Risk Factors

Risk factors for delirium are multifactorial and should be avoided or minimized when possible in the acute care setting.^1,6,7 Many acute care patients have more than 10 risk factors, increasing the chances of developing delirium.⁷ Risk factors can be preexisting or iatrogenic in nature. Preexisting risk factors include comorbidities such as advanced age, severity of illness, and reduced vision or hearing, with dementia being one of the strongest indicators of developing delirium.^1,2,8 Iatrogenic risk factors, such as circadian rhythm dysregulation, sedative medications, mechanical ventilation and immobilization, can increase delirium incidence or amplify preexisting conditions.^1,8,9 These are modifiable in most cases.

General Risk Factors

Risk factors can be easily remembered with the following acronyms:

Preexisting risk factors (SADS):

Severity of illness/Sepsis
Age/Alcohol
Dementia/Depression
Sensory impairment (hearing/vision)

Iatrogenic risk factors (MISS):

Mechanical ventilation
Immobilization
Sleep (circadian rhythm disruption)
Sedatives (benzodiazepines, muscle relaxants, anticholinergics)

Neurocognitive Impairment

Delirium incidence increases in patients with neurocognitive disorders, and delirium can be difficult to diagnose in these patients. As a result, they are often overlooked for delirium assessment.

In older patients with dementia, every point increase in dementia severity on the Global Deterioration Scale has been associated with a 50% increase in delirium risk.¹ These patients should be screened because delirium is a change from baseline and a separate entity from dementia. Delirium is acute brain dysfunction and a sign of an underlying process that must be addressed. Dementia lowers the threshold for delirium; it does not cause it. Patients with dementia are in dire need of systematic daily delirium assessments and delirium prevention strategies while hospitalized.

Frailty Scores

One risk factor for delirium that can be assessed with validated tools is frailty. Frailty has recently been associated with delirium, as these two clinical scenarios commonly affect older adults.¹⁰ Frail patients are often more medically complex, have a reduced tolerance for medical conditions and are less able to adapt to stressors than younger or non-frail adults. Increased vulnerability from frailty contributes to more adverse health outcomes, including falls, medical complications, disability, delirium and mortality.¹¹ Because frailty is associated with poor outcomes, it is important to assess for its presence in the older population.

A popular screening tool for frailty is the FRAIL scale. The mnemonic “FRAIL” is used to help clinicians remember the components:¹¹

• Fatigue: “Have you felt fatigued most or all of the time over the past month?”
  • Yes = 1, No = 0
• Resistance: “Do you have difficulty climbing a flight of stairs?”
  • Yes = 1, No = 0
• Ambulation: “Do you have difficulty walking one block?”
  • Yes = 1, No = 0
• Illnesses: “Do you have any of these illnesses: hypertension, diabetes, cancer (other than a minor skin cancer), chronic lung disease, heart attack, congestive heart failure, angina, asthma, arthritis, stroke and/or kidney disease?”
  • Five or more = 1, Fewer than five = 0
• Loss of weight: “Have you lost more than 5% of your weight in the past year?”
  • Yes = 1, No = 0
• Health status is represented in scores ranging from 3–5 as frail, 1–2 as pre-frail and 0 as robust.

Although cognitive and functional impairment along with advanced age are the strongest indicators of developing delirium, confusion should not be an expected part of aging. Confusion in a hospitalized patient regardless of age always requires further assessment.¹

Summary & Recommendations

• There are multiple known risk factors for delirium. However, all hospitalized patients are at risk.
• Understanding risk factors for delirium, such as SADS, MISS and frailty, are important but not necessary or sufficient for the development of delirium.
• Acute confusion in a hospitalized patient regardless of age, neurocognitive baseline or dementia always requires further assessment.

Classification, Identification and Screening

Delirium Classification

Delirium is heterogeneous and can vary by subtype. The most common subtyping classification system is based on psychomotor activity: hypoactive, hyperactive and mixed. In all of these subtypes, sleep/wake cycle disturbances are common, as are hallucinations, mood lability, and delusional or fixed false beliefs. Often, symptoms of delirium are worse in the evenings and at night.² Frequent fluctuations between hypoactive and hyperactive states can make the diagnosis difficult to confirm.

Hypoactive delirium, also known as quiet delirium, is characterized by slower motor movements, decreased alertness, decreased speech and overall decreased activity.^2,7 Hypoactive delirium is often mistaken as depression because patients with this subtype are withdrawn and may refuse food, physical therapy or medications.¹ Hypoactive delirium is missed in more than half of patients and associated with increased length of stay, worse quality of life and greater mortality.^1,2

The hyperactive delirium state is what most people associate with the definition of delirium. Patients in this state are restless and demonstrate prominent agitated motor behaviors, such as pulling out lines and striking out at staff.² It is rare that a patient has a pure hyperactive subtype.^2,13

Mixed motor delirium occurs as often as hypoactive delirium and is characterized by periods of both hypoactivity and hyperactivity within a matter of minutes to hours.^2,13 True classification of mixed motor delirium can be determined when there is evidence of both subtypes in the previous 24-hour period.¹²

Identification and Screening

Screening tools can be used for early intervention in the event delirium is identified. Since hypoactive delirium is often missed and leads to a worse prognosis than hyperactive delirium, it is imperative to adopt standard delirium monitoring processes.^1,14 Without active monitoring, delirium goes undiagnosed in 72% of cases.⁸ Patients with delirium have a mortality risk as high as 10%. Early and accurate recognition of delirium is crucial to the care of these patients and for early identification of the underlying etiology.

Delirium as a Vital Sign

Delirium screening tools facilitate an objective way for healthcare clinicians to communicate about delirium and acute confusion in their patients. The presence of delirium typically represents an acute underlying precipitating process, similar to how a fever represents an underlying infection or inflammatory process. Delirium, or acute brain dysfunction, can represent very serious underlying medical issues that, if not addressed in a timely manner, can lead to worse patient outcomes. There are several delirium monitoring assessment tools available. Those listed below have been well validated. Some are used across dozens of hospitals and have been translated into more than 30 languages.

Acute Care or Medical-Surgical Floor Unit: The Brief Confusion Assessment Method (bCAM)

The bCAM (Algorithm 1) is adapted from CAM-ICU (Algorithm 2) and is used to assess delirium in patients who are not mechanically ventilated and can communicate verbally.¹³ This assessment is more sensitive and specific for delirium given the verbal components than the CAM-ICU and is thus the recommended screening tool for all verbal hospitalized patients. Performing the exam can usually be done in less than one minute, especially if a family member or caregiver who knows the patient well is present.¹³ The bCAM is based on the following four criteria:^13,14

1. Acute onset [of confusion] or fluctuating mental status
2. Inattention
3. Altered level of consciousness
4. Disorganized thinking
5. The exam is considered positive when features one and two AND either three or four are present.^13,14

Feature one is assessed by the bedside provider or nurse for any acute confusion, change in mental status from baseline or fluctuation in mental status. This can include use of sedation or a change in baseline mental status reported by family.

Feature two has the patient state the months backward from December to July. If the patient is unable or refuses to perform this task, he or she should be considered feature-two positive.

