The Pennsylvania Patient Safety Authority has seen an increase in the number of delirium-associated patient safety events reported through the Pennsylvania Patient Safety Reporting System over the past decade, with 446 events reported from acute care facilities between January 2005 and December 2014. Of these, 14.3% (n = 64) were identified as Serious Events resulting in patient harm. Predisposing factors for delirium identified in the reports included age 65 or older, male gender, preexisting cognitive impairment, depression, and severe illness. Categories of potential precipitating risk factors for delirium identified in the reports were intercurrent illness or other physiologic cause, specific medications, environmental factors, and surgery or procedures requiring sedation. Evidence-based guidelines and risk reduction strategies are available to assist healthcare providers to diagnose, prevent, and treat delirium. Implementation of these guidelines and strategies has the potential to improve clinical outcomes and decrease harm for patients at risk for developing delirium.
Delirium is a potentially preventable condition that has been associated with patient harm, up to and including death.1,2 Despite occurring frequently in hospitalized patients, delirium often goes undetected or misdiagnosed, particularly among older patients in whom delirium can be mistaken for dementia. While delirium may be superimposed on dementia, the two conditions are distinct.
Dementia is a chronic condition characterized by progressive decline in several areas of cognitive function, while delirium is a temporary confusional state characterized by sudden onset, a fluctuating course, and difficulty sustaining attention.3-5 These symptoms may also be accompanied by an altered level of consciousness.3,4 Three delirium subtypes have been recognized based on the level of psychomotor agitation displayed by patients: hyperactive, hypoactive, and mixed.3,4,6 All three types can be associated with hallucinations and delusions, though these perceptual disturbances are more prevalent with hyperactive delirium.7
Delirium incidence varies widely, ranging from 15%8 to 56%3 of hospitalized older adults, depending on variables such as age, comorbidities, care setting, and diagnostic criteria.8-12 This rate can reach as high as 75%13 for critically ill patients of all ages and 85%14 for older adults receiving end-of-life care. Researchers have identified two categories of risk factors influencing the development of delirium: predisposing factors (i.e., chronic risk factors that make a person vulnerable to delirium) and precipitating factors (i.e., acute insults that can trigger the onset of delirium). Of special concern, in patients with multiple predisposing factors, fewer or less severe precipitating factors are necessary to trigger the onset of delirium.15
The two predisposing factors associated with the highest risk of developing delirium during hospitalization are age 65 or older and preexisting cognitive impairment, particularly in the postoperative, intensive care, and palliative care settings. Other predisposing risk factors include depression, severe or terminal illness, metabolic derangements, prior stroke, poor functional status, decreased oral intake, sensory impairments, history of alcohol abuse, and male gender.6
Precipitating factors for delirium can be organized into four categories: (1) specific medications (e.g., sedatives, narcotics, anticholinergic drugs), (2) intercurrent illness or other physiologic cause (e.g., stroke, infection, substance withdrawal), (3) surgery or procedures requiring sedation, and (4) environmental factors (e.g., sleep deprivation, use of restraints, presence of medical device attachments such as intravenous or urinary catheters, intensive care unit [ICU] setting).4,6
Multiple serious outcomes have been associated with delirium, including increased morbidity, length of hospital stay, healthcare costs, institutionalization, and mortality.1,2 The risk for poor outcomes is increased when delirium goes undetected and untreated, which is estimated to occur in one-third to one-half of all cases, especially in cases of hypoactive delirium.10,16 Once thought to be a transient condition without long-term adverse effects, it is now recognized that even a single episode of in-hospital delirium can be associated with persistent cognitive impairment, functional decline, and increased risk of death up to a year following hospital discharge.1,2
Pennsylvania Patient Safety Authority analysts reviewed delirium-associated patient safety events reported through the Pennsylvania Patient Safety Reporting System (PA-PSRS). Analysts reading event reports were able to identify the event types, levels of harm, predisposing risk factors, and potential precipitating factors most commonly reported. Analysts also conducted a literature search to gather evidence-based guidelines and risk re-duction strategies available to assist healthcare providers to diagnose, prevent, and treat delirium.
Analysts queried the PA-PSRS database for events containing the terms “delirium” or “delirious” (including misspellings) that were reported over a 10-year period, from January 2005 through December 2014. These reports were then analyzed individually to identify events involving patients experiencing delirium. Reports containing the search terms without evidence of delirium occurring during the current hospitalization, or relevance to the event being reported, were excluded (e.g., a patient was administered psychotropic medication in error and was monitored for signs of delirium but remained cognitively intact; delirium assessments were not documented over several days in the ICU; a family member mentioned that a patient developed delirium due to morphine during a prior hospitalization). The remaining reports were analyzed according to submission date, event type, harm score, care area, and patient age. In addition, qualitative analysis was performed to identify predisposing risk factors and potential precipitating factors described in the event report narratives.
