November 28, 2016

If your anesthesia practice provides care for older patients, chances are you also encounter POD and delayed cognitive recovery on a fairly regular basis.  The American Geriatrics Society’s (AGS) Best Practice Statement on Postoperative Delirium, published in the February 2015 issue of the Journal of the American College of Surgeons, cites POD as the most common surgical complication in older adults.

An estimated 5-15 percent of older surgical patients and 62 percent of older hip fracture surgery patients experience POD.  Considering this frequency, along with the fact that the annual cost of delirium in the United States is estimated at $150 billion, and that more than one-third of inpatient surgeries in the U.S. are performed on patients 65 years or older (a number expected to double by 2020)¹, and that the population of Americans over the age of 65 now stands at a staggering and expanding 46 million, POD presents a major safety and public health issue.

According to the AGS, POD is “compelling as a quality improvement target”, in part, because of its frequency, but also because it is preventable in approximately 40 percent of patients.  Efforts to prevent or minimize this surgical complication can forestall “a cascade of deleterious clinical events, including other major postoperative complications, prolonged hospitalization, loss of functional independence, reduced cognitive function and death,” the Best Practice Statement notes.

Strategies for Practitioners

The Brain Health Initiative, a patient safety effort led by the American Society of Anesthesiologists (ASA), is bringing medical societies and other stakeholders together to develop a toolbox for clinicians to prevent POD, along with material to inform patients about risks and to help caregivers and providers ensure optimal safeguards for patients after discharge.  As Lee Fleisher, MD, chair of the ASA’s Ad Hoc Committee on the Brain Health Initiative, wrote in ASA Monitor, “Given this clear safety issue, anesthesiologists have an opportunity to lead in improving safety in an area that may not be ‘directly attributable to anesthesia’ but for which we can seriously impact on outcome.”  Although the AGS released a Clinical Practice Guideline for Postoperative Delirium in Older Adults in 2014, implementation of guidelines among practitioners is often slow, and this lag time leaves many patients vulnerable, Dr. Fleisher noted.  The Brain Health Initiative aims to accelerate the implementation of strategies among clinicians, including reducing or eliminating the use of drugs associated with POD.

Preoperative Screening

These strategies were among the topics of a session led by Dr. Fleisher at ANESTHESIOLOGY^® 2016.  According to one of Dr. Fleisher’s co-presenters, Deborah J. Culley, MD, of Brigham and Women’s Hospital, one of these approaches is screening older surgical patients for cognitive impairment before surgery.  Cognitive impairment at baseline is a predictor of POD, and POD is associated with poorer outcomes and increased mortality.  Further, the prevalence of cognitive impairment in older adults is substantial, with some studies showing cognitive impairment rates among community-dwelling older adults of roughly 20-30 percent.

This prevalence, along with POD’s association with morbidity and mortality, make brain health in the perioperative period an important consideration for anesthesia providers.  “What we see in the community is actually what’s going on in our perioperative patients,” Dr. Culley said.  “If the patient comes to us with some baseline cognitive impairment, the likelihood that they’re going to develop postoperative cognitive delirium is significantly enhanced.”  She also noted that “it’s difficult to find studies that don’t demonstrate that cognitive impairment is associated with greater mortality.”  POD not only increases the risk of adverse outcomes, but it also causes stress for the patient, family and caregivers, and adds greatly to the costs of hospitalization.²  “It’s really a large healthcare issue as we look at these older individuals who are progressively coming into our operative arenas,” she said.

“The problem is that we do a great job of evaluating almost every organ system ... But when we get to the point where we‘re thinking about a patient’s cognitive status, we really don’t know what’s going on,” Dr. Culley stressed.  To help fill this void, she and her colleagues use the Mini-Cog™, a screening tool that requires relatively little training, takes two or three minutes to administer and can be done in the preadmission testing center.  Regardless of the specific tool used, the important thing is to screen, because “you can’t look at that older surgical patient and identify that patient who is at risk,” she said.  “There are a lot of studies showing that healthcare professionals just cannot predict if someone has cognitive impairment.”

Intraoperative and Postoperative Care

Miles Berger, MD, PhD, of Duke University Medical School, who also presented at the ASA session, argued that, considering POD’s prevalence and the availability of geriatric medical bundles to address everything from respiratory complications, deep vein thromboses (DVT) and blood clots to nutritional depletion and pressure ulcers, the time has come for a comparable bundle to improve postoperative cognitive outcomes. (Dr. Berger co-authored an article in the June 2016 issue of ASA Monitor “ASA Brain Health Initiative:  The Science Behind the Scene.”)

