[Postoperative delirium is associated with cognitive dysfunction one week after coronary artery bypass grafting surgery].

OBJECTIVE: To investigate the relationship between postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) after coronary artery bypass graft in Chinese population. METHODS: One hundred and seven patients who were referred for elective coronary artery bypass grafting (CABG) surgery were enrolled in this prospective cohort study. Baseline and perioperative variables as well as occurrence of postoperative complications were recorded. POD was diagnosed using the Confusion Assessment Method for the Intensive Care Unit twice daily during the first seven postoperative days. A neuropsychological test battery that included 7 tests with 9 subscales was administered at baseline and on the seventh day after surgery. POCD was defined using the same definition that was used in the ISPOCD1 study. RESULTS: The incidence of POD was 47.7% (51/107) while that of POCD was 55.3% (57/103). Multivariate Logistic regression analyses identified four independent risk factors of POD, i.e., increasing age (OR 1.174, 95% CI 1.085-1.269, P<0.001), preoperative history of diabetes mellitus (OR 4.224, 95% CI 1.543-11.563, P=0.005), occurrence of postoperative complications (OR 3.667, 95% CI 1.152-11.670, P=0.028), and prolonged duration of intensive care unit stay (OR 1.024, 95% CI 1.005-1.044, P=0.016). And two independent risk factors of POCD were identified, i.e., increasing age (OR 1.065, 95% CI 1.001-1.134, P=0.047) and prolonged duration of POD (OR 1.744, 95% CI 1.173-2.593, P=0.006). CONCLUSION: POD and POCD are common cognitive complications after CABG surgery in Chinese population. Prolonged duration of POD is an independent risk factor of the occurrence of POCD.

High serum cortisol level is associated with increased risk of delirium after coronary artery bypass graft surgery: a prospective cohort study.

INTRODUCTION: The pathophysiology of postoperative delirium remains poorly understood. The purpose of this study was to examine the relationship between serum cortisol level and occurrence of early postoperative delirium in patients undergoing coronary artery bypass graft (CABG) surgery. METHODS: A total of 243 patients undergoing elective CABG surgery were enrolled. Patients were examined twice daily during the first five postoperative days and postoperative delirium was diagnosed by using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Blood samples were obtained between 7 a.m. and 8 a.m. on the first postoperative day and serum cortisol concentrations were then measured. Multivariate logistic regression analyses were performed to identify risk factors of postoperative delirium. RESULTS: Postoperative delirium occurred in 50.6% (123 of 243) of patients. High serum cortisol level was significantly associated with increased risk of postoperative delirium (OR 3.091, 95% CI 1.763-5.418, P < 0.001). Other independent risk factors of postoperative delirium included increasing age (OR 1.111, 95% CI 1.065-1.159, P < 0.001), history of diabetes mellitus (OR 1.905, 95% CI 1.001-3.622, P = 0.049), prolonged duration of surgery (OR 1.360, 95% CI 1.010-1.831, P = 0.043), and occurrence of complications within the first day after surgery (OR 2.485, 95% CI 1.184-5.214, P = 0.016). Patients who developed postoperative delirium had a higher incidence of postoperative complications and a prolonged duration of postoperative ICU and hospital stay. CONCLUSIONS: Delirium was a common complication after CABG surgery. High serum cortisol level was associated with increased risk of postoperative delirium. Patients who developed delirium had outcomes worse than those who did not.

The effects of cardiopulmonary bypass on the number of cerebral microemboli and the incidence of cognitive dysfunction after coronary artery bypass graft surgery.

BACKGROUND: Postoperative cognitive dysfunction (POCD) can be a debilitating complication after coronary artery bypass graft (CABG) surgery. Cerebral microemboli during cardiopulmonary bypass (CPB) are believed to be an important etiologic factor of POCD. In this study, we examined whether avoidance of CPB with "off-pump" surgery reduces the number of cerebral microemboli and the incidence of POCD after CABG surgery in Chinese population. METHODS: Two hundred twenty-seven patients were enrolled in this prospective cohort study. Fifty-nine patients underwent CABG surgery with CPB and 168 underwent off-pump surgery. Cerebral microemboli were measured continuously with bilateral transcranial Doppler ultrasonography of the middle cerebral arteries. A neuropsychological test battery that included seven tests with nine subscales was administered at baseline, as well as at 1 wk and 3 mo after surgery. POCD was defined using the international study of POCD1 definition. RESULTS: The median total number of cerebral microemboli for the case was 430 (range: 155-2088) in patients undergoing surgery with CPB and 2 (0-66) in the off-pump patients (P < 0.001). There were no differences in the incidence of POCD between the patients having surgery with or without CPB either at 1 wk (55.2% or 32 of 58 patients [95% confidence interval: 41.5%-68.3%] vs 47.0% or 78 of 166 patients [39.2%-54.9%], P = 0.283) or 3 mo (6.4% or 3 of 47 patients [1.3%-17.5%] vs 13.1% or 16 of 122 of patients [7.7%-20.4%], P = 0.214) after surgery. Increasing age and shorter duration of postoperative hospital stay were independently associated with cognitive dysfunction at 1 wk after surgery. Increasing age and a history of diabetes mellitus were independently associated with cognitive dysfunction 3 mo after surgery. CPB or cerebral microemboli were not significantly related to the occurrence of POCD. CONCLUSIONS: In Chinese population, avoidance of CPB during CABG surgery significantly decreased the number of cerebral microemboli, but it did not decrease the incidence of POCD at either 1 wk or 3 mo after CABG. Neither CPB nor cerebral microemboli was independently associated with the risk of POCD.

