0071643192.pdf

ALTERED MENTAL STATUS

Confusional states can be broadly divided into delirium,dementia,andpsy-
chosis(see Table 15.8).

Delirium

In delirium, functions of cognition and attention (arousal) are disordered due
to widespread neuronal or neurotransmitter malfunction from an underlying
medical (organic) cause.

CAUSES

Common causes include:

■ Drug intoxication or withdrawal (most common)
■ Metabolic disorders (eg, endocrine disorder, hepatic encephalopathy, uremia,
hypoglycemia)
■ Toxins (eg, carbon monoxide)
■ Infections (eg, CNS, UTI, sepsis)
■ Hypercapnia
■ Trauma
■ Seizures

SYMPTOMS/EXAM

■ Acuteconfusional state
■ Transient attention and cognition impairment

NEUROLOGY

Delirium is a medical

emergency.

TABLE 15.8. Features of Delirium, Dementia, and Psychiatric Psychosis

CHARACTERISTIC DELIRIUM DEMENTIA PSYCHIATRIC

Onset Over days Insidious Sudden

Course over 24 hr Fluctuating Stable Stable

Consciousness Reduced Alert Alert

Attention Disordered Normal May be disordered

Cognition Disordered Impaired May be impaired

Orientation Impaired Often impaired May be impaired

Hallucinations Visual and/or auditory Often absent Usually audiotory

Delusions Transient, poorly Usually absent Sustained

organized

Movements Asterixis, tremor may Often absent Absent

be present

(Reproduced, with permission, from Tintinalli, J et al. Emergency Medicine: A Comprehensive
Study Guide, 6th ed. New York: McGraw-Hill, 2004:229; based on data from Lipowski Z: Delirium
in the Elderly Patient. New Engl J Med320:578,1989.)