Home Delirium/Dementia Strategies to diagnose delirium in hospitalized patients

Strategies to diagnose delirium in hospitalized patients

August 2004
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Published in the August 2004 issue of Today’s Hospitalist

BOSTON “Before you enter the elderly patient’s room, you suspect that she might be delirious. Nurses have told you that the patient seems disoriented and confused, but you want to make a definitive diagnosis.

If your instinct is to enter the room and ask the patient to identify where she is, today’s date and the current president, however, you may want to try another approach. Geriatricians say that line of questioning is not appropriate to help you determine whether patients are suffering from delirium.

“Questions of orientation are neither very specific nor sensitive for detecting cognitive impairment,” said Anne Fabiny, MD, a geriatrician and director of geriatrics education at the Beth Israel Deaconess Medical Center in Boston. She discussed how to diagnose delirium in hospitalized elderly patients at the northeast regional meeting of the Society of Hospital Medicine in late June.

Not only are such general questions not specific, Dr. Fabiny explained, but patients can actually learn the answers to questions of orientation if they’re asked enough times. “I’ve had patients who say, ‘They keep asking me where I am and what day it is,’ ” she told the group. ” ‘Now I know I’m at Beth Israel Deaconess and I know it’s Tuesday.'”

If you’re trying to distinguish delirium from dementia, she explained, you’re better off assessing factors like the patient’s attention level. “A demented person doesn’t become inattentive until they’re in the advanced stages of illness,” Dr. Fabiny said. “A demented person living in a nursing home wouldn’t be inattentive unless she is also delirious or very demented.”

The confusion assessment method

Because inattention is such an important symptom of delirium, it is one of the primary diagnostic criteria of a screening tool known as the confusion assessment method (CAM). Dr. Fabiny said that the method is not only easy to use, but it is more effective than other tools like the Folstein Mini Mental State Exam.

“The Folstein tool was designed as a screening diagnostic tool for dementia, not delirium,” Dr. Fabiny said. “It’s been misused for years as a screening tool for delirium, but it was not designed for that purpose.”

The confusion assessment method, which was published in a 1990 Annals of Internal Medicine article, uses four measures. To make a diagnosis of delirium, you need to confirm the presence of both of the first two factors, and either the third or the fourth.

“¢ Inattention. When using the confusion assessment method, you should first measure the patient’s attention. If the person can’t pay attention to you, that’s the first sign that he may be suffering from delirium.

The Folstein exam uses “serial sevens” to test the patient’s attention, but Dr. Fabiny said that older women often complain that they have poor math skills. An alternative test is to spell the word “world” backwards, but that’s not particularly easy if English isn’t your first language.

“If you’re not a native English speaker and not welleducated,” she explained, “it’s not a valid test.”

What’s the best way to test for attention? Ask the patient to name the days of the week or the months of the year backwards. And if you have a patient who doesn’t speak English well, Dr. Fabiny said, use a translator.

“¢ Acute onset/fluctuating course. You need to collect information about both of these aspects of the patient’s mental state from ancillary sources like family members. “That’s always an important source of information when you’re trying to assess a patient’s cognitive function,” Dr. Fabiny said.

“¢ Disorganized thinking. “In my experience,” she explained, “disorganized thinking is almost always present. The way you test for disorganized thinking is to determine whether the person is tangential, rambling, incoherent or irrelevant in her responses.”

“Is her conversation unclear or does it seem to contain an illogical flow of ideas or unpredictable switching from subject to subject? Do you ask patients a question, only to have them answer a different question? Are they noticing things in the room and talking about them while you’re asking a question?”

“¢ Altered level of consciousness. Levels of consciousness are categorized as follows: alert (normal); vigilant (hyperalert); lethargic (drowsy but easily aroused); stuporous (difficult to arouse); or coma (unarousable). If a patient falls asleep while you’re speaking to him, Dr. Fabiny explained, he is probably delirious.

Diagnosing DELIRIUM

Once you’ve diagnosed delirium in a hospitalized patient, you need to identify its cause. Before you send your patient for a head CT or a lumbar puncture, however, Dr. Fabiny suggested running through the following mnemonic abbreviation, which spells the word delirium.

Drugs. Consider whether any drugs, either by themselves or in conjunction with other agents, are causing the patient’s delirium. “I once had a teacher say that whether older patients are confused or not,” Dr. Fabiny said, “a new symptom should always be considered a side effect of a medication until proven otherwise.”

