Journal of Gerontological Nursing

Evidence-Based Practice Guideline Supplemental Data

Evidence-Based Practice Guideline: Delirium

Patricia Finch Guthrie, PhD, RN; Shelley Rayborn, MSN, PHN, RN; Howard K. Butcher, RN, PhD


Delirium is a common cause of morbidity and mortality in hospitalized older adults often superimposed on dementia. Older patients with delirium are more likely than other populations to develop hospital-acquired infections, pressure ulcers, and immobility and nutritional issues, as well as to have increased health care costs, longer hospital stays, and long-term care following discharge. Interventions that prevent or mitigate the effects of delirium while promoting recovery are essential for caring for hospitalized older patients. This article is a summary of an evidence-based guideline that includes a framework for addressing delirium that focuses on predisposing and precipitating factors for delirium. In addition, the guideline includes evidence-based assessment and intervention principles, along with a review of reliable and valid assessment instruments. The guideline also identifies measurable outcomes for managing delirium and a quality improvement approach for improving outcomes. [Journal of Gerontological Nursing, 44(2), 14–24.]


Delirium is a common cause of morbidity and mortality in hospitalized older adults often superimposed on dementia. Older patients with delirium are more likely than other populations to develop hospital-acquired infections, pressure ulcers, and immobility and nutritional issues, as well as to have increased health care costs, longer hospital stays, and long-term care following discharge. Interventions that prevent or mitigate the effects of delirium while promoting recovery are essential for caring for hospitalized older patients. This article is a summary of an evidence-based guideline that includes a framework for addressing delirium that focuses on predisposing and precipitating factors for delirium. In addition, the guideline includes evidence-based assessment and intervention principles, along with a review of reliable and valid assessment instruments. The guideline also identifies measurable outcomes for managing delirium and a quality improvement approach for improving outcomes. [Journal of Gerontological Nursing, 44(2), 14–24.]

Delirium is a common cause of morbidity and mortality in hospitalized older adults, and may lead to permanent cognitive impairment and dementia (Greer et al., 2011). Delirium is a common occurrence for hospitalized older adults. A recently reported cohort study of 10,014 admissions to an acute medical unit between January 2012 and June 2013 indicated that the prevalence of delirium was 24.6% for patients 65 and older, with 7.9% having delirium superimposed on dementia (Reynish et al., 2017). According to Vasilevskis, Han, Hughes, and Ely (2012), 29% to 31% of general medical hospitalized patients not delirious on admission develop delirium during their hospital stay. Postoperative delirium varies from 11% to 51% depending on the type of surgery, such as cardiac, non-cardiac, and orthopedic (Inouye, Westendorp, & Saczynski, 2014). Patients with delirium are more likely to acquire infections, fall, develop pressure ulcers, require institutionalization, have dementia, have increased health care costs, and have longer hospital stays compared to patients without delirium (Inouye, Westendorp, et al., 2014). Delirium is also associated with higher mortality rates 1-year post discharge (Inouye, Westendorp, et al., 2014), and can result in permanent sequelae (Fong, Tulebaev, & Inouye, 2009). Persistent delirium exists in 21% of hospitalized patients 6 months after hospital discharge (Khan et al., 2012).

Variation in reported incidence of delirium in hospitalized patients is most likely due to setting, patient characteristics, method of case finding, and diagnostic criteria used to identify delirium (Greer et al., 2011). However, a consistent theme in the literature is that care processes are not designed to prevent common complications in older patients (Inouye, Westendorp, et al., 2014). Inadequate care processes, including lack of recognition of patients with delirium, lead to high rates of delirium (Greer et al., 2011).


The current article is a summary of the evidence-based practice guideline, Delirium (Sendelbach, Guthrie, & Rayborn, 2015) published by the University of Iowa Csomay Center for Gerontological Excellence. The full guideline, with complete graded level evidence, recommendations, references, and assessment tools, is available in electronic format (access The guideline provides direction for identifying risk factors, conducting appropriate assessments, and implementing effective strategies for prevention and treatment of delirium. The guideline emphasizes multi-component interventions, benefits of geriatric specialty units, and delirium prevention programs designed to prevent and mitigate delirium; and is designed for nurses and the interprofessional health care team who provide care for hospitalized older patients on general medical and surgical units.

