Nov 25th 2022
Delirium is the acute onset and temporary disturbances to a person's consciousness, attention and awareness, often resulting in a debilitating state of sudden confusion. Symptoms can vary depending on the type of delirium and can worsen if appropriate treatment isn’t given.
Delirium (also called Acute Confusional State (ACS)) is a severe state of mental confusion and disorientation caused by a sudden change resulting in altered level of consciousness, cognition and perception, and inattention. In many cases, delirium causes a lack of awareness, so people may not understand that they have delirium. This can be distressing for the person experiencing an episode of delirium since it may cause anxiety related to disorientation and confusion.
Delirium is a syndrome comprised of several complex symptoms. Persistent delirium is typically misdiagnosed and mistreated as dementia, which is a separate cognitive disorder. They can share similar symptoms, but they are clinically very different.
Depending on the type of delirium, a person experiencing an episode can present with psychotic features such as hallucinations, physical signs of stress like pacing, and behavioral changes such as aggressiveness. Some severe cases of delirium will require emergency medical attention.
There are three clinical subtypes of delirium categorized according to psychomotor activity and cause.
The onset of delirium occurs suddenly, meaning that the changes in a person’s physical and mental status can develop over hours or a few days. The severity of symptoms may fluctuate throughout the day and worsen in the evening (termed sundowning). However, sundowning is a type of delirium that almost exclusively impacts individuals with dementia.
The following is a brief clinical description of the main delirium symptoms of hyperactive and hypoactive delirium and associated behaviors.
A person with delirium may misinterpret their environment or the actions of those attending to them. As a result, the person may act aggressively.
Delirium can cause a person to experience sensory impairments in cognition and cognitive processes.
A person with delirium can have significantly diminished awareness, attention and responsiveness to their environment.
Patients with delirium can display uncharacteristically extreme mood and emotional states – particularly in response to delusions or hallucinations.
In addition to these symptoms, people with delirium may also experience physical impairments such as dizziness, loss of coordination, falling down, and lightheadedness.
Doctors will conduct a preliminary evaluation of delirium from detailed historical medical records and informed observers (caregivers or family members). This procedure establishes a baseline of cognition and behaviors pre-onset.
Clinical assessments for the detection of delirium include mental and physical examinations. The Confusion Assessment Method (CAM) is a widely used delirium assessment tool.
The Confusion Assessment Method assessment has four criteria: (1) Acute Onset and Fluctuation Course, (2) Inattention, (3) Disorganized Thinking and (4) Altered Levels of Consciousness. This assessment tool has variations developed to distinguish delirium from other types of cognitive impairment.
CAM scores are measured as (0) absent, (1) mild, (2) marked, and anything higher suggesting severe delirium.
In addition, physical examinations in conjunction with assessment tools can be use to determine underlying causation. These can include checking blood pressure, heart rate, blood tests and urine tests.
Delirium is an acute syndrome that usually as an underlying cause. Conditions that significantly change a person’s brain function can trigger the condition's onset. These can include:
Given the right conditions and by identifying and removing the cause, delirium is reversible. Preventing delirium is possible by identifying risk factors in individuals with predisposing factors such as age or comorbidities and being aware of adding precipitating factors like certain psychoactive medications.
Minimizing the risk factors for delirium is vital in preventing it, not only for the individual but for carers, family members and healthcare professionals.
Critical factors that can increase the risk of delirium are:
When treating delirium, medical professionals will always aim to treat the underlying condition that is causing or linked to it first. For example, if someone is experiencing low blood pressure or lack of oxygen to the brain, these symptoms will be addressed before further treatment for delirium is given.
Doctors may also administer antibiotics if the delirium is stemming from an infection, as well as ceasing any nonessential medication that may be exacerbating the condition.
Once any underlying health conditions have been seen to, nursing staff will work to ensure the patient is comfortable and in a calming setting to ensure the delirium abates smoothly.
Common techniques used to calm those suffering from delirium are:
It is rare that delirium will be treated with direct medication in the first instance. However, certain symptoms such as psychosis may pose a threat to the individual or others and further treatment will require pharmacological intervention first.
Medications used to treat aggressive delirium symptoms include:
Individuals – together with carers and family members – can contribute to the improvement of their condition and its prevention moving forward. Awareness of the risk and susceptibility factors above can provide the basis for proactive self-care management of delirium.
It is a good idea for caregivers (family or friends) to discuss the person’s short- and long-term needs with a health care provider and develop a treatment plan. The goal of supportive care is to assist in maintaining good mental function and physical health, not aggravate delirium, and prevent additional complications.
Ways to accomplish this are very similar to those of self-care for delirium. Here are some things to do:
Although delirium is a complex psychiatric disorder, the prognosis for complete recovery is generally favourable. However, this is contingent upon immediate diagnosis, appropriate interventions, age, and the individual's past and current health conditions.
However, there are some factors that can impair a person's recovery from delirium even with intervention. Some people experience distressing memories of delirium that can cause anxiety and stress, while others with mental disorders such as dementia can find symptoms of their condition worsen after an incidence of delirium.
Delirium is a common symptom of a wide range of conditions in elderly patients aged 65 years and older. A 2018 study found that 14.7% of patients in UK hospitals over 65 years old had diagnosable delirium, with most being in the higher level of frailty on the Clinical Frailty Scale (CFS).
Delirium and dementia are two different conditions. The development of delirium is quick, from hours to days, and is reversible once the cause is determined and treated. Dementia develops more slowly, over months or even years, and is not reversible. Delirium is common in patients with dementia, but they are not the same condition.
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