Home Feature Getting serious about perioperative delirium

Getting serious about perioperative delirium

November 2008

Published in the November 2008 issue of Today’s Hospitalist

Over Memorial Day weekend this year, Neil Winawer, MD, evaluated a patient whose rapid deterioration left him between the proverbial rock and a hard place.

The patient, a 72 year-old woman, was fully appropriate when she presented to the medical clinic with a six-week history of fatigue and was found to be in complete heart block. She was promptly admitted to the ICU for a temporary transvenous pacemaker. The next day, however, she became agitated with all the hallmark features of delirium.

On the one hand, the patient’s heart block indisputably required a permanent pacemaker. On the other, Dr. Winawer “who directs the hospital medicine service at Grady Memorial Hospital in Atlanta “knew the patient’s delirium was a marker for increased morbidity and mortality.

“I kept saying, ‘I have a bad feeling about taking a delirious patient to the operating room, even if it’s only minor surgery,’ ” he says. “I was very concerned about her not being able to participate in her postoperative care, but the alternative was not much better.”

The patient was, he adds, at high risk for an iatrogenic complication because she had pulled at the transvenous pacer in her neck on several occasions. He suggested removing the temporary pacemaker, transferring the patient out of the ICU and waiting until the delirium cleared.

“My resident later confessed that he thought it was crazy to even bring that up as an option, as most delirious patients just come out of it,” Dr. Winawer says. Meanwhile, “the family was having difficulty understanding how their mom was fine just 24 hours before entering the hospital.”

At the end of the weekend, surgeons examined the patient “who was restrained and sedated on haloperidol but still delirious “and decided to proceed. The woman went to the operating room and died on the table. The autopsy and medical review of the case revealed “no conclusive diagnostic reason why.”

Dr. Winawer is quick to add that even if he had acted on his doubts, there is no guarantee the woman would have survived. But the biggest lesson of the story, he says, “is that you need to take delirium very seriously.”

While delirium may be as likely to result in morbidity and mortality as any other disease, he explains, hospitalists still harbor a major misconception: They tend to downplay or minimize its significance, thinking confusion is normal, particularly in elderly patients who are away from their homes. As hospitalists take a growing role in preoperative evaluations and perioperative management, the prospect of delirium in surgical patients needs to be much higher on hospitalists’ lists of concerns.

Surgical precipitants
Studies have shown that delirium develops in anywhere from 14% to 56% of elderly patients. Those patients have an in-hospital mortality rate of between 22% and 76% and are twice as likely to die within a year. “Delirium really is a medical emergency, a marker for badness on board,” Dr. Winawer says. “What is happening on a cellular level? No one knows, but there’s something going on.”

Dr. Winawer, who has been a hospitalist for 10 years and has published articles on perioperative delirium care, stresses that treatment strategies for perioperative delirium are no different than those hospitalists follow when medical patients develop delirium.

The one exception is that physicians need to look for certain specific precipitants related to surgery that can be corrected. These include postoperative infections, untreated pain, pulmonary embolisms or unexpected reactions to anesthesia.

The importance of preop evaluations
One important confounding precipitant of perioperative delirium that often goes unaddressed is drug or alcohol withdrawal. This can be a problem if patients minimize their alcohol consumption during the social history, Dr. Winawer says, or when physicians “don’t think there’s a need to prophylax them,” usually with a medication like Librium.

Dr. Winawer recommends that during preoperative visits, hospitalists ascertain whether patients might suffer from withdrawal during a hospital stay. Start by asking if patients consume alcohol, he says; if so, ask if consumption is daily. If the answer is “yes,” follow that by asking if they’ve ever become shaky or tremulous without it. Explain that the answer is important because “you’re going to be in the hospital, and you won’t be able to have the drinks you normally would.”

It is also important, Dr. Winawer says, to ask patients specifically about all the medications they take because many patients do not think of the products they buy over the counter as drugs. The most common class of agents associated with increased delirium risk is antihistamines, such as Benadryl, Tylenol-PM and Sominex. The active ingredient in these medications, diphenhydramine, can produce significant anticholinergic effects.

Other factors that put a patient at higher risk, he says, include underlying dementias, or psychiatric or cerebrovascular illnesses, and can be teased out by a good history. Hospitalists should also look closely at a patient’s renal and liver function as well, because worsening conditions in these areas can contribute to delirium.

Finding nothing to fix
While some interventions can prevent or mitigate delirium (see “Strategies to prevent delirium,” above), the reality is that some high-risk patients will become delirious no matter what you do.

Because there is usually no way to stop delirium from progressing or to shorten its course once it starts, Dr. Winawer says, hospitalists should provide supportive care to make sure delirium doesn’t lead to complications such as falls.

“In older patients, you sometimes can perform a series of tweaks and the delirium may be much better the next day,” he explains. For younger patients with fewer comorbidities, delirium usually represents a “much larger insult,” such as an infection or withdrawal.

In the case of the patient Dr. Winawer saw over the Memorial Day weekend, the first thing his team did was to check her blood glucose and oxygen levels. The next was to look for abnormalities in her electrolytes and rule out infection. “Her kidneys were fine,” he says. “We sent her urine several times to the lab to make sure we weren’t dealing with a UTI. She wasn’t on any medications at home that could potentially lead to withdrawal.”

The team also got a chest X-ray to make sure there was no pneumonia. “We considered a head CT, but the patient had no focal deficits, and transporting a delirious patient with a transvenous pacer was risky,” he adds. The autopsy of the brain revealed no evidence of stroke or hemorrhage.

Despite that thorough assessment, nothing was found. “That’s why delirium is frustrating sometimes,” Dr. Winawer says. “You can do all those things, but it doesn’t mean you are going to find something and be able to fix it.”

Deborah Gesensway is a freelance health care writer based in Sierra Madre, Calif.

Strategies to prevent delirium in the hospital
Once you conclude that a hospitalized patient may be at high risk for delirium, a few interventions may help stave off further deterioration. Neil Winawer, MD, who directs the hospital medicine service at Grady Memorial Hospital in Atlanta, says that studies have given a thumbs-up to the following strategies:

  • Regularly orient the patient. That includes raising window shades during the day; writing the date and day of the week on a blackboard in the room; and advising families to be at the bedside as often as possible.
  • Keep the environment as quiet and non-stressful as possible. Make sure that patients are not woken in the night for non-emergency care, such as taking vital signs.
  • Recommend early mobilization and minimize the use of restraints.
  • Make sure patients with sensory deprivation have their hearing aides and glasses.
  • Order adequate hydration.