Evaluation and treatment of altered mental status patients in the emergency department: Life in the fast lane

doi:10.5847/wjem.j.issn.1920-8642.2012.04.006

Abstract

Abstract:

BACKGROUND: Altered mental status (AMS) is a very common emergency case, but the exact etiology of many AMS patients is unknown. Patients often manifest vague symptoms, thus, AMS diagnosis and treatment are highly challenging for emergency physicians. The aim of this study is to provide a framework for the assessment of AMS patients. This assessment should allow providers to better understand the etiology of mental status changes and therefore improve diagnostic skills and management.

METHODS: This is a prospective cohort observational study. We recruited all adult patients with undifferentiated AMS at a single center tertiary care academic emergency department over 24 months (June 2009 to June 2011). Demographic characteristics, clinical manifestations, assessment approaches, causative factors, emergency treatments and outcomes were collected prospectively.

RESULTS: In 1934 patients with AMS recruited, accounting for 0.93% of all emergency department (ED) patients, 1 026 (53.1%) were male, and 908 (46.9%) female. Their average age was 51.95±15.71 years. Etiologic factors were neurological (n=641; 35.0%), pharmacological and toxicological (n=421; 23.0%), systemic and organic (n=266; 14.5%), infectious (n=167; 9.1%), endocrine/metabolic (n=145; 7.9%), psychiatric (n=71; 3.9%), traumatic (n=38; 2.1%), and gynecologic and obstetric (n=35; 1.9%). Total mortality rate was 8.1% (n=156). The death rate was higher in elderly patients (≥60) than in younger patients (10.8% vs. 6.9%, P=0.003).

CONCLUSIONS: Patients with AMS pose a challenge for ED physicians. The most frequently encountered diagnostic categories causing AMS were primary CNS disorders, intoxication, organ system dysfunction, and endocrine/metabolic diseases. AMS has a high fatality rate in the ED. AMS is an important warning signal for ED patients because of its potentially fatal and reversible effects. Prompt evaluation and treatment are essential to decreasing morbidity and mortality associated with AMS.

Key words: Altered mental status, Emergency department, Demographic characteristics, Clinical feature, Assessment, Etiology, Mortality, Algorithm

Hai-yu Xiao, Yu-xuan Wang, Teng-da Xu, Hua-dong Zhu, Shu-bin Guo, Zhong Wang, Xue-zhong Yu. Evaluation and treatment of altered mental status patients in the emergency department: Life in the fast lane[J]. World Journal of Emergency Medicine, 2012, 3(4): 270-277.

Figures/Tables 4

Figure 1.

Table 1

Table 2

Etiologic factors of AMS in different age groups (n=1 831)

Etiologic factors	Number of patients (%)	Age distribution n (%)		χ²	P value
Etiologic factors	Number of patients (%)	Non-elderly <60 years	Elderly ≥60 years	χ²	P value
Neurological causes	641 (35.0)	268 (24.9)	373 (49.3)	115.42	<0.001
Cerebrovascular disease	354 (19.3)	80 (7.5)	274 (36.2)	236.93	<0.001
Traumatic brain injury	133 (7.3)	84 (7.8)	49 (6.5)	1.20	0.274
Viral encephalitis	73 (4.0)	55 (5.1)	18 (2.4)	8.73	0.003
Seizures/epilepticus status	65 (3.5)	40 (3.7)	25 (3.3)	0.23	0.631
Intracranial tumors	16 (0.87)	9 (0.8)	7 (0.9)	0.04	0.844
Non-neurological causes	1 190 (65.0)	806 (75.1)	384 (50.7)	115.42	<0.001
Pharmacologic & toxicologic^?	421 (23.0)	375 (34.9)	46 (6.1)	208.58	<0.001
Acute alcohol intoxication	310 (16.9)	303 (28.2)	7 (0.9)	235.09	<0.001
Other factors	111 (6.1)	72 (6.7)	39 (5.2)	1.88	0.171
Systemic and organic dysfunction	266 (14.5)	119 (11.1)	147 (19.4)	24.87	<0.001
Lung	101 (5.5)	29 (2.7)	72 (9.5)	39.52	<0.001
Cardiovascular	79 (4.3)	41 (3.8)	38 (5.1)	1.56	0.212
Blood / immune	36 (2.0)	23 (2.1)	13 (1.7)	0.42	0.520
Kidney	31 (1.7)	13 (1.2)	18 (2.4)	3.64	0.057
Liver and gastrointestinal tract	19 (1.0)	11 (1.0)	8 (1.1)	0.01	0.946
Infectious factors^??	167 (9.1)	88 (8.2)	79 (10.4)	2.69	0.101
Metabolic / endocrine factors	145 (7.9)	97 (9.0)	48 (6.3)	4.41	0.036
Psychiatric problems	71 (3.9)	39 (3.6)	32 (4.2)	0.42	0.515
Multiple trauma	38 (2.1)	23 (2.1)	15 (2.0)	0.06	0.813
Gynecologic and obstetric	35 (1.9)	32 (3.0)	3 (0.4)	15.8	<0.001
John Doe syndrome^???	47 (2.6)	33 (3.1)	14 (1.8)	2.66	0.103
Adrenal insufficiency	13 (0.7)	9 (0.8)	4 (0.5)	0.60	0.437
Limbic encephalitis	6 (0.3)	5 (0.5)	1 (0.1)	——	——
Koyanagi-Harada syndrome	3 (0.2)	3 (0.3)	0	——	——
Anti-NMDA receptor encephalitis	1 (0.1)	1 (0.1)	0	——	——
Other	24 (1.4)	15 (1.4)	9 (1.2)	0.15	0.700
Total	1 831	1 074	757

Table 2

Figure 2.

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Clinical status	Number of patients (%)
Difficulties to arouse	1 025 (53)
Glasgow Coma Scale<15	851 (44)
Disorientation for time, space and/or people	696 (36)
Diminished responsiveness to verbal or physical stimulation	677 (35)
Confusions	522 (27)
Unable to remain awake or conversant	406 (21)
Bizarre or inappropriate behavior	174 (9)
Hallucinations	135 (7)
Other	58 (3)

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