An approach for the emergency diagnosis and treatment of sepsis-associated encephalopathy in elderly individuals: a literature review

doi:10.5847/wjem.j.1920-8642.2025.0101

Abstract

Abstract:

BACKGROUND: Sepsis-associated encephalopathy (SAE) is a diffuse dysfunction of the nervous system resulting from sepsis originating outside the central nervous system. Elderly individuals (≥65 years of age) constitute a particularly vulnerable population comprised by a high burden of underlying diseases and complications, which frequently leads to underdiagnosis or misdiagnosis. These patients are at increased risk of long-term or permanent central nervous system impairment, making rapid and accurate diagnosis and treatment especially critical. The review is expected to promote improvements in the diagnosis and treatment of SAE in elderly patients, ultimately achieving more standardized and efficient SAE management.

METHODS: We performed a literature search in four databases—PubMed, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang—from inception to April 2025 using bilinguals (Chinese and English).

RESULTS: The diagnostic criteria for SAE in elderly individuals include the following: (1) sepsis; (2) new-onset neurological dysfunction; and (3) exclusion of other causes of neurological dysfunction. Physicians should develop tailored empiric anti-infective plans for elderly SAE patients, considering comorbidities, organ function, infection site, local bacterial spectrum, and resistance. The treatment protocol can be adjusted once the pathogen is identified. Stabilizing hemodynamics and ensuring cerebral perfusion are two fluid resuscitation strategies used in elderly SAE patients. An individualized approach to fluid resuscitation using restrictive fluid volumes should be employed. Supportive treatment for elderly SAE patients focuses on improving tissue perfusion/oxygenation, controlling blood glucose levels, and correcting internal imbalances. Early rehabilitation, nutritional support, cognitive training, and family-based emotional support are important components of comprehensive care.

CONCLUSION: The diagnosis and management of SAE in elderly patients support early recognition and timely intervention.

Key words: Sepsis-associated encephalopathy, Elderly, Emergency, Diagnosis, Management

Wei Gu, Jie Zhong, Chuanzhu Lyu, Guoqiang Zhang, Miaorong Xie, Yuefeng Ma, Wei Guo. An approach for the emergency diagnosis and treatment of sepsis-associated encephalopathy in elderly individuals: a literature review[J]. World Journal of Emergency Medicine, 2025, 16(5): 415-422.

Figures/Tables 3

Table 1.

Differential diagnosis of sepsis-associated encephalopathy (SAE) and other conditions based on clinical features

Features	SAE	Stroke	Epilepsy	Metabolic encephalopathy
Disease onset and state of consciousness	• Synchronized with sepsis • Progressive impairment of consciousness • Delirium • Decreased concentration or orientation • Coma	• Acute onset (minutes to hours) • Sudden focal neurological deficits • Level of consciousness depends on lesion location (e.g., brainstem lesions may cause coma)	• Episodic (lasting seconds to minutes) • Loss of consciousness during the ictal phase (tonic-clonic seizures) • Normal consciousness between episodes	• Onset synchronized with metabolic disturbances (e.g., hyponatremia, liver failure) • Fluctuating levels of consciousness • Drowsiness progressing to coma
Neurological signs	• No focal neurological deficits • Diffuse hypertonia or hypotonia	• Focal deficits (e.g., hemiplegia, aphasia, visual field loss) • Positive pathological reflexes	• Tonic‒clonic seizures during the ictal phase • Postictal paralysis (Todd’s paralysis)	• Symmetrical tremor • Ataxia (e.g., Wernicke’s encephalopathy) • Asterixis (e.g., hepatic encephalopathy)
Accompanying symptoms	• Nausea and vomiting • Dyspnea	• Headache (suggestive of hemorrhagic stroke) • Vertigo (posterior circulation stroke) • Dysarthria or dysphagia	• Preictal auras (e.g., visual hallucinations, olfactory hallucinations) • Tongue biting • Urinary or fecal incontinence	Symptoms of underlying disease: • Jaundice (e.g., hepatic encephalopathy) • Polyuria/oliguria (e.g., renal failure) • Hunger pangs (e.g., hypoglycemia)
Accompanying signs	Signs of sepsis-associated organ failure: • Skin mottling • Acral cyanosis (hypoperfusion) • Decreased urine output	Vascular indicators: • Carotid bruit • Atrial fibrillation • Acute hypertension (hemorrhagic stroke)	Ictal indicators: • Mydriasis (tonic) • Tachycardia or apnea	Signs of metabolic disturbances: • Kayser-Fleischer rings (Wilson’s disease) • Signs of clinical dehydration (e.g., hyperosmolar coma) • Palmar erythema or spider angiomas (hepatic encephalopathy)

Table 1.

Table 2.

Figure 1.

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Types	Specific methods	Clinical significance
Laboratory and metabolic testing	• Blood and urine routine tests, electrolytes, liver and kidney function tests, blood glucose, blood gas analysis, serum lactate • Infection markers (e.g., PCT, CRP, HBP) • IL-1β and TNF-α • Etiological testing	• Aids in early detection of infection and systemic inflammatory response
Neuronal injury biomarkers	• NSE • S100β • GFAP • NfL	• Indicates neuronal or glial injury
Neuroelectrophysiological monitoring	• EEG	• Detects slow waves, epileptiform discharges, and suppressed brain activity; useful for monitoring and prognostication
Neuroimaging	• CT • MRI of the brain (e.g., DWI and FLAIR sequences)	• Excludes acute intracerebral hemorrhage and infarction; assesses structural abnormalities and white matter or microvascular damage
Other specialized tests	• CSF analysis (cell count, protein, glucose, etc.,) • Serum autoantibodies	• Helps exclude CNS infections, autoimmune encephalitis, and other specific encephalopathies

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