Analysts identified 476 events reported through PA-PSRS between January 2005 and December 2014 that contained the terms “delirium” or “delirious” (including misspellings). Of these, 446 events involving patients experiencing delirium were identified for further analysis.
Submission Date, Event Type, and Harm Score
Reports through PA-PSRS for events involving patients with delirium have increased over time, with an average of 16.3 events reported per quarter in 2014, compared with 2.5 per quarter in 2005 (see Figure 1). Of the 446 total delirium-associated events reported over this 10-year period, falls were the most commonly reported PA-PSRS event type (n = 158, 35.4%), followed by adverse drug events (n = 71, 15.9%). See Table 1 for a full list of delirium-associated PA-PSRS event types.
Figure 1. Delirium-Associated Events Reported through the Pennsylvania Patient Safety Reporting System, by Quarter, 2005 through 2014
PA-PSRS Event Type||
|Adverse drug reaction (not a medication error)||71 (15.9)|
|Complication of procedure/treatment/test||65 (14.6)|
|Error related to procedure/treatment/test||32 (7.2)|
|Skin integrity||28 (6.3)|
|Medication error||24 (5.4)|
|* Event types are defined by PA-PSRS taxonomy and are assigned to events by healthcare facilities at the time of report submission.|||
The majority of delirium-associated patient safety events were reported as Incidents without harm to patients (n = 382, 85.7%), with the remainder reported as Serious Events resulting in patient harm (n = 64, 14.3%).
Care Area and Patient Age
Delirium-associated events were reported in all facility care areas, with nearly half of all events (n = 222, 49.8%) reported from general care areas. Table 2 displays the number and percentage of delirium-associated patient safety events reported from each care area.
|General care (includes medical, surgical, telemetry, oncology, pediatric, transitional, and hospice inpatient units)||222 (49.8)|
|Psychiatric and chemical dependency (includes adult, geriatric, adolescent, and child psychiatric units and chemical dependency inpatient units)||55 (12.3)|
|Intensive care (includes medical, surgical, cardiac, transplant, and trauma critical care units)||52 (11.7)|
|Rehabilitation and long-term care||22 (4.9)|
|Emergency and trauma||21 (4.7)|
|Intermediate care||20 (4.5)|
|Operating room and perioperative (includes ambulatory surgical units and preoperative, operative, and postoperative care areas)||20 (4.5)|
|Diagnostic testing and procedural||18 (4.0)|
|Nonclinical, administrative, and other||12 (2.7)|
|Outpatient clinics||4 (0.9)|
Figure 2. Delirium-Associated Events Reported through the Pennsylvania Patient Safety Reporting System, by Patient Age Group, 2005 through 2014 (N = 446)
Nearly two-thirds of delirium-associated events were reported for patients age 60 or older (n = 294, 65.9%), though events were reported involving patients as young as under one year of age. Figure 2 shows the age distribution for these events in 10-year increments.
Predisposing Risk Factors
Male gender and age 65 or older were the most prevalent predisposing risk factors for delirium identified in reports of delirium-associated patient safety events, represented in 57.0% (n = 254) and 54.3% (n = 242) of total reports, respectively. Information gathered from event report narratives identified cognitive impairment as a potential predisposing factor in 14.3% (n = 64) of reports and depression in 10.8% (n = 48) of reports. Age 65 or older combined with cognitive impairment was identified in 10.5% (n = 47) of reports. Severe illness, as a predisposing factor, was assessed indirectly through the care area type, with 11.7% (n = 52) of events reported for patients receiving care in ICUs.
Potential Precipitating Factors
Intercurrent illness or other physiologic cause was the most prevalent category of potential precipitating factors for delirium identified in report narratives (n = 204, 45.7%), followed by specific medications (n = 131, 29.4%), environmental factors (n = 102, 22.9%), and surgery or procedures requiring sedation (n = 48, 10.8%).
Half of all reports contained information that identified a single potential precipitating factor (n = 225, 50.4%), nearly one-third identified multiple factors (n = 145, 32.5%), and the remainder did not mention any precipitating factors (n = 76, 17.0%).
Figure 3 shows the top specific factors mentioned in PA-PSRS event report narratives for each category of potential precipitating factors for delirium. For a full list of the potential precipitating factors identified in the PA-PSRS delirium-associated patient safety event reports, see Table 3.
