This essay explores acute confusion in elderly hospital patients. It was found that a high proportion

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Acute confusion and the hospitalised elder

Introduction

This essay explores acute confusion in elderly hospital patients. It was found that a high proportion of hospitalised elders develop acute confusion, with some studies indicating incidence levels may be as high as 50% (Inouye 2000). Elders that develop acute confusion, or delirium, have longer hospital stays, increased mortality, and are less likely to resume independent life in the community than their non-confused counterparts (Inouye 2000, Aditya & Sharma 2003).

Elements that contribute to the development of delirium in elders were next examined to find that elders accumulate a number of predisposing factors through the ageing process. They have reduced physical reserves, more chronic illnesses, and are often prescribed multiple drugs for their conditions; all of which make them more vulnerable to minor precipitating events. Precipitating events that can induce delirium in the elderly may not cause delirium in younger, more hardy individuals. Infection, dehydration, hypoxia, pain, sleep deprivation or additional medications have all been described as possible precipitating factors.

Considering that delirium often heralds adverse outcomes for the elderly, it was interesting to note that this condition is rarely diagnosed or adequately managed. Attitudes of health care staff were examined to understand why this neglect occurs. Lastly, preventative measures and management recommendations were briefly reviewed.

Acute confusion and the elderly patient

Acute confusion is defined as "...a state of transient brain dysfunction that has an acute onset, brief duration, and fluctuating course” (Mentes, Culp, Maas, & Rantz 1999:96). Neelon and Champagne (cited in Mentes et al. 1999:96) further describe acute confusion as:

... a spectrum of nonadaptive psychophysiologic responses characterized by disordered cognition (which includes alterations in perception, thinking, and memory); dysfunction of the reticular activating system (which influences both patient attention and wakefulness); and dysfunction of the autonomic nervous system (which influences both psychomotor and regulatory functions).

Acute confusion, also called delirium, is common in elderly hospitalised patients where it results in longer hospital stays and increased mortality (Inouye 2000). In addition, elders that develop delirium in hospital are more likely to be released into nursing homes rather than back into the community (Aditya & Sharma 2003). The introduction of better prevention, detection, and management strategies for acute confusion should improve outcomes for elderly patients.

Causes of acute confusion in elderly hospital patients

Elders are thought to have an increased risk for developing acute confusion due to their

reduced physical reserves, prevalence of chronic illness, reduced neural function (which may involve pre-existing cognitive impairment), and polypharmacy (Mentes et al. 1999). Inouye (2000) identified delirium as a complex and multifactorial process involving an interrelationship between precipitating factors superimposed on a vulnerable host. According to this researcher (Inouye 2000), even relatively benign insults can result in delirium if the patient is elderly and compromised through the ageing process. The significance of this model is the suggestion that multiple predisposing and precipitating factors for delirium may need to be addressed before symptoms will abate (Inouye 2000). Effective treatment may be difficult to achieve as it could depend on multiple diagnoses and interventions.

The American Psychiatric Association, or APA (1999) note that there are a number of serious and often treatable medical conditions that must be considered when patients display symptoms of acute confusion. Medical conditions that warrant investigation include (APA 1999): central nervous system disorders, such as head trauma, seizures or hypertensive encephalopathy; metabolic disorders,such as renal failure, hepatic failure, anaemia, hypoxia, hypoglycaemia, thiamine deficiency, fluid or electrolyte imbalance, or acid-base imbalance; cardiopulmonary disorders, including myocardial infarction, congestive heart failure, cardiac arrhythmia, shock, or respiratory failure; or systemic illnesses, such as infection, neoplasm, severe trauma, sensory deprivation, or temperature regulation problems. Diagnosis of a medical etiology for delirium will depend on physical examination, accurate histories from patients and family members, previous medical records, and laboratory results.

Commenting on treatable medical conditions that may precipitate delirium in the elderly, Inouye (2000) notes that electrolyte imbalances, particularly hyponatremia or hypercalcemia are important triggers that should be investigated. Likewise, hypoxia and hypercarbia can lead to delirium that may be difficult to diagnose (Inouye 2000). Oxygen saturation monitors may not give an adequate picture if red blood cell or haemoglobin concentrations are low. Diagnosing respiratory failure can be confounded further because older patients may fail to show typical signs and symptoms such as dyspnoea or tachypnoea. Arterial blood gas determinations should help eliminate or confirm respiratory causes of delirium (Inouye 2000). Also, elders frequently present with delirium in response to myocardial infarction or congestive heart failure rather than the more common symptoms of shortness of breath or chest pain delirium (Inouye 2000). Infection in elders is thought to be an important precipitating factor for delirium, especially infections of the urinary or respiratory tracts (Foreman & Zane 1996). Infections are easy to overlook in elderly delirious patients because they seldom show elevated temperatures or normal leucocyte responses (Inouye 2000).

