Delirium, also commonly referred to as encephalopathy, altered mental status, or change in mental status, is an acute disorder of attention and cognition. The etiologies of delirium vary and may include infectious, chronic, or severe illnesses, medications, metabolic disturbances, and endocrine causes. Depending on the patient’s presentation, delirium is likely one of the biggest sources of consternation, or even panic, for psychiatric professionals and hospital staff members.

Although delirium is often recognizable, particularly if patients are presenting with prominent hyperactive-type symptoms such as agitation and psychosis, the condition remains underdiagnosed in general. Despite an incidence rate of up to 80% in hospitalized elderly patients, more than 60% of delirium cases are either missed or misdiagnosed.1 Delirium can worsen the outcome of patients’ comorbidities and carries a mortality rate as high as 40%.2 Therefore, being able to understand, recognize, and treat delirium is an important skillset for any mental health professional or clinician working in a hospital or long-term care setting.

Symptomatology of Delirium

Delirium is an acute disorder with an abrupt onset, typically within days or even hours. The condition is characterized by an altered level of consciousness, inability to focus, disorientation, both long- and short-term memory impairment, disorganized thinking, perceptual disturbances, and sleep-wake cycle imbalances.3,4

Delirium can be further categorized into hyperactive or hypoactive delirium. In patients with hyperactive delirium, clinicians may see more psychotic symptoms at the time of presentation, such as hallucinations and delusions. In addition, these patients may present with agitation, irritability, or combativeness. Patients presenting with hyperactive delirium with high levels of behavioral disturbances may be a large source of frustration for healthcare staff and even distress for the patients’ family members.

On the other hand, patients with hypoactive delirium are typically hypersomnolent and present with less psychomotor activities. The hidden danger with this category of patients is that their presentation may be hard to distinguish from other illnesses, such as depression and dementia. Since patients with hypoactive delirium tend to be less disruptive to hospital staff, their condition may be less recognizable and subsequently underdiagnosed, which may be detrimental and dangerous to a patient’s prognosis in the long term.

Assessing for Delirium

The first step in the assessment process of a patient suspected of having delirium would be to get a good history.

What kind of symptoms has the patient experienced that would make you consider delirium?

How long have those symptoms been around, and what has been the progression of those symptoms?

What are the patient’s recent medical and medication history?

For patients who may be unwilling or unable to provide their history, clinicians may want to consider gathering information from family members and caretakers, or if the patient is in the hospital, other hospital staff members including physicians, nurses, and nursing/medical assistants can provide helpful input.

The next step is to conduct a thorough examination of your patient, as well as a detailed medical workup (for hospitalized patients, these tests are often included in a “typical” workup). Laboratory tests that should be considered include:

  • CBC
  • BMP
  • LFT
  • TSH
  • urinalysis
  • blood/urine cultures

It may be advisable to check specifically for urinary retention and fecal impaction. Head/neck imaging studies should be considered as well, particularly if there is a sudden change in mental status, or if there are asymmetrical neurological signs.

In terms of assessment tools that are specific for delirium, the most utilized tool is the Confusion Assessment Method (CAM)5. This screening includes a list of questions for providers on the patient’s presentation, such as onset of symptoms, level of consciousness, and orientation. Other options include the clock draw test, mini-mental state exam (MMSE), the Montreal Cognitive Assessment (MoCA), and the digit span memory test. These screens are less sensitive and specific to delirium, since they are also used in the assessment of dementia, but may be appropriate for detecting any deviation from patient’s baseline mentation.

Clinical Management of Delirium

The first step in the management of delirium is to educate the patient, family members, and caregivers. Delirium is not a condition that is often talked about in the general public, so it can be scary for families to see their loved ones behave in ways that are bizarre and far from their baselines. It is important to explain some of the characteristics of delirium, especially the fact that it has a fluctuating course and that the resolution of delirium generally takes much longer than the onset. Most importantly, delirium, in the majority of cases, is completely reversible.

As for the treatment of delirium, it is important to recognize and treat the underlying cause, whether it is electrolyte abnormalities, infections, or medications. Regarding medications, there are specific categories of medications known to increase the risk for delirium – namely, anticholinergic medications and benzodiazepines. For elderly patients who may be taking pain medications, opioids can often lead to constipation, which may further induce delirium.

An often under-recognized but equally important aspect of delirium management is the re-orientation of the patient. This step is important to consider when the patient has sensory deficits that may preclude them from re-orienting themselves. If the patient wears corrective glasses or hearing aids, encourage them to retrieve and put them on.

It is also crucial to consider restraints such as side rails, restrictive furniture, as well as tethering such as Foley catheter, IV lines, and compression stockings.6 In addition, clinicians may consider collaborating with a physical/occupational therapist to develop a mobilization plan for the patient if deemed appropriate.

Together, these strategies should help guide delirium patients toward recovery.

Residents’ Corner: Tips from the Authoring Residents

“Delirium for me has always been a fascinating condition. While there are known risk factors that predispose certain patient populations to delirium, in many ways delirium can also be seen as the great equalizer. No matter the patient’s education level, or socioeconomic standing, delirium reduces everyone it touches to a shadow of their former selves. Delirium is demeaning, leaving patients undignified, rendering them a terror to spouses and family members, and unfortunately at times, a target of mockery for some. It is important to recognize and manage delirium – aside from the recovery of health, you are restoring the dignity and essence of a person.”

–Timothy Wong, DO

“I have found it difficult to obtain a thorough history in delirium patients. Getting collateral information to establish the patient’s mental baseline before hospitalization is crucial. Based on the timeline of symptom development, this can be especially helpful in ruling out dementias in an elderly patient. It is also helpful to contact the patient’s primary care provider for collaboration of care and to further learn about the patient’s medical history. Even if these patients are able to converse with you, the waxing and waning aspect of delirium make the overall history unreliable. I have found this approach to be very beneficial in this patient population”

­–Danielle Weitzer, DO

Last Updated: Jun 15, 2021