ABSTRACT
Objective:To evaluate the association between the use of emergency medical services (EMS) and the severity of disease among patients admitted to the emergency room, to analyze the characteristics of the patients, and to build prediction model providing evidence-based use of EMS resources.Methods:The data of patients admitted to the Emergency Room of the First Affiliated Hospital of University of Science and Technology of China from January 2020 to July 2021 were extracted from the Chinese Emergency Triage Assessment and Treatment (CETAT) database. Patients were divided into the EMS use group (AB+ group) and self-seeing group (AB-group) according to whether they used EMS. The patients’ general condition, vital signs and laboratory tests results were recorded. The severity of patients’ condition was judged based on whether the patient was admitted to the department of critical medicine, specialized care unit, emergency operation and/or emergency percutaneous intervention. A 9-variable model that did not require laboratory inspection and 22-variable model that required laboratory inspection were established to correct the propensity score to analyze the correlation between the severity of disease and the EMS use. In the subgroup analysis, the correlation between the EMS use and severity of the patients was analyzed according to the reason of the patient’s visit.Results:During the study period, 16 489 patients were admitted to the emergency room, and 6975 patients were finally enrolled in this study. There were 2768 patients (39.7%) in the AB+ group and 4207 patients (60.3%) in the AB-group. In the AB+ group 522 patients (18.9%) were in high risk, and in the AB-group 563 patients (13.4%) were in high risk. Compared with the AB-group, patients in the AB+ group were older and had a higher proportion of coma, a faster autonomic heart rate, and a lower diastolic blood pressure and peripheral oxygen saturation (SpO 2). In the 9-variable model, sex, consciousness, temperature, heart rate and diastolic blood pressure were associated with the EMS use. In the 22-variable model, consciousness, SpO 2, neutrophils, and albumin were the relevant factors for patients using EMS. Before the correction of propensity score, the EMS use was an independent risk factor for critically ill patients ( OR=1.5, 95% CI 1.32-1.72, P<0.001). After adjusted using 9-variable propensity score, the EMS use ratio decreased significantly compared with that without correction ( OR=1.24,95% CI 1.08-1.42, P<0.001). Interestingly, after adjusted with propensity score match with 22-variable model, there was no association between the severity of disease and t the EMS use ( OR=1.10,95% CI 0.95-1.28, P=0.195). In subgroup analysis, patients’ chief complaint of central nervous system, cardiovascular system, and trauma were the top three reasons at admission. Before the propensity score correction, the EMS calling patients with chief complaint of central nervous system, digestive system, and trauma were related to the severity of the patients. After adjusted with 9-variable model the EMS use was associated with the severity of the disease only in trauma patients, and after adjusted with 22-variable model there was no statistical difference considering the severity of the disease in all subgroups. Conclusions:The EMS use is common. However, the association of the EMS use with the severity of disease is decreased with variable models using propensity score. These findings indicate that the EMS use should be based on multivariable models, which may be important in detecting critically ill patients, optimizing the EMS use, and avoiding unnecessary call in the future.
