Home Feature How to detect delirium

How to detect delirium

October 2011

Published in the October 2011 issue of Today’s Hospitalist

With delirium affecting between one-sixth and one-half of all patients over age 65, hospitalists ought to be the experts on how to diagnose, treat and prevent such reversible confusion. But all too often, that’s not the case.

"The reality is that we “both as a system and as individuals “have a lot of trouble recognizing delirium," said hospitalist Ethan Cumbler, MD, director of the acute care for the elderly services at the University of Colorado Hospital in Denver and associate professor of medicine. Nursing studies have shown that between 17% and 74% of inpatient delirium cases are missed. "And let’s be honest," Dr. Cumbler added, "physicians probably fare worse because we spend less time with patients."

At a workshop on the hazards of hospitalization at this year’s Society of Hospital Medicine annual meeting, Dr. Cumbler and Melissa L. Mattison, MD, associate director of hospital medicine and codirector of the acute geriatrics unit at Boston’s Beth Israel Deaconess Medical Center, offered hospitalists tips on how to do a better job identifying patients who are developing delirium. They also discussed what hospitalists should do to prevent contributing to delirium in vulnerable patients.

Know the baseline
To prevent delirium, ask yourself these basic questions: Are patients’ personal possessions “glasses, dentures, hearing aids “stored away in the closet, rather than being within easy reach? Has diphenhydramine (Benadryl) been ordered to help with insomnia? And did you give the patient a Foley catheter out of habit or to make life easier for nursing? All happen often in hospitals, and they all increase your patients’ chances of developing delirium.

To be delirious, patients must have an altered level of consciousness, but that alteration can range anywhere from agitation to stupor. The key is "altered," which Dr. Mattison said can be a tough call for hospitalists who are meeting a patient for the first time. The onset "has to be sudden, not something that has been trending over a long period of time," she added. "This is a new condition."

Because hospitalists don’t know their patients well, Dr. Mattison said, "It’s important to get the baseline from the nurse, the nursing home, family, or friends." Without knowing whether a 95-year-old suffered from cognitive impairment prior to admission, she noted, doctors and nurses often assume that a patient’s inattention, stupor or confusion is his or her normal state, instead of something that’s developed in the hospital.

"Ageism happens," Dr. Mattison said, and can lead doctors to miss a diagnosis of delirium.

Telltale signs
Another identifiable feature of delirium is that its course fluctuates over hours or days, so understanding a patient’s history over time is important to distinguish delirium from dementia.

Another distinguishing characteristic of delirium: inattention, or what Dr. Mattison called a "decreased ability to focus." Every day, she said, nurses at her institution ask all patients age 80 and older a series of questions.

They first ask patients to name the months of the year backwards; if patients can do that, the questioning is over. "But if they can’t, we ask them to say the days of the week backwards," Dr. Mattison said. "If they can’t do that, we ask them to count backwards from 10."

If patients can talk, she added, it’s important to have a conversation in which you ask not only where they are, but what’s going on.

"Ask ‘Why are you here?’" Dr. Mattison said. "You will get a much clearer picture of that person’s thought processes, and you will be able to tell what their level of consciousness is during that finite period."

She also urged doctors to not just talk to patients, but to listen as well.
"Who do we miss?" asked Dr. Cumbler. "We miss that quiet, very elderly patient who has hypoactive dementia because we rely on the things that cause us trouble, the things that get us the phone calls."

The best test for diagnosing delirium is the four-element confusion assessment method (CAM) or CAM-ICU for patients in the ICU. Although using the CAM can be quick, it’s not always easy. The key features, Dr. Mattison said, are "an acute onset and a fluctuating course" and a patient who is "inattentive or distracted."

"If both of those are not present," she said, "the patient is not delirious."

In addition, patients must exhibit disorganized thinking through a conversation or have an alteration in consciousness. You can determine the latter by observing the patient over time or by talking to family, friends or caregivers.

"Any one feature in isolation does not make delirium," Dr. Cumbler said. "If it did, all my interns who are disorganized and illogical would be classified as delirious."

Deborah Gesensway is a freelance writer who covers U.S. health care from Toronto.

Is your patient delirious?

Cognitive assessment method (CAM)
To assess whether patients are delirious, you need to assess the following four key factors:

1. Acute onset and fluctuating course: Ask the family or caregivers, "Is this the way the patient always thinks or has something changed?"
2. Inattention, distractibility: Ask the patient to count backwards from 20, recite the days of the week backwards or spell "world" backwards.
3. Disorganized thinking, illogical or unclear ideas: Examine patient for signs of hyperactivity or hypoactivity.
4.Alteration in consciousness: Have a conversation. Ask questions like "What is a log made of?" or "Which is more likely to float: a large leaf or a small stone?" Scoring: To diagnose delirium, you need evidence of both Nos. 1 and 2, plus either No. 3 or No. 4.

Mini-cog test
Give patients three words to repeat, such as "ball, justice, tree." Have them repeat the words immediately and tell them you will ask for those three words later. Now, ask patients to draw a clock with the hands at
10 minutes after 11. After they draw the clock, ask them to repeat the three words.

Scoring: 2 points for a correct clock and 1 point for each correct word recalled after the clock is drawn. No points for an incorrect clock and no partial credit for the clock. A mini-cog score of 0, 1 or 2 predicts a four- to five-fold increased risk of developing delirium in the hospital, regardless of whether the patient carries a formal diagnosis of dementia.