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The APA (1999) note that substance use or withdrawal is a frequent cause of delirium for all patients. The duration of drug induced delirium will vary according to the half-life of the drug ingested and according to the the patient’s ability to store, metabolise and clear the drug (APA 1999). Underlying vulnerabilities are thought to predispose elders to drug induced delirium as reduced hepatic and renal function from ageing will slow the metabolism and excretion of drugs (Barker 1999). Altered circulation with age may result in drugs being preferentially shunted to the brain or other organs where they may cause toxic reactions at lower concentrations compared to younger cohorts (Baker 1999). Also, the possibility of drug interactions is increased as elders are often prescribed multiple drugs to counteract the effects of chronic illnesses (McMurray 2002). Polypharmacy, or the taking of three or more drugs (McMurray 2002), greatly increases the chance of adverse drug reactions. Ali (cited in Baker 1999) studied the potential for adverse drug reactions to find that when taking two drugs, the chance of adverse reactions was 6%. The potential for adverse reactions rises to 50% when patients take five drugs and 100% when 8 or more medications are taken together (Ali, cited in Baker 1999). The onset of delirium from substance intoxication may arise within minutes to hours for such drugs as cocaine or hallucinogens, or may develop after several days with other drugs like alcohol or barbiturates (APA 1999).

The APA (1999) list three classes of substances that may cause delirium, including: substances of abuse, such as alcohol, amphetamines, cannabis, and hallucinogens; medications, such as anaesthetics, analgesics, antihistamines, antiasthmatic medications, antimictobials, antiparkinsonian drugs, corticosteroids, lithium and psychotropic medications, narcotics, muscle relaxants and immunosuppressive agents; and toxins, such as organophosphate insecticides, carbon monoxide and carbon dioxide, and volatile substances such as fuel or organic solvents. From this extensive list, it is obvious that complete histories need to be taken from elders and significant others to ascertain which prescribed or over-the-counter medications are being taken. Inouye (2000) warns that drug and alcohol withdrawal are notable and often unsuspected causes of delirium in the elderly. So, it may be as important to find out what elders have stopped taking, as well as what they are taking.

Most reports in the literature suggest that predisposing vulnerabilities for elder patients pose the largest risk for developing delirium (see Schuurmans, Duursma, & Shortridge-Baggett 2001 for review). Increasing age, pre-existing cognitive impairment, severe illness and dehydration, or comorbidities have all been suggested as important risk factors (Schuurmans et al. 2001). Inouye and Carpentier (1996) studied factors occuring after hospital admission that might predict the onset of acute confusion. They identified five precipitating factors: use of physical restraints, malnutrition, more than three medications recently prescribed, use of bladder catheter, and any iatrogenic event (treatments or diagnostic procedures). They found that if scores of one point were attributed to each of these factors, then the potential for developing delirium could be calculated. Patients were at low risk if they scored 0 points (only 3% developed delirium). Intermediate-risk patients scored 1 to 2 points and had a risk of developing delirium of 20%. High-risk elders who scored 3 or more points were found to have a 59% chance of becoming acutely confused over the next 24 hours. Their research may prove important for identifying elders at risk; they concluded:

A simple predictive model based on the presence of five precipitating factors can be used to identify elderly medical patients at high risk for delirium. Precipitating and baseline vulnerability factors are highly interrelated and contribute to delirium in independent substantive, and cumulative ways (Inouye & Charpentier 1996:852).

Incidence and tools for assessment

Incidence rates reported for elderly hospitalised patients with delirium vary considerably. This wide variance is thought to be related to the different research methodologies and diagnostic criteria used (Mentes et al. 1999). There were a variety of patients included or excluded in each of the studies (cut-off age for inclusion varied and patients exhibiting delirium when admitted to hospital where sometimes included, sometimes not). The setting for the research also varied with medical or surgical wards, emergency departments and either smaller or larger hospitals serving as the setting for research (Mentes et al. 1999). Schuurmans et al. (2001) reviewed the literature to find that reported rates vary between 5% and 51.5%, with a number of researchers reporting elderly delirium incident rates to be roughly 25%. These figures attest to the pervasive nature of elderly delirium in hospitals.