Feature three is the Richmond Agitation Sedation Scale (RASS) (See Table 1).⁵⁸ Patients with RASS scores of -4 or -5 are considered comatose, and delirium is not able to be assessed (these are typically patients in the ICU). Individuals with RASS ≥-3 qualify for delirium assessment. If the patient has a RASS other than 0, they are considered to have delirium if feature one and two are also present.

Feature four (see Algorithm 1) addresses higher-order thinking and processing with two cognitive assessment questions and two motor command assessment questions. Any errors in feature four are considered a positive screen for delirium if feature one and two are also present.^13,14

It is important to complete all components of the bCAM assessment to ensure the highest sensitivity and specificity for delirium. The complete assessment takes on average less than one minute to complete.

An alternative to the bCAM is the 4AT method. This method has been validated in more than 3,500 patients with a sensitivity and specificity of 88%. It also takes fewer than two minutes and does not require any formal training.¹⁵

The 4AT consists of four components:

1. Alertness
2. AMT4 (age, date of birth, place, current year)
3. Attention
4. Acute change or fluctuating course

The 4AT method with scoring sheet is available for free at www.the4at.com.

Monitoring for delirium in non-ICU settings is key for the early identification and management of delirium. Vanderbilt Health Affiliated Network recommends evaluating at least once per shift (twice per 24 hours), including reassessment with any change of mental status. This frequency should be increased to three times per shift for patients in the ICU.

Acute Care/Med-Surg Floor, Step-down or ICU Setting: The Confusion Assessment Method-ICU (CAM-ICU)

The CAM-ICU is one of the most valid and reliable delirium screening methods used for adult ICU patients and can be used for patients who are ventilated or non-ventilated.^2,9,13,14 This tool takes less than one minute 90% of the time. It is based on the same four diagnostic criteria as the bCAM:^13,14

1. Acute onset [of confusion] or fluctuating mental status
2. Inattention
3. Altered level of consciousness
4. Disorganized thinking

Similar to the bCAM, the exam is considered positive when features one and two AND either three or four are present.^13,14

• FEATURE ONE: Same as bCAM
• FEATURE TWO: Assessed with a simple screen in which the evaluator states a series of letters— SAVEAHAART or CASABLANCA—and the patient is instructed to squeeze the evaluator’s hand only on hearing the letter A. Feature two is present if:
  • The patient has more than two errors—either squeezing on non-A letters or not squeezing on A.
  • The patient is unable or refuses to perform this task.
• FEATURE THREE: same as bCAM, RASS assessment
• FEATURE FOUR: same as bCAM
  • For the initial yes/no questions, the patient is asked four questions that assess thinking and two command questions that require higher-order processing.
  • If they have more than one error in feature four, they are considered CAM-ICU positive (see Algorithm 2).

Emergency Department (ED) or Busy Clinic Setting: Delirium Triage Screen (DTS)

Depending on the clinical environment, performing a one- to two-minute delirium assessment may not be feasible for all patients. One approach to streamline the delirium screening process is to perform a very brief (<20 seconds) delirium screen to rapidly rule out delirium and perform a confirmatory assessment only to rule in delirium in those who are positive. The DTS (Algorithm 3) is an example of an ultra-brief delirium screen. It was originally developed for use in the ED but can be used for inpatients as well. In older ED patients, the DTS is 98% sensitive and 55% specific for delirium.⁵

The DTS has only two components:

(1) Altered level of consciousness assessed by using an arousal tool (see bCAM Feature Three)

(2) Inattention, which is assessed by asking the patient to spell “LUNCH” backward

The DTS is considered negative if the patient has a normal level of consciousness and makes zero or one error when spelling “LUNCH” backward. If the patient has an altered level of consciousness or makes two or more errors during the spelling test, the exam is considered positive and a more specific test (bCAM or CAM-ICU; see below) is needed to confirm a delirium diagnosis.⁵ Delirium screenings are now being performed in EDs across the country, and this care path recommends instituting delirium screening in the ED setting to identify patients for delirium as soon as they arrive to the hospital for early intervention.

Instructions for Using the DTS

The DTS was developed to rapidly rule out delirium and reduce the need for formal delirium assessments. It takes fewer than 20 seconds to perform and consists of two components:

1. Level of consciousness as measured by the RASS
2. Inattention by spelling the word “LUNCH” backward
3. If the patient has a RASS of 0 (normal level of consciousness) or makes zero or one error on the “LUNCH” backward spelling test, the DTS is considered negative. Because the DTS is 98% sensitive, delirium is ruled out in this case, and no additional delirium testing is needed. If the patient has a RASS other than 0 (altered level of consciousness) or makes more than one error on the “LUNCH” spelling test, the DTS is considered positive. Because the DTS is 55% specific, confirmatory testing is needed using the bCAM or CAM-ICU to rule in delirium.

Challenges and Limitations in Delirium Monitoring

Delirium Screening in Non-Verbal Patients

Identifying delirium can prove difficult since some patients may be non-verbal. Both the CAM-ICU and the Intensive Care Delirium Screening Checklist (ICDSC) were devised to address the non-verbal population, primarily in the ICU.^9,17 The CAM-ICU Feature Two (inattention) allows for a non-verbal patient to squeeze the clinician’s hand to elicit a response to questions. The ICDSC is an eight-question checklist that allows delirium symptoms to be observed over an eight- to 12-hour period¹⁷ and does not require the patient to be verbal. Vanderbilt Health Affiliated Network recommends the use of the CAM-ICU for non-verbal patients, given its close relationship to the bCAM.

Delirium Screening in Primary Neurologic Injury

Delirium has been shown to be highly prevalent in traumatic brain injury (TBI) and stroke populations.¹⁸ There are added complexities to identifying delirium in this patient population, especially when language processing centers of the brain have been affected. It is important to distinguish whether changes are related to primary structural injury or a secondary injury, such as delirium.¹⁴ Both the CAM-ICU and the ICDSC have been shown to have good sensitivity and specificity in this population.^9,17 Despite limitations for some patients, especially those with receptive aphasia, Vanderbilt Health Affiliated Network recommends delirium monitoring for neurocritically ill patients.

Delirium Screening in Patients With Preexisting Neurocognitive Disorders

Many delirium assessments rely on the assumption that the patient’s baseline neurocognitive status and ability to interact is intact. For patients with severe neurocognitive disorders or elements such as receptive aphasia, severe catatonia and extreme depression with flat affect, this can be more complicated to assess. However, it is still possible and should be attempted.^9,19

Summary & Recommendations

• Vanderbilt Health Affiliated Network recommends delirium screening for all patients admitted to the hospital, as anyone is at risk of developing delirium.
• Most delirium is hypoactive, which is also the most dangerous. Clinical judgment is not reliable for delirium assessment, and validated tools are required.
• For quick screens in the ED environment, the DTS can be performed. However, if DTS is positive, it must be confirmed with a bCAM or CAM-ICU.
• Screening with the bCAM in verbal patients (most sensitive/specific) is recommended at least once per nursing shift (every 12 hours), or in any scenario in which a patient’s mental status changes from baseline.
  • We recommend completing all four features during the assessment for the best sensitivity and specificity. This assessment takes one to two minutes to complete once familiar.
• Screening with the CAM-ICU should be performed at least once per shift in non-verbal floor patients, and at least three times per shift in the ICU or in any scenario in which a patient’s mental status changes from baseline.
  • We recommend completing all four features during the assessment for the best sensitivity and specificity. This assessment takes one to two minutes to complete once familiar.
• Delirium screening in patients with neurocognitive disorders or primary neurologic injury (TBI, stroke) can be more complicated. For those with verbal limitations, the CAM-ICU is recommended.
• Understanding a patient’s normal baseline is crucial to the appropriate evaluation of delirium.

