Post-operative Cognitive Decline After Ambulatory Cataract Surgery in the Elderly Population

Postoperative cognitive decline (POCD), now classified within the spectrum of perioperative neurocognitive disorders, is characterized by a decline in cognitive function following anesthesia and surgery. Although POCD has been extensively studied following major cardiac and non-cardiac procedures, limited evidence exists regarding cognitive outcomes after ambulatory procedures performed under sedation. Cataract surgery represents one of the most common surgical procedures in older adults, a population with a high prevalence of comorbidities associated with cognitive vulnerability. Despite this, postoperative cognitive outcomes following ambulatory cataract surgery remain poorly characterized.

This prospective, single-center, observational study is designed to estimate the proportion of elderly patients who develop postoperative cognitive decline following ambulatory cataract surgery performed under sedation at the Kensington Eye Institute. The study will not alter routine clinical care or anesthetic management. Participants will undergo standard perioperative care, and all anesthetic techniques, medications, and perioperative management will be determined by the treating anesthesia and surgical teams according to routine clinical practice.

Following informed consent, participants will complete a baseline cognitive assessment using the Tele-Montreal Cognitive Assessment (T-MoCA), a validated cognitive screening instrument suitable for remote administration. Demographic information, relevant medical comorbidities, home medications, and perioperative anesthetic and procedural data will also be collected. Follow-up cognitive assessments will be completed remotely using the T-MoCA at approximately 3 weeks and 3 months after surgery through secure electronic access.

The study will evaluate cognitive change by comparing follow-up T-MoCA scores with baseline performance. Postoperative cognitive decline will be defined according to a prespecified threshold based on change from baseline. In addition to estimating the incidence of postoperative cognitive decline, the study will describe the prevalence of previously unrecognized baseline cognitive impairment identified during preoperative cognitive screening.

Data will be collected using REDCap, a secure, web-based electronic data capture system. Study data will be de-identified using unique participant identification numbers, and identifiable information will be stored separately from research data in accordance with institutional privacy policies. Data quality will be maintained through standardized data collection procedures, source document verification, and routine review for completeness and accuracy.

Descriptive statistical methods will be used to estimate the proportion of participants meeting criteria for postoperative cognitive decline at each follow-up time point. The planned sample size of approximately 300 participants provides adequate precision for estimating the incidence of postoperative cognitive decline while accounting for anticipated loss to follow-up.

Inclusion criteria

• All patients ages 65 and older

Exclusion criteria

• Inability to understand instructions in English
• Lack of access to a computer, tablet, smartphone, or internet access
• Patients with established cognitive deficit diagnoses (e.g. Alzheimer's, TBI, stroke)
• Patients with known psychiatric diagnoses
• Patients who have undergone any procedure or surgery requiring sedation, regional, neuraxial or general anesthesia within the past 6 months