Other factors contributing to variable rates of incidence include the variety of assessment tools used and the skill of those doing assessments. The Clinical Assessment of Confusion A (CAC-A) scale, the Confusion Rating Scale (CRS), and the NEECHAM Confusion scale are diagnostic tools developed to detect delirium. Of these the NEECHAM Confusion scale is considered to be most reliable (Schuurmans et al. 2001). However, this scale can not differentiate between chronic confusion, as seen with various dementing diseases, and acute confusional states (Schuurmans et al. 2001). The Confusion Assessment Method (CAM) was designed to differentiate between the two confusional states, but has shown varying degrees of reliability (Schuurmans et al. 2001). For the most part, this assessment tool has a tendency for the inclusion of false-positive results (Laurila, Pitkala, Strandberg, & Tilvis 2002). It has been suggested that CAM (see Appendix 1) is a quick and easy to use tool for screening, but that patients scoring positive for acute confusion should be further assessed using the Diagnostic and Statistical Manual of Mental Disorders (DSM), edition IV released by the APA in 1994 and presented below (cited in APA 1999):

Diagnostic criteria of DSM-IV for the diagnosis of delirium

A. Disturbance of consciousness with reduced ability to focus, sustain or shift attention

B. Changed cognition or the development of a perceptual disturbance

C. Disturbance develops in a short period of time and fluctuates over the course of the day

D. There is evidence from history, physical examination or laboratory findings that the disturbance is:

1. Physiological consequence of general condition

2. Caused by intoxication

3. Caused by medication

4. Caused by more than one aetiology

Nurses frequently fail to recognise or document delirium in elderly patients

If nurses fail to recognise delirium in the elderly as a sign of potentially life-threatening complications, then underlying, treatable medical causes will not be pursued. According to McCarthy (2003a), a staggering 33% to 95% of patients with acute confusion go unrecognised, or at least undocumented. Foreman (1996) reported that as many as 7 out of 10 patients who have delirium go unnoticed through hospital systems. While a lack of education on the part of nurses, inefficient diagnostic tools, or failure to assess patients on a routine basis may contribute to the low reporting or recognition of delirium, McCarthy (2003b:203) proposes that “the ability of nurses to recognize acute confusion and to distinguish it from dementia can be attributed to their personal philosophies about aging.”

McCarthy’s research (2003a,b) indicates that nurses ‘unwittingly’ have one out of three philosophical attitudes about ageing. They may have the decline perspective (DP), which sees cognitive impairment as a natural and inevitable part of the ageing process. Nurses who operate from this perspective see no need to probe, assess or question as confusion is expected in older patients. Nurses operating from the vulnerable perspective (VP) view cognitive decline as a frequent, but not necessarily ubiquitous occurrence among the elderly. Nurses with this perspective are ambiguous in their approach to assessment and investigation. Without validation from others that the patient is acting different from usual, these nurses tend to assume that the patient has symptoms that can be attributed to normal ageing and that interventions other than standard nursing procedures are unnecessary. The third philosophical perspective which guides nurses is described as the healthful perspective (HP). According to McCarthy (2003a), nurses with this perspective view ageing as a normal process. Cognitive dysfunction was thought by these nurses to be pathological or unusual. From the HP perspective, delirious elders were immediately a cause for assessment and investigation. This attitude is evident from an excerpt of an interviewed nurse presented by McCarthy (2003a:97):

...It’s rare that I see somebody who is really confused just because they’re old. It’s usually from a disease process. I think of confusion as something that is pretty dramatic, pretty significant...It’s a matter of—if their wounds were bleeding, would you wait and see? Would you say, ‘‘Well, maybe it’ll slow down a little bit?’’ I don’t think so.

If cognitive dysfunction is judged ‘normal’, little action will be taken to discover treatable causes of delirium and elders will suffer the consequences. McCarthy (2003a, b) suggests that student or staff awareness programs might help overcome stereotypical models that fail to recognise healthy ageing as an option.

Diagnosing delirium is not a straight-forward process, even for nurses with a ‘healthy perspective’. Patients may be either hypoalert or hyperalert, or they may fluctuate between the two states (Inouye 2000). Symptoms may come and go with periods of normal cognition in between (Inouye 2000). If nurses have little time because staff levels are inadequate, the hypoactive patient, who has reduced psycho-motor activity and is less responsive to stimuli, may not be properly assessed. In addition, dementia may be present in elders that have delirium, making identification of symptoms particularly difficult without additional information from family or others who know the patient (Mentes et al. 1999). (See Appendix 2 for comparisons between dementia and delirium.)

