Altered mental status in children is characterized by the failure to respond to verbal or physical stimulation in a manner appropriate to the child’s developmental level. The ED incidence of altered mental status in children varies widely depending on the type of institution reporting, the patient population served, and the specific definition of altered mental status used.1,2 Children with altered mental status require simultaneous stabilization, diagnosis, and treatment. The objectives of treatment are to sustain life and prevent irreversible CNS damage. Once the patient is resuscitated, the goal is to determine the cause and stop disease progression.
Arousal is mediated by the neural pathways of the ascending reticular activating system that project from the brainstem to the hypothalamus, thalamus, and cerebral cortices. The ascending reticular activating system regulates wakefulness in response to the environment, as well as homeostasis, cardiovascular, and respiratory functions. Altered mental status occurs through dysfunction of the ascending reticular activating system, an insult to bilateral cerebral cortices, or global depression of the central nervous system.3,4 There are many factors that can cause dysfunction in the ascending reticular activating system and cerebral hemispheres, including inadequate substrate for metabolic demand, insufficient blood flow, presence of toxins or metabolic waste products, or alterations of body temperature.4 Typical causes of bilateral cortical impairment are toxic and metabolic states that deprive the brain of normal substrates.
There are multiple pathologic conditions that affect awareness and arousal; etiologies can initially be described as traumatic or nontraumatic. Nontraumatic causes can be further divided into structural and functional lesions. Structural lesions can be categorized as supratentorial or subtentorial. Signs and symptoms of supratentorial lesions include focal motor abnormalities, which are often present from the onset of the altered level of consciousness. Subtentorial lesions lead to reticular activating system dysfunction, in which prompt loss of consciousness is common. Cranial nerve abnormalities are frequent, and abnormal respiratory patterns are seen. Functional etiologies include infectious/inflammatory, metabolic/nutritional/toxic, and neurologic/psychiatric disorders. Depressed consciousness is typically seen before motor signs become depressed, and when present, motor deficits are typically symmetric.5
CLINICAL FEATURES AND APPROACH
The spectrum of alteration of mental status ranges from confusion or delirium (disorders in perception) to lethargy, stupor, and coma (states of decreased awareness). A lethargic child has decreased awareness of self and the environment. Patients may be aroused from an apparent deep sleep, but they immediately relapse into a state of minimal responsiveness. A stuporous child has decreased eye contact, decreased motor activity, and unintelligible vocalization. Stuporous patients can be aroused with vigorous noxious stimulation. Comatose patients are unresponsive and cannot be aroused by verbal or physical stimulation, such as phlebotomy, arterial catheterization, or lumbar puncture.6
Rapidly assess and support the airway, ventilation, and circulation. When the patient is stabilized, take a methodical and comprehensive history (Table ...