Associations of postoperative delirium with activities of daily living in older people after major surgery: A prospective cohort study

Aims: To assess the association of postoperative delirium developed in the post-anaesthetic care unit (PACU) with older patients' ability to perform activities of daily living (ADL) during the first five postoperative days. Background: Previous studies have focused on the association between postoperative delirium and long-term function decline, however the association between postoperative delirium and the ability to perform ADL, particularly in the immediate postoperative period, needs further investigation. Design: A prospective cohort study. Methods: A total of 271 older patients who underwent elective or emergency surgery at a tertiary care hospital in Victoria, Australia, participated in the study. Data were collected between July 2021 and December 2021. Delirium was assessed using the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5). The Katz Index of Independence in Activities of Daily Living (KATZ ADL) scale was used to measure ADL. ADL was assessed preoperatively and daily during the first five postoperative days. The STROBE checklist was used to report this study. Results: Results showed that 44 (16.2%) patients developed new episode of delirium. Postoperative delirium was independently associated with decline in ADL (RR = 2.83, 95% CI = 2.71–2.97; p < 0.001). Conclusions: Postoperative delirium was associated with a decline in ADL among older people during the first five postoperative days. Screening for delirium in the PACU is essential to identify delirium during the early stages of postoperative period and implement a timely comprehensive plan. Relevance to clinical practice: Delirium assessment of older patients in the PACU, and for at least the first five postoperative days, is strongly recommended. We also recommend engagement of patients in a focused physical and cognitive daily activity plan, particularly for older patients undergoing major surgery. Patient or public contribution: Patients and nurses helped in data collection at a tertiary care hospital.