Successful delirium management strategies

Formalised programs adopted by hospitals have proved effective in preventing the occurrence of delirium in elderly patients and in limiting negative outcomes (Inouye, Bogardus, Charpentier, Leo-Summers, Acampora & Holford 1999, Inouye 2000, Flaherty, Tariq, Raghavan, Baksh, Moinuddin, &. Morley 2003). The success of these programs stems from a strong interdisciplinary approach to early assessment of patient risk, adoption of risk minimisation strategies, and a commitment to ongoing assessment. These successful programs also focus on education and staff support programs to engender a healthy perspective to ageing.

Preventative strategies found to be successful include (Inouye 2000, Iouye et al. 1999, Harvy 1996):

Early assessment of predisposing vulnerabilities (eg, cognitive function, chronic illnesses, hydration status, nutritional status, infection) is required so that appropriate strategies can be introduced to bolster the health of elder patients. Data gathered provides useful baseline information that can be used to assess therapeutic regimes.
Frequent communication is important as it reassures patients, promotes trust, helps to orient patients, and reduces anxiety. Clear and unambiguous communication about scheduled activities and treatments is thought to help orient patients to the hospital environment.
Family are involved when possible by discussing preventative strategies and encouraging their participation. Familiar faces were thought to help orientate and comfort patients in the hospital environment.
Cognitive function is maintained through therapeutic activities. Patients are encouraged to reminisce, discuss current events or other subjects of interest, play word games or participate in other activities to stimulate cognitive function.
Exercise activities are scheduled, as appropriate, to stimulate motor function and prevent problems with immobility.
The use of indwelling bladder catheters is minimised as these prevent mobility.
Patients are encouraged to use their glasses, hearing aides, and dentures⎯these help elders to interact with their environment and enable communication.
Non-pharmacological approaches are used to encourage sleep, such as warm milk, herbal tea, back rubs and relaxation music. Noise levels are minimised and medication and treatment schedules are coordinated to prevent sleep deprivation.

If prevention fails and delirium develops (as it still does, even using the best preventative strategies, albeit at a lower rate), then a concerted effort must be made to discover and treat precipitating factors. Prompt action can prevent further, potentially fatal, complications. Continuing assessment is important to gauge the effectiveness of therapeutic interventions. Patients who develop delirium should be managed, if possible, with a non-pharmacological approach using methods similar to those proposed for prevention (Inouye 2000). Inouye (2000) warns that medications with psychoactive effects (including sedative–hypnotics, narcotics, and anticholinergic drugs) are among the most frequent contributors to delirium. The use of these and other medications should always be reviewed whenever a patient displays signs of acute confusion.

Physical or chemical restraints are considered last-resort and short-term management strategies, used only with patients who become severely agitated or who pose a danger to themselves or staff (Flaherty 2003, Inouye 2000). Physical restraints are likely to compound the psychological distress already felt by acutely confused patients and may well contribute to the confusional state (Fletcher 1996). Chemical restraints may result in masking underlying problems, they may also have unwanted sedative effects or they may interact with already prescribed medications (Fletcher 1996). It is much better to manage agitated, confused patients with imagination and intelligence.

Conclusion

Elders are prone to develop acute confusion after being admitted to hospital. However, this condition is seldom diagnosed and rarely treated in a rational fashion by health care workers. Too often acute confusion is considered to be a natural occurrence that accompanies old age. Failure to assess risk factors and address underlying causes can result in extended periods of illness, and increased mortality.

Older patients who are admitted to hospital should be assessed for predisposing vulnerabilities so that appropriate therapeutic measures can be introduced. Levels of hydration, electrolyte imbalances, nutritional status, sensory deficits, infections, chronic illnesses, medication usage, and cognitive function should all be addressed as they are known to affect vulnerability to delirium. In addition, preventative measures that maintain cognitive function, encourage mobility, and orient the elder patient to the ward should be standard practice.

If delirium develops, precipitating factors should be immediately suspected and investigated. Prompt action at this stage can prevent further, potentially fatal, complications. Additional supportive measures based on old-fashioned empathy and care and the avoidance of physical or chemical restraints are recommended to help confusion abate and restore normal cognitive function.