The Delirium guideline on managing delirium for medical/surgical patients (Sendelbach et al., 2015) was a revision of the Acute Confusion/Delirium guideline that the University of Iowa published in 2009 (Sendelbach & Guthrie, 2009). The updated literature search from January 2009 to June 2014 included using the CINAHL, PubMed, Turning Research into Practice, PsycInfo, and Cochrane databases. The primary search terms of acute confusion, delirium, and cognitive impairment were first searched individually before combining with the key terms of prevention, management, interventions, assessments, instruments, multicomponent interventions, staff education, medical surgical, and nursing. In addition, the review included searching for delirium guidelines and protocols (2000–2014) from the National Government Clearinghouse, Registered Nurses' Association of Ontario, National Institute for Health and Care Excellence (NICE), and Hartford Institute for Geriatric Nursing.

The literature search was limited to evidence for hospitalized medical/surgical patients 60 and older. Non-English studies and guidelines, along with those related to substance abuse, traumatic brain injury, epilepsy, Parkinson's disease, psychiatric/mental health conditions, HIV, and end-of-life conditions were excluded. Literature about delirium related to care provided in critical care, post-acute care, the emergency department, and rehabilitation units were also excluded because of the focus on the medical/surgical population. Thirty-three systematic reviews, 92 single studies, and four guidelines were included in the appraisal and synthesis of the evidence for the 2015 guideline. For the current article, a subsequent review was completed for studies and guidelines from 2015–2017.

Definitions of Key Terms

Delays in care for delirium occur when nurses and the interprofessional team inappropriately diagnose cognitive changes as dementia or depression. It is therefore vital for clinicians to differentiate acute and persistent delirium from dementia and depression. The American Psychiatric Association (APA; 2013) defines delirium in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and identifies essential and associated features that are incorporated into many delirium assessment instruments. A hallmark of delirium is the inability of individuals to maintain or shift attention or maintain a sense of awareness regarding their environment. An important diagnostic characteristic is that delirium generally occurs within a relatively short period, such as a few hours or days, and has a fluctuating pattern. Delirium results in cognitive impairment that includes problems with memory, orientation, and language-related communication. Other characteristics of delirium are changes in the sleep–wake cycle; perceptual changes; changes in physical, emotional, and behavioral functioning; and psychomotor disturbances (APA, 2013). The NANDA-I nursing diagnosis of Acute Confusion (Code 00128) and Risk for Acute Confusion (Code 00173) are diagnostic labels (Herdman & Kamitsuru, 2018) that nurses may apply to patients before patients meet the specified criteria for a DSM-5 label of delirium. The diagnosis of “acute confusion” is broader than the diagnosis of delirium and includes prodromal changes not considered diagnostic for delirium.

Delirium Motor Subtype

Originally, delirium was classified into two motor subtypes, hyperactive and hypoactive; however, it was later identified that a patient could have a “mixed” motor sub-type, which includes hyper- and hypoactive delirium that fluctuate within short time periods (Adamis, McCarthy, O'Mahomy, & Meagher, 2017). Researchers identified these three clinical subtypes of delirium from patterns of motor activity, with some researchers identifying “no motor” as a fourth subtype (Slor et al., 2014). Clinicians are least likely to detect the hypoactive motor subtype (Rice et al., 2011), which occurs most frequently in older patients (Morandi et al., 2017). Evidence suggests this subtype is associated with worse patient outcomes than the other sub-types (Meagher et al., 2011). Adamis et al. (2017) found that alteration in motor behavior was related to cognitive and functional status in that hypoactivity was associated with impaired cognition instead of delirium. Hyperactivity was related to delirium and a decrease in functional status. Continued research is needed to clarify the relationship of motor subtypes with delirium and the effect of the different subtypes on outcomes. The motor subtypes of delirium are:

  • hyperactive motor subtype: increased quantity of motor activity, loss of control of activity, restlessness, and wandering;
  • hypoactive motor subtype: decreased amount of activity and speed of actions, reduced awareness of surroundings, listlessness, and reduced alertness or withdrawal;
  • mixed motor: symptoms of both hyper- and hypoactive delirium; and
  • no motor subtype: no evidence of any subtype within 24 hours (Meagher, 2009).

