Association of cervical atherosclerosis on Doppler ultrasonography and postoperative delirium in patients undergoing spinal surgery: a single-center, retrospective, observational study

Purpose This study aimed to evaluate the association between cervical atherosclerosis on Doppler ultrasonography and postoperative delirium (POD) in patients undergoing spinal surgery. Methods In this retrospective observational study using prospectively collected data, 295 consecutive patients aged > 50 years underwent spine surgery at a single institution between March 2015 and February 2021. Cervical atherosclerosis was defined as the intima-media thickness (IMT) of the common carotid artery (CCA) being ≥ 1.1 mm on pulsed-wave Doppler ultrasonography. Univariate and multivariate logistic regression analyses were performed with the prevalence of postoperative delirium as a dependent variable. Age, sex, body mass index, medical history, American Society of Anesthesiologists Physical Status (ASA-PS), CHADS2 score (an assessment score for stroke), instrumentation, duration of surgery, blood loss, and cervical arteriosclerosis were the independent variables. Results Twenty-seven patients of 295 (9.2%) developed delirium postoperatively. Forty-one (13.9%) of the 295 patients had cervical atherosclerosis. Their univariate analyses showed that age ( P = 0.001), hypertension ( P = 0.016), cancer ( P = 0.046), antiplatelet agent use ( P < 0.001), ASA-PS ≥ 3 ( P < 0.001), CHADS2 score ( P < 0.001), cervical atherosclerosis ( P = 0.008), and right CCA-IMT ( P = 0.007) were significantly associated with POD. However, multivariate logistic regression analyses showed older age (odds ratio [OR], 1.109; 95% confidence interval [CI] 1.035–1.188; P = 0.03) and antiplatelet agent use (OR, 3.472; 95% CI 1.221–9.870; P = 0.020) to be significantly associated with POD. Conclusions There was a significant association between POD and the prevalence of cervical atherosclerosis using the univariate logistic regression analysis. Furthermore, multivariate logistic regression analyses showed that older age and antiplatelet agent use were independently associated with POD.