Age-Related Perioperative Neurocognitive Disorders: Experimental Models and Druggable Targets.

With the worldwide increase in life span, surgical patients are becoming older and have a greater propensity for postoperative cognitive impairment, either new onset or through deterioration of an existing condition; in both conditions, knowledge of the patient's preoperative cognitive function and postoperative cognitive trajectory is imperative. We describe the clinical utility of a tablet-based technique for rapid assessment of the memory and attentiveness domains required for executive function. The pathogenic mechanisms for perioperative neurocognitive disorders have been investigated in animal models in which excessive and/or prolonged postoperative neuroinflammation has emerged as a likely contender. The cellular and molecular species involved in postoperative neuroinflammation are the putative targets for future therapeutic interventions that are efficacious and do not interfere with the surgical patient's healing process.

Improving perioperative brain health: an expert consensus review of key actions for the perioperative care team.

Delirium and postoperative neurocognitive disorder are the commonest perioperative complications in patients more than 65 yr of age. However, data suggest that we often fail to screen patients for preoperative cognitive impairment, to warn patients and families of risk, and to take preventive measures to reduce the incidence of perioperative neurocognitive disorders. As part of the American Society of Anesthesiologists (ASA) Perioperative Brain Health Initiative, an international group of experts was invited to review published best practice statements and guidelines. The expert group aimed to achieve consensus on a small number of practical recommendations that could be implemented by anaesthetists and their partners to reduce the incidence of perioperative neurocognitive disorders. Six statements were selected based not only on the strength of the evidence, but also on the potential for impact and the feasibility of widespread implementation. The actions focus on education, cognitive and delirium screening, non-pharmacologic interventions, pain control, and avoidance of antipsychotics. Strategies for effective implementation are discussed. Anaesthetists should be key members of multidisciplinary perioperative care teams to implement these recommendations.

State of the clinical science of perioperative brain health: report from the American Society of Anesthesiologists Brain Health Initiative Summit 2018.

Cognitive recovery after anaesthesia and surgery is a concern for older adults, their families, and caregivers. Reports of patients who were 'never the same' prompted a scientific inquiry into the nature of what patients have experienced. In June 2018, the ASA Brain Health Initiative held a summit to discuss the state of the science on perioperative cognition, and to create an implementation plan for patients and providers leveraging the current evidence. This group included representatives from the AARP (formerly the American Association of Retired Persons), American College of Surgeons, American Heart Association, and Alzheimer's Association Perioperative Cognition and Delirium Professional Interest Area. This paper summarises the state of the relevant clinical science, including risk factors, identification and diagnosis, prognosis, disparities, outcomes, and treatment of perioperative neurocognitive disorders. Finally, we discuss gaps in current knowledge with suggestions for future directions and opportunities for clinical and translational projects.

Cognitive status predicts preoperative instruction compliance.

The most common postoperative complication for older adults is perioperative neurocognitive disorder (PNCD). Its greatest risk factor is preoperative cognitive impairment. Cognitive impairment also predicts higher likelihood of postoperative complications. While the cause of disparity in outcomes is likely multifactorial, the ability to correctly follow perioperative instructions may be one modifiable component. The purpose of this study was to determine whether cognitive impairment led to reduced preoperative instruction compliance and if so, identify barriers and enact a tailored care-plan to close the gap. Our preoperative clinic implemented routine Mini-Cog screening to identify older (age ≥ 65) surgical patients at increased risk. All patients received the same instructions and, on day of surgery, were surveyed to determine correct execution of nil per os guidelines, chlorhexidine wipe use and medication management. Data was stratified by cognitive status to evaluate whether impairment predicted instruction execution. Feedback from patients and families were compiled. Of those who screened negative for impairment, 68% correctly followed instructions, while 84.2% of those impaired struggled with ≥1 instruction(s); impaired patients were more likely to incorrectly follow instructions (OR = 10.5, p-value = 0.001). Areas for change were identified and team-based solutions were enacted with additional support for those with impairment. We found a clear difference in correct execution with respect to cognitive status. By improving instructions as an institution and adding additional support for those with impairment, the compliance gap was significantly reduced. Targeting perioperative instructions and tailoring care in this population may be one modifiable component in the outcome disparity they face.

Beyond Cognitive Screening: Establishing an Interprofessional Perioperative Brain Health Initiative.

OBJECTIVE: Perioperative neurocognitive disorder (PND) is now recognized as the most common postoperative complication in older surgical patients. Current multidisciplinary guidelines recommend simple cognitive screening of older adults before surgery. Patients identified at risk should have input from an interprofessional team with expertise caring for older surgical patients. Data suggest these recommendations are infrequently met. We set out to test feasibility of routine cognitive screening in a busy preoperative assessment clinic and establish a perioperative pathway with multidisciplinary support for patients identified at risk. METHODS: We undertook a prospective quality improvement study. A cohort of 1,803 older surgical patients scheduled for preoperative evaluation was screened with the Mini-Cog© test. As the project developed, we began confirmatory neurocognitive testing by occupational therapists for those patients flagged at risk. Patients confirmed at risk were referred for further evaluation by a geriatrician and geriatric pharmacist. Alerts were developed to flag patients at risk through their in-patient journey, and a multidisciplinary team developed a comprehensive care pathway. RESULTS: We demonstrated that implementing routine cognitive screening can be done in a busy clinic, regardless of prior experience. The prevalence of preoperative cognitive impairment was 21% in our older patients undergoing inpatient surgery, rising to 36% in those older than 85 years. When the Mini-Cog results were not known to providers, they were unable to identify cognitive impairment in half of the patients, supporting the use of a validated screening test. We established an interprofessional team and pooled relevant recommendations into an age-friendly perioperative care pathway for patients at increased cognitive risk. CONCLUSION: Cognitive screening must be done to reliably identify older surgical patients at risk of PND. Demonstrating the prevalence of cognitive impairment in older surgical patients can provide impetus to develop a multidisciplinary team and care pathway with the aim of reducing the incidence of PNDs. J Am Geriatr Soc 68:2359-2364, 2020.