References

Aditya BS, & Sharma JC 2003 Predictors of a nursing home placement from a non-acute geriatric hospital. Clinical Rehabilitation 17:108-113

American Psychiatric Association 1999 Practice guideline for the treatment of patients with delirium. (On line accessed August 12, 2003)

URL: http://www.psych.org/clin_res/pg_delirium_1.cfm

Baker H 1999 Medication issues. In: Nay R & Garratt S (eds) Nursing older people: Issues and innovations, MacLennan and Petty, Sydney: 266-280

Buckwalte KC, & Buckwalter JA 1998 Acute cognitive dysfunction (delirium). Archives of the American Academy of Orthopaedic Surgeons 2(1), Winter: 9-19

Flaherty JH, Tariq SH, Raghavan S, Baksh S, Moinuddin A, &. Morley JE 2003 A model for managing delirious older inpatients. Journal of the American Geriatrics Society 51:1031–1035

Fletcher K 1996 Use of restraints in the elderly. Advanced Practice in Acute and Critical Care 7(4), November: 611-620

Foreman M, & Zane D 1996 Nursing strategies for confusion in elders. American Journal of Nursing 96(4): 47-51

Harvey M 1996 Managing agitation in critically ill patients. American Journal of Critical Care 5: 7- 13

Inouye SK, & Charpentier PA 1996 Precipitating factors for delirium in hospitalized elderly persons: Predictive model and interrelationship with baseline vulnerability. Journal of American Medical Association 275(11), March 20: 852-857

Inouye SK, Bogardus ST Jr, Charpentier PA, Leo-Summers L, Acampora D, &

Holford TR, 1999 A multicomponent intervention to prevent delirium in

hospitalized older patients. New England Journal of Medicine 340(9):669-676

Inouye SK 2000 Assessment and management of delirium in hospitalized older patients. Annals of Long-Term Care: Clinical Care and Aging 8 (12): 53-59

Jacobson SA 1997 Delirium in the elderly. Psychiatric Clinics of North American 20(1): 91-110.

Laurila JV, Pitkala KH, Strandberg TE, & Tilvis RS 2002 Confusion assessment method in the diagnostics of delirium among aged hospital patients: Would it serve better in screening than as a diagnostic instrument? International Journal of Geriatric Psychiatry 17: 1112–1119

McCarthy M 2003a Situated clinical reasoning: Distinguishing acute confusion from dementia in hospitalized older adults. Research in Nursing and Health 26: 90–101

McCarthy M 2003b Detecting acute confusion in older adults: Comparing clinical reasoning of nurses working in acute, long-term, and community health care environments. Research in Nursing and Health 26: 203–212

McMurray A 2002 Community health and wellness: A sociological approach, 2nd edn. Mosby, Marrickville: 193-223

Mentes J, Culp K, Maas M, & Rantz M 1999 Acute confusion indicators: Risk factors and prevalence using MDS data. Research in Nursing and Health 22: 95–105

Ribby KJ, & Cox KR 1996 Development, implementation, and evaluation of a confusion protocol. Clinical Nurse Specialist 10(5):241-47

Schuurmans MJ, Duursma SA, & Shortridge-Baggett 2001 Early recognition of delirium: Review of the literature. Journal of Clinical Nursing 10: 721-729

Appendix 1

Diagnostic algorithm of the Confusion Assessment Method (CAM)

Feature 1. Acute onset and fluctuating course

This feature is usually obtained from a family member or nurse and is shown by positive responses to the following questions: Is there evidence of an acute change in mental status from the patient’s baseline? Did the (abnormal) behavior fluctuate during the day, that is, tend to come and go, or increase and decrease in severity?

Feature 2. Inattention

This feature is shown by a positive response to the following question: did the patient have difficulty focusing attention, for example, being easily distractible, or having difficulty keeping track of what has being said?

Feature 3. Disorganized thinking

This feature is shown by a positive response to the following question: was the patient’s thinking disorganized or incoherent, such as rambling or irrelevant conversation, unclear or illogical flow of ideas, or unpredictable switching from subject to subject?

Feature 4. Altered level of consciousness

This feature is shown by any answer other than ‘alert’ to the following question: Overall, how would you rate this patient’s level of consciousness? (alert [normal], vigilant [hyperalert], lethargic [drowsy, easily aroused], stupor [difficult to arouse], or coma [unarousable])

The diagnosis of delirium by CAM requires the presence of

features 1 and 2 and either 3 or 4

From Iouyne 2000

Appendix 2

Distinguishing Delirium from Dementia

Adapted from Ribby & Cox 1996 and Inouye 2000