Delirium revisited

Delirium is a medical emergency. It is characterized by acute disturbance of consciousness, with changes in perceptual disturbances and fluctuation of symptoms. Delirium is often the initial manifestation of an underlying acute illness and can be present before fever, tachypnea, tachycardia, or hypoxia. There is an ED prevalence ranging from 7-24%, with increased mortality rates as high as 30.8% mortality at 6 months. There is an intricate relationship between pre-disposing factors and precipitating factors/insults that may lead to delirium, especially in older ED patients.

Subtypes

• Hypoactive delirium: Hypoactive delirium is described as “quiet” delirium and is characterized by decreased psychomotor activity. These patients can appear depressed, sedated, somnolent, or even lethargic. Prevalence ranges from 29-44%, and it is often the subtype most often missed by ED physicians and hospitalists.
• Hyperactive delirium: Patients with hyperactive delirium have increased psychomotor activity and they appear restless, anxious, agitated, and even combative. Prevalence ranges from 2-21%.
• Mixed delirium: Patients with mixed-type delirium exhibit fluctuating levels of psychomotor activity (hypoactive and hyperactive) over a period of time. Prevalence ranges from 43-55%.

We are under-diagnosing Delirium!

Studies have shown that delirium is often under-diagnosed in the Emergency Department, as well as low rates of documentation. A study by Kakuma (2000) found that in two Montreal Emergency Departments, there was a 9% prevalence of delirium, and that delirium was only documented in 9 out of 16 patients. They showed that in comparison to psychiatrists, ED physicians only recognized delirium in 35% of the patients. These results were replicated in another study where ED physicians only recognized delirium in 24% of patients. Delirium unrecognized by Emergency Physicians is likely to also be missed by hospital physicians at time of admission. They also found that a history of dementia, hearing impairment, and a Katz score less than or equal to 4 were independent risk factors for the development of delirium.

These findings are asynchronous with ED physician perspectives where 97% of ED physicians reported intermediate, advanced or expert familiar with the “detection and management” of delirium in the ED. Despite high mortality and morbidity in these populations, especially those discharged, 41% of ED physicians were neutral, not concerned or less concerned about discharging patients with delirium. This finding is concerning, given higher mortality rates among adults discharged from the ED with detected delirium and that unknowingly discharging a patient with delirium may be associated with higher mortality. Delirious patients may not comprehend their discharge instructions leading to non-compliance and potentially worse outcomes.

Challenges with Diagnosis Delirium

A British study interviewing physicians found that the ED environment, recognizing delirium in patients with dementia, and time constraints, were the biggest challenges.

1. The ED Environment

The department can be loud, with high patient turnover, multiple room and personnel changes. As quoted by a participant:

“The biggest challenge is the Department. You’ve got limited time and resources to dedicate to one patient at one moment in time. Period. You’ve got a static snapshot of a dynamic disease or process. The way that departments are across the country, ours no exception, is that will be the greatest challenge for any ED physician, right, is the actual physical department and the challenges based on patient flow and numbers.”

Increased ED hallway length of stay is also unsurprisingly associated with the development of delirium.

2. Delirium in Patients with Dementia

26-40% of older patients in the ED present with cognitive impairment. Most patients with dementia are previously undiagnosed. Recognizing acute fluctuations in cognition in patients with baseline cognitive dysfunction can be challenging, especially in a busy ED setting. As stated by a physician:

“The other negative line that I know that we’ve all had at some point is the nursing home resident who’s older and non-communicative,  who comes in for an “altered mental status” and then you don’t know what her baseline is, there’s very little in the documentation of what the change in mental status is, just “altered.” You know, you end up spending a fair amount of time trying to figure out even through the old records or calling the nursing home to figure out ok, what is it that’s changed today.”

Unlike delirium, dementia is characterized by a gradual decline in cognition occurring over months or years, and is usually irreversible. Altered level of consciousness, inattention, perceptual disturbances and disorganized thinking are not commonly observed in patients with dementia. Delirium in dementia patient can accelerate trajectory. This is why establishing their baseline mental status is crucial to diagnosing delirium in patients with severe dementia.

One of the few studies on delirium superimposed dementia (DSD) found that these patients have a higher short term mortality (25%), and increased length of stay in hospital (9 vs 5 days). At one month follow-up, subjects with delirium had greater functional decline. Many of the patients presented with potentially modifiable and preventable community or ambulatory care conditions or dehydration, falling, sensory impairment and dehydration.

