Orcadian rhythm of perioperative melatonin secretion and neuropsychological status in patients undergoing coronary artery bypass grafting / 中华麻醉学杂志

ABSTRACT

Objective To investigate the relationship between circadian rhythm of perioperative melatonin secretion and neuropsychological status in patients undergoing coronary artery bypass grafting (CABG) .Methods Forty male ASA Ⅱ-Ⅲ patients aged 45-60yr scheduled for elective CABG under hypothermic cardiopulmonary bypass (CPB) or off-pump were enrolled in this study. They were allocated to CPB group ( n = 20) or off-pump group (n - 20). Blood samples were taken before induction of anesthesia (T1 ), 10 min after tracheal intubation (T2), 10 min after heparinization (T3) , 2h after skin incision (T4), immediately before neutralization of heparin with protamine (T5 ), at the end of surgery after skin suture (T6 ) and every 3h after operation for 24h for determination of plasma melatonin concentration using enzyme-linked immunosorbent. Degree of depression was assessed by Self-Rating Depression Scale; anxiety by the State-Trait Anxiety Inventory and cognitive function by neuropsychological tests respectively, the day before operation, 7-10 days after surgery and 3 months postoperatively. Results In the 24 hours after operation the circadian secretion pattern of melatonin was kept in 2 patients in CPB group and 6 patients in off-pump group, but disturbed in the remaining patients in both groups. Postoperative depression scores were significantly higher than the preoperative baseline values in both groups. Anxiety scores at 7-10 days after operation were significantly higher in CPB group than those in off-pump group (P