Prediction of cognitive dysfunction and patients' outcome following valvular heart surgery and the role of cerebral oximetry.
OBJECTIVE
Postoperative cognitive dysfunction (POCD) commonly develops after cardiac surgery affecting patients' outcome. Cerebral oximetry noninvasively measures regional cerebral oxygen saturation (rSO(2)) and significant correlation has been reported between intraoperative cerebral desaturation and POCD, as well as patients' outcome following coronary artery bypass grafting. However, evidence is limited in valvular heart surgery (VHS). We investigated the relationship of intraoperative rSO(2) values with POCD and length of postoperative hospitalization in patients undergoing VHS.


METHODS
One hundred patients undergoing elective VHS were enrolled. Neurocognitive evaluation was performed with Mini-Mental State Examination, Trail-Making Test (Part A), and Grooved Pegboard Test at 1 day before and 7th day after surgery. During surgery, rSO(2) was continuously monitored and the incidence and duration of decrease in rSO(2) values for five consecutive minutes were recorded as follows; (1) decrease in absolute rSO(2) values to less than 50%, (2) 40%, and (3) a 20% decrease compared to baseline value.


RESULTS
Twenty-three patients (23%) demonstrated POCD. We could not observe any significant differences in either the incidence or duration of decrease in rSO(2) values between patients with and without POCD. Low education level and higher baseline temperature had significant correlation with POCD. Patients with cerebral desaturation required significantly longer postoperative hospitalization.


CONCLUSIONS
In patients undergoing VHS, POCD could not be predicted with cerebral oximetry. However, patients with intraoperative cerebral desaturation required significantly longer postoperative hospitalization and cerebral oximetry appears to be promising in terms of monitoring the brain as the index organ for systemic perfusion and improving patients' outcome.
Hong
Seong Wook
SW
Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 134 Shinchon-Dong, Seadaemun-Ku, Seoul 120-752, South Korea.
Shim
Jae Kwang
JK
Choi
Yong Seon
YS
Kim
Dae Hee
DH
Chang
Byung Chul
BC
Kwak
Young Lan
YL
D001831:Body Temperature / Q000502:physiology; D001921:Brain / Q000378:metabolism*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology / Q000523:psychology; D001026:Coronary Artery Bypass / Q000379:methods / Q000534:rehabilitation; D004522:Educational Status; D005260:Female; D006349:Heart Valve Diseases / Q000601:surgery*; D006351:Heart Valves / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D009483:Neuropsychological Tests / Q000592:standards; D010092:Oximetry / Q000379:methods*; D010100:Oxygen / Q000378:metabolism*; D011182:Postoperative Care / Q000379:methods; D011237:Predictive Value of Tests; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D016896:Treatment Outcome
D010100:Oxygen