Effect of dexmedetomidine on cognitive dysfunction after off-pump coronary artery bypass grafting

Abstract

Objective To investigate the effect of dexmedetomidine on cognitive dysfunction after offpump coronary artery bypass grafting in patients.Methods Fifty-eight ASA physical status Ⅱt or Ⅲ patients,aged 51-63 yr,weighing 52-83 kg,undergoing off-pump coronary artery bypass grafting,were randomly divided into 2 groups (n =29 each):control group (group C) and dexmedetomidine group (group D).Anesthesia was induced with midazolam,etomidate,sufentanil and pipecuronium.The patients were thracheal intubated and mechanically ventilated.Anesthesia was maintained with propofol,sufentanil,isoflurane and pipecuronium.A loading dose of dexmedetomidine 1 μg/kg was infused over 15 min after tracheal intubation,followed by dexmedetomidine infusion at 0.5 μg· kg-1 · h-1 until the end of operation in group D,while the equal volume of normal saline was infused in group C.Cognitive function was assessed by Mini-Mental State Examination (MMSE) at 24 h before operation and 24,48 and 72 h after operation.The development of postoperative cognitive dysfunction was recorded within 72 h after operation.The consumption of sufentanil and extubation time after extubation was recorded.Results Compared with group C,MMSE scores at 24 and 48 h after operation were significantly increased and the incidence of postoperative cognitive dysfunction within 72 h after operation was decreased (P ＜ 0.05),and no significant change was found in the consumption of sufentanil and extubation time in group C (P ＞ 0.05).Conclusion Dexmedetomidine can decrease the development of postoperative cognitive dysfunction after off-pump coronary artery bypass grafting in patients. Key words: Dexmedetomidine; Coronary artery bypass, off-pump; Cognition function