Confusion

An umbrella term for puzzling or inappropriate behavior or responses, confusion is the inability to think quickly and coherently. Depending on its cause, confusion may arise suddenly or gradually and may be temporary or irreversible. Aggravated by stress and sensory deprivation, confusion commonly occurs in hospitalized patients—especially the elderly, in whom it may be mistaken for senility.

Sudden severe confusion combined with hallucinations and psychomotor hyperactivity is classified as delirium. Long-term, progressive confusion with deterioration of all cognitive functions is classified as dementia.

Confusion can result from fluid and electrolyte imbalance or from hypoxemia due to pulmonary disorders. It can also stem from metabolic, neurologic, cardiovascular, cerebrovascular, or nutritional disorders; a severe systemic infection; or the effects of toxins, drugs, or alcohol. Confusion also may signal worsening of an underlying and perhaps irreversible disease.

History and physical examination

When you take his history, ask the patient to describe what’s bothering him. He may not report confusion as his chief complaint but may complain of memory loss, persistent apprehension, or the inability to concentrate. He may be unable to respond logically to direct questions. Check with a family member or friend about the onset and frequency of the patient’s confusion. Find out, too, if the patient has a history of head trauma or a cardiopulmonary, metabolic, cerebrovascular, or neurologic disorder. Which medications is he taking, if any? Ask about any changes in eating or sleeping habits and in drug or alcohol use.

Perform an assessment to determine the presence of systemic disorders. Check vital signs, and assess the patient for changes in blood pressure, temperature, and pulse.

Next, perform a neurologic assessment to establish the patient’s level of consciousness.

Medical causes

Brain tumor

In the early stages of a brain tumor, confusion is usually mild and difficult to detect. As the tumor impinges on cerebral structures, however, confusion worsens and the patient may exhibit personality changes, bizarre behavior, sensory and motor deficits, visual field deficits, and aphasia.

Cerebrovascular disorders

These disorders produce confusion due to tissue hypoxia and ischemia. Confusion may be insidious and fleeting, as in a transient ischemic attack, or acute and permanent, as in a stroke.

Decreased cerebral perfusion

Mild confusion is an early symptom of decreased cerebral perfusion. Associated findings usually include hypotension, tachycardia or bradycardia, irregular pulse, ventricular gallop, edema, and cyanosis.

Fluid and electrolyte imbalance

The extent of the imbalance determines the severity of the patient’s confusion. Typically, he’ll show signs of dehydration, such as lassitude, poor skin turgor, dry skin and mucous membranes, and oliguria. He may also develop hypotension and a low-grade fever.

Head trauma

Concussion, contusion, and brain hemorrhage may produce confusion at the time of injury, shortly afterward, or months or even years afterward. The patient may be delirious, with periodic loss of consciousness. Vomiting, severe headache, pupillary changes, and sensory and motor deficits are also common.

Heatstroke

This disorder causes pronounced confusion that gradually worsens as body temperature rises. Initially, the patient may be irritable and dizzy; later, he may become delirious, have seizures, and lose consciousness.

Hypothermia

Confusion may be an early sign of this disorder. Typically, the patient displays slurred speech, cold and pale skin, hyperactive deep tendon reflexes, rapid pulse, and decreased blood pressure and respiratory rate. As his body temperature continues to drop, his confusion progresses to stupor and coma, his muscles become rigid, and his respiratory rate decreases.

Hypoxemia

Acute pulmonary disorders that result in hypoxemia produce confusion that can range from mild disorientation to delirium. Chronic pulmonary disorders produce persistent confusion.

Infection

A severe generalized infection, such as sepsis, commonly produces delirium. Central nervous system (CNS) infections, such as meningitis, cause varying degrees of confusion along with headache and nuchal rigidity.

Metabolic encephalopathy

Both hyperglycemia and hypoglycemia can produce sudden confusion. A patient with hypoglycemia may also experience transient delirium and seizures. Uremic and hepatic encephalopathies produce gradual confusion that may progress to seizures and coma. Usually, the patient also experiences tremors and restlessness.

Nutritional deficiencies

Inadequate dietary intake of thiamine, niacin, or vitamin B₁₂ produces insidious, progressive confusion and possibly mental deterioration.

Seizure disorders

Mild to moderate confusion may immediately follow any type of seizure. The confusion usually disappears within several hours.

Thyroid hormone disorders

Hyperthyroidism produces mild to moderate confusion along with nervousness, inability to concentrate, weight loss, flushed skin, and tachycardia. Hypothyroidism produces mild, insidious confusion and memory loss; weight gain; bradycardia; and fatigue.

Other causes

Alcohol

Intoxication causes confusion and stupor, and alcohol withdrawal may cause delirium and seizures.

Drugs

Large doses of CNS depressants produce confusion that can persist for several days after the drug is discontinued. Opioid and barbiturate withdrawal also causes acute confusion, possibly with delirium. Other drugs that commonly cause confusion include lidocaine, cardiac glycosides, indomethacin, cycloserine, chloroquine, atropine, and cimetidine.

Heavy metal poisoning

Chronic ingestion or inhalation of heavy metals (such as lead, arsenic, mercury, and manganese) eventually produces confusion and, typically, weakness and drowsiness. The patient may also experience headache, vomiting, seizures, tremors, gait disturbances, and mental deterioration.

Herb Alert

Special considerations

Never leave a confused patient unattended to prevent injury to himself and others. (Apply restraints only if necessary to ensure his safety.) Keep the patient calm and quiet, and plan uninterrupted rest periods. To help him stay oriented, keep a large calendar and a clock visible, and make a list of his activities with specific dates and times. Reintroduce yourself to the patient each time you enter his room.

Pediatric pointers

Confusion can’t be determined in infants and very young children. However, older children with acute febrile illnesses commonly experience transient delirium or acute confusion.

Book Source Details

• Book Title: Professional Guide to Signs & Symptoms (Fifth Edition)
• Author(s): Springhouse
• Year of Publication: 2006
• Copyright Details: Professional Guide to Signs & Symptoms (Fifth Edition), Copyright © 2006 Lippincott Williams & Wilkins.

Other Book Chapters Related to Confusion

Read excerpts from these other book chapters related to Confusion:

Copyright Details: Professional Guide to Signs & Symptoms (Fifth Edition), Copyright © 2008 Williams & Wilkins.

More About Causes of Confusion

• Back to symptom: Confusion: Introduction (review 725 causes)
• Next Book Extract About Confusion: Delirium (The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter)
• All Book Extracts: All Online Book Extracts for Confusion

More About This Book: Title: Professional Guide to Signs & Symptoms (Fifth Edition) Authors: Springhouse Publisher: Lippincott Williams & Wilkins Copyright: 2006 ISBN: 1-58255-510-9

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