Socioeconomic composition of low-acuity emergency department users in Ontario.

OBJECTIVE: To describe the associations between the socioeconomic status of emergency department (ED) users and age, sex, and acuity of medical conditions to better understand users' common characteristics, and to better meet primary and ambulatory health care needs. DESIGN: A retrospective, observational, population-based analysis. A rigorous proxy of socioeconomic status was applied using census-based methods to calculate a relative deprivation index. SETTING: Ontario. PARTICIPANTS: All Ontario ED visits for the fiscal year April 1, 2008, to March 31, 2009, from the National Ambulatory Care Reporting System data set. MAIN OUTCOME MEASURES: Emergency department visits were ranked into deprivation quintiles, and associations between deprivation and age, sex, acuity at triage, and association with a primary care physician were investigated. RESULTS: More than 25% of ED visits in Ontario were from the most deprived population; almost half of those (12.3%) were for conditions of low acuity. Age profiles indicated that a large contribution to low-acuity ED visits was made by young adults (aged 20 to 30 years) from the most deprived population. For the highest-volume ED in Ontario, 94 of the 499 ED visits per day were for low-acuity patients from the most deprived population. Most of the highest volume EDs in Ontario (more than 200 ED visits per day) follow this trend. CONCLUSION: Overall input into EDs might be reduced by providing accessible and appropriate primary health care resources in catchment areas of EDs with high rates of low-acuity ED visits, particularly for young adults from the most deprived segment of the population.

Effect of iron type on kinetics and carbon isotopic enrichment of chlorinated ethylenes during abiotic reduction on Fe(0).

Four samples of two commercially available iron brands used as substrate for iron permeable reactive barriers (PRBs) were tested for suitability for remediation of perchloroethylene (PCE), trichloroethylene (TCE), cis-dichloroethylene (cDCE) and vinyl chloride (VC). Kinetic studies indicate that rates of reaction are enhanced for cDCE and VC on Connelly iron (2.8 x 10(-4) to 6.9 x 10(-4) L/m2/hr and 2.0 x 10(-4) to 9.0 x 10(-4) L/m2/hr, for cDCE and VC, respectively) vs. Peerless iron (3.1 x 10(-5) to 4.6 x 10(-5) L/m2/hr and 2.4 x 10(-5) to 4.1 x 10(-5) L/m2/hr, for cDCE and VC, respectively). Carbon isotopic analyses of the residual chlorinated ethylene (CE) during degradation indicate significant fractionation occurs during reductive dechlorination, with, for example, up to 70% enrichment in carbon isotopic values observed when VC is more than 99% degraded. Comparison of fractionation factors (epsilon) indicates significant differences in carbon isotopic fractionation for different iron types and for different CEs. For the lower CEs (cDCE and VC) in particular, both slower reaction rates and larger fractionation are observed for degradation on Peerless vs. Connelly iron. This is the first study to establish a correlation between the rate of abiotic degradation on Fe(0) and the extent of isotopic fractionation, and the first to confirm consistent differences in these two parameters as a function of iron type. The possibility that these differences in kinetics and carbon isotopic fractionation for cDCE and VC are related to differences in branching ratios between competing hydrogenolysis and beta-elimination reactions during reductive dechlorination on the iron surfaces is discussed.