Physicians, nurses and researchers have lots of quasi-official names for delirium: acute confusional state, altered mental status, even “subacute befuddlement,” said Edward Marcantonio, ACP Member, in his Internal Medicine 2009 session “Confusion about Confusion: Delirium in Hospitalized Older Adults.”
“Then there are the terms we use on the wards: ‘He's agitated or confused; she's out to lunch; or my favorite one to hear, ‘Your patient is acting like a wild man,’” Dr. Marcantonio said.
Whatever the term, delirium is common in hospitalized adults age 70 and older, and can have several negative short- and long-term effects. Research shows, for example, that 50% of surgical patients experience delirium after hip fracture, coronary artery bypass graft or abdominal aortic aneurysm repair, and 15% to 25% of general medical patients experience it at some point in their hospital stay, he said.
Short-term complications from delirium include having two to five times the risk of nosocomial complications and two to 20 times the risk of in-hospital death. Long-term, the condition is associated with functional decline, cognitive decline and higher mortality for up to two years. It's also expensive, increasing length of hospital stay by two to five days, and costing $60,000 more per year per patient, Dr. Marcantonio said.
As such, recognizing delirium is critical. Dr. Marcantonio recommended using the “Confusion Assessment Method” (CAM), which involves four features
- Feature 1: Acute change in mental status with a fluctuating course
- Feature 2: Inattention
- Feature 3: Disorganized thinking
- Feature 4: Altered level of consciousness
To qualify as delirious, a patient must have both Features 1 and 2, and either of Features 3 or 4. A word of caution, however: CAM is only as useful as the mental status exam, which is performed prior to its application.
“We don't usually interact with patients in a way that brings out their delirium. We say ‘Hi’ and ‘How are you feeling today’, and then leave thinking they are fine,” Dr. Marcantonio said. “If we ask more questions, it would help.”
Ideally, one should do a mini-mental status exam plus attentional testing, he added. If a physician has limited time, he or she should first test a patient's level of consciousness, and then their attention—i.e. “Are the lights on, and if so, is anyone home?,” Dr. Marcantonio said.
Formal methods to test attention include asking the patient to spell WORLD backwards or to recite the days of the week and the months of the year backwards.
While the most often recognized form of delirium is the hyperactive “wild man” variant, this is less common than the hypoactive “out of it” variant, where the patient doesn't move, doesn't eat and doesn't use the bathroom. The latter is sometimes confused with depression, Dr. Marcantonio said.
A workup on a delirious patient should include taking a careful history—from a family member and/or primary care doctor, if possible—in order to discover the time course of mental status changes. A physical examination is also important, as delirium can be a sign of a more serious, life-threatening condition, Dr. Marcantonio said.
Physicians should also do a review of the prescription and over-the-counter drugs the patient is taking, and find out about any recent drug additions or discontinuations. The biggest drug offenders tend to be sedative-hypnotics, opioid analgesics and anti-cholinergic drugs, he said. Laboratory tests should include CBC, electrolytes, glucose, urinanalysis, and chest X-ray. Testing drug levels and a toxic screen may be appropriate, too.
To treat patients with delirium, physicians should correct all reversible factors. Common reversible factors can be remembered by using the pneumonic DELIRIUM:
Electrolyte imbalance (dehydration)
Lack of drugs (withdrawal, uncontrolled pain)
Reduced sensory input (includes vision and hearing)
Intracranial (stroke, subdural—this is rare in older patients)
Urinary retention and/or fecal impaction (especially if post-op)
Recounting the story of two elderly patients who got new hips and knees so they could continue horseback riding together, Dr. Marcantonio noted that all physicians should keep this sort of end goal in mind when treating patients, delirious or otherwise.
“All of our patients have their proverbial horse,” Dr. Marcantonio said. “Our goal is to get them back on the horse and doing what they love to do.”