Perioperative care of the elderly patient: An update*
ABSTRACT
Elderly patients pose unique challenges perioperatively. They are more likely than younger surgical patients to be mentally and physically compromised at baseline, which increases the risk of delirium and postoperative cognitive dysfunction. Postoperative cognitive risk can be predicted, however, and effective strategies exist to reduce this risk. Elderly patients are also at increased risk of a precipitous postoperative decline in physiologic reserve, which can lead to organ failure. General recommendations for the perioperative care of elderly patients include avoiding drugs that raise the risk of delirium, ensuring adequate caloric and fluid intake, getting the patient out of bed and into physical therapy as soon as possible, and early planning for discharge. An elderly patient’s postoperative cognitive risk and its impact on quality of life should be factored into the decision whether to undergo surgery. Family conferences are recommended to address the many questions and challenges that surgery in an elderly person can pose.
KEY POINTS
- Postoperative cognitive dysfunction and delirium are distinct conditions, though both are common in the elderly. Postoperative cognitive dysfunction may persist for weeks to months and may not be obvious, whereas delirium, a disorder of attention and cognition, is easier to detect clinically.
- Major predictors of postoperative delirium are severe illness, baseline dementia, dehydration, and sensory impairment.
- Drugs that raise dementia risk include anticholinergics, benzodiazepines, meperidine, tricyclic antidepressants, first-generation antihistamines, and high-dose H2-receptor blockers.
- Early performance of hip fracture surgery in the elderly (ie, within 24 hours of admission) has not been shown to lower mortality but appears to improve other outcomes.
- Identifying and managing frail elderly patients is important. Signs of frailty are minimal activity, generalized muscle weakness, slowed performance, fatigue, and weight loss.
DISCUSSION
Question from the audience: In our preoperative clinic, we are trying to intervene to reduce delirium and postoperative cognitive dysfunction. How can we quickly screen for the most important predictors and act to reduce the risk?
Dr. Palmer: The most important risk factor for delirium is age, which obviously can’t be changed. Ask patients about alcohol use and depression. Check on nutritional status and begin supplementation if indicated. Discontinue high-risk medications. Check on electrolytes and their state of hydration; ideally, an electrolyte imbalance can be corrected preoperatively. In addition, other than in patients with end-stage renal disease, try to keep the hemoglobin above 7.5 g/dL, which appears to be associated with better outcomes and less risk of delirium.
It’s also important to remind the family to bring in the patient’s visual aids, hearing devices, and cane or walker so that they’re available right after the operation.
Intraoperative factors that are important for preventing delirium include maintaining good blood pressure levels, giving supplemental oxygen, minimizing the time under general anesthesia, and using local anesthesia if possible.
Question from the audience: How strong is the evidence for using spinal anesthesia as opposed to general anesthesia in preventing postoperative cognitive dysfunction and delirium, especially in the setting of hip fracture repair?
Dr. Palmer: The evidence is fairly soft. For patients undergoing either hip or knee arthroplasty who were randomized to receive either spinal (or local) or general anesthesia, the risk of delirium was similar, but complications such as prolonged bed rest, pressure ulcers, and catheter-related urinary tract infections were somewhat reduced in the spinal/local group.14 The relative risk of developing postoperative cognitive dysfunction is unclear—no randomized controlled trials have been conducted to answer that question.
Question from the audience: How do you use antipsychotic drugs, especially with the concerns from epidemiologic studies about an increased risk of death?
Dr. Palmer: No antipsychotic agents, including haloperidol, have a specific Food and Drug Administration–approved indication for treating agitation, dementia, or delirium. In general, they should not be used without a clear indication. That said, the usual off-label use is for patients who are severely agitated and are at risk of harming themselves or others. In an ICU setting, where patients have multiple lines, the use of these agents can be considered for a very agitated patient. Alternatives exist, but antipsychotics like haloperidol have the advantage that they can be given in small increments very rapidly and achieve good control of severe agitation.
Antipsychotic agents should only be used with great caution and for the shortest duration needed. As delirium resolves, they should be tapered fairly rapidly over a few days and ideally should be discontinued by the time of hospital discharge.
None of the antipsychotic agents—including those in the first generation and the newer atypical agents—is free of this risk of increased mortality. The mechanism is not understood; it may be torsades de pointes or hypotension leading to stroke or sudden cardiac death.
Question from the audience: What is the most efficient way to assess cognitive and physical functioning preoperatively?
Dr. Palmer: There may be a documented history of dementia, or family members may tell you if there has been memory loss or some decline in the patient’s self-care abilities. For patients without dementia, you can ask them directly if they can perform basic activities of daily living, such as getting out of bed or dressing. To assess higher-level function, ask if they can manage their own medications, pay bills, or handle their finances. If not, they might have cognitive impairment and are at higher risk for postoperative delirium. These are rather sensitive measures. There are instruments to assess this more precisely, but few clinicians have time to use them.
Quick bedside tests can help assess for delirium postoperatively. We see if patients are “alert and oriented times three” (“Do you know who you are, where you are, and the date?”). We test for attention by asking them to repeat a random string of numbers spoken 1 second apart in monotone; people who are delirious and many patients with severe dementia can’t repeat more than three numbers. A patient who is alert and oriented, has a good attention span (more than three numbers in correct order), and has no history of dementia probably doesn’t have delirium or dementia.
For physical function, ask if they can walk, get out of bed to a chair, and ambulate. If they don’t give clear answers, observe them get out of bed or a chair, walk 10 feet, and return to bed. If they can do that with good balance, especially within 10 to 15 seconds, they probably have reasonably normal mobility and are at lower risk for postoperative complications such as falls with injury.