Delirium Superimposed on Dementia

Delirium superimposed on dementia (DSD) is when delirium occurs in patients with an underlying diagnosis of dementia (Morandi et al., 2012). DSD exists when an acute change in mental status occurs (within a short period of time from hours to days) that is characterized by a fluctuating course, changes in alertness, inattention, and disorganized thinking on top of dementia, which in contrast develops over months to years (Morandi et al., 2012). Nurses often do not assess for delirium in this population, because confusion is seen as a normal result of age-related changes or surgery (Yevchak et al., 2012). Nurses primarily document the presence of confusion and disorientation for hospitalized patients with delirium (Zalon, Sandhaus, Kovaleski, & Roe-Prior, 2017), which makes it unclear whether they are describing behaviors associated with dementia or DSD (Steis & Fick, 2012). However, the lack of recognition of delirium is an interprofessional problem stemming from inadequate knowledge and education of the health care team specifically about the benefits of early identification and treatment (Teodorczuk, Reynish, & Milisen, 2012). The patient's family is essential in identifying whether an acute change in cognition and behavior has occurred, which is most often a sign of delirium, or if the observed changes occurred over a longer period, which is most often a sign dementia.

Individuals at Risk for Delirium

Although anyone can develop delirium, not everyone is equally prone to the syndrome, with older adults at higher risk than other populations (Inouye, Westendorp, et al., 2014). Older individuals who are sick, functionally impaired, and have preexisting cognitive deficits are more likely to develop delirium when they are hospitalized (Inouye, Westendorp, et al., 2014). Prevention of delirium starts with clinicians recognizing risk factors and identifying patients at risk. The pathophysiology of delirium is unclear, but is likely due to various mechanisms resulting from acute medical illness, effects of medications, or complications from illness, surgery, or medical treatments. Although delirium is often transient and the result of acute illness, persistent delirium can occur that results in a chronic condition with significant functional decline and mortality. Fong et al. (2009) estimate that 30% to 40% of delirium cases are preventable.

A predictive delirium model based on the interrelationship between patients' baseline vulnerability on admission to the hospital and contributing factors occurring with hospitalization and illness serves as the framework for assessment and intervention for this guideline (Inouye, Westendorp, et al., 2014). This model assists nurses and the interprofessional team in individualizing interventions for prevention or management of symptoms based on the combination of factors specific to each patient's experience. Delirium is primarily multifactorial, and identification of a single cause frequently leads to an incomplete plan of care. Therefore, it is necessary for nurses and the interprofessional team to assess for two different types of factors when caring for older adults (Figure A, available in the online version of this article).

Delirium Algorithm

Figure A.

Delirium Algorithm

Predisposing factors are patient characteristics or age-related changes that are present on hospital admission that affect patients' vulnerability for developing delirium during hospitalization and are often unmodifiable (Table 1). Vulnerability may represent a lack of cognitive reserve, which is necessary for coping with noxious insults, or hospital-related factors, that occur with illness and hospitalization. For example, patients with preexisting cognitive impairments are at high risk for developing delirium and having prolonged delirium because of significant lack of cognitive reserve (Slor et al., 2014).

Factors that Cause Delirium

Table 1:

Factors that Cause Delirium

Precipitating factors precede the development of delirium and are noxious insults that are potentially modifiable and contribute to the development of delirium (Table 1). Patients with high vulnerability at hospital admission require fewer or relatively minor precipitating factors to cause an episode of delirium. Patients with low vulnerability at hospital admission require more precipitating factors to cause an episode of delirium. These patients have more reserve and it takes a greater level of insult for delirium to occur. The goal for nursing care is to eliminate or mitigate the potential precipitating factors unique to each patient's condition and circumstance, and to provide supportive interventions that address patients' predisposing factors.

Assessment Principles

In reviewing the evidence, there are principles that improve the approach for assessing delirium, which include:

