What is Delirium - Types, Symptoms, and Causes

What is Delirium - Types, Symptoms, and Causes
Written By: Counselling Psychologist
M.Sc. Psychology - Swansea University, UK.
Reviewed By: Counselling Psychologist
MA Psychology Pennsylvania State University, USA
Last Updated: 31-03-2023

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Delirium is a state represented by a group of symptoms rather than a disease.  Delirium is a serious condition that can cause confusion and disorientation. It can be caused by several different things, including infections, medications, or an underlying medical condition. A typical delirium episode involves severe and sudden brain changes which lead a person to a state where thinking is unclear, attention is not focused, and recent events cannot be remembered. It is commonly seen in ICU, Extensive care wards and patients been on sedation for a long period.

Delirium is often confused with dementia. Delirium is different from dementia in that it is usually short-term and reversible, while dementia is a long-term degenerative disorder. The two are distinguished on the basis of onset, cause, attention, and fluctuations in symptom visibility. People with delirium often experience changes in their mental state, such as difficulty concentrating or understanding what is going on around them. They may also have trouble sleeping, become agitated or aggressive, or hallucinate or have delusions. A person with dementia may have delirium but a person with a delirium episode may not necessarily have dementia. Understanding the difference between delirium and dementia can help to ensure that people receive the right treatment for their condition.

Delirium is a medical condition that is characterized by an acute disturbance in mental functioning and awareness. It can be caused by a variety of underlying medical conditions, such as infections, medications, or trauma. It is most common in elderly people and can cause confusion, disorientation, and changes in behaviour. It is important to recognize the signs of delirium early so that it can be treated quickly and effectively.

Types of Delirium

Delirium is a medical condition characterized by an altered mental state that can cause confusion, disorientation, and impaired thinking. It can be caused by a variety of factors, including infection, drugs or alcohol, and physical or emotional stress. There are three main types of delirium: hyperactive delirium, hypoactive delirium, and mixed delirium.

Hyperactive Delirium

Hyperactive delirium is a serious medical condition that can occur when a person is exposed to certain drugs or experiences extreme physical or emotional stress. It is characterized by restlessness, agitation, disorientation, confusion, and poor coordination. In severe cases, hyperactive delirium can lead to seizures and even death if left untreated.

Treatment for this condition typically includes sedative medications and supportive care to reduce the symptoms and prevent further complications.

Hypoactive Delirium

Hypoactive delirium is a medical condition that is characterized by a decreased level of consciousness, confusion, disorientation, and inability to focus. It can be caused by an underlying medical condition such as infection, stroke, or trauma. It can also be caused by certain medications or substance abuse.

Symptoms of hypoactive delirium include reduced alertness and responsiveness to stimuli, slowed reaction time and speech, difficulty focusing on tasks and changes in sleep patterns. Treatment for hypoactive delirium typically includes managing the underlying cause of the condition as well as providing supportive care such as ensuring adequate nutrition and hydration.

Mixed Delirium

Mixed delirium, also known as "double delirium", is a condition characterized by the presence of both hypoactive and hyperactive features. It is a rare but serious condition that can cause confusion, disorientation, and other cognitive impairments.

The exact cause of mixed delirium is not known but it can be caused by an underlying medical illness, drug intoxication, or withdrawal from certain medications. Treatment for mixed delirium usually involves identifying and treating the underlying cause, as well as providing supportive care. Early diagnosis and treatment are important to prevent further complications.

Symptoms of Delirium

The symptoms of delirium often fluctuate throughout the day, and there may be periods of no symptoms. The symptoms usually tend to be worse after sunset and in a less familiar setting. A delirium episode has an effect on all aspects of an individual. Some of the symptoms are-

  • An inability to stay focused on a topic or to switch topics.

  • Getting stuck on an idea rather than responding to questions or conversations or being easily distracted by unimportant things.

  • Being quiet and withdrawn.

  • Cognitive impairment includes poor memory, particularly of recent events.

  • Disorientation — for example, not knowing where you are or who you are.

  • Difficulty in speaking with rambling or nonsense speech.

  • Trouble understanding speech.

  • Difficulty reading or writing.

  • Hallucinations, restlessness, agitation, or combative behaviour.

  • Calling out, moaning, or making other sounds.

  • Slowed movement or lethargy.

  • Disturbed sleep habits such as a reversal of the night-day sleep-wake cycle.

  • Emotional disturbances such as Anxiety, fear or paranoia, and Depression.

  • Rapid and unpredictable mood shifts, and

  • Personality changes.

Possible Causes for Delirium

Delirium is a sudden change in mental status that can cause confusion, disorientation, and other cognitive disturbances. It is a common condition in elderly individuals and can be caused by a variety of medical conditions and medications.

Delirium occurs when the normal sending and receiving of signals in the brain become impaired. This impairment is most likely caused by a combination of factors that make the brain vulnerable and trigger a malfunction in brain activity.  Some common causes of delirium in the elderly include infections such as urinary tract infections or pneumonia, electrolyte imbalances, dehydration, changes in blood pressure or heart rate, metabolic disorders such as diabetes or hypoglycemia, drug reactions or interactions, alcohol withdrawal syndrome, and physical trauma. Other medical conditions associated with delirium include stroke, heart attack, brain tumour, or head injury.

Delirium can also occur suddenly without any warning signs or symptoms. This type of delirium is known as an acute confused state and can be caused by certain medications such as sedatives and hypnotics that are used to treat anxiety and insomnia. In addition to this, certain environmental factors such as extreme temperatures can also trigger the onset of delirium.

Diagnosis and Treatment for Delirium

Delirium is a serious medical condition that can be life-threatening if left untreated. It is characterized by an acute onset of confusion and disorientation, often accompanied by changes in behaviour, mood, and cognitive functioning. It is most common in elderly patients who have other underlying medical conditions or are taking certain medications.

Diagnosing delirium requires a thorough physical and mental health evaluation, including a detailed review of the patient’s history and current symptoms.

Treatment for delirium typically involves addressing any underlying medical issues as well as providing medications to help manage delusions and other psychiatric disorders. In some cases, supportive psychotherapy may also be recommended to help the patient cope with their symptoms.

Preventing and Managing Delirium

Preventing hospital-acquired delirium in patients over 65 is an important part of patient care. Healthcare providers should take steps to reduce the risk of delirium by assessing the patient’s risk factors, providing adequate hydration and nutrition, avoiding medications that may increase the risk of delirium, providing appropriate stimulation, and ensuring good sleep hygiene.

In addition to prevention strategies, healthcare providers should also be prepared to quickly recognize signs of delirium and provide appropriate treatment when needed. Early recognition and intervention are key for preventing long-term complications from hospital-acquired delirium in elderly patients.

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