Anesthetics and Postoperative Delirium in Elderly after Elective Surgery: A Retrospective Comparison between Sevoflurane and Propofol.

Background: Postoperative delirium (POD) in elderly subjects is an important health issue as it is associated with high morbidity and mortality. Anesthetic agents are associated factors for the development of POD. However, the results of previous studies are heterogeneous. The current work aimed to determine the incidence and associated factors of POD after sevoflurane or propofol general anesthesia.

Methods: This was a retrospective study, where data were collected from the medical records of 200 subjects scheduled for elective surgery under general anesthesia. One hundred received sevoflurane, and the other 100 received propofol. The collected data included patient characteristics and preoperative and operative data. In addition, POD and any complications developed after surgery are also included. Mean and standard deviation were used to summarize quantitative variables, while frequency and percentages were used to express categorical data. The independent sample's student test was used to compare two means, and Chi-Square was used to calculate associations between categorical parameters. Risk estimate was determined by calculation of odds ratios. P value<0.05 was considered significant.

Results: Operative time was significantly shorter in sevoflurane than in propofol groups (249.91±45.41 vs 264.60±45.78 minutes, respectively). Otherwise, no significant differences were recorded for preoperative and operative data. The incidence of POD was significantly higher after propofol than sevoflurane (30.0% vs 14.0%). The POD was significantly associated with higher ASA-class physical status, diabetes mellitus, and type of anesthetic agent. ASA-III was 34.1% and 10.3% in patients with delirium than without delirium. Diabetes recorded 65.9% for the group with delirium compared to 10.3% for those without delirium.

Conclusion: POD was higher after propofol than sevoflurane anesthesia. It is associated with ASA physical status, diabetes, and the type of anesthetic agent used.