  • recognizing that delirium in older adults is common, specifically in those with predisposing factors that increase risk for delirium (Inouye, Westendorp, et al., 2014);
  • recognizing that delirium may be superimposed on dementia and the need to differentiate baseline from acute changes in cognitive and behavioral function (Ahmed, Leurent, & Sampson, 2014);
  • incorporating standardized instruments for assessing cognition and presence and severity of delirium into nursing admission and daily assessment processes (Adamis, Sharma, Whelan, & Macdonald, 2010);
  • assessing for predisposing/vulnerability factors for delirium on hospital admission (within 24 hours) to identify patients at greatest risk for delirium (Inouye, Westendorp, et al., 2014);
  • assessing for predisposing/vulnerability factors from patients' history and physical assessments (preexisting cognitive impairment and dementia, severity of current illness, and advanced age are the most consistent risk factors for delirium [Inouye, Westendorp, et al., 2014]);
  • assessing for precipitating factors/noxious insults for delirium on admission (within 24 hours) and throughout the patient's hospital stay to prevent delirium in high-risk patients (National Clinical Guideline Centre, 2010);
  • using ongoing assessments of patients' clinical history; behavior; cognition; perception (i.e., misperceptions, hallucinations, paranoia, and delusions); function; and identifying concerns of patients, family, and the interprofessional team (National Clinical Guideline Centre, 2010);
  • assessing for perceptual changes that often go undetected when they are not directly observable by asking patients if they are seeing or hearing things they cannot explain (National Clinical Guideline Centre, 2010);
  • establishing the timeline for changes in cognition helps assist with identifying precipitating factors and initiating the most effective interventions and referrals for improving outcomes (Fong et al., 2009);
  • conducting thorough review and assessment of current medications to identify potential risk factors for delirium (Tullmann, Fletcher, & Foreman, 2012); and
  • educating nurses on assessing cognition, cognitive impairment, and features of delirium, and understanding factors associated with poor recognition of delirium prevent delays in care (Wand et al., 2014).

Assessment Tools

Instruments used in assessing delirium tend to be of three types: (a) mental status questionnaires, (b) observational tools or symptom checklists, and (c) combinations of observations and mental status questions. Mental status instruments directly test patients' cognitive performance and are used in conjunction with a delirium-specific instrument. Observational instruments involve the clinician observing the behavior of a patient during care to determine the presence of delirium rather than asking the patient to perform a cognitive task. The clinician scores the absence or presence of specific behaviors that the patient demonstrates when interacting with the clinician and environment. Advantages of observational instruments compared to mental status questionnaires include the minimal response burden for patients because patients' cognition is not tested directly, and the fact that clinicians may observe and evaluate behavioral function frequently. A primary disadvantage of observational instruments is that they do not directly test cognitive performance and behavioral function, but are dependent on the judgment of the clinician when observing the patient. This reliance on subjective assessment may produce unreliable assessments for delirium. For this reason, clinicians should use observational instruments in conjunction with tools that directly assess cognition.

The criteria for choosing the appropriate standardized instrument include the psychometrics of the tool, the person who will be using the instrument, the clinical feasibility of using the scale, patient acceptability or response burden, and need for a diagnostic or screening instrument rather than one that assists with monitoring cognitive function over time (Foreman, 1993). When selecting an instrument for an institution, clinicians need to be aware of training requirements for appropriate use and limitations associated with institutional resources for education.

Nurses and the interprofessional team may need to use a variety of instruments depending on the purpose of assessment, which includes assessing for the risk of delirium, diagnosing delirium, and determining the severity of delirium. On admission, patients with common predisposing factors may need their risk for delirium further evaluated; thus, a risk assessment instrument may assist with preventing delirium. When the interprofessional team suspects that delirium exists, an instrument that assists with diagnosing delirium is critical. However, diagnostic instruments that do not measure the severity of the condition are not helpful for monitoring delirium over time because they determine only presence or absence of the condition. The interprofessional team needs to identify whether severity of delirium is increasing or decreasing to evaluate the treatment plan. There are many delirium instruments in the literature, but not all have undergone full psychometric evaluation (Adamis et al., 2010). The following list of delirium instruments is not exhaustive, but includes commonly used instruments with strong psychometrics or the potential to improve practice.

The Risk Model for Delirium (RD) is a risk assessment tool for delirium that provides a weighted scale for predisposing factors. The instrument is used primarily for postsurgical hip fracture patients, but can be applied across acute care settings. Possible scores range from 0 to 20. Patients scoring ≥5 are considered high risk for delirium (Vochteloo et al., 2011).

The 4AT is a diagnostic tool for delirium. The tool has high sensitivity and specificity for the diagnosis of delirium in older adults (70 or older) in acute care settings (Bellelli et al., 2014). The 4AT includes four items to determine delirium. The first item addresses alertness, the second and third items involve cognitive assessments, and the fourth item is an assessment of change or fluctuation in mental status (Bellelli et al., 2014). The 4AT scores range from 0 to 12, with 0 indicating low possibility for delirium or severe cognitive impairment, 1 to 3 indicating moderate cognitive impairment, and a score ≥4 indicating delirium.