Figure 3. Top Potential Precipitating Risk Factors for Delirium, by Category, as Identified in Delirium-Associated Events Reported through the Pennsylvania Patient Safety Reporting System, 2005 through 2014
Table 3. Potential Precipitating Factors* Identified for Delirium-Associated Events Reported to the Pennsylvania Patient Safety Authority, 2005 through 2014 (N = 446 reports)
PA-PSRS Event Reports
Analysts reviewing PA-PSRS reports have identified the occurrence of delirium, in and of itself, as the adverse event that is being reported. But in many cases, delirium is reported together with a secondary adverse event (e.g., patient fall, inappropriate removal of medical equipment). While the majority of events were reported as Incidents, some deidentified examples of Serious Events are as follows:
Falls resulting in fracture, intracranial bleeding, and/or death
Death following failure to recognize an arrhythmia due to patient removal of cardiac monitoring leads
Deep-vein thrombosis associated with use of an intravenous catheter in a patient arm that was restrained or covered with a tubular bandage (presumably to camouflage the catheter and/or prevent the patient from removing it)
The following are examples of delirium-associated patient safety events reported to PA-PSRS.* In each of these reports, predisposing and potential precipitating factors were identified from information contained in the event narratives.
Delirium during an intravascular procedure requiring emergency surgery. This report mentions two predisposing factors (i.e., 65 or older and male gender) and potential precipitating factors in two categories—intercurrent illness or other physiologic cause (i.e., coronary occlusion) and surgery or procedures requiring sedation (i.e., percutaneous coronary intervention).
This [>70-year-old male] patient was transferred from another facility for emergency percutaneous coronary intervention due to an acutely occluded coronary artery. During the procedure in the cath lab, the patient experienced acute delirium from an indeterminate cause. The patient unexpectedly attempted to get off the bed while the catheter was in the aorta. Due to this unexpected movement, the groin sheath became dislodged and caused vascular injury to the common femoral artery, aorta, and right ventricle. The patient underwent emergency coronary artery bypass grafting, as well as repair of the femoral artery and aorta.
Undiagnosed sepsis in a behavioral health patient. This report mentions two predisposing factors (i.e., age 65 or older and male gender) and potential precipitating factors in three categories—intercurrent illness or other physiologic cause (i.e., sepsis), specific medications (i.e., benzodiazepine and antipsychotic medication), and environmental factors (i.e., sleep deprivation).
A [>65-year-old male] was admitted to the behavioral health unit with an elevated temperature, anxiety, restlessness, and fluctuating orientation. He was on 1:1 observation for safety, and his condition progressively worsened with near delirium symptoms and insomnia, and lorazepam and haloperidol [were not effective]. During morning care, the patient was noted to become increasingly short of breath, with cyanotic lips and diaphoresis. His temperature rose to more than 103 with an elevated blood pressure and heart rate. An emergency code was called, and the patient was transferred to the intensive care unit with a diagnosis of sepsis.
Postoperative delirium in an ICU patient. This report mentions one predisposing factor (i.e., age 65 or older) and potential precipitating factors in three categories—surgery or procedures requiring sedation (i.e., the patient was recovering from an unspecified surgery), specific medications (i.e., opioid and anticholinergic medication), and environmental factors (i.e., ICU setting).
Delirium, disorientation, and confusion were identified postoperatively in a [>75-year-old female] with previous sensitivity to opioids that was undocumented in the electronic health record side effect profile prior to the current reaction. This reaction could have been precipitated and/or continued due to morphine, fentanyl, oxybutynin, and/or rocuronium administration. Other contributing factors were the patient’s age and ICU stay. All suspect medications were discontinued, and low-dose intravenous haloperidol every eight hours was initiated. The patient’s confusion slowly decreased, and she was back to baseline seven days later.
This report mentions one predisposing factor (i.e., age 65 or older) and one potential precipitating factor in the category of surgery or procedures requiring sedation (i.e., the patient underwent a computed tomography angiogram).
The emergency response team was called for tachycardia and altered mental status in an [>80-year-old male] patient following a computed tomography angiogram. On exam, the patient was awake, following commands, and oriented to place but disoriented to time and person. There was no focal motor weakness or sensory change. His heart rate was in the 120s with sinus rhythm, blood pressure was 165/83, and oxygen saturation was 95% on 2 liters of oxygen. The patient was transferred to the intensive care unit for evaluation of tachycardia and delirium.
Repeated removal of feeding tube by a delirious
patient.The following two event reports involve the same patient. No predisposing factors are mentioned, and the only potential precipitating factor mentioned is in the category of environmental factors (i.e., presence of a medical device attachment). These reports highlight the fluctuating nature of delirium.
The patient is a [>60-year-old female] found with her small bore nasogastric feeding tube pulled out and lying on the bed beside the patient. At last nursing assessment, two hours prior, the tube was in place and secured to the nose and cheek. The patient had pulled this tube out earlier, but at assessment she was alert and oriented, and the delirium screen was negative.
