AUSTIN, TEX. — Most palliative care patients will suffer delirium at the end of life, yet the condition is often misdiagnosed and underrecognized.
The prevalence of delirium reaches 56% in hospitalized elderly patients, 87% in the ICU, and 88% in advanced cancer patients—and may be as high as 100% in patients receiving palliative care at death, palliative care pharmacist Rosene Pirrello said at the annual meeting of the American Academy of Hospice and Palliative Medicine.
Delirium develops quickly, may fluctuate throughout the day, and presents with a variety of symptoms, including inattention, confusion, agitation, delusions, lethargy, stupor, and coma.
The consequences of delirium can be significant, said Ms. Pirrello, of the Institute for Palliative Medicine at San Diego Hospice. The condition can increase mortality and morbidity, result in prolonged hospitalizations, and reduce quality of life. In 99 terminally ill cancer patients who recovered from delirium, 73 (74%) remembered the episode, and of those, 59 reported the experience as distressing (Cancer 2009 Feb. 24 [doi:10.1002/cncr.24215]). Caregivers and spouses reported similar levels of distress.
How often is delirium overlooked? In 107 patients with terminal cancer who had all experienced delirium, the overall detection rate was 47%; just 20.5% of the cases of hypoactive delirium, the most prevalent and underrecognized subtype, were detected (Jpn. J. Clin. Oncol. 2008;38:56–63), said psychiatrist Scott Irwin, director of psychiatry programs at the San Diego institute. In his own review of 2,716 hospice patients at the institute, delirium was documented in 18% of home care patients and in 28% of inpatients.
“This is grossly underrecognized, not only in our setting, but in all settings,” he said.
Delirium management should ensure patient safety, assess causes, and address environmental issues, Dr. Irwin said. Delirium has many causes, with medications at the top of the list. Environmental interventions can include providing materials that orient patients to the surroundings, adequate but soft lighting, and sensory aids; maintaining caregiver consistency; limiting stimulation; and having companions at the bedside for safety.
Treatment is radically different depending on the context and goals of care. “Benzodiazepines are the medication of choice for settling patients at the end of life, but they are completely contraindicated in our mind in the management of potentially reversible delirium,” said Dr. Frank Ferris, director of international programs at the institute.
Because of the neurologic and physiologic changes that occur when a patient is dying, it is probably impossible to do anything more than settle an agitated patient, he said.
“How many of you have had patients and families say to you in the agitation and confusion of dying, 'Please, simply settle the patient; we can't stand to watch it'?” Dr. Ferris asked his audience.
Benzodiazepines such as lorazepam and midazolam are sedatives that can decrease agitation and relax skeletal muscles. But more important, they are amnesics, Dr. Ferris said.
“If you actually ask patients who are approaching the end of their lives—and I do this with virtually everybody—'If you get to a place where you are agitated and confused, do you want to experience that or not?' virtually everyone says, 'I don't want to experience it or remember it,' ” he said.
Neuroleptics are a better choice for potentially reversible delirium, in part because they may not cause sedation to the same degree that benzodiazepines do, they are not amnesics, and they may decrease the seizure threshold. Evidence suggests that older neuroleptics such as haloperidol are as safe and effective as newer agents, and they are cheaper and have more routes of administration.
All of the speakers stressed that delirium is not the same as dementia, although the two are often confused. Cognitive impairment is present in both, but rapid onset is unique to delirium. The differential diagnosis for delirium also includes depression, anxiety, and akathisia, Dr. Irwin said.
Tools that can help improve delirium recognition include the Confusion Assessment Method, which asks four simple questions and has a robust sensitivity of 94%–100% and specificity of 90%–95%, Dr. Irwin said.
Etiology is important because delirium is reversible in about 50% of cases, Ms. Pirrello said. An acronym that can bring to mind the many causes of delirium is I WATCH DEATH O, she said. The letters stand for Infection, Withdrawal, Acute metabolic changes, Trauma, CNS pathology, Hypoxia, Deficiencies, Endocrinopathies, Acute vascular events, Toxins or drugs, Heavy metals, and Other.
The speakers reported no relevant conflicts of interest.