Acute Confusional State (Delirium) in the Emergency Department: A Guide for Junior Doctors

Introduction

Acute confusional state, also known as delirium, is a sudden and severe disturbance in mental status that can be life-threatening if not promptly addressed. In the high-paced environment of the emergency department, recognizing and managing delirium is crucial. This blog post will guide you through the essential steps, from history taking to investigations and management, ensuring you are well-equipped to handle this common but complex condition.

History Taking: The Foundation of Diagnosis

When faced with a patient exhibiting confusion or disorientation, your first step is a thorough history. Here are the key areas to cover:

Onset and Course:

·      "When did the confusion start?" - Delirium typically has an acute onset, developing over hours to days.

·      "Was the onset sudden or gradual?" - A rapid onset suggests delirium, while a more gradual decline may point to dementia or other chronic conditions.

Baseline Cognitive Function:

·      "What was the patient's usual cognitive function?" - Compare the current state to the patient's baseline. This helps differentiate new-onset delirium from chronic cognitive impairments.

Associated Symptoms:

·      "Has the patient had any fevers, chills, or recent infections?" - Infections like urinary tract infections or pneumonia are common triggers, especially in older adults.

·      "Any recent head trauma, falls, or changes in mobility?" - Physical injury or immobility can contribute to delirium, particularly in the elderly.

·      "Has there been any recent change in medications?" - Polypharmacy, particularly the use of sedatives, anticholinergics, or opioids, is a common cause of delirium.

Substance Use:

·      "Does the patient consume alcohol or use recreational drugs?" - Delirium can result from withdrawal (especially alcohol or benzodiazepines) or intoxication.

·      "Is there a history of heavy drinking or drug dependence?" - This could indicate the potential for withdrawal syndromes.

Medical History:

·      "Does the patient have chronic conditions like liver disease, kidney disease, or diabetes?" - These conditions predispose patients to metabolic disturbances that can cause delirium.

·      "Any recent surgeries or hospitalizations?" - Postoperative delirium is particularly common in older patients.

Physical Examination: Clues to the Underlying Cause

A focused physical examination can provide critical information:

General Appearance and Vital Signs:

·      Assess the level of consciousness - Is the patient alert, lethargic, or stuporous?

·      Check vital signs - Fever, tachycardia, hypertension, or hypoxia may point to infection, sepsis, or respiratory failure.

Neurological Examination:

·      Perform a quick neurological assessment - Look for focal deficits that might suggest stroke or other central nervous system pathology.

·      Assess pupils, cranial nerves, and motor function - These can give clues to intracranial causes or medication effects.

Cardiovascular and Respiratory System:

·      Auscultate the heart and lungs - Listen for murmurs, crackles, or other abnormal sounds that might suggest cardiac or respiratory issues contributing to delirium.

Hydration and Nutrition:

·      Check for signs of dehydration or malnutrition - These are common, particularly in elderly or neglected patients.

Investigations: Pinpointing the Cause

Once you’ve gathered a thorough history and completed your examination, the next step is to order appropriate investigations. The goal is to identify reversible causes of delirium.

Laboratory Tests:

·      Full Blood Count (FBC) - Look for signs of infection, anemia, or hematologic disorders.

·      Urea and Electrolytes (U&E) - Electrolyte imbalances, such as hyponatremia, are frequent culprits in delirium.

·      Liver Function Tests (LFTs) - These are crucial if hepatic encephalopathy is suspected.

·      Blood Glucose Levels - Both hypoglycemia and hyperglycemia can precipitate delirium.

·      Thyroid Function Tests - Abnormal thyroid function can cause or exacerbate delirium.

·      Toxicology Screen - Essential if there is suspicion of substance misuse or poisoning.

·      Blood Cultures - Indicated if sepsis is on the differential, particularly in patients with fever or hypotension.

Imaging:

·      Chest X-ray - To rule out respiratory infections like pneumonia, which is a common trigger for delirium.

·      CT Head - If there is a history of trauma, focal neurological signs, or if an intracranial pathology like a hemorrhage or tumor is suspected.

Urinalysis:

·      Look for signs of a urinary tract infection - A common and treatable cause of delirium, especially in elderly patients.

Electrocardiogram (ECG):

·      To assess for arrhythmias or ischemic changes - Cardiac issues can often manifest as delirium, particularly in older adults.

Management: A Structured Approach

Managing delirium involves addressing the underlying cause, providing supportive care, and ensuring the safety of the patient.

Treat the Underlying Cause:

·      Infections - Start appropriate antibiotics if an infection is identified.

·      Metabolic Imbalances - Correct any electrolyte abnormalities or glucose imbalances.

·      Substance Withdrawal - Administer benzodiazepines or other appropriate agents for alcohol or benzodiazepine withdrawal.

Supportive Care:

·      Hydration and Nutrition - Ensure the patient is adequately hydrated and receiving proper nutrition.

·      Environmental Modifications - Create a calm, well-lit environment. Reduce sensory overload by minimizing noise and ensuring the presence of familiar objects.

·      Frequent Reorientation - Reassure and reorient the patient regularly. Use clocks, calendars, and clearly visible windows to help ground them in reality.

Medication Review:

·      Discontinue or reduce any non-essential medications - Particularly those with anticholinergic properties, which can exacerbate delirium.

·      Consider short-term use of antipsychotics - Only if the patient is severely agitated and poses a risk to themselves or others. Use the lowest effective dose for the shortest duration possible.

Monitoring and Follow-up:

·      Frequent reassessment - Regularly check the patient’s cognitive status and adjust the management plan as needed.

·      Involve the family - Keep the patient’s family informed and involved in care decisions, as they can provide valuable information and support.