Biosurveillance of ED visits for gastroenteritis.

OBJECTIVE: Our objective was to characterize emergency department (ED) visits for gastroenteritis by season and age and develop a predictive model. METHODS: We performed a retrospective cohort study of patients seen in 19 EDs from 1988 to 2002. We examined differences in the annual peaks of younger (<60 months) and older (>60 months) age groups and developed a time series regression model. RESULTS: Of the 5,182,019 total visits, 88,504 were for gastroenteritis. On average, the percentage of gastroenteritis on the peak days was higher in the younger (26%) than older group (4%), and the peaks for the younger group occurred 36 days after those for the older group. CONCLUSION: Emergency department visits for gastroenteritis vary greatly by season and age. Our time series predictive model was a good fit to actual incidence patterns. These variations should be accounted for in designing a system to detect bioterrorism and for surveillance of naturally occurring epidemics.

The effects of a physician slowdown on emergency department volume and treatment.

OBJECTIVES: In February 2003, many physicians in New Jersey participated in a work slowdown to publicize large increases in malpractice premiums and generate support for legislative reform. It was anticipated that the community physician slowdown (hereafter referred to as "slowdown") would increase emergency department (ED) visits. The authors' goal was to help others prepare for anticipated increases in ED volumes by describing the preparatory staffing changes made and quantifying increases in ED volume. METHODS: This was a retrospective cohort study performed at a New Jersey suburban teaching hospital with 70,000 annual visits. Consecutive patients seen by emergency physicians were enrolled. The authors extracted patient visit data from the computerized tracking system and analyzed hours worked by personnel, patient volumes, admission rates, and patient throughput times. Variables from each day of the slowdown with baseline values for the same day of the week for the four weeks before and after the slowdown were compared. A Bonferroni correction was used, with p < 0.01 considered statistically significant. RESULTS: Total patient volume increased 79% from baseline (95% confidence interval [CI] = 20% to 137%). Pediatric volume increased 223% (95% CI = 171% to 274%). Overall admission rate decreased 29% compared with baseline (95% CI = 8% to 51%). Patient throughput times did not change significantly. Similar results for these variables were found for the second through fourth days of the slowdown. CONCLUSIONS: Emergency department visits, especially pediatric visits, increased markedly during the community physician slowdown. Anticipatory increases in staffing effectively prevented increased throughput times.

Cardiac events in New Jersey after the September 11, 2001, terrorist attack.

The higher stress associated with the World Trade Center (WTC) attacks on September 11, 2001, may have resulted in more cardiac events particularly in those living in close proximity. Our goal was to determine if there was an increase in cardiac events in a subset of emergency departments (EDs) within a 50-mi radius of the WTC. We performed a retrospective analysis of consecutive patients seen by ED physicians in 16 EDs for the 60 days before and after September 11 in 2000-2002. We determined the number of patients admitted to an inpatient bed with a primary or secondary diagnosis of acute myocardial infarction (MI) or tachyarrhythmia. In each year, we compared patient visits for the 60 days before and after September 11 using the chi-square statistic. For the 360 days during the 3 years, there were 571,079 patient visits in the database of which 110,766 (19.4%) were admitted. Comparing the 60 days before and after September 11, 2001, we found a statistically significant increase in patients with MIs (79 patients before versus 118 patients after, P =.01), representing an increase of 49%. There were no statistically significant differences for MIs in 2000 and 2002 and in tachyarrhythmias for all three years. For the 60-day period after September 11, 2001, we found a statistically significant increase in the number of patients presenting with acute MI but no increase in patients admitted with tachyarrhythmias.