Patient found again with the feeding tube out and the oxygen tubing and collar removed from the tracheostomy. The patient is still alert and oriented times 3 with a negative delirium screen. She was unable to explain why the tube was pulled out again.
Lack of consensus regarding delirium
diagnosis.The following report does not mention any predisposing factors and only mentions one potential precipitating factor in the category of intercurrent illness or other physiologic cause (i.e., withdrawal). This report highlights the challenge faced in accurately screening for and identifying delirium, and it supports the need for an evidence-based, uniform approach to diagnosis.
All day, this [>50-year-old male] patient was trying to leave and had been talked out of it. Psychiatry saw the patient earlier and felt that the patient was suffering from delirium due to detox, but [psychiatry] was not willing to involuntarily commit him. The physicians and nurses thought that he was alert, oriented, and knew what he was doing. The patient demanded to leave, and the attending could not convince him to stay. He signed out against medical advice and was given his belongings. The sitter wheeled him to the front door because the patient said he called a cab. The administrator on duty that night got a call from the wife asking why he was home, because the psychiatric nurse had said we should not discharge him under any circumstances.
* The details of the PA-PSRS event narratives in this article have been modified to preserve confidentiality.
The Authority has seen a nearly seven-fold increase in the number of delirium-associated patient safety events reported over the past decade (see Figure 1). This increase should not be inferred to represent an increase in the incidence of such events. While this may be the case, the increase may also be the result of heightened awareness and improved recognition of delirium. This increase in the number of delirium-associated patient safety events reported to the Authority occurred at the same time that delirium received increased attention in clinical, healthcare services research, and patient safety circles. As evidence of this increased attention, the amount of scientific literature published each year on the topic of delirium has been steadily increasing over the past decade, with just 834 documents published in 2005 compared with 1,427 in 2014, according to a query of Scopus.17
During this same time period, delirium has received increased attention as a potentially preventable hospital-acquired condition. In 2008, the Centers for Medicare and Medicaid Services included delirium in the list of hospital-acquired conditions subject to nonpayment as part of the proposed changes to the inpatient prospective payment system;18 however, this was removed from the final rule during the public comment phase. While recognized as a hospital-acquired condition, it was not included in the list of conditions subject to nonpayment for three chief reasons: (1) evidence exists that delirium prevention protocols can only prevent 30 to 40% of all delirium cases; (2) there can be difficulty defining, diagnosing, and differentiating delirium from other conditions; (3) and delirium may be caused by many factors unrelated to clinical care of the patient.19
PA-PSRS Reports: Limitations and Key Findings
Because of challenges in screening for and accurately diagnosing delirium, the Authority recognizes that the reports identified in the current analysis most likely underrepresent the actual number of events occurring that involve patients experiencing delirium, particularly in the early years of the reporting program. Also, identification of predisposing risk factors (other than gender and age) and potential precipitating risk factors is limited to those described in the event narratives provided by reporters. Additional factors associated with these events may have been unaccounted for in the reports. For instance, in a report of postoperative delirium, anesthesia may have also been a precipitating factor; however, if anesthesia was not explicitly mentioned in the event report, only the surgical procedure itself could be identified as a precipitating risk factor. Despite these limitations, it is interesting to note that information contained in these reports is congruent with what has been found in the delirium research.
Delirium is associated with increased morbidity and mortality.1,2,4 In the current analysis, 14.3% of delirium-associated patient safety events reported through PA-PSRS from 2005 through 2014 were reported as Serious Events with harm to patients. In contrast, only 3.5% (n = 76,807 of 2,199,605) of all events reported by acute care facilities during the same 10-year time period represented Serious Events.20
The development of delirium is associated with predisposing and precipitating risk factors, and the etiology of delirium is often multifactorial.4,6,15 Predisposing and potential precipitating risk factors identified in PA-PSRS reports of delirium-associated patient safety events are in agreement with those found in the literature. Age 65 or older and male gender are predisposing factors identified in over 50% of reports. Cognitive impairment, depression, and severe illness are also mentioned in the reports. Of note, age and gender are required data entry fields in PA-PSRS, while information about other predisposing factors can only be gleaned from information submitted in the free-text event description. Other predisposing factors may have been present in a higher number of events but not mentioned in the detailed event description.
Nearly a third of the reports of delirium-associated events mentioned multiple potential precipitating factors. Information about potential precipitating factors can only be gleaned from information submitted in the free-text event description. These precipitating factors are labeled as “potential” due to the fact that the reports do not definitively identify them as causing the delirium.
