• FAQ’s delirium

    How often does delirium occur?

    Marcantonio’s 2017 publication describes that approximately 33% of people over the age of 70 admitted to hospital get delirium. Delirium is the most common complication after surgery in elderly patients over 70 years of age where:

    • 15 to 25% of elderly patients develop delirium after major surgery
    • 50% of elderly patients develop delirium after high-risk surgery such as trauma surgery
    • in the intensive care delirium in 19% to 82% of patients, depending on the population (Source: Inouye, 2014, The Lancet)

    FAQ delirium

    Delirium is also called acute confusion or acute brain failure. This confusion develops in a short time (usually within a number of hours or days), can fluctuate in severity during the day and always has a physical cause (American Psychiatric Association – Diagnostic and Statistical Manual of Mental disorders, Fifth Edition, DSM-5). Delirium is diagnosed based on clinical characteristics. Research shows that only 12% to 35% of delirious patients are recognized with the current screening tools (source: Marcantonio, 2017, NEJM). 

    People with delirium usually don’t know they’re confused themselves. Delirium is very scary for patients and their family and sometimes make providing care in hospitals more challenging. The confusion usually decreases as the physical condition improves. The period of confusion varies from a few hours to weeks. Not all patients fully recover from delirium. Many patients keep residual symptoms, such as memory and concentration disorders, for a longer period of time.

    Acute encephalopathy is a rapidly developing (very regular in hours to several days) pathobiological process (disease/disturbance)in the brain. Acute encephalopathy is diagnosed using EEG (ElectroEncephaloGraphy)  (sources:  Slooter et al., 2020, Intensive Care Med.; Hut et al., 2021 Psychiatry Clin Neurosci.). In many cases acute encephalopathy manifests itself as delirium.

    Acute encephalopathy and delirium always have an underlying physical disorder. It can be caused by disease (infection), injury (such as a bone fracture after a fall), surgery or intoxication by a wrong combination of drugs.

    When one talks about delirium, one often talks about the hyperactive form; the acute confusion usually manifests itself in turmoil, such as patients pulling or picking sheets, wanting to get out of bed, pulling on infusion lines, changing consciousness, difficulty orienting, not being able to concentrate properly, forgetfulness and language disorders.

    However, patients with delirium may also present with the hypoactive (apathetic/silent) or mixed form (fluctuating between hyperactive and hypoactive episodes). So, delirium can manifest itself in different forms. Up to 75% of delirium patients have hypoactive or silent delirium. With the current screening tools, this group is often missed. Only 12% to 35% of delirium patients are recognized (source: Marcantonio, 2017, N Engl J Med). Hypoactive (silent) delirium is more difficult to recognize than the hyperactive delirium and can often be confused with dementia or depression. Because of this difficult recognition, hypoactive delirium is associated with poorer patient outcomes.

    It is still the case that most cases of delirium are not recognized. Only 12% to 35% of delirium patients are recognized where up to 75% of patients have a mixed,  hypoactive/silent form of delirium. These patients in particular are missed with current screening methods (Source: Marcantonio, 2017, NEJM)

    Anyone can get delirium. Older age, vulnerability (permeable blood-brain barrier) and dementia significantly increase the risk of delirium.

    Even a short (hypoactive or silent) delirium episode increases the risk of poor disease recovery, possible admission to a nursing home and increased risk of dementia and/or death.

    Delirium is stressful and can cause terrifying thoughts or hallucinations, for example having the idea of being trapped or seeing images that are not there. It can also cause anxiety and anxiety for family members and carers.

    The most important thing is to address the underlying disease(s) or causes as soon as possible. For example, to detect a disturbance in the electrolytes, to diagnose an emerging infection or sepsis, or to sanitize the medication that could trigger the delirium.

    Unfortunately, there is no drug for the treatment of delirium. Other measures that can be taken are:

    • The use of glasses and/or hearing aids;
    • Reassuring and helping to orient the patient, and avoiding conflicts;
    • Early mobilisation: helping the patient to get out of bed and get up;
    • Let the patient sleep peacefully at night;
    • Talk quietly and play games or puzzles together with the patient.

    Bron: iDelirium.org

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