Incidence and risk factors of delirium in post-anaesthesia care unit

Abstract

Introduction: Post-anaesthesia care unit (PACU) delirium is a potentially preventable condition that results in a significant long-term effect. In a multicentre prospective cohort study, we investigate the incidence and risk factors of postoperative delirium in elderly patients undergoing major non-cardiac surgery. Methods: Patients were consented and recruited from 4 major hospitals in Singapore. Research ethics approval was obtained. Patients older than 65 years undergoing non-cardiac surgery >2 hours were recruited. Baseline perioperative data were collected. Preoperative baseline cognition was obtained. Patients were assessed in the post-anaesthesia care unit for delirium 30–60 minutes after arrival using the Nursing Delirium Screening Scale (Nu-DESC). Results: Ninety-eight patients completed the study. Eleven patients (11.2%) had postoperative delirium. Patients who had PACU delirium were older (74.6±3.2 versus 70.6±4.4 years, P=0.005). Univariate analysis showed those who had PACU delirium are more likely to be ASA 3 (63.6% vs 31.0%, P=0.019), had estimated glomerular filtration rate (eGFR) of <60mL/min/1.73m2 (36.4% vs 10.6%, P=0.013), higher HbA1C value (7.8±1.2 vs 6.6±0.9, P=0.011), raised random blood glucose (10.0±5.0mmol/L vs 6.5±2.4mmol/L, P=0.0066), and moderate-severe depression (18.2% vs 1.1%, P=0.033). They are more likely to stay longer in hospital (median 8 days [range 4–18] vs 4 days [range 2–8], P=0.049). Raised random blood glucose is independently associated with increased PACU delirium on multivariate analysis. Conclusion: PACU delirium is common in elderly patients with risks factors presenting for major surgery. Keywords: Geriatrics, major non-cardiac surgery, postoperative delirium

Abnormal cortical activity in postoperative delirium based on EEG microstate: a cross-sectional study

“…In the clinical setting, it has been observed that intraoperative hyperglycemia is an independent risk factor for delirium in elderly patients. Ke et al conducted a study and found that higher randomized blood glucose levels (> 9.5 mmol/L) were positively associated with delirium in the post-anesthesia care unit, as determined by multivariate analysis [50]. Moreover, previous research has shown a signi cant association between the duration of intraoperative hyperglycemia (blood glucose > 8.3 mmol/L) and postoperative delirium [14].…”

Effects of qCON and qNOX-guided general anaesthesia management on patient opioid use and prognosis: a study protocol

“… 37 Recent studies have shown that older patients have a higher incidence of delirium in the PACU after surgery. 38 Therefore, early assessment, appropriate intervention, and prevention are necessary to reduce medical costs and improve the quality of life after surgery. To achieve this goal, this trial will plan to evaluate patients for delirium using the Nu-DESC tool in the postoperative PACU and on days 1 and 2 after surgery.…”

“…The Nursing Delirium Screening Scale (Nu-DESC) tool is a highly sensitive and specific instrument for screening postoperative delirium, including symptoms such as disorientation, behavioural abnormalities, communication disorders, hallucinations or delusions, psychomotor retardation, and other related symptoms 37. Recent studies have shown that older patients have a higher incidence of delirium in the PACU after surgery 38. Therefore, early assessment, appropriate intervention, and prevention are necessary to reduce medical costs and improve the quality of life after surgery.…”

Anaesthesia and delirium: a Mendelian randomization study

“…Clinical research suggests a significant link between anaesthesia and delirium 11,12 . However, due to confounding factors such as age, anaemia, medication, and others, the causal relationship between anaesthesia and delirium remains unclear 13 . Moreover, limited studies have explored the impacts of different anaesthetic methods on delirium risk.…”