Treatment Algorithms/Pharmacotherapy Standards

There is no current recommended pharmacologic treatment for delirium. Management of delirium relies on identifying and treating the underlying etiology at the root of the patient’s acute brain dysfunction. Early identification and attention to the source of delirium is key to mitigating the risk delirium poses for increased mortality, hospital length of stay and long-term cognitive impairment. Memory tool acronyms have been developed to guide clinicians in thinking through possible reversible or treatable causes of delirium. One of these acronyms is Stop THINK, which is described below.

Stop THINK

Stop THINK is an easy acronym that can be implemented in a collaborative way among clinicians, nurses and physical therapists to consider possible reversible causes, triggers or precipitating factors for delirium. The acronym is outlined in Table 2.

Pharmacology Considerations

Many medications can contribute to or precipitate delirium. We have listed the most common medication classes with specific examples in Table 3a. The goal as mentioned in the Stop THINK table is to stop these offending medications as soon as possible or try alternatives that are less associated with delirium.

There are currently no recommended pharmacologic treatments for delirium. Recent randomized control trials have demonstrated no benefit of either typical or atypical antipsychotics for delirium.²⁰ Antipsychotics remain viable for the short-term control of agitation, severe psychotic symptoms (e.g., hallucinations or delusions) or severe anxiety with the need to avoid respiratory suppression (e.g., heart failure, COPD or asthma). If an antipsychotic is initiated, low starting doses should be considered, and daily review of drug interactions, adverse effects, dosing titration and need for the antipsychotic should be completed.

If acute agitation places a patient or staff’s safety at risk, consider these classes of drugs (see Table 3b):

• FIRST LINE: Atypical antipsychotics (olanzapine ODT, quetiapine, ziprasidone) starting at the lowest possible dose for a clinical effect
  • Olanzapine: Start at 2.5mg q6h prn and up-titrate if needed.
  • Quetiapine: Start at 25mg or 12.5mg in older adults, q6h prn and up-titrate as needed.
• SECOND LINE: Typical antipsychotics if patient is acutely agitated and a danger to themselves or others, and/or unable to take oral medications
  • A one-time dose of IV or IM haloperidol: start at 1mg for adults and 0.5mg if older than 65
  • May repeat or double dose until resolution of acute agitation
• Consider an EKG to assess QTc and cardiac monitoring if repetitive dosing or other electrolyte abnormalities. If no recent electrolyte labs, obtain these and replace for K >4mEq/L and Mg >2mg/dL.
• Perform daily reassessment of the need for antipsychotics. This is also true for restraint orders.

NOT RECOMMENDED:

• Benzodiazepines have been shown to worsen delirium. These medications are indicated only in specific cases (see Table 3a).
• Statins,²¹ unless otherwise strongly medically indicated for cardiovascular indications

ICU Patients: Dexmedetomidine

We suggest using dexmedetomidine for delirium in mechanically ventilated adults where agitation is precluding weaning/extubation (conditional recommendation, low quality of evidence).²¹

Summary & Recommendations:

• Many underlying medical conditions can precipitate delirium. Stop THINK is a helpful acronym for differential diagnosis.
• There is no current pharmacologic treatment for delirium.
  • Acute agitation that places the patient or staff at risk may be treated with antipsychotics at the lowest possible dose for lowest possible duration.
  • Long-term antipsychotic therapy should be avoided.
  • Antipsychotic and restraint orders should be re-evaluated daily.
  • Patients should not be discharged on antipsychotic therapy initiated for in-hospital delirium.
• Benzodiazepines, anticholinergics and muscle relaxants carry the highest risks for delirium.
  • Initiation of any of these agents in hospitalized patients should be avoided in delirious patients unless absolutely medically indicated.
  • Minimizing use of these medications may help prevent development of delirium in high-risk individuals.

Delirium Prevention

Although screening and identifying delirium and addressing the underlying causes is of great importance, the best approach for decreasing delirium in our patients is to take steps to prevent it. Prevention of delirium can decrease healthcare costs and length of stay, improve outcomes, and decrease mortality.²³ Many studies have determined that delirium has iatrogenic components, which can be modified to decrease the chance of development.^1,9 It is estimated that more than a third of delirium cases in inpatient settings are preventable, and approaches that target modifiable risk factors have effectively prevented delirium in older hospitalized patients.^1,6

The Hospital Elder Life Program (HELP)

Advanced age is one of the strongest predictors for developing delirium,¹ and preventive measures for older adults should be implemented during hospitalization. HELP was developed to improve care and decrease delirium in hospitalized elderly patients²⁴ and includes multicomponent interventional strategies to do so.

The program has four main goals:²⁴

• Maintain cognitive and physical functioning of high-risk older adults throughout hospitalization.
• Maximize independence at discharge.
• Assist with the transition from hospital to home.
• Prevent unplanned hospital readmissions.

HELP is implemented by skilled geriatric volunteers or nursing staff (e.g., elder life specialists and elder life nurse specialists) who assess and enroll patients meeting specific criteria and determine interventions based on individual needs.²⁵ Patients enrolled in the program have regular reassessments for changing needs.

Depending on patients’ needs, HELP services can provide and coordinate the following interventions:²⁵

• Daily visitor program: cognitive orientation, communication and social support
• Therapeutic activities program: implementation of cognitive stimulation and socialization
• Early mobilization program: daily exercise and walking assistance
• Non-pharmacologic sleep protocol: promotes relaxation and sufficient sleep
• Hearing and vision protocol: hearing and vision adaptations and equipment
• Oral volume repletion and feeding assistance program: assistance and companionship during meals
• Geriatric interdisciplinary care: nursing, medicine, therapy, pharmacy, nutrition and chaplaincy services and support for patients and their families
• Provider education program: geriatric education for professional staff

In addition, the program connects patients and families to community services that assist with the transition from hospital to home.

Age-Friendly Health System

The Age-Friendly Health System, an initiative of the John A. Hartford Foundation, seeks to prevent harm, improve health outcomes and lower overall healthcare costs for older adults.²⁶

Four core features form the basis of age-friendly care and provide clinicians with interventions and action steps when caring for older adults.²⁷ The 4Ms address the gap between evidence-based best practices for older adults and the care they receive in current health systems.²⁷ The 4Ms include:^26,27

1. What matters: Know and act on each patient’s specific health outcome goals and care preferences including (but not limited to) end-of-life care.
2. Mobility: Maintain mobility and function and prevent/treat complications of immobility.
3. Mentation: Focus on delirium, dementia and depression across care settings.
4. Medication: Optimize use to reduce harm and burden, focusing on medications that affect mobility, mentation and what matters. If medication is necessary, use age-friendly medications.

