Most anesthesiologists are aware of the ASA Perioperative Brain Health initiative (PBHI) ( and its goals to increase awareness of perioperative delirium and perioperative neurocognitive disorders (PND) and to promote action to reduce the incidence of these conditions. The number of papers published on delirium and PND in scientific journals, as well as guidelines and systematic reviews, increases year on year. A recent important paper in JAMA Surgery drew attention to the economic impact of delirium and, consequently, made the business case for more investment and preventative action (JAMA Surg 2021;156:430-42). An accompanying editorial stated, “postoperative delirium is the single most compelling case for our national surgical community to address, through initiating hospital-based quality improvement programs” (JAMA Surg 2021;156:470-1). The authors of the editorial went on to make the central points, also stressed by the PBHI, that delirium is the commonest postoperative complication in older surgical patients and is associated with poorer outcomes, including increased complications, loss of independence, readmissions, and mortality.

Note that the JAMA Surgery editorial did not call for more research, although that, of course, is always essential, but instead for hospital-based quality improvement. In medicine, we know that despite guidelines and systematic reviews on best practice, there is a major gap between knowledge and action. The PBHI and the ASA Committee on Geriatric Anesthesia surveyed U.S. anesthesiologists and found that evidence-based actions for the prevention and detection of delirium were often not carried out; for example, formal postoperative screening for delirium in at-risk patients occurred routinely only about 20% of the time in academic medical centers and less than 10% of the time in all other types of practices (Perioper Med (Lond) 2020;9:6). While there is much more to be learned in the field of perioperative brain health, there are already established practical actions that can help reduce the incidence of delirium and PND, and yet those actions are not reliably carried out. Not all delirium is avoidable, but it is estimated that we can prevent 40% of cases. Moreover, early detection and mitigation are vital as studies show that the longer a patient remains delirious the greater the harm.

How then do we turn our knowledge into action? The first requirement is clear, evidence-based practices. Information is available in recent papers such as the “Best Practices for Postoperative Brain Health” from the International Perioperative Neurotoxicity Working Group (Anesth Analg 2018;127:1406-13), the American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Postoperative Delirium Prevention (Anesth Analg 2020;130:1572-90), and an expert consensus review from an ASA perioperative brain health expert panel (Br J Anaesth 2021;126:423-32). The latter paper, published in The BJA in January 2021, takes a pragmatic approach, distilling key actions not from a review of the scientific literature, but from existing published guidelines. The expert panel reached consensus on a small number of actions based not only on the strength of the evidence but also on potential impact and feasibility for widespread implementation. The six actions were:

  • Education and training for the multidisciplinary care team on detection and prevention of delirium and PND

  • Routine, simple preoperative cognitive screening to detect at-risk patients

  • Delirium screening

  • Nonpharmacologic interventions such as return of hearing aids and promoting the presence of family

  • Optimal pain control

  • Avoidance of antipsychotics and anxiolytics unless absolutely necessary.

Anesthesiologists are well placed to act as key members of the multidisciplinary perioperative team to partner and lead with surgeons on joint quality improvement initiatives. The goal of such initiatives should be to ensure that processes of care to improve perioperative brain health become part of routine management for all older surgical patients.

A key component of any quality improvement initiative is understanding the problem. One of the first things hospital teams can do is to measure both the incidence of preoperative cognitive impairment and the incidence of postoperative delirium and PND (Br J Anaesth 2016;117:145-8). Administrative data captures delirium poorly, and incidence tends to go up during research projects where teams are proactively and carefully screening patients on a regular basis. Record review using surrogate markers such as use of antipsychotics may help identify cases that might otherwise be missed. Having an idea of the baseline extent of the problem provides a platform on which to launch an improvement program. For example, establishing our preoperative cognitive screening program at Keck Medicine of USC in Los Angeles allowed us to demonstrate that about 25% of our surgical inpatients over 65 years showed some degree of cognitive impairment with Mini-Cog testing (J Am Geriatr Soc 2020;68:2359-64). This data stimulated conversation with the wider perioperative team, including not only surgeons but also nurses, pharmacists, geriatricians, therapists, and the IT team, to build a pathway to detect at-risk patients, communicate that risk, take actions such as reducing benzodiazepine prescription, and create alerts within the EHR to flag patients who require close observation (Figure). With a true QI approach, each step of the pathway requires testing and refining before final implementation. Programs such as the Hospital Elder Life Program (HELP) developed by Sharon Inouye at Harvard have shown that simple, practical actions can reduce the incidence of delirium, and when applied to surgical patients, modified HELP programs have not only reduced delirium but also the incidence of other complications and length of stay and promoted a faster return to normal activities of daily living (N Engl J Med 1999;340:669-76; JAMA Intern Med 2020;180:17-25).

Anesthesiologists have rightly focused on whether the type of anesthetic given or the use of intraoperative processed EEG monitoring can reduce the incidence of delirium and PND. However, at present there are no clear answers, and these topics remain the subjects of ongoing research. In contrast, there are simple steps in the perioperative pathway (some of which have been highlighted above) and others, such as avoidance of drugs on the Beers criteria list, that have established evidence behind them (Anesth Analg 2018;127:1406-13; Anesth Analg 2020;130:1572-90; Br J Anaesth 2021;126:423-32). In addition, there is growing evidence that frailty and delirium are closely linked, and screening for frailty and delirium should become a routine part of preoperative assessment (Anesthesiology 2020;133:1164-6). A frailty screening kit designed by members of the ASA Committee of Geriatric Anesthesia will be available soon on the ASA website. There are national QI initiatives such as the Age-Friendly Health Systems Initiative, which aims to improve care for hospitalized older people, and improvement work on perioperative delirium and PND fits well into the mentation and medication pillars of this initiative ( Involving patients and families in the design of a perioperative brain health pathway is also likely to increase success, as ideas can be tested and feedback elicited from the individuals who have the most to gain from improvement, and the most to lose from an episode of delirium or PND.

Despite multiple best practice guidelines, systematic reviews, and recent summaries of key actions, simple, evidence-based steps that can help reduce the incidence of delirium and PND are not always taken. Anesthesiologists as key members of the multidisciplinary perioperative team are well placed to lead, or partner with surgical colleagues, on quality improvement programs to reduce delirium and PND. Through implementation of evidence-based perioperative care pathways to protect the brain health of older surgical patients, we can turn knowledge into action.

Disclosure: Dr. Peden is an advisory board member and shareholder of Somnus Scientific.