air Microbiology Biomedical Engineering Methods Burn Units Particulate Matter Analysis Atmospheric Pressure Computer Simulation France Risk Assessment ab: Background: Controlling airborne contamination is of major importance in burn units because of the high susceptibility of burned patients to infections and the unique environmental conditions that can accentuate the infection risk. In particular the required elevated temperatures in the patient room can create thermal convection flows which can transport airborne contaminates throughout the unit. In order to estimate this risk and optimize the design of an intensive care room intended to host severely burned patients, we have relied on a computational fluid dynamic methodology (CFD).Methods: The study was carried out in 4 steps: i) patient room design, ii) CFD simulations of patient room design to model air flows throughout the patient room, adjacent anterooms and the corridor, iii) construction of a prototype room and subsequent experimental studies to characterize its performance iv) qualitative comparison of the tendencies between CFD prediction and experimental results. The Electricité De France (EDF) open-source software Code_Saturne® (http://www.code-saturne.org) was used and CFD simulations were conducted with an hexahedral mesh containing about 300 000 computational cells. The computational domain included the treatment room and two anterooms including equipment, staff and patient. Experiments with inert aerosol particles followed by time-resolved particle counting were conducted in the prototype room for comparison with the CFD observations.Results: We found that thermal convection can create contaminated zones near the ceiling of the room, which can subsequently lead to contaminate transfer in adjacent rooms. Experimental confirmation of these phenomena agreed well with CFD predictions and showed that particles greater than one micron (i.e. bacterial or fungal spore sizes) can be influenced by these thermally induced flows. When the temperature difference between rooms was 7°C, a significant contamination transfer was observed to enter into the positive pressure room when the access door was opened, while 2°C had little effect. Based on these findings the constructed burn unit was outfitted with supplemental air exhaust ducts over the doors to compensate for the thermal convective flows.Conclusions: CFD simulations proved to be a particularly useful tool for the design and optimization of a burn unit treatment room. Our results, which have been confirmed qualitatively by experimental investigation, stressed that airborne transfer of microbial size particles via thermal convection flows are able to bypass the protective overpressure in the patient room, which can represent a potential risk of cross contamination between rooms in protected environments. pubtype: Academic Journal doctype: research Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
|---|