ICU Patients

The ABCDEF Bundle

One of the most well-known strategies for preventing delirium in critically ill patients is implementing the ABCDEF (A2F) bundle. This bundle has been translated into over 30 languages and implemented in ICUs all over the world with significant improvement in delirium identification and decrease in duration.

The bundle consists of:

• A—Assess, prevent and manage pain
• B—Both spontaneous awakening and spontaneous breathing trials
• C—Choice of analgesic and sedation
• D—Delirium assessment, prevention and management
• E—Early mobility and exercise
• F—Family engagement and empowerment

Bundling these practices works to improve patient outcomes better than implementing each of these elements separately.⁹ The proper institution of these practices can reduce delirium the following day up to 40% and lead to an almost a 70% decreased risk of death during a patient’s ICU stay.^28,59,6,9 However, when first instituting the A2F bundle, it is important to do so in a stepwise fashion. Many institutions have had difficulty attempting simultaneous bundle initiation, and the creators recommend stepwise implementation of each separate component.

Compliance is important to reducing poor outcomes in the critical care setting. A2F bundle-associated improvements in patient mortality are directly correlated with bundle compliance.⁶

The A2F bundle is relevant for critically ill patients and addresses many aspects important to ICU liberation, such as sedation, and mechanical ventilation liberation, with delirium as just one component of this complex strategy. This care path is designed to address delirium in all patients hospital wide, not just ICU patients. For more information on ICU-specific delirium, we recommend using the resources available at
www.icudelirium.org.

Summary & Recommendations

Delirium prevention and early identification of risk factors are key for the appropriate assessment, diagnosis and management of delirium. Many multicomponent prevention strategies exist, and we have summarized strategies that can be used for all acute care patients (HOMEEES), as well as strategies specific to older patients (HELP and 4M) and ICU patients (A2F bundle). Overall, delirium prevention can be possible with a completely non-pharmacologic approach focusing on the areas of:

• Adequate nutrition/hydration and recognition of urinary retention or constipation
• Frequent reorientation with family/familiar face engagement and sensory restoration with hearing aids or glasses
• Minimizing medical devices and sleep interruptions
• Pharmacologic/Medical Prevention of Delirium
  • This is summarized in Section IV, with specific recommendations for medications to avoid and possible alternatives. Additionally, medical issues that may be underlying delirium are listed and should be addressed as soon as possible in all patients.

Patient and Family Education

Family engagement is an important component of managing delirium. When family members are involved, their wishes, concerns and participation complete any and all medical treatment plans, especially when patients cannot speak for themselves. Families have an increased sense of inclusion and respect and a better understanding of their loved one’s care.²⁹

General Guidance For Caregiver Engagement

Families or caregivers, if available, should be actively included in care decisions and clinical changes from admission to discharge. Families should be empowered to participate in delirium prevention with interventions, reorientation, interaction and, if safe and appropriate, assistance with mobility:³⁰

• Include caregivers as essential members of the healthcare team. Encourage them to ask questions, participate actively in rounds and shift changes, and share in decision-making.
• Communicate with caregivers clearly and regularly. Use whiteboards and other means to share the patient’s daily care plan and goals. Provide a daily schedule so caregivers can plan their day. Whenever you enter the room, explain what you are doing and why.
• Encourage caregivers to take care of themselves. Remind them to take breaks, eat regularly and get enough sleep. Assist them in locating any resources they may need.
• Educate caregivers. Intentionally engage caregivers in all patient education. Explain delirium signs and symptoms to watch for and what to do if they occur. Review the patient’s medications, as well as dosages and common side effects. Review diet and activity restrictions. Make sure the caregivers know whom to call if there are problems and when and where follow-up visits are scheduled. Confirm that caregivers have the resources they will need to care for the patient after discharge. Don’t do discharge teaching if a caregiver isn’t present.

Family/Caregiver Participation in Delirium Recognition and Prevention

Caregivers can be an invaluable resource in the prevention, management and recognition of delirium. While their loved one is in the hospital, they should receive education on not only how delirium can be recognized, but also how it can be prevented or managed if it develops.

For example, caregivers can be instrumental in:

• Recognizing confusion or change from baseline mental status
• Reorientation
• Social/cognitive engagement
• Assistance with meals or hydration
• Bringing attention to sensory restoration, such as the need for hearing aids/glasses
• Engaging mobility if deemed safe by the medical/nursing staff
• Bridging communication between clinicians and the patient, especially in the setting of memory complaints or baseline dementia

Engaging caregivers as active participants of the healthcare team in the management of patients with or at risk for delirium not only improves communication, education and patient care, but it also gives caregivers a strong voice and empowers them to address concerns or changes with their loved ones that may otherwise go unnoticed by those not as familiar with them. This will also facilitate the transition from hospital to home and prepare caregivers for delirium prevention and recognition after discharge.

Discharge Education

Education about delirium for patients and, in many cases, families/caregivers is critical at discharge given the long-term impact of delirium on cognitive impairment and activities of daily living.^8,31

Comprehensive discharge education about delirium is helpful for both caregivers and patients. With proper education, caregivers are able to recognize delirium symptoms and may be less fearful when an acute episode occurs. Caregivers are also most likely to pick up on subtle changes in cognition that would allow a patient to receive prompt treatment.³² After discharge, caregivers can use many of the in-hospital tools stated above, specifically:

• Recognition of confusion or change from baseline mental status
• Reorientation
• Social/cognitive engagement
• Assistance with meals or hydration
• Engagement in safe mobility (must be instructed prior to discharge)

Patients typically are not discharged if actively showing signs of delirium. However, some patients may develop delirium again after they leave the hospital, and caregivers should be made aware of warning signs, such as acute confusion or change in mental status, which should lead to a conversation with the patient’s clinician or a return visit for evaluation. Patients with dementia, especially those who experienced delirium, may suffer additional cognitive decline after a period of hospitalization, and caregivers should be counseled regarding a possible new baseline. However, any acute confusion from a patient’s baseline, even if that is a new baseline, should be addressed as soon as possible by a medical provider.

Many of these elements are published in printable, easily accessible resources for caregivers and can be accessed via the Krames StayWell Patient Education group. Other resources may be available through your hospital’s existing electronic medical record and at www.icudelirium.org.

Delirium is associated with long-term adverse outcomes after discharge, including continued cognitive impairment, institutional placement and difficulty performing activities of daily living.^8,31 Thorough instructions at discharge should be provided to family members or caregivers so they will be aware of what to expect or what to discuss with their loved one’s primary medical provider after a hospitalization.

The Food and Drug Administration has not approved any medications for delirium.¹ Although some patients may have required antipsychotics for acute agitation during hospitalization, clinicians should ensure that no antipsychotics or other psychotropic medications started during the hospital stay be prescribed or included in the discharge plan. A thorough medication reconciliation should be performed with the primary caregiver or care facility prior to discharge to ensure no deliriogenic medications are prescribed by physicians or administered at home. Please review Section IV for recommendations of pharmacologic management of delirium (Tables 2a and 2b).