Electrolytes/Endocrine/ETOH. Just because a patient is homebound, Dr. Fabiny said, doesn’t mean she doesn’t have access to alcohol. “I had one patient who was con- fined to a wheelchair but had alcohol delivered to her,” she explained. “The patient could still use the phone.”

Another patient had always enjoyed a glass of wine before dinner with her husband. When he died, the patient continued to have a glass of wine each night “but she had stopped eating dinner. When the patient arrived at the hospital, Dr. Fabiny said, she was inebriated.

Lack of drugs, e.g., pain medications or benzodiapine withdrawal. Because pain in older people can cause acute confusion, you need to explore whether the patient is suffering from untreated pain.

Infection. This is a well-known cause of delirium in older patients.

Reduced sensory input. Everyone knows that hospitalizing an older person can cause a delirium, but not everyone knows the simple things that can trigger cognitive problems.

“An older patient can come into the hospital without confusion,” Dr. Fabiny said, “but if he spends two days in there without his glasses, hearing aid and teeth, and the television is on all the time and the blinds are drawn, that can cause him to become confused, regardless of whatever underlying illness is present.”

She asks older patients if they need their eyeglasses, false teeth or any other essentials. She also makes sure that during the day hours, the blinds are open and the patient is up and out of bed when possible. “Make sure that they have everything they need to orient themselves to their environment,” Dr. Fabiny said.

Impaction of stool. “Whenever you’re seeing a confused older person,” she explained, “do a rectal exam. One possibility is that the patient hasn’t had a bowel movement in four days. Someone who is confused can’t tell you that.”

Urinary retention. “If you can’t figure out why an older man is confused and you don’t know how much urine is in his bladder,” Dr. Fabiny said, “put a catheter in him. Acute urinary retention in men can cause confusion.”

<bMyocardium. This category can include problems ranging from atrial fibrillation to acute MI.

“One thing that’s noticeable about this list is that the central nervous system is not on it,” Dr. Fabiny said. “There is no indication for a head CT or a lumbar puncture based on any of these possible causes of delirium. Put those procedures on the bottom of your list and order them only if there is a specific indication for them.”

“Make sure that everyone gets an EKG, and make sure that it is read,” she said. “Make sure you know how much urine is in a man’s bladder and ask about pain. Then, if you can’t find anything, consider a head CT.”

Expect fluctuation

When caring for patients with delirium, Dr. Fabiny said, you need to remember that the condition fluctuates. Everyone “especially the patient’s family “needs to understand that patients will experience periods of lucidity and periods of confusion.

“I have house officers who tell me that their patient was completely clear in the morning,” she explained. “Then later in the day, they get a call from nursing saying she is confused. They start wondering if something is going on.”

“Expect that when you see the patient in the morning,” Dr. Fabiny said, “she might be confused, and when you see her in the afternoon, she might be clear. The nurses don’t always understand that, so it’s helpful to remind everyone how a delirium presents and its usual course.”

Over time, those clear periods should become longer and the confused periods should become shorter. Be concerned if the patient appears to be getting better and then suddenly worsens.

“With these patients,” Dr. Fabiny said, “you need to consider whether a new medical problem is manifesting itself. Older hospitalized patients are at increased risk for iatrogenic complications.”

Finally, you need to explain to patients’ families that the delirium may last for up to two months before it clears.

“When you’re talking to the patient’s family at discharge,” Dr. Fabiny said, “it’s helpful to educate them about the typical course of a delirium. Explain that the medical problem has been treated and the patient is getting what she needs, but that the confusion may last a while.”

“I’ve seen patients bounce back to the hospital after they’ve been sent home with a spouse,” she explained. “Twelve hours later, the guy is confused and the wife is panicked. She thinks he’s sick again because nobody told her that this could go on for days, weeks or months.”

Edward Doyle is Editor of Today’s Hospitalist.

The confusion assessment method

When using the confusion assessment method (CAM), you need to look for the following elements:
1. Acute onset and fluctuating course and
2. Inattention and either
3. Disorganized thinking or
4. Altered level of consciousness

Handheld help for treating geriatric patients

A free version of the popular pocket guide, “Geriatrics at Your Fingertips,” is now available for handheld computers.

The handheld version of the guide offers information on clinical care, screening tools, medications and much more. The information is brief and appears in outline form.

The tool is available for handheld computers that use both the Palm and Pocket PC operating systems online. Free registration on the site is required.

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