In accordance to the NICE guidelines from the United Kingdom, if there is difficulty distinguishing the diagnosis of delirium, dementia, depression, or DSD; treat the delirium first. If considering discharge from the ED, a formal Geriatric EM consult should be requested.

Screening for Delirium

Based on ED data, low recognition rates, as well as qualitative information from ED physicians, there is a need for cognitive assessment and screening of patients in the ED. Multiple international geriatric societies have recommended cognitive screening for delirium in geriatric patients in the ED. However, there are many delirium screening tools, and they can be time consuming (ranging from 2 minutes to 30 minutes), have variable sensitivity and specificities, are resource intensive, and most are not validated in the ED. Frankly, most are not suitable for the high acuity and time demands of the ED.

The Delirium Triage Screen (DTS) and brief Confusion Assessment Method (bCAM) have been validated for use in the ED, and takes approximately 2 minutes to perform. The DTS is a highly sensitive tool (98% sensitivity, 55% specific) to help rule out patients who don’t have delirium. If a patient screens positive for DTS, the bCAM tool can be used to assess for delirium with 84% sensitivity and 94% specificity.

A frequent challenge, as stated earlier, is obtaining collateral information. In their validation study, feature 1 of altered mental status was primarily determined by surrogate interview in the ED or by phone. If the patient was from a nursing home, then the nursing home nurse was contacted. If the patient lived alone at home and no collateral history was available, then the medical record was reviewed to help determine the patient’s baseline mental status. If no information about the patient’s baseline mental status was available and the patient was feature 2 (inattention) positive and either feature 3 (altered level of consciousness) or 4 (disorganized thinking) positive, then it was assumed that the patient was feature 1 positive.

The ADEPT Tool

The Assessment, Diagnosis, Evaluation, Prevention and Treatment (ADEPT) tool was derived by consensus of experts to develop a framework to approach the undifferentiated confused and agitated elderly patient in the ED. This can also be used to approach a patient in whom we may be concerned about delirium.

Assess

It is important first to rule out life-threatening conditions first, including hypoxia, myocardial infection or sepsis. Perform a thorough history and physical exam to illicit any risk factors or potential precipitating factors for delirium. Rule out the common conditions of infection, neurological disorder, or electrolyte/metabolic abnormalities. Although the DIMES pneumonic is a useful starting point for the workup of delirium, there are over 100 precipitating factors for delirium.

Diagnose

It is imperative to establish baseline mental status for older ED patients. This can include family members, caretakers, or even friends. The DTS +/- bCAM can be used to screen for delirium. Advanced age, dementia and functional impairment has been frequently shown to be associated with delirium.

Evaluate

The best treatment for delirium is to treat its cause, and that requires a thorough investigation. Basic lab work including CBC, extended electrolytes and TSH is often used. Afebrile bacteria is a relatively uncommon phenomenon and is often associated with malignancy and in-dwelling catheters; therefore consider blood cultures in those patients if afebrile.

Urinalysis

There is a high incidence of asymptomatic bacteriuria in geriatric populations. The scientific link between confusion and UTI is equivocal, and there currently lacks any high quality evidence showing a causation between UTI and delirium. Treatment of asymptomatic bacteriuria risks premature closure bias, leading to misdiagnosis and treatment failure. Unwarranted antibiotic therapy predisposes patients to antibiotic resistance, side effects including C Diff, and worsening delirium. Urinalysis should be obtained in accordance to the LOEB criteria below, as supported by Choosing Wisely Canada.

• For older patients presenting with delirium without localized urinary symptoms or systemic signs of a serious infection, forgo routine ordering of urinalysis and urine culture.
• For older patients presenting with delirium and localized or
• systemic signs of infection, routine urine studies and antimicrobial therapy may be appropriate.
• For older patients presenting with delirium without localized symptoms or systemic signs of serious infection, attempt to first identify the cause of the change in mental status by obtaining history from a reliable informant, performing a thorough physical and neurologic examination, and evaluating for metabolic and electrolyte derangements.

CT Head

The utility of CT Head in ED patients with “altered level of consciousness” ranges from 4.6-13%. Choosing Wisely Canada currently recommends obtaining a CT Head if the patient has focal neurological deficits, head trauma/falls (especially if anti coagulated), GCS < 14, or signs of increased intracranial pressure.