It is essential to have a solid infrastructure in place for post-hospital delirium follow-up. Caregivers should be counseled that many outpatient clinicians are not familiar with the long-term impact of delirium and that caregivers should directly communicate with the follow-up provider that the patient suffered delirium while hospitalized. Although there are some special clinics and support groups that are forming for patients who have suffered delirium, these are not common. Caregivers should be educated about risks of cognitive impairment, mental illness and functional disability for patients who have suffered delirium, in order to address these topics with primary care clinicians if they do arise. The specific recommendations for outpatient clinicians is outlined in the next section (Table 3).

Summary & Recommendations

• Caregivers are an invaluable resource for delirium recognition, management and prevention.
• Caregivers should engage in assisting with all non-pharmacologic interventions as medically appropriate.
• Caregivers should be provided delirium-specific education prior to a loved one’s discharge.
• Caregivers should be provided with specific areas to address at post-hospital follow-up with their loved one’s primary care clinician, including assessments for cognitive impairment, mental health issues and functional disability.

Special Considerations and Follow-Up

Post-Hospital Impact of Delirium

Patients who have had delirium while hospitalized are prone to several cognitive and functional impairments after hospital discharge. This is especially impactful if they developed delirium while in the ICU.^33,34 It is critical that clinicians communicate what to expect to their family members prior to and at hospital discharge. Many patients hospitalized with delirium will have increased difficulties living independently after discharge. We recommend a multidisciplinary and comprehensive approach to these complex patients. For primary care clinicians treating patients who have been hospitalized with delirium, we recommend screening in three specific categories: cognitive impairment, mental health disorders, and functional or physical impairment.

Cognitive Impairment

In addition to the most severe risk of mortality, delirium is associated with poor cognitive outcomes after hospital discharge,^35,36,37 leading to a decreased quality of life for survivors. Delirium can accelerate cognitive decline and overall loss of functional independence. Loss of functional independence can cause aspiration events, poor oral intake and reduced mobility, leading to more serious complications (e.g., pulmonary embolism and skin breakdown).³⁸ These complications can be major contributing factors to hospital readmission or mortality. The duration of delirium is significantly correlated with worse scores on activities of daily living, impaired motor sensory function, and memory and naming impairments.³⁵ Impairments in cognitive function can persist beyond the first year of discharge.³⁹

Acute hospitalization for illness is not typically the ideal time to evaluate cognition. However, given that patients with underlying neurocognitive impairment are more likely to develop delirium, those who develop delirium can develop new long-term cognitive impairment. We recommend cognitive screening at post-hospital follow-up.

There are several tools that can be used quickly for cognitive assessment by post-hospital clinicians, such as primary care physicians. Two screening tools for patients with known dementia who are being assessed for a new baseline after having in-hospital delirium are AD8: The Washington Dementia Screening Test, also known as the Eight Item Interview to Differentiate Aging and Dementia,⁴⁰ and the Montreal Cognitive Assessment (MoCA).⁴¹

The AD8 was developed for the purpose of distinguishing between signs of normal aging and dementia. The screening tool can be directed toward either the patient or an informant (e.g., spouse, adult child or friend) and has been validated for use in the ED and other settings.⁴⁰

The MoCA cognitive screening is 90% sensitive in detecting mild cognitive impairment. To ensure consistency and accuracy of the results, exam administrators (e.g., clinicians, nurses, therapists, etc.) must be trained and certified.⁴¹

For patients without preexisting dementia, the MoCA can still be used to identify potential new cognitive impairment after in-hospital delirium. If abnormal, this should be followed up with a formal referral for neuropsychologic testing.

Mental Health

Delirium, as well as experiencing an ICU stay, can reduce quality of life and lead to other psychological impairments after discharge.⁴² Mechanical ventilation, sedation and hospital length of stay have all been identified as factors for developing post-discharge delirium and post-ICU psychological disorders. The incidence of developing anxiety or depression after an ICU stay is between 18% and 41% and post-traumatic stress disorder (PTSD) between 1.9% and 31.6%. Patients who had a diagnosis of PTSD or depression prior to admission to the ICU have a higher incidence of ICU-related depression and/or PTSD.^{43,62,63,64,65,66}

The incidence of psychological disorders is highest at three months post-discharge with some patients having a delayed onset of symptoms.⁴³ It is imperative that clinicians routinely perform assessments and follow-up of these patients to detect and treat any psychological disorders that may have resulted from hospitalization.

Some simple screening forms listed by the American Academy of Family Physicians that should be considered at post-hospital follow-up for patients who experienced delirium include:

• Depression: PHQ-9/PROMIS-10⁴⁴
• Anxiety: GAD-7⁴⁴
• PTSD: PC-PTSD⁴⁵
• Substance Use: DAST/AUDIT⁴⁶

Other validated screening tools for depression, anxiety, PTSD and substance use would be acceptable based on the practice setting and available tools. We stress the importance of screening for these elements in patients who experienced delirium.

Physical or Functional Impairment

Many patients who have developed delirium while hospitalized, especially those hospitalized in the ICU, deal with new, life-altering physical and/or functional impairments. Proper evaluation for new functional impairment, even in younger patients, is critical to the appropriate management of patients’ post-hospital delirium. Screening tools such as the Katz Index of Independence in Activities of Daily Living, the Lawton Instrumental Activities of Daily Living Scale (self-rated)^60,61 or any other validated tool for the assessment of functional impairment would be appropriate.

If functional impairment or concerns for the patient safely living independently are identified, prompt involvement of social work and family is important.

Summary & Recommendations

• All patients who have suffered delirium in the hospital should be considered at risk for cognitive impairment, mental health issues and functional impairment even over a year after hospital discharge.
• Outpatient follow-up clinicians should screen patients for these conditions at a three- to 12-month window post-discharge if it is known they had delirium while admitted.
• Many patients may have difficulty returning to work after suffering in-hospital delirium, and all efforts should be made to address their needs with the assistance of social work and case management.

Measurements and Outcomes

When instituting a new delirium monitoring program, it is important to monitor its utilization and compliance to ensure the best possible care for patients with delirium.

How Do we Measure Success of a New Delirium Monitoring Program?

Including delirium and mobility assessments as part of the medical record to be charted by nursing staff provides Vanderbilt Health Affiliated Network with granular data about the prevalence of delirium and may reveal previously unidentified risk factors or practice patterns that place patients at higher risk. Compliance with delirium assessment delivery and charting is key to the success of a delirium monitoring program. Achieving compliance will take many iterative steps of training, reinforcement and leadership of a small group of delirium monitoring “champions” who are willing and invested in teaching their colleagues how to perform these very quick and simple assessments. Without total investment from all levels of the enterprise, instituting a delirium monitoring program will not succeed.