High postoperative serum cortisol level is associated with increased risk of cognitive dysfunction early after coronary artery bypass graft surgery: a prospective cohort study.

CONTEXT: Stress response induced by surgery is proposed to play an important role in the pathogenesis of postoperative cognitive dysfunction. OBJECTIVE: To investigate the association between postoperative serum cortisol level and occurrence of cognitive dysfunction early after coronary artery bypass graft surgery. DESIGN: Prospective cohort study. SETTING: Two teaching hospitals. PATIENTS: One hundred and sixth-six adult patients who were referred to elective coronary artery bypass graft surgery from March 2008 to December 2009. INTERVENTION: None. MAIN OUTCOME MEASURES: Neuropsychological tests were completed one day before and seven days after surgery. Cognitive dysfunction was defined using the same definition as used in the ISPOCD1-study. Blood samples were obtained in the first postoperative morning for measurement of serum cortisol concentration. Multivariate Logistic regression analyses were performed to assess the relationship between serum cortisol level and occurrence of postoperative cognitive dysfunction. RESULTS: Cognitive dysfunction occurred in 39.8% (66 of 166) of patients seven days after surgery. Multivariate Logistic regression analysis showed that high serum cortisol level was significantly associated with the occurrence of postoperative cognitive dysfunction (odds ratio [OR] 2.603, 95% confidence interval [CI] 1.371-4.944, P = 0.003). Other independent predictors of early postoperative cognitive dysfunction included high preoperative New York Heart Association functional class (OR 0.402, 95% CI 0.207-0.782, P = 0.007), poor preoperative Grooved Pegboard test score of nondominant hand (OR 1.022, 95% CI 1.003-1.040, P = 0.020), use of penehyclidine as premedication (OR 2.565, 95% CI 1.109-5.933, P = 0.028), and occurrence of complications within seven days after surgery (OR 2.677, 95% CI 1.201-5.963, P = 0.016). CONCLUSIONS: High serum cortisol level in the first postoperative morning was associated with increased risk of cognitive dysfunction seven days after coronary artery bypass graft surgery.

Risk factors for recurrent stroke after coronary artery bypass grafting.

OBJECTIVES: Preventing stroke after coronary artery bypass grafting (CABG) remains a therapeutic goal, due in part to the lack of identifiable risk factors. The aim of this study, accordingly, was to identify risk factors in CABG patients with a previous history of stroke. METHODS: Patients with a history of stroke who underwent CABG at Beijing An Zhen hospital from January 2007 to July 2010 were selected (n = 430), and divided into two groups according to the occurrence of postoperative stroke. Pre-operative and post-operative data were retrospectively collected and analyzed by univariate and multivariate logistic regression analyses. RESULTS: Thirty-two patients (7.4%) suffered post-operative stroke. Univariate analysis identified several statistically significant risk factors in the post-operative stroke group, including pre-surgical left ventricular ejection fractions (LVEF) ≤50%, on-pump surgery, post-operative atrial fibrillation (AF), and hypotension. Multivariable analysis identified 4 independent risk factors for recurrent stroke: unstable angina (odds ratio (OR) = 2.95, 95% CI: 1.05-8.28), LVEF ≤50% (OR = 2.77, 95% CI: 1.23-6.27), AF (OR = 4.69, 95% CI: 1.89-11.63), and hypotension (OR = 2.55, 95% CI: 1.07-6.04). CONCLUSION: Unstable angina, LVEF ≤50%, post-operative AF, and post-operative hypotension are independent risk factors of recurrent stroke in CABG patients with a previous history of stroke.