Associated risk facators of postoperative delirium after spine surgery in midaged and elderly

Abstract

Objective Analyzed various risk factors for postoperative delirium after spine surgery in the mid-aged and elderly. Methods Between January 2010 and August 2015, a total of 451 patients (226 males and 225 females) with an average age of (65.1±18.3) years (range 45-84 years) and who underwent spinal surgery in Chinese-Japanese Friendship Hospital were reviewed retrospectively, and patients with central nerve system disease or psychiatric disorders were excluded in study. All patients underwent the surgical procedures including fusion operation, decompressive laminectomy and discectomy of the lumbar spine, anterior cervical discectomy and fusion, laminoplasty and foraminotomy of the cervical spine. Cognition tests such as Clinical Dementia Rating (CDR) and Global Deterioration Scale (GDS) were used to evaluate delirium, and all patients were subgrouped into delirium group and non-delirium group. Preoperative factors included age, education level, drug treatment, BMI index, alcohol use, comorbid diseases, surgical history, surgical site, systolic blood pressure (SBP), hemoglobin (HGB), hematocrit (HCT), and blood biochemistry indexes, intraoperative factors including operative time, blood loss, blood transfusion, use of surgical implants, times of intraoperative hypotension <80 mmHg and use of fentanyl, propofol and dezocine. PASW Statistics 18.0 software were used for statistical analysis of the difference between 2 groups, and logistic regression analysis was used for determining the risk factors. Results There were 42 (9.31%) patients in delirium group. 31 cases were diagnosed on the first postoperative day, while 11 on the second postoperative day. The average age of the patients in delirium group was 66.3±14.4 years, the male/female ratio was 1∶ 1.1 (20∶22). The average age in non-delirium group was 66.7±15.5 years, and the male /female ratio was 1.01∶1 (206∶203). Intraoperative hypotension and dosage of dezocine had significant differences between the two groups, and they were both independent risk factor of postoperative delirium. The multiple regression equation is Y=-0.11+0.02X0+0.21X1, X0 was amount of dezocine, X1 was times of intraoperative hypotension. The risk coefficient was 0.43. Conclusion Frequency of intraoperative hypotension and dosage of dezocine are both independent risk factor of postoperative delirium after spine surgery in the mid-aged and elderly patients, we need to pay attention to maintain intraoperative blood pressure stability, and use dezocine in caution, in order to reduce the incidence of postoperative delirium. Key words: Delirium; Spinal diseases; Hypotension; Risk factors