ABSTRACT
Objective@#To investigate the current status of the occupational hazards of welding fume, manganese, and manganese compounds in the welding environment of a large container manufacturing enterprise, as well as the status of occupational health examination of workers, and to provide a basis for improving the welding environment of this enterprise.@*Methods@#In August 2016, July 2017, and August 2018, convenience sampling was used to perform an on-site occupational hygiene survey of the welding workshop for three consecutive years, and welding fume, manganese and, manganese compounds (counted as manganese dioxide) were measured for their workplace exposure concentrations and exposure levels in workers. A comprehensive analysis was performed for the results of occupational health examination.@*Results@#Welding fume, manganese, and manganese compounds in the welding environment gradually increased from 2016 to 2018 (χ2trend=5.14 and 5.54, P<0.05). The maximum over-standard rate of concentration-short term exposure limit was 43.3% (13/30) for welding fume and 40.0% (12/30) for manganese and its compounds, and the maximum over-standard rate of time-weighted average concentration was 26.7% (8/30) for welding fume and 23.3% (7/30) for manganese and its compounds. Abnormalities were observed in the occupational health examination of welding workers in 2016-2018, among which respiratory system abnormalities (cough, expectoration, and wheezing), nervous system abnormalities (dizziness, fatigue, sleep disorders, amnesia, hyperhidrosis, and palpitations), and electrocardiogram abnormalities (bundle conduction block) had an incidence rate of above 10.0%, and the incidence rate of abnormalities on posterior-anterior X-ray high-kV chest radiograph was close to 8.9% (30/336) .@*Conclusion@#There is severe exposure to welding fume, manganese, and manganese compounds among workers in this enterprise, which cause great hazards to the health of workers. It is necessary to strengthen occupational health management, take measures to improve the welding environment, and enhance occupational disease prevention.
ABSTRACT
Objective@#To establish a method for determination of methyl ethyl ketone in urine by headspace gas chromatography.@*Methods@#In the urine sample(hereinafter referred to as urine sample), methyl ethyl ketone is pretreated by headspace technology, and a certain amount of head air is injected into the gas chromatograph, separated by capillary column, detected by hydrogen flame ionization detector, and the retention time is qualitative and the peak height is high. Peak area.@*Results@#Good linearity was in the range of 0.01 to 6.0 μg/ml with a regression equation of y=13.316x+0.8497 and γ=0.9997.The minimum detectable concentration of methyl ethyl ketone was 0.01 μg/ml. The range intra-day RSD and inter-day RSD were 2.2%-5.5% and 2.5%-6.1% respectively. Urine samples can be stored for 20 days in the refrigerator at 4 ℃.@*Conclusion@#The method has a high advantage of sensitivity and accuracy, and also easy to operate. Therefore, it is suitable for the determination of methyl ethyl ketone in urine.
ABSTRACT
OBJECTIVE: To establish a method for detecting triphenyl phosphate( TPP) in the workplace air by gas chromatography. METHODS: TPP in the air of workplace was collected with glass fiber filter paper,desorbed with ether,separated by HP-5 gas chromatographic column,and detected by flame photometric detector. RESULTS: This method has good linear range of 12. 50-800. 00 mg/L,with the correlation coefficient of 0. 999 9. The detection limit was 0. 78 mg/L,and the minimum detectable concentration was 0. 09 mg/m3(sample volume was 45 L). Desorption efficiency was 97. 2%-99. 4%; standard recovery rate was 99. 5%-100. 3%. The within-run relative standard deviation( RSD) was 2. 7%-3. 4%and the between-run RSD was 1. 4%-3. 2%. The sampling efficiency was 99. 6%-100. 0%. The samples could be stored at room temperature for at least 14 days. CONCLUSION: The method is simple,accurate and highly sensitive for detecting TPP in workplace air.
ABSTRACT
Objective@#To establish a method for the determination of diethyl phthalate by gas chromatography in the air of workplaces.@*Methods@#Diethyl phthalate in the air of workplace was collected throμgh glass fiber filter, eluted with methylbenzene, and detected by gas chromatography coupled with FID detectors.@*Results@#The linear range of diethyl phthalate determined by this method was 14.0~1 400 μg/ml, y=2.09801x-3.66229, and the coefficient correlation was 0.999 99. The detection limit was 1.10 μg/ml, and the minimum detection concentration was 0.18mg/m3 (collected sample volume was 30 L) . The within-run precisions were 1.04%~2.75%, and the between-run precisions were 0.34%~1.30%. The recovery rates were 98.72%~103.21%, and sampling efficiency was 97.2%~100.0%. The elution efficiencies were 97.25%~98.68%. The samples could be stored at room temperature for 15 days.@*Conclusion@#The indicators established in this study were conformed with the requirements of GBZ/T210.4-2008, "The Guidelines for the Development of Occupational Hygiene Standards Methods Part 4: Determination of Chemical Substances in the Air of Workplaces" . Diethyl phthalate in the workplace air could be rapidly collected, accurate separated and determinated. This method is applicable to the determination of diethyl phthalate in the workplace air.