He offered the following steps for anesthesiologists to reduce the risk of POD and delayed cognitive recovery:

Help the patient regain orientation after surgery.  Although many older surgical patients have no clinical history of dementia or cognitive impairment and can cope well at home with their family members, the unfamiliarity of the hospital setting, combined with the surgery and anesthesia, can precipitate POD.  Simple steps, such as telling the patient what time it is, making sure there’s a clock on the wall in the room, bringing a family member into the room, using whiteboards to write down the day of the week and the time the nurses will be coming in, and returning hearing aids and glasses can all make a huge difference for older patients. 

According to Dr. Fleisher, who was quoted in an article in the Penn Medicine News Blog, “Encouraging patients to follow a balanced diet and exercise regularly in the lead up to surgery, allowing patients to bring mementos and family photos to their hospital room after surgery, even asking families and caregivers to keep a close eye on small declines in patients’ cognitive function preoperatively—simple things like the patient not being as sharp as he or she once was—may help clinicians properly prepare for patient care, and may help patients readjust after surgery and avoid postoperative delirium. While these have not been scientifically proven to help, we think that even the smallest measures may make a difference for patients who are coming out of anesthesia.”

Assess the patient for fall risk.  “This is a major issue in older adults,” said Dr. Berger.  “In my own research, I’ve seen patients coming back with bandages on places where they didn’t have surgery, which was surprising to me, even though I wasn’t really studying that.  Falls came up as a major problem, even though I’m a cognitive researcher.” 

Build mobilization.  Movement and exercise can help older surgical patients by preventing DVT and providing the normal beneficial physical and cognitive effects of exercise.  Physical therapy and occupational therapy consults also can be helpful for patients who are having difficulty with mobility and transferring from the bed. 

Encourage good sleep hygiene.  Sleep quality can have a major impact on an older surgical patient’s postsurgical recovery.  According to Dr. Berger, a large body of research shows sleep disorders, such as obstructive sleep apnea, can interfere with the restorative effects of sleep on the central nervous system.  He suggests encouraging daytime sleep hygiene and a normal circadian clock, opening the blinds during the daytime, avoiding excessive napping, and a nighttime sleep protocol that includes keeping noise to a minimum, no television and dimming the hall lights.  “In the hospital, we do things that are best for the provider,” he said.  Physicians often want to round early in the morning, “which is great for us as doctors, but not so great for the patient.”

Optimize pain control using nerve blockade when possible.  Dr. Berger noted that untreated pain can cause delirium; however, excessive sedative and narcotic use also can predispose the patient to delirium and other problems, such as respiratory depression.  “It makes sense to use a regional blockade whenever possible and to use opioids, but in the lowest effective dose,” he said.  He also suggests using a pain assessment tool regularly and titrating medication appropriately. 

“This is all second nature for us as anesthesiologists.  More so perhaps than any other group of physicians, we’re used to titrating drugs to clinical events in real time,” he said. 

Avoid high-risk medications.  Benadryl has anticholinergic effects that have been shown in many studies to increase the risk of delirium.  Although the drug has anti-emetic effects, other anti-emetic drugs, such as Zofran, do not tend to cause delirium and offer a better first-line agent.  Xanax and some of the muscle relaxants can have postoperative deliriogenic effects as well.  In addition, preoperative midazolam, which is routinely given, can increase the risk of POD, according to some studies.  “I think we have to ask ourselves, are we doing things because this is how we do it—because this is what’s best for us as physicians—or because this is what’s best for the patient,” he said. 

The perioperative period offers anesthesiologists a good opportunity to review patients’ medication lists.  Streamlining the medication list can be helpful in prevention.  Do they really need to be on this medicine?  Is the patient not sure why they have to be on it?  Is it something their physician prescribed for them a long time ago?  Data is also accumulating that excessive sedation in the OR can have a detrimental cognitive effect postoperatively.  These new findings represent a paradigm shift of sorts for anesthesiologists, many of whom were taught that the effects of an inhaled agent disappear when the agent is turned off.  “We know more and more that’s not really true,” said Dr. Berger.

An ASA Monitor article by Stacie Deiner, MS, MD, and Michelle L. Humeidan, MD, PhD, on POD notes the AGS guideline that “the use of antipsychotics should be reserved for only the most severely agitated patients who pose a risk to themselves and others.”  (The article also provides additional information on medications known to contribute to cognitive dysfunction.)

Based on this presentation, there is a great deal anesthesiologists can do to reduce the incidence of POD in their older surgical patients.  We hope these strategies give you some ideas for your own practices.

With best wishes,

Tony Mira
President and CEO

References
¹ National Hospital Discharge Survey: 2007 summary.
Hall MJ, DeFrances CJ, Williams SN, Golosinskiy A, Schwartzman A
Natl Health Stat Report. 2010 Oct 26; (29):1-20, 24.

² The elderly surgical patient and postoperative delirium.
Demeure MJ, Fain MJ
J Am Coll Surg. 2006 Nov; 203(5):752-7.