Delirium is a medical condition manifested as a disturbance in consciousness and cognition occurring in a short time period. It occurs in about 10% to 30% of hospitalized medically ill patients.¹ In some at-risk groups — such as postoperative patients, the elderly, and patients with CNS conditions — the incidence may be as high as 80%.² Despite its frequency, delirium is still often missed, or diagnosed as a primary psychiatric condition. Because of the potential for complications and associated morbidity, delirium must be recognized early. As in many other situations in health care, nurses are frontline observers who can recognize beginning signs of delirium and initiate care.

Many causes

Delirium develops quickly, often within hours, and involves changes in level of consciousness, attention, and cognition. Delirium represents a significant decline from a patient’s previous level of functioning.³ Delirium can be described as a syndrome with multiple causes, which can include medical conditions such as infections, drugs, withdrawal from drugs or alcohol, hypoxia, and metabolic disturbances.^2,4

In older people, delirium is sometimes confused with dementia, and in a person already diagnosed with dementia, symptoms of delirium may be dismissed as part of the ongoing dementia process. In any patient, sudden changes in behavior, cognition, and mental status should be considered as possible signs of delirium and require clinical investigation. Most cases of delirium are not preventable and will likely result in complications that may lengthen the hospital stay, increase the cost of care, and increase mortality. For those reasons, a model for quick identification and effective treatment is needed. A model called the Delirium Abatement Program has been developed and should be used as best practice in cases where delirium is found.⁵

Some evidence exists that in the older compromised patient, delirium may persist even after hospitalization. Many of these patients return to nursing homes, where their continuing symptoms increase care needs. The Delirium Abatement Program is a model for providing care to patients admitted to skilled care facilities after a delirium episode. It consists of four phases based on best practices, designed to screen for signs and symptoms of delirium, assess and treat possible causes, prevent and manage complications, and restore the person to best cognitive status.⁵

In the elderly, the prognosis following delirium can be extremely grave. A review of 10 studies performed in different patient populations found that the consequences of delirium varied somewhat with the clinical course and subtype of delirium.⁴ Current mortality figures of between 10% and 65% put the fatality rate close to that of MI.⁶ Similar findings have been reported in follow-up studies of patients with delirium in medical and coronary ICUs.

In danger for delirium

Older patients with concomitant medical illness and dementia are at highest risk for delirium. Any infectious process, particularly of the urinary or respiratory tract; fecal impactions; and other minor illness may precipitate delirium. These patients will have higher mortality rates and are more likely to have increased functional impairment.⁷ Typical of this population would be an 85-year-old man in the early to middle stages of Alzheimer’s disease admitted to the hospital for treatment of dehydration secondary to mild influenza. He does not recognize his wife or daughter when they visit. Throughout the hospitalization, the patient is lethargic and incontinent and unable to feed himself. Since his wife cannot care for him at home in his present condition, he is referred to a nursing home.

While delirium is often associated with medical conditions in the elderly and dementia, a variety of other potential sources of delirium exist. Delirium associated with drugs, both prescribed and OTC, occurs frequently. The possibility exists for delirium in withdrawal states from either drugs or alcohol. Drug and alcohol histories should be obtained on all patients receiving medical care since the history may help in recognizing early signs of delirium and significantly reduce the potential for complications due to major withdrawal symptoms. Alcohol withdrawal delirium usually occurs in 48 to 72 hours after the last drink and appears as confusion, hallucinations, and agitation.⁸

Consider the following case history: A 43-year-old man is admitted for an elective hernia repair. On his initial nursing assessment, he states that he drinks six to eight beers per week. As anesthesia is being administered in the OR, the patient experiences a grand mal seizure. The procedure is stopped, and the patient is returned to the medical unit for further evaluation. The patient continues to be confused and disoriented and experiences periods of sedation alternating with periods of restlessness. On further contact with the family, the healthcare team learns that the patient usually drank four to six beers a day and had stopped his daily use of alcohol just two days before the surgery. Identifying patients like this who are at risk allows the healthcare team to initiate a protocol for managing withdrawal and minimizing significant delirium symptoms.⁵

