Incidence and perioperative risk factors for postoperative delirium in the intensive care unit among adult surgical patients - Retrospective cohort study.

BACKGROUND AND AIMS

Postoperative delirium (POD) is a transient but serious complication that affects cognition and recovery. It may develop immediately after anaesthesia or following an otherwise uneventful emergence. As POD is associated with increased mortality and prolonged hospitalisation, identifying perioperative risk factors is essential. This study aimed to evaluate anaesthetic factors influencing POD during postoperative intensive care unit (ICU) stay.

METHODS

After ethics approval, we retrospectively reviewed ICU-admitted patients who underwent propofol- or desflurane-based general anaesthesia between January and December 2020. Patients who were intentionally sedated or mechanically ventilated postoperatively were excluded. Of 1,040 eligible patients, the POD was assessed using the Confusion Assessment Method for the ICU. Patients were classified into POD and non-POD groups. Demographics, surgical variables, and anaesthetic factors were compared using the Chi-square test, goodness-of-fit test, and Student's -test. Multivariate logistic regression was used to identify significant risk factors ( < 0.05).

RESULTS

POD occurred in 43 patients (4.1%). Affected patients were older, in poorer preoperative health, and had longer anaesthesia and surgery times. Univariate analysis showed associations between POD and age, American society of Anesthesiologists-Physical Status (ASA-PS), dementia, surgery duration, and intraoperative tracheostomy. Multivariate analysis identified age, ASA-PS, surgical site, anaesthesia time, and tracheostomy as independent predictors.

CONCLUSION

Prolonged anaesthesia was found to be a modifiable risk factor for POD. Identifying at-risk patients and minimising anaesthesia time may help reduce POD incidence. Persistent delirium beyond 72 hours postoperatively warrants further evaluation.