The Confusion Assessment Method (CAM) is a diagnostic, observational instrument closely correlated with the DSM-IV criteria for delirium and was developed for clinicians without psychiatric backgrounds to assist them in identifying delirium. The updated manual for the CAM (Inouye, 2009) recommends using other cognitive assessments with the CAM such as the Mini-Cog (Alagiakrishnan et al., 2007) or the Digit Span test (Leung, Lee, Lam, Chan, & Wu, 2011). Following the use of a standardized cognitive assessment, the interviewer uses a decision process outlined by the CAM to determine if delirium is present. Those using the CAM tool should have knowledge of the current DSM criteria for diagnosis. The CAM tool is also effective in detecting delirium superimposed on dementia (Morandi et al., 2012).

The 3D-CAM is a 3-minute diagnostic tool focusing on four features of the original CAM tool: Feature 1, acute change in cognition; Feature 2, inattention; Feature 3, disorganized thinking; and Feature 4, altered level of consciousness (Marcantonio et al., 2014). The 3D-CAM has high sensitivity and specificity in hospitalized older adult populations. The patient or family can report change in cognition and inattention (Features 1 and 2), or they can be observed by the screener. Disorganized thinking (Feature 3) and altered level of consciousness (Feature 4) are tested or observed by the screener. For a diagnosis of delirium, Features 1 and 2 and either Feature 3 or 4 must be present.

The Delirium Index (DI) is adapted from the CAM and is intended to be a measure of the severity of delirium based on patient observation by a non-psychiatrist clinician, without additional information from family members, nursing staff, or medical charts (McCusker, Cole, Dendukuri, & Belzile, 2004). Each of the seven domains of the DI are scored from 0 (absent) to 3 (present and severe). The total score ranges from 0 to 21, with higher scores indicating greater severity.

The Confusion Assessment Method-Severity (CAM-S; Inouye, Kosar, et al., 2014) is an instrument designed to measure the severity of delirium and is used in conjunction with the CAM algorithm. The CAM-S is not a diagnostic instrument, but quantifies the intensity of delirium symptoms. The scoring includes rating each system, except acute onset, with 0 (absent), 1 (mild), or 2 (marked). Acute onset or fluctuation is rated as 0 (absent) or 1 (present). The total score for the short form ranges from 0 to 7, with 7 representing the highest severity. The long form contains additional features rated 0 to 2, with the total score for the long form ranging from 0 to 19.

Description of Interventions

Studies indicate that delirium prevention is more effective in improving outcomes for hospitalized older adults compared to interventions focused on delirium treatment and management (Inouye, Westendorp, et al., 2014). Delirium has a multi-factorial etiology in which the presence of predisposing factors and interaction with precipitating factors increases patient vulnerability to development of delirium. The multi-factorial nature of delirium requires that multi-component interventions are used to reduce or eliminate modifiable factors that are causal for delirium (Reston & Schoelles, 2013). In a meta-analysis of the literature, multicomponent interventions decreased the incidence of delirium and prevented falls (Hshieh et al., 2015). There is strong evidence to support that multicomponent interventions that include mobilization; avoiding physical restraints; reorientation that is part of care; using devices that support vision and hearing; a review of psychoactive medications; infection prevention; and ensuring sleep, adequate fluids, nutrition, oxygenation, and pain relief, are effective in preventing delirium (Oh, Fong, Hshieh, & Inouye, 2017). Studies vary as to type of interventions included in the multi-component approach; however, the basic approach for multi-component intervention includes staff education, assessment, identification of risk for delirium, recognition of delirium, and interventions that address the identified risk and causal factors (Greer et al., 2011; Khan et al., 2012; Reston & Schoelles, 2013). Because of the multi-causal nature of delirium, the involvement of a multidisciplinary team is important for preventing and managing delirium (Oh et al., 2017).

Geriatric Specialty Units

The implementation of a specialized geriatric acute care unit is one approach hospitals are using for preventing and managing delirium. The type of specialized units with the strongest evidence to support use include the Acute Care for the Elderly units and Geriatric Evaluation and Monitoring or Geriatric Monitoring units (Bee Gek Tay, Chew Chan, & Sian Chong, 2013; Fox et al., 2013). Specialized units focus on the unique needs of older adults and preventing the functional decline that often accompanies hospitalization. Geriatric units provide staff trained in care for older adults and experts on preventing and managing delirium.