In the postoperative patient, delirium can have multiple causes, including hypoxia and metabolic disturbances.³ Some patients are more vulnerable to delirium because of medical conditions or injuries requiring the administration of drugs that may increase confusion as a result of their anticholinergic properties .³ Opiates, such as morphine and oxycodone (Oxycontin), and psychoactive medications, such as haloperidol (Haldol) and risperidone (Risperdal), can contribute to confusion.³ Common medications including diphenhydramine (Benadryl); tricyclic antidepressants, such as amitriptyline (Elavil); and the proton pump inhibitors, such as omeprazole (Prilosec) and lansoprazole (Prevacid); have the potential for the CNS adverse effects of confusion and delirium in the elderly.

In the ICU

Environmental factors, including noise and lighting in the ICU, may contribute to delirium in the medically vulnerable patient. ICU patients with delirium are likely to have an extended stay in the ICU and spend a longer time sedated and intubated. Early assessment and treatment of underlying causes are important in the ICU patient to reduce morbidity and mortality. Critical care nurses recognize the importance of monitoring for levels of sedation and for delirium. Monitoring for sedation involves identifying the patient’s level of consciousness.^5,7 (See “Scales to measure delirium.”) One of the most effective tools for use in the ICU is the two-part confusion assessment method . One part is an assessment of overall cognitive impairment; the second includes four items that have the best ability to differentiate delirium from other types of cognitive impairment.⁹

Symptom picture

Criteria from the Diagnostic and Statistical Manual of Mental Disorders IV were found to be the most accurate in the early identification of patients with symptoms of delirium. The DSM-IV criteria will assist in the early diagnosis of delirium and indicate the need to treat underlying causes. The criteria most important in helping recognize the symptom picture are changing conscious state and cognition changes occurring in a short time frame.¹ (The fluctuation in conscious state often leads to differing reports from caregivers about the patient’s mental status.)

Impairment in attention and memory will also occur. Memory deficits are most often associated with recent events; long-term memory may remain somewhat intact, but confused. Other symptoms that may present are associated with subtypes of delirium and add to the confusing picture that may be seen.²

What type?

There are three subtypes of delirium: hyperactive, hypoactive, and mixed. A person with hyperactive delirium may be agitated and disoriented. It is not uncommon for psychiatric symptoms to be part of hyperactive delirium, and a person may be delusional and hallucinating. Patients experiencing hyperactive delirium can be difficult to manage, particularly in the acute care setting, where they do not understand or are not compliant to treatments. Hyperactive delirium is often misdiagnosed as a psychiatric problem or, in the case of a person with dementia, dismissed as a worsening of previously diagnosed dementia.

A patient with hypoactive delirium will present as confused, disoriented, and subdued. Levels of consciousness may fluctuate. The patient may have days and nights turned around, sleeping in the daytime and being awake for long periods during the night. Patients who have this symptom picture often will appear acutely depressed or catatonic.

Mixed delirium is especially difficult to manage because there is often significant emotional lability, with the person moving between hyperactive and hypoactive states. This subtype is particularly challenging to diagnose since the presenting picture may change at any time.

If a question exists about a possible underlying psychiatric diagnosis, it is helpful to note that a patient with a psychiatric diagnosis, such as schizophrenia , is likely to present with auditory hallucinations. In cases of delirium, visual hallucinations are most common. Visual hallucinations are often an indicator of toxicity due to substance abuse, withdrawal, and/or a metabolic disturbance.¹ A careful history taking will help to identify patterns of thought distortion and other psychiatric symptoms that have been present over time.

What nurses can do

Assessment of signs and symptoms that lead to the recognition and appropriate diagnosis of delirium is essential. Sometimes family members provide the first clues, and healthcare providers should always consider family members’ input in the assessment process.