Delirium not only causes poor clinical outcomes for patients affected by the condition, but it also contributes to unsatisfactory institutional and financial outcomes. Patients with delirium spend more time in the hospital, increasing length of stay and overall cost.^47,48 Other undesirable outcomes that increase with delirium include 30-day mortality⁴⁹ and hospital readmission rates,³⁸ falls,⁵⁰ and restraint days.⁵¹

Hospital Length of Stay

Delirium has been shown to be the strongest predictor of increased hospital stay, even when accounting for severity of illness, age, gender, race and days of benzodiazepine and narcotic administration.⁴ Patients who develop delirium while in the ICU have a 29% greater risk of staying in the ICU longer than expected and a 41% risk of staying in the hospital overall.⁵² Compared with patients without delirium, delirium patients spend a median of 10 days longer in the hospital.³⁶ Delirium in older ED patients has been found to be an independent predictor for increased length of stay.⁵³

ICU Length of Stay

The incidence of delirium in the ICU population ranges from 45% to 87%, with the possibility of higher numbers in a specialized ICU setting, and prevalence of delirium is higher in ventilated patients versus those who are not, increasing overall ICU days.⁵⁴ The average ICU length of stay increases by approximately 1.38 days when delirium is present, whereas intubated patients stay in the ICU a mean of 1.79 days longer.³⁵

Financial Impact of Delirium

The cost of delirium is far reaching, impacting the period during hospitalization and long after discharge with post-hospital care (e.g., inpatient, outpatient, nursing home, home health, rehabilitation and other services). In one study, the national financial impact of one-year healthcare costs attributed to delirium ranged from $143 billion to $152 billion. Estimated costs per patient range from $16,303 to $64,421 (in 2005 U.S. dollars).⁵⁵ Delirium prevention strategies can mitigate the adverse effects of the condition and save a significant amount of healthcare dollars.⁵⁰

30-Day Mortality Rate

Even after controlling for preexisting comorbidities, severity of illness, comatose state, and sedative and analgesic medication use, delirium remains an independent risk factor for mortality post-discharge.^49,56 For every ICU day spent in delirium, there is a 10% increased risk of death.²³ Delirium patients seen in the ED are also at risk. Elderly delirium patients discharged from the ED have a five-fold increase in mortality during the first 30 days after discharge. In these patients, mortality risk is more salient within the first three months with the risk being the strongest at 30 days post-discharge.⁴⁹

30-Day Readmission Rate

The first 30 days after hospital discharge are critical for patients who have experienced delirium during their hospitalization. Delirium patients have an increased risk of hospital readmission during this time, as delirium can precipitate a number of serious complications. Delirium patients are more likely to be admitted to the ED and ICU, and they have higher-acuity conditions than patients without delirium. Since many hospital readmissions occur through the ED, delirium patients are more likely to visit the ED due to the vulnerability of the condition compared with patients without delirium.³⁸

Fall Risk in Delirium

Preventable falls are the No. 1 cause of traumatic death in older adults.^37,50 Delirium is the leading contributor to hospital falls,³⁷ and in some instances, patients fall repeatedly during a delirious episode.⁵⁰ Implementing sound strategies to prevent delirium could help prevent falls.

Restraint Use in Delirium

Patients with delirium can display behaviors that increase risk of injury or interfere with treatment. As a result, the use of restraints to control agitated patients in the hospital is a common non-pharmacologic intervention. However, little evidence exists to show that restraint use in delirious patients is safe or effective. Restraints can lead to serious injury or even death in some cases and worsen agitation and delirium.⁵¹

Use of physical restraints can also influence the development of delirium. The more days physical restraints are used, the greater the risk of delirium.⁵⁷ Restraints should be used only as a last resort, in the least-restrictive manner and for the shortest possible duration.⁵¹

Summary & Recommendations

• Delirium is an expensive condition that leads to increased length of stay, hospital costs, mortality and worse clinical outcomes.
• Delirium monitoring and prevention should be a priority for hospital systems across Vanderbilt Health Affiliated Network.

References

¹Oldham, M, Flanagan, N, Khan, A, et al. Responding to ten common delirium misconceptions with best evidence: an educational review for clinicians. J Neuropsychiatry Clin Neurosci. 2018; 30(1):51-57. doi.org/10.1176/appi.neuropsych.17030065.

²Neufeld, K, Thomas, C. Delirium: definition, epidemiology, and diagnosis. J Clin Neurophysiol. 2013; 30(5): 438-442. doi.org/10.1097/WNP.0b013e3182a73e31.

³Ely EW. Confusion Assessment Method For The ICU (CAM-ICU): The Complete Training Manual. Critical Illness, Brain Dysfunction, and Survivorship (CIBS) Center. https://uploads-ssl.webflow.com/5b0849daec50243a0a1e5e0c/5bad3d28b04cd592318f45cc_The-Complete-CAM-ICU-training-manual-2016-08-31_Final.pdf. Revised August 31, 2016. Accessed September 19, 2019.

⁴Ely EW, Gautam S, Margolin R, Francis J, May L, Speroff T, et al. The impact of delirium in the intensive care unit on hospital length of stay. Intensive Care Med. 2001;27(12):1892-1900. doi.org/10.1007/s00134-001-1132-2.

⁵Han J. Delirium Triage Screen (DTS). Critical Illness, Brain Dysfunction, and Survivorship (CIBS) Center. https://uploads-ssl.webflow.com/5b0849daec50243a0a1e5e0c/5bb3782132fbb7857b2b15a6_DTS-Training-Manual-Version-1-0-09-01-2015.pdf. Revised September 1, 2015. Accessed September 22, 2019.

⁶Stollings J, Devlin J, Pun B, et al. Implementing the ABCDEF bundle: top 8 questions asked during the ICU Liberation ABCDEF Bundle Improvement Collaborative. Crit Care Nurse. 2019;39(1):36-45. doi.org/10.4037/ccn2019981.

⁷Delirium: Assess, Prevent and Manage. Critical Illness, Brain Dysfunction, and Survivorship (CIBS) Center. https://www.icudelirium.org/medical-professionals/delirium-assess-prevent-and-manage. Accessed September 22, 2019.

⁸Vasilevskis E, Ely EW, Speroff T, et al. Reducing iatrogenic risks: ICU-acquired delirium and weakness—crossing the quality chasm. Chest. 2010;138(5):1224-1233. doi.org/10.1378/chest.10-0466.

⁹Balas M, Pun B, Pasero C, et al. Common challenges to effective ABCDEF bundle implementation: the ICU Liberation Campaign experience. Crit Care Nurse. 2019;39(1):46-60. doi.org/10.4037/ccn2019927.

¹⁰Eeles E, White S, O’Mahony S, et al. The impact of frailty and delirium on mortality in older inpatients. Age Ageing. 2012;41(3):412-416. doi.org/10.1093/ageing/afs021.

¹¹Walston J, Buta B, Xue Q. Frailty screening and interventions. Clin Geriatr Med. 2018;34(1):25-38. doi.org/10.1016/j.cger.2017.09.004.

¹²BMJ Publishing Group. Quietly Delirious. Critical Illness, Brain Dysfunction, and Survivorship (CIBS) Center. https://uploads-ssl.webflow.com/5a56d43d5808f700012d4345/5d28cb527c51a259a57103ea_hypoactive-delirium-bmj-review.pdf. 2017. Accessed September 22, 2019.

