J Neurocrit Care.  2020 Dec;13(2):86-92. 10.18700/jnc.200010.

The etiologies of altered level of consciousness in the emergency department

• Jung S
• Jeon JC
• Jung CG
• Cho YW
• Kim KT

• KMID: 2509937
• DOI: http://doi.org/10.18700/jnc.200010

Abstract

Background
New-onset altered level of consciousness (ALC) is a common condition in patients visiting the emergency department (ED). We evaluated the clinical characteristics, causes, and prognosis of adult patients presenting with ALC at an ED of a university hospital to determine the etiologies, outcomes, and destinations of these patients.
Methods
The medical records of patients with ALC who visited the ED of a university hospital from February 2019 to January 2020 were reviewed. The cause of ALC and its classification were carefully decided by agreement through a discussion among board-certified clinicians in emergency medicine, neurology, and internal medicine.
Results
Of the 731 patients with ALC in the ED, whose mean age was 68.81±16.40 years, most were in their 80s (198, 27.09%). The most common etiology of ALC was systemic infection (30.78%), followed by metabolic causes (21.07%) and stroke (18.19%). Extracerebral and intracerebral etiologies of ALC in the ED accounted for 51.85% and 26.68% of the cases, respectively. The overall mortality of ALC in the ED was 17.67%. The largest number of ALC cases of 443 patients, i.e., 60.6% of all ALC patients in the ED were reported within the time zones of 11:00–12:00 and 07:00–19:00.
Conclusion
This study identified the extra-cerebral etiologies as the major causes of ALC in the ED.

Keyword

Altered level of consciousness; Consciousness; Emergency room; Emergency department

Figure

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  Fig. 1. Enrollment, destinations from emergency department (ED), and results of patients with altered level of consciousness (ALC). ICU, intensive care unit.

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  Fig. 2. Causes of altered level of consciousness in the emergency department. CNS, central nervous system.

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  Fig. 3. Cause analysis by time zone. TBI, traumatic brain injury; CNS, central nervous system.

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