Reducing Delirium in the Hospital Setting
Systematic review of studies evaluating the effectiveness of delirium prevention interventions suggests that staff education and multicomponent strategies to prevent or treat delirium in hospitalized patients are generally effective.21
Reducing delirium in older adults. One multicomponent delirium prevention program that has been well-studied and proven to be effective is the Hospital Elder Life Program (HELP). The Yale Delirium Prevention Trial evaluated the effectiveness of HELP and found it significantly reduced the number and duration of delirium episodes in older adults. HELP interventions are delivered by a specially trained interdisciplinary team that consists of a geriatric nurse specialist and an elder life specialist and may include a geriatrician, recreation therapists, physical therapists, and volunteers.22 Interventions provided by this team target six predisposing or precipitating factors for delirium that are amenable to intervention in the hospital setting: cognitive impairment, sleep deprivation, immobility, visual impairment, hearing impairment, and dehydration. More information about the program can be found on the HELP website at http://www.hospitalelderlifeprogram.org.
Reducing delirium in the ICU.
The American College of Critical Care Medicine published guidelines in 2013 for the management of pain, agitation, and delirium (PAD) in adult ICU patients. These guidelines were an update and revision to the 2002
Clinical Practice Guidelines for the Sustained Use of Sedatives and Analgesics in the Critically Ill Adult. The goal of the guidelines is to provide a road map for evidence-based best practices, including nonpharmacologic and pharmacologic interventions targeted to reducing all three conditions.23
The delirium guideline suggests specific screening tools (i.e., the Confusion Assessment Method for the ICU (CAM-ICU) or the Intensive Care Delirium Screening Checklist), nonpharmacologic interventions (e.g., early mobilization, sleep promotion), and pharmacologic interventions (e.g., administering dexmedetomidine rather than benzodiazepines for sedation in adult ICU patients with delirium unrelated to alcohol or benzodiazepine withdrawal). The guideline also suggests that the most effective method for implementing these practices is through incorporating the PAD guidelines into an institution-specific protocol, to be delivered by an interdisciplinary team.23
Reducing postoperative delirium in older surgical
patients.TheClinical Practice Guideline for Postoperative Delirium in Older Adults was published by the American Geriatrics Society in October 2014. This guideline is specific to patients age 65 or older and provides recommendations for nonpharmacologic and pharmacologic interventions to prevent and treat delirium in the perioperative setting. The interventions unique to this guideline include using regional anesthesia rather than general anesthesia (though the level of evidence was acknowledged to be low for this intervention); optimizing postoperative pain control, preferably with nonopioid pain medications; and avoiding medications postoperatively that are known to be precipitating factors for delirium, especially cholinesterase inhibitors and benzodiazepines. Similar to guidelines for the prevention and treatment of delirium in the general patient population, this guideline emphasizes the importance of developing a multicomponent, nonpharmacologic prevention plan delivered by an interdisciplinary team and providing ongoing delirium educational programs for healthcare professionals.24
Risk Reduction Strategies
The following strategies may be useful to healthcare facilities seeking to improve the diagnosis, prevention, and treatment of delirium.
Assess all patients for predisposing factors for delirium upon admission, in particular those age 65 or older and those with cognitive impairment or severe illness.25
Establish baseline cognitive status in patients with preexisting cognitive impairment or those at high risk for delirium by obtaining a detailed history from the patient’s family member or caregiver.4,6
Use assessment tools such as the Mini-Mental State Exam or Clock Drawing Test to establish baseline cognitive function and assess for changes as indicated.4,6,26
Monitor at-risk patients for the following signs and symptoms of delirium:4,6
Acute change in cognitive function
Inability to establish, sustain, or shift attention
Disorganized thinking, as manifested by rambling or incoherent speech, disorientation, or problems with memory
Altered level of consciousness, ranging from agitated and hypervigilant to lethargic and stuporous
Psychomotor agitation or retardation, hallucinations, delusions, emotional lability, and sleep-wake cycle disturbances
Consider screening at-risk patients using a validated tool, such as the Confusion Assessment Method (CAM) tool or the CAM-ICU (designed to be used with critically ill, intubated, and/or nonverbal patients).4,6,21,23,26-28
Implement a multicomponent delirium prevention plan tailored to each patient’s identified predisposing risk factors and potential precipitating factors.22,25
Consult a geriatric specialist for older adults, especially those who are frail, have multiple comorbidities, or are on multiple medications.4,22,25,29