ABSTRACT
OBJECTIVE: To formulate a limit of occupational benzoquinone in the air of workplace. METHODS: According to GBZ/T 210. 1-2008 Guide for Establishing Occupational Health Standards--Part 1: Occupational Exposure Limits for Airborne Chemicals in the Workplace,the relevant literatures on toxicology,epidemiology and foreign occupational exposure limit for benzoquinone were collected and analyzed. A benzoquinone production enterprise was selected as the research subject. Occupational hygiene investigation and occupational epidemiological investigation were carried out. The occupational exposure limit of benzoquinone in the air of workplace was assessed. RESULTS: The literature data analysis results showed that benzoquinone is a highly toxic substance,has strong stimulated effect on human respiratory tract,eyes and skin. The occupational exposure limit of benzoquinone in the workplace air in the United States of America,Germany and Australian is 0. 400 mg/m~3. In the benzoquinone production enterprise,the median of concentration-time weighted average of benzoquinone exposed workers( exposure group) was 0. 100 mg/m~3. The median of concentration-short term exposure limit in the workplace air was 0. 160 mg/m~3. There was no significant difference on the abnormal detection rate of conjunctivitis,dermatitis,and abnormal liver B type and abnormal kidney B type ultrasound between the exposure group and the control group( P > 0. 05). There was no significant difference on the serum liver function and renal function indexes between the two groups( P > 0. 05). The results of blood routine examination in the two groups were within the normal reference range. CONCLUSION: It is suggested that the permissible concentration-time weighted average of benzoquinone in the workplace air should be set at 0. 400 mg/m~3 in China.
ABSTRACT
Objective@#To establish a practical method forsampling and detectingtributyl phosphate intheworkplace.@*Methods@#The samples were extracted by glass fiber membrane, eluted with ether, separated by gas chromatography, and detected by flame photometric detector.@*Results@#There were good linear relationship in the minimum detection concentration was 7.2-720.0 μg/ml, and the correlation coefficient was 0.999 92. The detection limit was 0.86 μg/ml, and the minimum detection concentration was 0.14 mg/m3 (sample volume was 30 L) . Recovery rates were 99.8%-100.2%. The with-in relative standard deviations were 4.0%-5.4% and the between relative standard deviations were 2.0%-5.5%, and average samplingefficiency was about 99.1%-100.0%.@*Conclusion@#This method conforms with the requirements of "Standardization of Methods for Determination of Toxic Substance in Workplace" . Tributyl phosphate in air could be determined accurately using this method.
ABSTRACT
<p><b>OBJECTIVE</b>To establish a method for determination of 2,5-hexanedione in urine by headspace solid-phase microextraction-gas chromatography.</p><p><b>METHODS</b>After extraction by solid-phase microextraction head, 2,5-hexanedione in urine was determined by gas chromatography and was quantified by external standard method.</p><p><b>RESULTS</b>The concentration of 2,5-hexanedione in urine showed a linear relationship within the range of 0.1-20.0 µg/ml. The regression equation was y=261.36x-1.903 3, r=0.999 2. The minimum detectable concentration was 0.01 µg/ml. The recovery rate was 92.6%-97.1%, with a relative standard deviation (RSD) of 3.3%-5.8%. The intra-day and inter-day RSDs were 3.8%-6.2% and 4.7%-6.3% respectively.</p><p><b>CONCLUSION</b>This determination method has no requirement for organic solvents, features simple and rapid operation, possesses higher detection sensitivity, and applies well to the determination of 2,5-hexanedione in urine.</p>