Indoor Air Quality Determination And Analysis In Different Grade Hospitals In City

Objective:To study the indoor air quality and conditions between different departments of hospitals at different levels in different seasons,and whether it can meet the national requirements compared with national standards.At the same time,different seasons,different hospitals,different departments of the mutual comparison,analysis of the reasons for the differences.The correlation between the indoor pollution index and the number of bacteria and the basic index of indoor environment was studied and the causes of pollution were analyzed.To study the relationship between bacterial resistance in hospital indoor air and respiratory tract bacterial resistance and the use of antibiotics.Methods:to choose a city three levels of hospitals outpatient emergency respiratory ward of the three departments,spring and summer and autumn/winter two season,with a quick inspection method to investigate the index of indoor air,air quality analyzer test air pressure,temperature,moisture,wind speed,air volume,carbon dioxide,the concentration of volatile organic compounds,particulate matter analyzer measuring PM_2.5 and PM₁₀ content.The evaluation was conducted according to national standard GB15982-2012.Indoor air bacteria were sampled by air plate sampling method,and gram-staining was conducted after 48h culture for bacterial classification.Subsequently,a series of biochemical experiments,monosaccharide fermentation experiments and hydrogen peroxide experiments were carried out to identify and count specific pathogenic bacteria.AST drug sensitivity analyses the resistance of certain bacteria.Single sample T test was used to compare the pass rate between the measurement index and the national standard in different levels of hospitals and different departments.Univariate ANOVA and multivariate Chi-square tests were used to compare the differences in indoor environmental indicators between autumn and winter,between different levels of hospitals,and between different departments of the same hospital.The differences were also analyzed for the influence of which level of factors and the proportion of influences.Statistical analysis was conducted on the number results of different types of bacteria and pathogenic bacteria after biochemical experiment counting,and whether there were differences between different hospitals,different seasons,and different departments.The correlation between the measured index and the basic index of indoor environment was studied by means of atypical correlation analysis.GLMM multi-layer linear model was used to analyze the fixed and random effects of seasons and departments on indoor air bacteria count.The ggplot2 of R was used to draw the correlation coefficient graph of each index.Multiple linear regression and multiple logistic regression were used respectively to analyze the influence of changes in indicators on air bacteria count,with air bacteria count as the dependent variable and the variable with low collinearity among correlation coefficients as the independent variable.Results:Compared with the national standard,the pass rate of the first level hospitals is the lowest.In different departments,wards have the lowest pass rate.In the comparison of the pass rate of different seasons,the pass rate of spring and summer is lower.The pass rate of CO₂content has been low in different environments.The results of univariate ANOVA and multivariate chi-square test showed that there were significant differences in the number of bacteria in different levels of hospitals,P<0.05,and the difference was statistically significant,while the difference in other measurement indicators was not statistically significant.The analysis of the source results of the differences showed that the influence of the partial Eta formula on the number of bacteria and the content of CO₂was the highest by the hospital level,the influence of PM_2.5and PM₁₀ indexes was the highest by the department,and the influence of the volatile organic compounds was the highest by the seasonal factors.The correlation analysis showed that the hospital level increased,the number of bacteria,PM_2.5concentration and PM₁₀concentration all decreased.With the change of seasons from autumn and winter to spring and summer,namely the increase of temperature,PM_2.5concentration and PM₁₀concentration all increase,while VOC concentration and wind volume decrease.Single variable analysis showed that CO₂ concentration and VOC concentration were positively correlated.Humidity has a significant positive correlation with the number of air bacteria.The number of gram-positive cocci,Gram-negative cocci,Gram-positive bacilli and Gram-negative bacilli in different grade hospitals and in different departments of the same hospital was significantly different,P<0.05,the difference was statistically significant.Statistical analysis of pathogenic bacteria count showed that there was no significant difference in the number of pathogenic bacteria in different seasons,hospitals of different levels and departments.The pathogenic bacteria in hospitals showed varying degrees of resistance to the drugs of penicillin,Escherichia coli to tetracycline,pseudomonas aeruginosa to cephalosporins.The results of the fixed effect of GLMM multilayer mixed linear model showed that there were significant differences in the number of bacteria in the air between the first and third level hospitals in this sample,and the fixed effect between departments showed significant differences in the number of bacteria in the outpatient department and the ward.The random effect showed that the overall characteristics could be inferred from the sample characteristics and extended to all individuals,and the number of airborne bacteria in different levels and departments was statistically significant.The cross-level interactive multi-layer mixing model showed that there were differences in the number of airborne bacteria in different levels of hospitals in different seasons,P<0.05,and the difference was statistically significant.Specific analysis of what index changes caused the difference in the number of bacteria.Multiple linear regression results showed that the significance of hospital level,humidity and outdoor PM_2.5 index was less than 0.05,indicating a strong linear relationship with the number of bacteria and a strong explanatory ability.Multiple logistic regression results showed that grade and temperature were significant.For a one-unit increase in hospital level,the risk of bacterial count disqualification is 0.225 times higher than that of the next unit;for a one-unit increase in temperature,the risk of bacterial count disqualification is 0.543 times higher than that of the next unit.Conclusion:Compared with hospitals of different levels,the lower qualified rate of bacteria number in first-level hospitals is due to the inadequate disinfection equipment in first-level hospitals,the lack of equipment with higher disinfection intensity,and the insufficient ventilation.In the comparison of departments,the pass rate of wards was the lowest,due to the more intensive flow of people and beds.In the comparison of seasons,the pass rate of spring and summer is lower,and the increase of temperature will make the bacteria more easily to reproduce.At the same time,due to the inadequate indoor ventilation conditions in the hospital and the use of central air conditioning,the pass rate of CO₂ in each environment has been low.According to the correlation between the number of bacteria,controlling the number of bacteria can improve the wind speed by reducing the humidity of the room.The concentration of CO₂ and VOC in the ward can be improved by increasing the ventilation.The concentration of CO₂ and VOC in the ward can be adjusted by decreasing the humidity,increasing the wind speed,increasing the ventilation and decreasing the concentration of CO₂ and VOC in the ward.There were differences in the number of bacteria among different departments of hospitals at different levels,and GLMM model random effect showed that the differences in the number of bacteria among different levels were universal.The result of the analysis of bacterial species and the number of pathogenic bacteria shows that the reason for the high number of bacteria in first-level hospitals is mainly the increase of other bacteria,rather than the increase of pathogenic bacteria.The results of drug resistance analysis showed that it was related to the frequent use of such drugs in clinical treatment of related diseases.It was suggested that antibiotics should be used rationally to reduce the drug resistance of hospital bacteria.