Delirium Prevention Programs

The most widely disseminated delirium prevention program is the Hospital Elder Life Program (HELP; Inouye, Baker, Fugal, & Bradley, 2006). The HELP program includes an organizational structure for program delivery and a multicomponent intervention approach that is cost-effective and improves patient outcomes (Rizzo et al., 2001). Specific interventions used in the HELP program focus on reorientation and sleep strategies, early mobilization, providing hydration and nutrition support, using therapeutic activities, and providing hearing and vision adaptations (Hshieh et al., 2015). The most important factors to sustain the program include internal organizational support, effective champions, modifications to fit with the specific organization's resources, and adherence and fidelity to the essential elements of the program (Bradley, Webster, Baker, Schlesinger, & Inouye, 2005). Program elements include:

  • interprofessional team oversight and coordination;
  • assistance from trained volunteers and nursing staff in implementing care;
  • use of protocols for targeting and addressing risk factors for delirium;
  • reduction of use and doses of psychoactive medications; and
  • education of nursing staff and volunteers.

Staff and Provider Education as an Intervention

The Precede–Proceed (Green & Ottoson, 1999) model of education is a proven approach for educational planning in health care and has been used in studies to evaluate the effectiveness of staff educational interventions for delirium as well as other health-related programs (Yanamadala, Wieland, & Heflin, 2013). The model indicates that an institution's design of staff educational programs should address needed resources, dissemination of information, and feedback mechanisms regarding expectations for performance.

Intervention Principles

Evidence supports the following principles for preventing delirium:

Pharmaceutical Interventions

There are no U.S. Food and Drug Administration–approved medications to treat delirium (Flaherty, Gonzales, & Dong, 2011). The evidence supports the following pharmacological principles for preventing delirium:

  • use of nonpharmacological approaches is recommended for preventing and managing delirium versus the use of pharmacological approaches (Oh et al., 2017). A recent meta-analysis demonstrated there is no evidence to support the use of antipsychotic medications in the prevention or treatment of delirium (Neufeld, Yue, Robinson, Inouye, & Needham, 2016);
  • use of the American Geriatrics Society updated 2015 Beer's list to identify medications to avoid when caring for hospitalized adults 65 and older (Salbu & Feuer, 2017). Medications on the list known to potentiate the development and increase the severity of delirium include benzodiazepine drugs, meperidine, antipsychotic agents, and non-benzodiazepine and receptor agonist hypnotic agents (Salbu & Feuer, 2017); and
  • use of equianalgesic dosing to obtain optimal pain management, choosing the least invasive route for administration of opioid medications, and selecting nonopioid pain medications for mild to moderate pain (Horgas, Yoon, & Grall, 2012).


The evidence from the literature indicates that adverse outcomes are common and should be prevented:

  • Delirium severity and persistent delirium at hospital discharge is associated with high mortality and morbidity rates (Witlox et al., 2010).
  • Patients with delirium during hospitalization have longer hospital stays, greater functional decline, higher likelihood of needing institutional care, and higher risk of developing dementia (Khan et al., 2012).
  • Long-term cognitive decline frequently occurs following delirium, with some patients never recovering to their baseline function (Inouye, Westendorp, et al., 2014).

To prevent adverse outcomes, a systematic quality improvement approach is needed that includes monitoring process and patient outcome indicators (Inouye, Westendorp, et al., 2014). Process indicators measure adherence to the essential elements of an intervention and ensure the strength of the intervention necessary to change outcomes. Adherence involves assessing health care clinicians' knowledge of delirium (because clinicians need education for screening and assessing delirium) and the use of standardized assessments and practice guidelines (Inouye, Westendorp, et al., 2014). Process monitors outlined in the Delirium guideline evaluate use of the guideline and consistency of implementing essential processes that prevent delirium. Outcome indicators improve when process indicators show consistent adherence exists. Outcome indicators identified in the Delirium guideline include: (a) incidence of delirium during hospitalization, (b) delirium at hospital discharge, (c) use of physical or chemical restraints, (d) patient safety incidents during episodes of delirium, and (e) return to previous functional status. Additional outcomes to consider measuring during hospitalization are delirium-free days and days of immobility or mobility. Because hospitalized older patients commonly experience a poor recovery post-delirium (Dasgupta & Brymer, 2014), measurement of outcomes for cognitive and physical functioning should continue in the next level of care, including home care, long-term care, and clinic settings. Hospital readmissions are common for discharged older patients who experience delirium (Gleason et al., 2015; Reynish et al., 2017); thus, hospital 30-day readmission rates and the number of days at home is essential to evaluate the quality of discharge planning and post-hospital care.

