Meir Hillel Scheinfeld MD, PhD, Abstract Co-Author: Nothing to Disclose

Kevin Burns MD, Presenter: Nothing to Disclose

Victoria Chernyak MD, Abstract Co-Author: Nothing to Disclose

Predicting ED imaging volume would be helpful in scheduling radiologists and technologists. Our goal was to determine the relationship of triage volume, season, weather and day of the week on imaging volume.

IRB approval was obtained. The hospital database was queried for daily ED triage volume and imaging studies performed from 2011 through 2013 at a large tertiary care urban medical center. Daily weather conditions (temperature, amount and type of precipitation) were obtained from National Oceanic & Atmospheric Administration records. "Extreme weather" was defined as temperature <32ºF or >90ºF. Day of the week and season were recorded. Pearson correlations were first used to compare daily triage volume to imaging volume by modality. Logistic regression was used to arrive at parsimonious models with dichotomous outcomes of having high imaging volume, defined as days above the 90th percentile for a given modality. All models were adjusted for day of the week.

There were 485,295 ED triages and 305,493 imaging studies performed during the study period. Pearson correlations between triage volume and imaging modality yielded r=0.73 (p217 XR, >37 US or >73 CT exams. For every additional 50 triaged patients, the odds of having high XR volume increased by 4.3 times (95% CI 2.9-6.3, p<0.001), having high CT volume increased by 1.5 times (95% CI 1.1-2.1, p=0.02), and having high US volume increased by 1.4 times (95% CI 1.1-1.9, p=0.02). Extreme weather was associated with 1.8 times higher odds (95% CI 1.0–3.1, p=0.05) of having high CT volume. Compared to winter, spring was associated with 2.1 times higher odds (95% CI 1.1–3.8, p=0.02) of having high CT volume. Season and extreme weather were not independent predictors of high US or XR volume. Amount and type of precipitation were not independent predictors of high imaging volume for any modality.

Higher ED triage volume is strongly associated with high XR volume and, to a lesser extent, with high CT and US volume. Extreme weather is associated with increased odds of having high CT volume but not US or XR. Amount or type of precipitation were not associated with high imaging volume.

ED triage volume is the primary association of imaging volume, most prominently for radiography; therefore, factors which influence ED triages should be considered when determining radiology and technologist staffing.

Scheinfeld, M, Burns, K, Chernyak, V, Emergency Department Imaging Utilization: What Factors are Associated with High Imaging Volume?.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14009551.html