¹³Han J. Brief Confusion Assessment Method (bCam): Instruction Manual v1. Critical Illness, Brain Dysfunction, and Survivorship (CIBS) Center. https://uploads-ssl.webflow.com/5b0849daec50243a0a1e5e0c/5bb3783be59e3422910fc5ba_bCAM-Training-Manual-Version-1-0-10-15-2015.pdf. Accessed September 21, 2019.

¹⁴Ely E. The ABCDEF bundle: science and philosophy of how ICU liberation serves patients and families. Crit Care Med. 2017;45(2):321-330. doi.org/10.1097/ccm.0000000000002175.

¹⁵Bellelli G, Morandi A, Davis DH, et al. Validation of the 4AT, a new instrument for rapid delirium screening: a study in 234 hospitalised older people. Age Ageing. 2014;43(4):496-502. doi.org/10.1093/ageing/afu021.

¹⁶Han JH, Wilson A, Vasilevskis EE, Shintani A, Schnelle JF, Dittus RS, Graves AJ, Storrow AB, Shuster J, Ely EW. Diagnosing delirium in older emergency department patients: validity and reliability of the delirium triage screen and the brief confusion assessment method. Ann Emerg Med. 2013; 62(5):457-465. doi.org/10.1016/j.annemergmed.2013.05.003.

¹⁷Brummel N, Vasilevskis E, Han J. Implementing delirium screening in the ICU. Crit Care Med. 2013;41(9):2196-2208. doi.org/10.1097/ccm.0b013e31829a6f1e.

¹⁸Patel M, Bednarik J, Lee P, et al. Delirium monitoring in neurocritically ill patients: a systematic review. Crit Care Med. 2018;46(11):1832-1841. doi.org/10.1097/ccm.0000000000003349.

¹⁹Wilson JE, Carlson R, Duggan MC, et al. Delirium and catatonia in critically ill patients: the delirium and catatonia prospective cohort investigation. Crit Care Med. 2017;45(11):1837-1844. doi.org/10.1097/CCM.0000000000002642.

²⁰Girard T, Exline M, Carson S, et al. Haloperidol and ziprasidone for treatment of delirium in critical illness. N Engl J Med. 2018;379(26):2506-2516. doi.org/10.1056/nejmoa1808217.

²¹Devlin J, Skrobik Y, Gélinas C, et al. Clinical practice guidelines for the prevention and management of pain, agitation/sedation, delirium, immobility, and sleep disruption in adult patients in the ICU. Crit Care Med. 2018;46(9):e825-e873. doi.org/10.1097/ccm.0000000000003299.

²²Huggins EL, Bloom SL, Stollings JL, Camp M, Sevin CM, Jackson JC. A clinic model: post-intensive care syndrome and post-intensive care syndrome-family. AACN Adv Crit Care. 2016;27(2):204-11. doi.org/10.4037/aacnacc2016611

²³Vasilevskis E, Pandharipande P, Girard T, et al. A screening, prevention, and restoration model for saving the injured brain in intensive care unit survivors. Crit Care Med. 2010;38(10 Suppl):S683-S691. doi.org/10.1097/ccm.0b013e3181f245d3.

²⁴Goals of HELP. Hospital Elder Life Program. https://www.hospitalelderlifeprogram.org/about/goals-of-help/. Accessed October 2, 2019.

²⁵What We Do. Hospital Elder Life Program. https://www.hospitalelderlifeprogram.org/about/what-we-do/. Accessed October 2, 2019.

²⁶Dedicated to Improving the Care of Older Adults. The John A. Hartford Foundation. https://www.johnahartford.org/about. Accessed October 4, 2019.

²⁷Fulmer T, Berman A, Mate K, et al. Age-friendly health systems: the 4Ms. ConsultGeri: a clinical website of The Hartford Institute for Geriatric Nursing. Try This. 2019 (35); 2019. https://hign.org/consultgeri/try-this-series/age-friendly-health-systems-4ms. Accessed October 4, 2019.

²⁸Pun BT, Balas MC, Barnes-Daly MA, et al. Caring for critically ill patients with the ABCDEF bundle: results of the icu liberation collaborative in over 15,000 adults. Crit Care Med. 2019;47(1):3-14. doi.org/10.1097/CCM.0000000000003482

²⁹Marra A, Ely E, Pandharipande P, et al. The ABCDEF bundle in critical care. Crit Care Clin. 2017;33(2):225-243. doi.org/10.1016/j.ccc.2016.12.005.

³⁰ABCDE=Caregiver. 2019. Critical Illness, Brain Dysfunction, and Survivorship (CIBS) Center. https://uploads-ssl.webflow.com/5b0849daec50243a0a1e5e0c/5bb3ef1b8f245ba1c8825d1c_Caregiver-ABCDE.pdf. Accessed October 9, 2019.

³¹Brummel N, Jackson J, Pandharipande P, et al. Delirium in the ICU and subsequent long-term disability among survivors of mechanical ventilation. Crit Care Med. 2014;42(2):369-377. doi.org/10.1097/ccm.0b013e3182a645bd

³²Carbone M, Gugliucci M. Delirium and the family caregiver: the need for evidence-based education interventions. Gerontologist. 2014;55(3):345-352. doi.org/10.1093/geront/gnu035.

³³Brown S, Bose S, Banner-Goodspeed V, et al. Approaches to addressing post-intensive care syndrome among intensive care unit survivors. A narrative review. Ann Am Thorac Soc. 2019 Aug;16(8):947-956. doi.org/10.1513/AnnalsATS.201812-913FR.

³⁴Jackson J. ICU liberation: Post-intensive care syndrome (PICS). Poster presented at: 48th Critical Care Congress, Society of Critical Care Medicine. February, 2019. San Deigo, CA.

³⁵Salluh JIF, Wang H, Schneider E, et al. Outcome of delirium in critically ill patients: a systematic review and meta-analysis. BMJ. 2015;350:h3129-h3129. doi.org/10.1136/bmj.h3129.

³⁶Ely EW, Shintani A, Truman B, et al. Delirium as a predictor of mortality in mechanically ventilated patients in the intensive care unit. JAMA. 2004;291(14):1753–1762. doi.org/10.1001/jama.291.14.1753.

³⁷Hshieh TT, Yue J, Oh E, et al. Effectiveness of multicomponent non-pharmacological delirium interventions: a meta-analysis. JAMA Intern Med. 2015;175(4):512–520. doi.org/10.1001/jamainternmed.2014.7779.

³⁸LaHue SC, Douglas VC, Kuo T, et al. Association between inpatient delirium and hospital readmission in patients ≥ 65 years of age: a retrospective cohort study. J Hosp Med. 2019 Apr;14(4):201-206. doi.org/10.12788/jhm.3130.

³⁹Granja C, Amaro A, Dias C, et al. Outcome of ICU survivors: a comprehensive review. The role of patient-reported outcome studies. Acta Anaesthesiol Scand. 2012;56(9):1092-1103. doi.org/10.1111/j.1399-6576.2012.02686.x.