Prevent

As stated earlier, most EDs are busy, bright, noisy and potentially deliriogenic environments. While the impact you may have may be minimal, a little goes a long way. Unfortunately, there is paucity in the evidence for ED prevention guidelines for delirium. The 4Ms Framework of an Age-Friendly Health System offers a framework to help mitigate worsening delirium.

• • Mentation: assess cognition; screen for dementia, delirium, or depression.
  • Mobility: assess mobility/fall risk, and encourage safe mobility.
  • what Matters: engage family, respect patient values (including advanced directives)
  • Mediations: re-order home medications, especially PRNs for pain or agitation.

Treat

While the goal in the ED is to identify the inciting cause of delirium, this approach can be broadened to also treat the common symptoms of delirium. These include:

• • Re-orientation: updating patients whiteboard, orienting to time/place
  • Fluid Repletion: unless NPO for surgical reasons, provide IV/PO fluid replacement and prevent/treat dehydration.
  • Mobilization: promote safe mobility rather than immobilize.
  • Vision and hearing aids
  • Sleep, pain and medications

Agitation in Delirium

Patients presenting with hyperactive or mixed delirium may be agitated, as this is often associated with perceptual disturbances. It is important to become experts in verbal de-escalation, as most patient agitation can be controlled with verbal de-escalation alone. Providers should respect personal space, establish verbal contact, be concise, lay down the law and set clear limits.

Physical restraints, while used in North America, should be ordered with caution. There is evidence from the Intensive Care Units that physical restraints increase the risk of delirium. Review the Canadian Geriatrics Society’s “Least Restraint, Last Resort” principles for cautious use of physical restraints only when needed, and only for as long as needed.

Benzodiazepines are contra-indicated for the management of delirium, unless the inciting factor is alcohol withdrawal or benzodiazepine withdrawal. There is a link to increased incidence of delirium with the use of benzodiazepines, especially at high doses (Diazepam 5mg equivalent).

Anti-psychotic have variable evidence on their use for agitation in delirium. While typical anti-psychotics such as Haldol have FDA warning recommending against the use in geriatric population, recent literature in the ICU has been less harmful. A Cochrane review by Rose and colleagues found that there is no data on antipsychotics on altering the duration of delirium, length of hospital stay, discharge disposition, or health-related quality of life. There is poor quality data showing that these agents did not reduce delirium severity. Furthermore, extra-pyramidal symptoms (EPS) were not more frequent with antipsychotics compared to non-antipsychotics, and no different for typical vs atypical anti-psychotics. The NICE guidelines recommend the use of low dose anti-psychotics and to titrate with caution. The table below summarizes some common agents and their doses as used at The Ottawa Hospital.

The Patient Experience

Delirium is a medical emergency that profoundly affects patients, families, and healthcare workers. Patients describe terrifying hallucinations, often perceiving healthcare workers as threats. These vivid experiences can leave emotional scars, causing long-term trauma, guilt, and a fear of seeking future care.

Families, too, experience distress, watching loved ones become unrecognizable and feeling powerless to help. The emotional toll is heavy, leaving them grappling with helplessness and guilt. Nurses, who often manage delirious patients, face ethical dilemmas when using restraints or sedation, torn between ensuring safety and offering compassionate care.

By recognizing the human side of delirium and responding with empathy and understanding, we can provide holistic, compassionate care that acknowledges the challenges faced by all involved. Delirium may be temporary, but its effects can last far beyond the hospital stay.

Summary

• Assess: Rule out life-threatening disease, detailed history and physical.
• Diagnose: Establish baseline mental status,  obtain collateral information, screen for delirium with DTS +/- bCAM, identify risk factors  (dementia, age, functional dependence).
• Evaluate: Perform bloodwork based on history and physical. Obtain urine analysis as per LOEB criteria (symptoms or fever). CT Head: Focal Neurological Deficit, Falls, GCS < 14.
• Prevent further worsening of delirium using the 4Ms (mentation, medication, what matters, and mobility)
• Treat the common things: pain, dehydration, constipation. Re-orient, encourage safe mobility, and engage family.
• Trial verbal de-escalation for agitation. Avoid benzodiazepines. Ensure physical restraints are necessary; and if using medications, start at lower doses and monitor.