The effect of preoperative cognitive impairment and type of vascular surgery procedure on postoperative delirium with associated cost implications

Objective Postoperative delirium (POD) has a high prevalence among vascular surgery patients, increasing morbidity, mortality, and length of stay. We prospectively studied preoperative risk factors for delirium that can be assessed by the surgical team to identify high-risk patients and assessed its impact on hospital costs. Methods There were 173 elective vascular surgery patients assessed preoperatively for cognitive function using the Montreal Cognitive Assessment (MoCA) and the Confusion Assessment Method for POD, which was verified by chart and clinical review. Demographic information, medications, and a history of substance abuse, psychiatric disorders, and previous delirium were prospectively recorded. An accompanying retrospective chart review of an additional 434 (elective and emergency) vascular surgery patients provided supplemental cost information related to sitter use and prolonged hospitalization secondary to three factors: delirium alone, dementia alone, and delirium and dementia. Results Prospective screening of 173 patients (73.4% male; age, 69.9 ± 10.97 years) identified that 119 (68.8%) had MoCA scores 200 hours (8.3 days), accounting for 69.7% of sitter costs for the surgical unit; 43.7% of costs were accounted for by patients with pre-existing cognitive impairment. Conclusions POD is predicted by type of vascular surgery procedure, impaired cognition (MoCA), and previous delirium. Costs and morbidity related to delirium are greatest for those with impaired cognitive burden. Preoperative MoCA screening can identify those at highest risk, allowing procedure modification and informed care.