Involve the multidisciplinary team in the delirium prevention program.22,23,25
Maintain continuity in caregivers, and avoid moving the patient to different locations when possible.25
Promote orientation by providing a calendar and a clock and explaining to the patient where he or she is, why he or she is there, who each staff member is, and what the role of each staff member is.22,25
Encourage visitation from family, friends, and people familiar to the patient.25
Provide cognitively stimulating activities, such as reminiscence.22,25
Prevent dehydration and/or constipation, and promote good nutrition by encouraging adequate intake of food and fluids.22,25
Treat intercurrent illness and physiologic conditions known to be precipitating factors for delirium, such as hypoxia, infection, pain, and alcohol or other substance withdrawal.23,25
Conduct a medication review, and adjust the patient’s medication regimen to decrease or eliminate polypharmacy and deliriogenic medications.25
Provide hearing and vision aids to correct for sensory impairments.22,25
Provide an environment conducive to sleep, and promote good sleep habits.22,23,25
Promote mobilization through ambulation or active range of motion regularly throughout the day.22,23
All of the interventions listed as risk reduction strategies for the prevention of delirium are also applicable to the treatment of delirium. In addition, the following strategies may be considered:
Enlist the help of a healthcare professional who is trained and competent in the diagnosis and treatment of delirium whenever possible.25 For older adults, consultation with a team of geriatric specialists has been proven to be effective.22 For younger adults with extreme agitation or life-threatening behavioral disorders, a psychiatric consultation is recommended.4
Identify and treat the underlying cause for the delirium (e.g., treat underlying infection, adjust medication regimen to avoid culprit drugs).25
Attempt de-escalation with verbal and nonverbal techniques in patients exhibiting psychomotor agitation and distress.25
Avoid restraint use. Consider the use of restraints only in patients who are violent and at risk of harming themselves or others, or in those who may be at risk for removing important devices necessary for care, especially in the ICU setting (e.g., endotracheal tubes, arterial lines).4
Consider short-term use of haloperidol (less than one week) only in distressed patients who do not respond to nonpharmacologic intervention. Start with a low dose and titrate up slowly, especially in older adults.4,25 Obtain a baseline electrocardiogram and monitor for prolongation of the corrected QT interval during treatment. Provide continuous cardiac monitoring for patients receiving intravenous haloperidol.30
Avoid the use of antipsychotic drugs in patients with Parkinson disease or Lewy body dementia.4,25
Assess the medical, cognitive, and functional status of delirious patients regularly until a return to baseline is observed.4,23
Consider a comprehensive geriatrics assessment or neuropsychological testing in patients whose cognitive and functional statuses do not return to baseline within one to two months of an episode of delirium.4
Delirium is a common syndrome in hospitalized adults, particularly those age 65 or older, and has been recognized as a hospital-acquired condition that can result in serious harm to patients. Risk for developing delirium is influenced by predisposing and precipitating factors, many of which are modifiable. Hospitals are encouraged to implement an interdisciplinary, multicomponent delirium prevention plan targeted to these contributing factors to improve clinical outcomes and decrease harm.
Cole MG, Ciampi A, Belzile E, et al. Persistent delirium in older hospital patients: a systematic review of frequency and prognosis. Age Ageing 2009 Jan;38(1):19-26.
Witlox J, Eurelings LS, de Jonghe JF, et al. Delirium in elderly patients and the risk of postdischarge mortality, institutionalization, and dementia: a meta-analysis. JAMA 2010 Jul 28;304(4):443-51.
Inouye SK. Delirium in older persons. N Engl J Med 2006 Mar 16;354(11):1157-65.
Marcantonio ER. In the clinic: delirium. Ann Intern Med 2011 Jun 7;154(11):ITC6-1-ITC6-16.
Lyons DL, Grimley SM, Sydnor L. Double trouble: when delirium complicates dementia. Nursing 2008 Sep;38(9):48-54.
Ting Hshieh T, Inouye SK. Delirium. Chapter 21. In: Williams BA, Chang A, Ahalt C, et al., eds. Current diagnosis and treatment: geriatrics. 2nd ed. New York: McGraw-Hill; 2014.
Boettger S, Breitbart W. Phenomenology of the subtypes of delirium: phenomenological differences between hyperactive and hypoactive delirium. Palliat Support Care 2011 Jun;9(2):129-35.
Marcantonio ER, Goldman L, Mangione CM, et al. A clinical prediction rule for delirium after elective noncardiac surgery. JAMA 1994 Jan 12;271(2):134-9.
Marcantonio ER, Flacker JM, Wright RJ, et al. Reducing delirium after hip fracture: a randomized trial. J Am Geriatr Soc 2001 May;49(5):516-22.
Rudolph JL, Jones RN, Levkoff SE, et al. Derivation and validation of a preoperative prediction rule for delirium after cardiac surgery. Circulation 2009 Jan 20;119(2):229-36.