Nurses will usually be the first members of the healthcare team to realize that a significant change is occurring in the patient’s condition. However, in the elderly demented patient identifying the signs of delirium is more difficult. This may be complicated by the presence of the hypoactive form of delirium or the mixed form, neither form being what nurses usually think of as delirium. The use of assessment tools, such as the confusion assessment method or the Minimum Data Set, the nationally mandated assessment tool for nursing home residents, will help ensure early assessment so that appropriate interventions can be initiated.^5,7,9

The treatment for delirium is to correct the underlying condition resulting in the symptom picture. This requires a careful review, including laboratory tests and ongoing treatment of previously existing conditions. Efforts to discover and treat underlying causes of delirium may require lab work and other diagnostic tests that the patient will not cooperate with. Nursing measures can be instituted to help reduce confusion and modify agitation.

In some situations, the patient may require one-on-one supervision. The presence of a family member or friend may help improve the patient’s orientation and cooperation. Nursing staff and family or friends staying with patients should reorient patients frequently with year, month, day of the week, and time of day. Remind patients that they are in the hospital and explain the reason for the hospitalization.

Safety first

Keeping patients safe is of utmost importance during delirium. Patients are confused and may want to “go home” or “get away” from staff members, who they believe are going to harm them. Patients may pull out catheters and IVs, fall out of bed, or wander. To reduce such risks, the physical environment should be kept as simple as possible. Often elevating the head of the bed will help with orientation to place. Checking on the patient at 15-minute intervals will help ensure safety and provides an opportunity to reorient the person frequently.

Although chemical or physical restraints may become necessary if the person remains agitated and does not respond to other interventions, the use of restraints should be kept to a minimum. Often physical restraints increase agitation and resistance. Medications to reduce agitation may be helpful, but medication interactions may lead to further confusion.

Face-to-face communication

Patients experiencing delirium often cannot process complex information. Communication with the patient needs to be done in short, simple, and concrete phrases, preferably face-to-face. Call the patient by name, and state your name each time you interact with the patient. Explain interventions before attempting them. At times when patients seem more lucid, inform them of their progress.

If the patient is hallucinating, the nurse should clarify reality with statements like “I understand you are seeing spiders on the walls, but there are no spiders here. I know you are frightened by what you are seeing, and I will have someone stay here with you for a while.”

If a patient becomes verbally abusive, nursing staff should ignore the comments and focus on what the person is feeling, using a calm and empathetic manner. A person who is delirious may become combative. If this occurs, the nurse needs to set firm and clear limits. In a calm, controlled voice the nurse should acknowledge what the patient is feeling, but let the patient know that he or she will not be allowed to hurt anyone.

Managing pain appropriately is also important since uncontrolled pain will contribute to restlessness and agitation. Since the person is not able to communicate, nurses must be able to recognize other signs of pain, such as grimacing and restlessness.⁵

Adjusting the environment

Both understimulation and overstimulation should be avoided. Absence of cues about the time of day and the hospital situation can add to confusion. Activity, light, and noise — including noise from overhead paging and machines — should be monitored. Unless absolutely necessary, patients should not be awakened at night since sleep deprivation will worsen the symptoms of delirium.

Clocks and calendars help orient the person. Whenever possible, a consistent staff — particularly a primary nurse who is familiar to the patient and will offer orientation regularly — is helpful. Television and radio offer diversion, but should not be left on continuously, and relaxing programs should be selected. If a patient is accustomed to wearing glasses or using hearing aids, they should be available. Maintaining activity will also help reduce confusion; if the patient is not ambulatory, full range of motion should be done three or four times daily.

If family members or friends are staying at the bedside, they can read the newspaper or a magazine to patients, which will calm and reorient them. Most importantly, nurses can reassure the patient and family that the delirium is temporary and will clear as the underlying condition improves. Educating the family is an important part of the nursing responsibility in caring for a person experiencing delirium.

If delirium persists, consults with a neurologist and a psychiatrist may be indicated. If severe, behavior disturbances may require the use of psychotropic medications, such as haloperidol, risperidone, and olanzapine (Zyprexa).³ Medications need to be used carefully since they can contribute to confusion.

Delirium is a serious medical syndrome that can occur in a variety of medical circumstances. Nurses are often the first to recognize the significant change in the patient’s condition, but at other times miss identifying the symptoms. Nurses need skills in cognitive assessment and environmental management of symptoms to help reduce the morbidity and mortality often associated with delirium.