Anesthesiologists have a critically important role that often occurs minutes before a patient is transported to the OR. An essential part of our preoperative visit is to engage the patient in the informed consent process. Informed consent is an ethical and legal obligation of anesthesiologists in the United States, and The Joint Commission requires documentation of the process. The required elements of informed consent include a discussion of the planned procedures, including the risks and benefits, reasonable alternatives and their risks and benefits, an assessment of the patient’s competence, understanding, and agreement, and documentation of the discussion. Because it is impossible to list every possible risk from a sore throat to death, we must decide which risks to disclose. In the U.S., states are split between applying a “physician-based standard” requiring the disclosure of risks that a reasonable medical practitioner would make under the same circumstances or a “patient-based standard” that discloses risks relevant to a reasonable patient in a similar situation (J Leg Med 2018;38:221-70).
Evidence suggests that patients want to learn the most common risks of anesthesia and surgery, and the more serious risks (Acta Anaesthesiol Scand 2013;57:342-9). As both a common and a serious potential complication, the risk of perioperative neurocognitive disorders (PNDs) is an essential part of the informed consent discussion for all older adults presenting for surgery and anesthesia (J Leg Med 2018;38:221-70). The surgical patient population is aging at a faster rate than the U.S. population, and these patients are at increased risk for complications due to the physiology of aging and the pathophysiology of geriatric syndromes. The most common postoperative complications in older adults include PND, including postoperative delirium, delayed neurocognitive recovery, and minor or major neurocognitive decline persisting up to 12 months after the procedure.
Several expert publications, such as Best Practices for Postoperative Brain Health and the American Geriatrics Society and American College of Surgeons (ACS) Best Practice Guidelines, recommend discussing the possibility of postoperative delirium with older surgical patients (Anesth Analg 2018;127:1406-13; J Am Coll Surg 2012;215:453-66). Given that the incidences of delirium (up to 50%, depending on the type of surgery) and postoperative neurocognitive decline (10%-20% at three months postoperatively) far outweigh the incidences of other complications that we routinely discuss with patients (chipped teeth, drug allergies, malignant hyperthermia, acute coronary syndrome, cerebrovascular accident, awareness under anesthesia, or mortality), we should include PND in our discussion with older patients. Not only is PND prevalent in older adults, it represents a serious risk. PNDs have been associated with a prolonged length of hospital stay, discharge to a nursing home, functional status decline, risk for subsequent dementia, and mortality. However, in a survey of ASA members, 30.5% of respondents “rarely” or “never” provide information preoperatively to older adults “regarding the risks of delirium or other cognitive disorder after surgery” (Periper Med 2020;9:6). Of the remaining respondents, only 25.5% said they provide this information preoperatively “usually” or “every time,” and 44% of respondents reported “frequently,” “sometimes,” or “occasionally” providing this information.
Ideally, these risk discussions should occur between surgeons and their patients at the time of the surgical decision and reinforced in the preoperative clinic visit (Anesth Analg 2018;126:629-31). This proactive discussion would facilitate shared decision-making, especially in the case of elective surgery, but even in the case of urgent surgery when different procedure types or treatments are available. The discussion of a patient’s risk for PND should occur as part of a larger discussion with patients according to the Age-Friendly Health Systems initiative with attention to the “4Ms” (What Matters, Medication, Mentation, Mobility) and identifying “What Matters” to each patient regarding health outcome goals and care preferences (ASA Monitor 2021;85:16-7). In that ideal scenario, patients would be able to decide whether the risk of undergoing surgery is aligned with their health goals. Then, anesthesiologists would simply reinforce these discussions in the preoperative holding area. Unfortunately, patients often hear about these potential complications for the first time on the morning of surgery. We recognize that this can be stressful for patients and also anesthesiologists. Research has advanced understanding of PND, and we know major risk factors for PND include age, education level, and pre-existing cognitive impairment. Though the exact etiology of PND is unclear, the systemic inflammatory response to the surgical procedure itself is an important contributor to PND. Anesthesia alone is unlikely to be a sole contributor (Anesth Analg 2022;134:389-99). Therefore, it is likely a combination of the patient’s pre-existing factors and perioperative factors that contribute to PND. Tools such as the ACS Risk Calculator have recently expanded to help physicians concretely discuss the geriatric risk for postoperative complications, including delirium, with older surgical patients and their families. The information available on layperson websites such as AARP (asamonitor.pub/3GN0fHT) and the ASA Perioperative Brain Health Initiative website can provide additional context for patients and families (asahq.org/brainhealthinitiative/toolsforpatients).
We encourage you to reflect upon whether your consent discussions could be more truly informative. Given the current state of knowledge about the incidence and risk of PND, we recommend that anesthesiologists provide older patients with a description of PNDs using plain language such as the definitions provided on the ASA Perioperative Brain Health Initiative website (asahq.org/brainhealthinitiative/toolsforpatients/definitions). We encourage a patient-specific discussion of individual risk based on well-established factors such as the patient’s age and preoperative cognitive and frailty status. Validated tools to screen for cognitive and frailty status can be quickly employed preoperatively, and a calculator such as the ACS Risk Calculator with geriatric outcomes can help guide the conversation (Anesth Analg April 2021). If a caregiver is present, it is pertinent to discuss conservative preventive measures, including frequent re-orientation, provision of assistive devices (hearing aids, glasses, mobility devices), visits with loved ones, encouraging sleep hygiene and early mobility, and providing clocks, calendars, and photos. The importance of family engagement can be stressed to the family members present for the discussion. Informed by the knowledge of PND risk, patients and families can decide to reserve important decision-making or cognitively demanding activities (e.g., signing legal documents, estate planning) until several months after surgery. These preoperative discussions will enable patients and their caregivers to have realistic expectations for the postoperative course of recovery. It will also prepare family members and caregivers for the possibility of witnessing their loved one in a delirious state and contextualize what can otherwise be an alarming experience.