Change in Emergency Department Length of Stay following Routine Adoption of Dual-Energy CT to Differentiate Intracranial Hemorrhage from Calcification

BACKGROUND AND PURPOSE: Dual-energy CT (DECT) is an advanced CT technique that has been shown to improve accuracy in distinguishing between intracranial hemorrhage and calcification, which is often challenging on conventional CT and therefore may warrant repeat imaging in the emergency department (ED) to document stability and exclude enlarging intracranial hemorrhage. We hypothesized that implementation of a DECT head protocol in the ED would decrease the need for repeat imaging and therefore reduce overall ED length of stay (LOS).

MATERIALS AND METHODS: This is a retrospective study comparing ED LOS over a 1-year period before (July 1, 2016 to June 30, 2017) and after (July 1, 2018 to June 30, 2019) implementing a DECT head protocol, for patients scanned for headache, trauma, or fall who were found to have indeterminate intracranial hyperdensities on conventional images, and were subsequently discharged home from the ED (excluding patients who were admitted, taken to the operating room, or left against medical advice). Additional clinical information regarding ED time course and management were also reviewed, including data on time to CT scan, CT report, and if applicable, time to repeat head CT and neurosurgical consultation.

RESULTS: There was no significant difference in patient demographics and CT indications between the pre-DECT and post-DECT cohorts. There was a small but statistically significant difference in mean baseline ED LOS in the initial cohorts of 20 minutes (P = .002). After the inclusion of only intracranial indeterminate hyperdensities, there was a larger statistically significant difference in ED LOS, with mean pre-DECT LOS of 421 minutes and mean post-DECT LOS of 272 minutes, resulting in mean LOS reduction of 149 minutes (P = .003). The increased ED LOS correlated with increased frequency of neurosurgical consultation and repeat head CT for the findings of indeterminate intracranial hyperdensities.

CONCLUSIONS: ED LOS was significantly longer in the pre-DECT cohort, which was partly attributable to neurosurgical consultation and repeat head CT performed for indeterminate intracranial hyperdensities.