Ely EW, Shintani A, Truman B, et al. Delirium as a predictor of mortality in mechanically ventilated patients in the intensive care unit. JAMA 2004 Apr 14;291(14):1753-62.
Rudolph JS, Marcantonaio ER. Postoperative delirium: acute change with long-term implications. Anesth Analg 2011 May;112(5):1202-11.
Ely EW, Shintani A, Truman B, et al. Delirium as a predictor of mortality in mechanically ventilated patients in the intensive care unit. JAMA 2004 Apr 14;291(14):1753-62.
Casarett DJ, Inouye SK; American College of Physicians-American Society of Internal Medicine End-of-Life Care Consensus Panel. Diagnosis and management of delirium near the end of life. Ann Intern Med 2001 Jul 3;135(1):32-40.
Inouye SK. Predisposing and precipitating factors for delirium in hospitalized older patients. Dement Geriatr Cogn Disord 1999 Sep-Oct;10(5):393-400.
Inouye SK, Foreman MD, Mion LC, et al. Nurses’ recognition of delirium and its symptoms: comparison of nurse and researcher ratings. Arch Intern Med 2001 Nov 12;161(20):2467-73.
- Scopus [database search]. [cited 2015 May 28]. Atlanta: Elsevier BV.
- Centers for Medicare and Medicaid Services. Medicare program; proposed changes to the hospital inpatient prospective payment systems and fiscal year 2009 rates; proposed changes to disclosure of physician ownership in hospitals and physician self-referral rules; proposed collection of information regarding financial relationships between hospitals and physicians.
Fed Regist 2008 Apr 30;73(84):23528-938. Also available at
- Centers for Medicare and Medicaid Services. Medicare program; proposed changes to the hospital inpatient prospective payment systems and fiscal year 2009 rates; payments for graduate medical education in certain emergency situations; changes to disclosure of physician ownership in hospitals and physician self-referral rules; updates to the long-term care prospective payment system; updates to certain IPPS-excluded hospitals; and collection of information regarding financial relationships between hospitals.
Fed Regist 2008 Aug 19;73(161):48434-9083. Also available at
- Pennsylvania Patient Safety Authority. [Annual reports, 2005 through 2014] [online]. [cited 2015 May 29].
- Greer N, Rossom R, Anderson P, et al.
Delirium: screening, prevention, and diagnosis—a systematic review of the evidence. Washington (DC): US Department of Veterans Affairs; 2011 Sep.
- Inouye SK, Bogardus ST Jr, Charpentier PA, et al. A multicomponent intervention to prevent delirium in hospitalized older patients.
N Engl J Med 1999 Mar 4;340(9):669-76.
- Barr J, Fraser GL, Puntillo K, et al. Clinical practice guidelines for the management of pain, agitation, and delirium in adult patients in the intensive care unit.
Crit Care Med 2013 Jan;41(1):263-306.
- American Geriatrics Society Expert Panel on Postoperative Delirium in Older Adults. American Geriatrics Society clinical practice guideline for postoperative delirium in older adults [online]. 2014 Oct 10 [cited 2015 Jun 5].
- National Institute for Clinical Excellence. Delirium: diagnosis, prevention and management [online]. 2010 Jul [cited 2015 May 29].
- Registered Nurses Association of Ontario. Screening for delirium, dementia and depression in older adults [online]. 2003 Nov [cited 2015 May 29].
- Inouye SK, van Dyck CH, Alessi CA, et al. Clarifying confusion: the confusion assessment method. A new method for detection of delirium.
Ann Intern Med 1990 Dec 15;113(12):941-8.
- Wong CL, Holroyd-Leduc J, Simel DL, et al. Does this patient have delirium? Value of bedside instruments.
JAMA 2010 Aug 18;304(7):779-86.
- Siddiqi N, Stockdale R, Britton AM, et al. Interventions for preventing delirium in hospitalised patients.
Cochrane Database Syst Rev 2007 Apr 18;(2):CD005563.
- Wenzel-Seifert K, Wittmann M, Haen E. QTc prolongation by psychotropic drugs and the risk of Torsade de Pointes.
Dtsch Arztebl Int 2011 Oct;108(41):687-93.
Recognize factors that influence the development of delirium.
Recall the predominant event types and potential precipitating factors for delirium identified in events reported to the Pennsylvania Patient Safety Authority.
Differentiate predisposing and potential precipitating factors for delirium.
Distinguish between predisposing and potential precipitating factors that are more or less likely to be associated with delirium.
Identify strategies to improve the diagnosis, prevention, and treatment of delirium.
The following questions about this article may be useful for internal education and assessment. You may use the following examples or develop your own questions.
