RESUMEN
AIM: To evaluate three types of ventilation systems for operating rooms with respect to air cleanliness [in colony-forming units (cfu/m3)], energy consumption and comfort of working environment (noise and draught) as reported by surgical team members. METHODS: Two commonly used ventilation systems, vertical laminar airflow (LAF) and turbulent mixed airflow (TMA), were compared with a newly developed ventilation technique, temperature-controlled airflow (TcAF). The cfu concentrations were measured at three locations in an operating room during 45 orthopaedic procedures: close to the wound (<40cm), at the instrument table and peripherally in the room. The operating team evaluated the comfort of the working environment by answering a questionnaire. FINDINGS: LAF and TcAF, but not TMA, resulted in less than 10cfu/m3 at all measurement locations in the room during surgery. Median values of cfu/m3 close to the wound (250 samples) were 0 for LAF, 1 for TcAF and 10 for TMA. Peripherally in the room, the cfu concentrations were lowest for TcAF. The cfu concentrations did not scale proportionally with airflow rates. Compared with LAF, the power consumption of TcAF was 28% lower and there was significantly less disturbance from noise and draught. CONCLUSION: TcAF and LAF remove bacteria more efficiently from the air than TMA, especially close to the wound and at the instrument table. Like LAF, the new TcAF ventilation system maintained very low levels of cfu in the air, but TcAF used substantially less energy and provided a more comfortable working environment than LAF. This enables energy savings with preserved air quality.
Asunto(s)
Ambiente Controlado , Quirófanos , Temperatura , Ventilación/métodos , Microbiología del Aire , Contaminación del Aire Interior , Recuento de Colonia Microbiana , Humanos , Satisfacción Personal , Encuestas y CuestionariosAsunto(s)
Haptenos/análisis , Técnicas Microbiológicas , Marcadores de Afinidad , Unión Competitiva , Concanavalina A/análisis , Digoxina/análisis , Técnicas para Inmunoenzimas , Ligandos , Sustancias Macromoleculares , Saccharomyces cerevisiae/análisis , Albúmina Sérica/análisis , Staphylococcus aureus/análisis , Streptococcus agalactiae/análisis , Triyodotironina/análisisAsunto(s)
Lectinas/farmacología , Streptococcus mutans/efectos de los fármacos , Aglutinación , Cromatografía de Afinidad , Dextranasa/farmacología , Dextranos/farmacología , Calor , Lectinas/aislamiento & purificación , Lectinas de Plantas , Plantas , Streptococcus mutans/citología , Tripsina/farmacologíaRESUMEN
A model system for evaluating macroporous supports containing immobilized whole cells in affinity Chromatographic applications is described. Whole cells were immobilized in a polyacrylamide network in a two-step polymerization process. The affinity system discussed consists of immobilized cells ofSaccharomyces cervisiae in the purification of lentil lectin fromLens culinaris.
RESUMEN
A novel immunochemical method for the quantitation of bacterial cells is described. The method, which is based on separation of bound from free reactants in aqueous two-phase systems has been studied both as direct and competitive binding assays, with a system consisting of intact cells of Staphylococcus aureus and human immunoglobulin G molecules. To achieve high resolution, one of the reactants was modified so that the two reactants, the bacterial cells and the immunoglobulin molecules, occurred in different phases of the phase system. When binding takes place, the partition of one of the reactants is changed. The degree of change is then correlated to the amount of reactant present. Using this method, cell numbers in the region 10(5)-10(7) can be quantified. An assay takes 40-90 min.