⁴⁰Galvin J, Schmidt C, Zweig Y. The AD8: The Washington University Dementia Screening Test (“Eight-item Interview to Differentiate Aging and Dementia”). ConsultGeri: a clinical website of The Hartford Institute for Geriatric Nursing. Try This. 2018 (D14). https://hign.org/consultgeri/try-this-series/ad8-washington-university-dementia-screening-test. Accessed October 16, 2019.

⁴¹About Us. MoCA Montreal Cognitive Assessment. https://www.mocatest.org/about. Accessed October 14, 2019.

⁴²da Costa JB, Taba S, Scherer JR, et al. Psychological disorders in post-ICU survivors and impairment in quality of life. Psychol Neurosci. 2019 12(3):391-406. doi.org/10.1037/pne0000170.

⁴³Patel M, Jackson J, Morandi A, et al. Incidence and risk factors for intensive care unit-related post-traumatic stress disorder in veterans and civilians. Am J Respir Crit Care Med. 2016;193(12):1373-1381. doi.org/10.1164/rccm.201506-1158oc.

⁴⁴Hadjistavropoulos H, Pugh N, Nugent M, et al. Therapist-assisted internet-delivered cognitive behavior therapy for depression and anxiety: Translating evidence into clinical practice. J Anxiety Disord. 2014;28(8):884-893. doi.org/10.1016/j.janxdis.2014.09.018.

⁴⁵Ebell M. Screening Instruments for Post-Traumatic Stress Disorder. Aafp.org. https://www.aafp.org/afp/2007/1215/p1848.html. Accessed November 20, 2019.

⁴⁶Maisto S, Carey M, Carey K, et al. Use of the AUDIT and the DAST-10 to identify alcohol and drug use disorders among adults with a severe and persistent mental illness. Psychol Assess. 2000;12(2):186-192. doi.org/10.1037//1040-3590.12.2.186.

⁴⁷Outcomes Associated with ICU Delirium. Critical Illness, Brain Dysfunction, and Survivorship (CIBS) Center. https://www.icudelirium.org/medical-professionals/delirium/outcomes-associated-with-icu-delirium. Accessed October 23, 2019.

⁴⁸Vasilevskis E, Chandrasekhar R, Holtze C, et al. The cost of ICU delirium and coma in the intensive care unit patient. Med Care. 2018;56(10):890-897. doi.org/10.1097/mlr.0000000000000975.

⁴⁹Israni J, Lesser A, Kent T, et al. Delirium as a predictor of mortality in US Medicare beneficiaries discharged from the emergency department: A national claims-level analysis up to 12 months. BMJ Open. 2018;8(5):e021258. doi.org/10.1136/bmjopen-2017-021258.

⁵⁰Babine R, Farrington S, Wierman H. HELP^© prevent falls by preventing delirium. Nursing. 2013;43(5):18-21. doi.org/10.1097/01.nurse.0000428710.81378.aa.

⁵¹American Academy of Nursing. Don’t use physical restraints with an older hospitalized patient. Choosing Wisely. http://www.choosingwisely.org/clinician-lists/american-academy-nursing-physical-retraints-with-older-hospitalized-patients/. Accessed October 28, 2019.

⁵²Thomason JW, Shintani A, Peterson JF, Pun BT, Jackson JC, Ely EW. Intensive care unit delirium is an independent predictor of longer hospital stay: a prospective analysis of 261 non-ventilated patients. Crit Care. 2005 Aug;9(4):R375-81. doi.org/10.1186/cc3729.

⁵³Han J, Eden S, Shintani A, et al. Delirium in older emergency department patients is an independent predictor of hospital length of stay. Acad Emerg Med. 2011;18(5):451-457. doi.org/10.1111/j.1553-2712.2011.01065.x.

⁵⁴Cavallazzi R, Saad M, Marik P. Delirium in the ICU: an overview. Ann Intensive Care. 2012;2(1):49. doi.org/10.1186/2110-5820-2-49.

⁵⁵Leslie D, Inouye S. The importance of delirium: economic and societal costs. J Am Geriatr Soc. 2011;59:S241-S243.
doi.org/10.1111/j.1532-5415.2011.03671.x.

⁵⁶Abelha F, Luís C, Veiga D, et al. Outcome and quality of life in patients with postoperative delirium during an ICU stay following major surgery. Critical Care. 2013;17(5):R257. doi.org/10.1186/cc13084.

⁵⁷Pan Y, Jiang Z, Yuan C., et al. Influence of physical restraint on delirium of adult patients in ICU: a nested case-control study. J Clin Nurs. 2018;27(9-10):1950-1957. doi.org/10.1111/jocn.14334.

⁵⁸Sessler CN, Gosnell MS, Grap MJ, et al. The Richmond Agitation-Sedation Scale: validity and reliability in adult intensive care unit patients. Am J Respir Crit Care Med. 2002;166(10):1338-1344. doi.org/10.1164/rccm.2107138.

⁵⁹Devlin JW, Skrobik Y, Gelinas C, et al. Clinical practice guidelines for the prevention and management of pain, agitation/sedation, delirium, immobility, and sleep disruption in adult patients in the ICU. Crit Care Med. 2018;46(9):e825-e873. doi.org/10.1097/CCM.0000000000003299.

⁶⁰Lawton, MP, Brody, EM. Assessment of older people: Self-maintaining and instrumental activities of daily living. Gerontologist. 1969;9(3):179-186. doi.org/10.1093/geront/9.3_Part_1.179.

⁶¹Katz, S. Assessing self-maintenance: activities of daily living, mobility and instrumental activities of daily living. J Am Geriatr Soc. 1983;31(12):721-727. doi.org/10.1111/j.1532-5415.1983.tb03391.x.

⁶²Jackson JC, Pandharipande PP, Girard TD, et al. Depression, post-traumatic stress disorder, and functional disability in survivors of critical illness in the BRAIN-ICU study: a longitudinal cohort study. Lancet Respir Med. 2014;2(5):369-379. doi.org/10.1016/S2213-2600(14)70051-7.

⁶³Jutte JE, Erb CT, Jackson JC. Physical, cognitive, and psychological disability following critical illness: what is the risk? Semin Respir Crit Care Med. 2015;36(6):943-958. doi.org/10.1055/s-0035-1566002.

⁶⁴Parker AM, Sricharoenchai T, Raparla S, Schneck KW, Bienvenu OJ, Needham DM. Posttraumatic stress disorder in critical illness survivors: a meta-analysis. Crit Care Med. 2015;43(5):1121-1129. doi.org/10.1097/CCM.0000000000000882.

⁶⁵Righy C, Rosa RG, da Silva RTA, et al. Prevalence of post-traumatic stress disorder symptoms in adult critical care survivors: a systematic review and meta-analysis. Crit Care. 2019;23(1):213. doi.org/10.1186/s13054-019-2489-3.

⁶⁶Girard TD, Shintani AK, Jackson JC, et al. Risk factors for post-traumatic stress disorder symptoms following critical illness requiring mechanical ventilation: a prospective cohort study. Crit Care. 2007;11(1):R28. doi.org/10.1186/cc5708.