Question 7 and 8 refer to the following scenario:
Which of the following predisposing factors are associated with the highest risk for developing delirium during hospitalization?:
Age 65 or older and depression
Male gender and history of alcohol abuse
Cognitive impairment and age 65 or older
Prior stroke and depression
Which of the following statements about delirium is not true?
Delirium has been associated with increased risk of death up to a year following hospital discharge.
Hallucinations and delusions are perceptual disturbances that are most prevalent in cases of hypoactive delirium.
Use of haloperidol is suggested only in distressed patients who do not respond to nonpharmacologic intervention.
In patients with multiple predisposing factors, fewer or less severe precipitating factors are necessary to trigger the onset of delirium.
Which of the following event types in Pennsylvania is most frequently reported for delirium-associated events?
Adverse drug reaction (not a medication error)
Complication of procedure/treatment/test
The most prevalent category of potential precipitating factors for delirium identified in report narratives was ________________________________.
surgery or procedures requiring sedation
intercurrent illness or other physiologic cause
Which of the following scenarios describe a patient at highest risk for delirium?
A 45-year-old woman with a recent history of hospitalization for major depressive disorder is admitted for a total abdominal hysterectomy and will receive general anesthesia during the procedure.
A 60-year-old man with active alcohol abuse is hospitalized with pancreatitis and being treated prophylactically with oxazepam to prevent withdrawal symptoms.
A 70-year-old woman with diabetes and peripheral vascular disease is admitted for intravenous antibiotic treatment for cellulitis due to a cat scratch on her leg.
An 80-year-old man with vascular dementia due to multiple strokes is hospitalized for failure to thrive, dehydration, and evaluation for a possible small bowel obstruction.
All of the following are risk reduction strategies that a hospital can take to improve the diagnosis and prevention of delirium except:
Establish baseline cognitive status in patients with preexisting cognitive impairment or those at high risk for delirium by obtaining a detailed history from the patient’s family member or caregiver.
Screen at-risk patients using a validated delirium screening tool, such as the Confusion Assessment Method (CAM) tool or the CAM for the intensive care unit (CAM-ICU).
Limit the number of outside visitors for patients with hyperactive delirium in the intensive care unit
Consult a geriatric specialist for older adults, especially those who are frail, have multiple comorbidities, or are on multiple medications.
You are the nurse caring for a 70-year-old man admitted to the hospital for cardiac bypass surgery. After five days in the critical care unit, the patient is being transferred to your telemetry unit. When receiving report from the critical care nurse, you learn that the patient has a preexisting diagnosis of mild cognitive impairment due to a traumatic brain injury from a motor vehicle accident 10 years ago and that he was placed in bilateral wrist restraints while intubated but that he has been out of restraints since being extubated early this morning and “has been very quiet all day.”
Questions 9 refers to the following scenario:
In the above scenario, which of the following describes predisposing factors that suggest this patient is at high risk for delirium?
Age 65 or older, male gender, and cognitive impairment
Age 65 or older, cardiac surgery, and critical care environment
Age 65 or older, restraint use, and cognitive impairment
Age 65 or older, restraint use, and cardiac surgery
In the above scenario, which of the following describes precipitating factors that suggest this patient is at high risk for delirium?
Age 65 or older, cardiac surgery, and critical care environment
Age 65 or older, restraint use, and cardiac surgery
Critical care environment, restraint use, and cardiac surgery
Critical care environment, restraint use, and cognitive impairment
After receiving the patient in your unit, you orient the patient to his room and complete a physical assessment. The patient is awake and oriented to person, place, and time. Before leaving the room, you assist him to sit in a chair and demonstrate the use of the call bell and the television remote. An hour later, the patient’s daughter arrives and comes to the nurses’ station to speak with you, saying, “Something just isn’t right with my dad. He is acting strange, and I found him with his call bell and television remote tangled up in his intravenous tubing.”
In the above scenario, which of the following best describes the appropriate immediate actions to be taken?
Untangle the patient’s intravenous tubing, obtain information from the daughter about the patient’s baseline cognitive status, screen him for delirium using the CAM tool, obtain a repeat set of vital signs, and notify the physician of the daughter’s concerns and your assessment findings.
Untangle the patient’s intravenous tubing, obtain a repeat set of vital signs, screen him for delirium using the CAM tool, and reassure the daughter that this is normal for older patients just coming out of critical care and that his mental status should clear up within the next 24 hours.
Screen for delirium using the CAM tool, notify the physician of the daughter’s concerns, and request an order for bilateral wrist restraints to prevent the patient from pulling at his intravenous tubing.
Obtain a repeat set of vital signs, screen for delirium using the CAM tool, move the patient to an observation room, notify the physician, and request an order for haloperidol in case the patient gets more confused overnight.