Aging Matters: Delirium in Hospitalized Elderly Patients: How You Can Help

THE CASE: An 83-year-old man presents to the emergency department after he fell down his basement stairs and was unable to walk. A subcapital hip fracture is diagnosed, and the patient undergoes surgery for placement of a hip endoprosthesis. Standard postoperative orders include intravenous morphine as needed.

On the first hospital day after removal of the catheter, the patient manifests confusion. He tries to get out of bed to use his bedside commode despite having been told repeatedly to ask for help. He is highly distractible and disoriented as to time and place. His level of consciousness fluctuates throughout the day and night from somnolence to mild agitation. He has no history of dementia.

How should this patient's confusion be evaluated and treated?

Delirium is characterized by altered level of consciousness, decreased attention span, acute onset, and fluctuating course. About 15% of elderly patients admitted to the hospital have delirium as a presenting or associated symptom, and delirium will develop in another 15% during hospitalization.

In hospitalized patients, delirium is associated with a 10-fold increased risk of death, a 3- to 5-fold increased risk of nosocomial complications, a prolonged stay, and postacute nursing home placement.¹ In addition, delirium during hospitalization predicts a poor functional recovery and increased risk of death up to 2 years after discharge.^2,3 Persistent delirium predicts an especially poor long-term outcome.⁴

Causes

The causes of delirium are often multifactorial. Predisposing and precipitating factors increase a patient's risk.^5-8 Predisposing factors include advanced age, dementia, and sensory impairment. Precipitating factors, such as Foley catheter insertion, room changes, and initiation of medication,may induce delirium in a susceptible person. Predisposing factors are often difficult to change but are useful in identifying high-risk patients. Precipitating factors are often modifiable and offer the opportunity for intervention.

A number of medications may precipitate delirium.⁹ Some experts believe that delirium is precipitated by medications with a high anticholinergic burden. This condition may be exacerbated by endogenous anticholinergic activity that occurs in persons with delirium.

Diagnosis

Clinical diagnosis may be difficult because delirium shares features with both dementia and depression. A thorough history taking is especially important, with particular focus on previous cognitive difficulties, mood disorders, and a review of medications. Traditional screening devices used for depression and dementia, such as the Geriatric Depression Scale and Mini-Mental State Examination, may not yield accurate results in the setting of comorbid delirium. Tests of attention, such as the Digit Span Test, may be useful in identifying those who have a decreased attention span, a cardinal feature of delirium. Family members can often provide valuable information about a patient's baseline cognitive status.

The criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), are the gold standard for diagnosis of delirium.¹⁰ Alternative criteria have been developed to help clinicians and nonclinical personnel diagnose and rate the severity of delirium. The Confusion Assessment Method (CAM) is commonly usedin inpatient settingsand is based on DSM-III-R criteria.¹¹ The NEECHAM scale is a nursing rating tool that screens for delirium, identifies patients at high risk, and assesses severity in medical inpatients.

Delirium can take several forms. Hyperactive delirium is the most easily recognized because patients with this form often fall or interfere with their care. Hyperactive delirium is characterized by psychomotor agitation, verbal aggression, disorientation, visual hallucinations, and combativeness.

However, two thirds of hospitalized patients with delirium are hypoactive and hypovigilant. Hypoactive delirium is characterized by somnolence and a decreased attention span. Although patients with this form are often overlooked, their delirium carries an equally poor prognosis.

A patient's cognition may fluctuate between the 2 subtypes of delirium, which results in a "mixed" delirium. Therefore, it is important to remain vigilant for delirium and obtain 24-hour reports on the patient's behavior from nursing staff and family members.

Clinical Approach

The evaluation and treatment of delirium should proceed in an organized fashion. Assess elderly patients for risk of delirium, and mitigate or eliminate possible precipitating factors when possible, especially in those with or at high risk for delirium. Nonpharmacologic interventions, such as environmental modification, and nursing protocols that focus on distraction, redirection, and reorientation are the recommended first steps in prevention and treatment. A multidisciplinary, multicomponent intervention may be useful in preventing delirium.^12,13

Treatment

Patients should be redirected and removed, if possible, from offending stimuli. Underlying disorders that precipitated the delirium should be treated. Use benzodiazepines with caution, because they may produce agitation. Neuroleptics may cause QT prolongation, extrapyramidal side effects, and akathisia. In general, it is best to start with low doses and titrate as needed. Once a medication has been found effective, schedule doses for times of peak agitation (such as before medical procedures and at bedtime).

Use physical and pharmacologic restraints only when all other options have been exhausted and the patient is interfering with care that is critical to his or her well-being (such as placement of an endotracheal tube or a central line). The use of physical restraints is associated with worsening delirium, injuries from falls, and debility. Most delirium can be managed without restraints in a "delirium room."¹⁷

Pharmacologic treatment of hypoactive delirium has not been extensively studied. Methylphenidate may be useful for opiate-induced delirium in a hospice setting.¹⁸

OUTCOME OF THE CASE

The patient was found to have postoperative hip pain as well as abdominal pain attributable to urinary retention. Because of his confusion, he was unable to communicate his pain to the nursing staff. Scheduled narcotics were prescribed. A postvoid residual test showed a volume of 700 mL, and an enlarged prostate gland was found on rectal examination. His blood pressure, pulse, and electrolyte level, as well as results of pulse oximetry and urinalysis, were normal. The postoperative hemoglobin level was 8.8 g/dL.

After a Foley catheter was reinserted, the abdominal pain resolved. The patient underwent a blood transfusion. A bed alarm was used to alert staff when he tried to get out of bed. He was placed in a geri-chair near the nurses' station and was frequently reoriented by the staff. His family helped by bringing in familiar objects from home, including his glasses. On further questioning, the family reported that he had been having memory problems; several months later, Alzheimer disease was diagnosed.

For this patient, the predisposing factors for delirium were dementia and visual impairment. Precipitating factors were urinary retention, postoperative pain, anemia, and environmental changes.