Utility of head computed tomography for older adults with suspected delirium in the emergency department: A retrospective observational study

Abstract

Background: Delirium in older people is associated with significant morbidity and mortality and has life-threatening etiologies making prompt recognition essential. Computed tomography of the head (CT-head) may have a role in determining the cause of delirium; however, inpatient studies suggest it is overused. There is a paucity of emergency department (ED)-based research surrounding the use of CT-head in delirium. This study aims to describe the utility of CT-head in older patients presenting to the ED with symptoms of delirium.

Methods: We conducted a retrospective chart review of patients 65 years and older with symptoms of delirium who visited local EDs over a 3.5-year period (2016-2020). We compared patients who did and did not receive CT-head. Our primary objective was to determine the proportion of acute findings in patients who received CT-head. Our secondary objectives were to describe the proportions of patients who did and did not receive CT-head in terms of their demographics, presenting symptoms, disposition, and indications for and results of CT-head scans. Chi-square tests were utilized for comparisons.

Results: A total of 630 encounters were identified through database searching; 526 met inclusion criteria. Thirty-four were excluded for presenting directly to consultants, leaving 492 included encounters. Of those who received a CT-head (n = 279), 13 (4.7%) had acute findings. Of the encounters with acute findings, four (30.77%) had focal neurological deficits (FND), and two (15.38%) had Glasgow Coma Scale (GCS) score < 14. Patients without CT-head (n = 213) were more likely to be discharged (p < 0.01) and less likely to have a FND (p < 0.01).

Conclusions: CT-head is ordered for over half of older ED patients with symptoms of delirium despite infrequent acute findings. Acute findings typically occur in the context of symptoms suggestive of intracranial abnormalities such as FND or GCS < 14. This suggests physicians should be more selective when ordering CT-heads in patients with symptoms of delirium.

Keywords: CT; computed tomography; delirium; emergency medicine; geriatrics.