ABSTRACT
Objective To compare the accuracy of somatosensory evoked potentials(SSEPs), motor evoked potentials(MEPs), regional cerebral oxygen saturation(rSO2)and multimodal monitoring in monitoring cerebral ischemia in patients undergoing carotid endarterectomy(CEA). Methods Eighty American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes, aged 46-76 yr, scheduled for elective CEA, were enrolled in the study. SSEPs, MEPs and rSO2were monitored during CEA. The event of intraoperative cerebral ischemia was defined as:(1)SSEP escape latency prolongation of 10% and∕or amplitude decrease of 50%;(2)disappearance of MEP amplitude;(3)decrease in rSO2>20% of the baseline value;(4)When multimodal monitoring was applied, the event of intraopera-tive cerebral ischemia could be defined as long as one variable previously described met the condition. The gold standard of perioperative cerebral ischemia was defined as:(1)the National Institutes of Health Stroke Scale score≥4 at 1, 3 and 5 days after operation than before operation was considered as neurologi-cal dysfunction;(2)cranial CT showed a new ipsilateral cerebral focal ischemia, and postoperative in-tracranial hemorrhage diseases were excluded. Results Five cases developed cerebral ischemia after opera-tion. The sensitivity and specificity of SSEPs in predicting cerebral ischemia were 80% and 83%, respec-tively;MEPs 80% and 80%, respectively; SSEPs+MEPs 100% and 79%, respectively; rSO260% and 93%, respectively;SSEPs+MEPs+rSO2100% and 7%, respectively. Decrease in rSO2> 20% of the base-line value was consistent with SSEP escape latency prolongation of 10% and∕or amplitude decrease of 50%in diagnosis of cerebral ischemia(Kappa value 0.67, P<0.01); decrease in rSO2>20% of the baseline value was consistent with disappearance of MEP amplitude in diagnosis of cerebral ischemia(Kappa value 0.54, P<0.01). Conclusion rSO2has a good agreement with SSEPs and MEPs in diagnosis of cerebral ischemia during CEA; combination of SSEPs and MEPs produces better accuracy in monitoring cerebral is-chemia.
ABSTRACT
Objective To compare the accuracy of jugular venous oxygen saturation (SjvO2),somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) in estimation of the occurrence of intraoperative cerebral ischemia in patients undergoing clipping of intracranial aneurysm.Methods Forty-three ASA Ⅰ or Ⅱ patients of both sexes,aged 18-64 yr,with a body mass index of 20-25 kg/m2,undergoing clipping of intracranial aneurysm,were studied.Anesthesia was induced with sufentanil,rocuronium and propofol.The patients were tracheal intubated and mechanically ventilated.Anesthesia was maintained with remifentanil and propofol.Blood samples were taken from the jugular bulb for detection of SjvO2 before aneurysm clipping or temporary occlusion of parent artery and at 1,3,10,20 and 30 min after clipping aneurysm or temporary occlusion of parent artery.The amplitude and latency of SSEPs and MEPs were recorded simultaneously.The occurrence of cerebral ischemia estimated by SjvO2,SSEPs and MEPs was recorded.The condition of nerve defect was recorded within 3 days after operation and the gold standard of cerebral ischemia was defined as the occurrence of nerve defect.Results Among 43 patients,14 cases were diagnosed as having brain ischemia.The sensitivity and specificity of SjvO2 in estimation of the occurrence of intraoperative brain ischemia were 71％ and 93％,respectively (P ＜ 0.01).The sensitivity and specificity of SSEPs in estimation of the occurrence of intraoperative brain ischemia were 71％ and 62％,respectively (P ＜ 0.05).When the diagnostic criterion of cerebral ischemia was defincd as a decrease in the amplitude of MEPs or prolongation of the latency MEPs,the sensitivity and specificity of MEPs in estimation of the occurrence of intraoperative brain ischemia were 79 ％ and 52 ％,respectively (P ＞ 0.05).When the diagnostic criterion of cerebral ischemia was defined as a loss of the amplitude of MEPs,the sensitivity and specificity of MEPs in estimation of the occurrence of intraoperative brain ischemia were 57％ and 93％,respectively (P ＜0.05).Conclusion The sensitivity of SjvO2 and SSEPs in estimation of the occurrence of intraoperative brain ischemia is higher,however,the specificity of SjvO2 and MEPs is higher,indicating that SjvO2 is a reliable criteria for estimation of the occurrence of intraoperative brain ischemia in patients undergoing clipping of intracranial aneurysm.