Because the knowledge base for delirium is rapidly changing and due to the number of articles on delirium published annually in a wide array of journals, keeping current regarding the latest information is challenging. Delirium-focused organizations, networks, and associations have been established to facilitate interprofessional research, collaboration, and practice, as well as to develop new research and researchers in the study of delirium (Table 2). Some of the sites provide access to tools, resources, and educational materials for health care professionals and families.

Delirium Resources

Table 2:

Delirium Resources


Delirium is a complex condition that is often not recognized. Prevention is the most important approach for managing delirium and includes assessing for predisposing and precipitating factors on hospital admission and throughout the patient's hospital stay; and using standardized assessment instruments and a multicomponent intervention approach aimed at eliminating or mitigating the effects of causal factors. Addressing delirium requires a systematic, interdisciplinary approach that includes adopting a national guideline that outlines principles for assessment and intervention accompanied with staff education and ongoing monitoring for process and outcome indicators that lead to continuous improvement of care.


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Factors that Cause Delirium

Predisposing FactorsPrecipitating Factors
Dementia or cognitive impairmenta,b,c,dUse of physical restraintsb,e
History of deliriumb,c,eIndwelling bladder catheterb,c,e
Comorbidity burdena,b,d,eMetabolic disturbancesb,e,i
Severity of illnessaPolypharmacyb,c
Advanced age (older than 70)a,b,fIatrogenic eventsb,e
Depression and psychotic disordersb,e,gPaine,j,k
Vision and/or hearing impairmenta,b,dInfection, urinary tract and respiratoryb,e
Functional impairmenta,b,cRetention of urine and fecese,k
DiabetesfFluid and electrolyte imbalanceb,c,e
Atrial fibrillationhImmobilizatione
History of stroke and neurological disordersb,hUrgent hospital admissionb,e
Living in an institutiondMedications with anticholinergic effecte,g
Critical limb ischemiaf,i
Emotional distresse
Sustained sleep deprivatione
Opioid medicationsd,j
Low hemoglobin or blood transfusionse,f
Hip fractures and surgeryc,d
Acute neurological diseasee,f

Delirium Resources

Network for Investigation of Delirium: Unifying Scientists (NIDUS)https://deliriumnetwork.orgNIDUS is focused on accelerating delirium research through multidisciplinary collaboration and serves as a network to support high-quality research.
American Delirium Society (ADS)https://www.americandeliriumsociety.orgThe ADS promotes research, education, and quality improvement to minimize the effect of delirium on patients.
Hospital Elder Life Program (HELP) for Prevention of Deliriumhttp://www.hospitalelderlifeprogram.orgHELP is a program designed to provide high-quality care for hospitalized older adults. The goals for the program are to maintain older adults' highest level of cognitive and physical functioning, maintain independence at discharge, assist with patient transition to home, and prevent hospital readmissions.
Australasian Delirium Association (ADA) health care professionals developed the association to bring scientific evidence together for improving practice.
European Delirium Association (EDA)http://www.europeandeliriumassociation.comThe EDA was started by professionals to serve as a facilitator for the work that needs to be done to advance understanding of the pathophysiology, phenomenology, and etiology of delirium.
American Nurses Association Prevent, Identify, Treat is the result of an interdisciplinary collaboration between the American Nurses Association and ADS.
iDeliriumhttp://www.idelirium.orgiDelirium is the International Federation of Delirium Societies that includes the ADA, EDA, and ADS. The aim is to unify the advocacy efforts for delirium and create a greater understanding of its global implications.

Dr. Guthrie is Director for Inter-professional Education, Practice, and Research and Assistant Professor, and Ms. Rayborn is Assistant Professor, Department of Nursing, St. Catherine University, St. Paul, Minnesota.

The authors have disclosed no potential conflicts of interest, financial or otherwise.

Copyright © 2018 Csomay Center for Gerontological Excellence.

Address correspondence to Patricia F. Guthrie, PhD, RN, Director for Interprofessional Education, Practice, and Research and Assistant Professor, St. Catherine University, 2004 Randolph Avenue, St. Paul, MN 55105; e-mail:


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