E.SEET1, L.K.TI2, C.T.Y.CHUA2, S.T.H.CHEW3, Y.H.KE4, V.Q.Y.LIM5, W.Y.WONG5, J.B.ZHANG5, B.LIM5, H.J.NEO2, W.LOH2
Khoo Teck Puat Hospital1, National University Hospital2, Singapore General Hospital3, MOH Holdings Pte Ltd (MOHH)4, Tan Tock Seng Hospital5
Postoperative delirium is common yet under-diagnosed and potentially preventable. It contributes to perioperative complications in the elderly and has significant long-term effects on patient independence and quality-of-life. In this multicentre prospective cohort study, we investigated the incidence, risk factors and sequelae of postoperative delirium in elderly patients undergoing major non-cardiac surgery.
Elderly patients were consented from NUHS, KTPH, SGH and TTSH after DSRB ethics approval (2019/00703). Inclusion criteria were patients aged ≥65 years scheduled to undergo major non-cardiac surgery (defined as surgery ≥2hrs in duration and requiring ≥1 day hospital stay). Baseline demographic data, comorbidities, smoking/alcohol use, medication history, investigations and perioperative data were analysed as independent variables. Patients were surveyed for their baseline cognition status (Montreal Cognitive Assessment), Brief Psychiatric Rating Scale and Patient Health Questionaire (PHQ-9). After surgery, patients will be assessed in the Recovery Unit for delirium 30-60min after arrival using the Nursing Delirium Screening Scale (NuDESC).
98 patients completed the study with 11.2% having postoperative delirium. Univariate analysis identified increasing age (74.6±3.2 vs. 70.6±4.4,p=0.005), higher ASA3 physical status (63.6% vs. 31.0%,p=0.019), raised Cr (86.4±25.0 vs. 71.9±22.0,p=0.046), raised HbA1c (7.8%±1.2 vs. 6.6%±0.9,p=0.011), higher PHQ-9 scores (p=0.031), and postoperative hypotension (18.2% vs 1.2%,p=0.033) as risk factors. Postoperative delirium was associated with longer hospital length of stay (8 vs. 4 days,p=0.049).
Postoperative delirium is common in vulnerable elderly patients presenting for major surgery. Modifiable risk factors identified in this study can potentially be targeted to reduce its incidence. This may impact hospital resource utilisation and the patients’ quality-of-life post-surgery.