Apllication Of Bispectral Index During Recovering Period Of Anaesthesia

BackgroundThe recovering period of anaesthesia is an important phase of physiological function resuming after anaesthesia.Nowdays,with the increment of severe patients, there's more recovering requests of post anaesthesia. It's always our aim to keep more perfectly and safely in management of post aneasthesia care unit.The bispectral index is a reliable way to estimate the the depth of sedation and anaesthesia. This monitor is based on the bispectral analysis that relies on the correlation of the phase between different frequency components of the electroencephalogram.and then feeds back the cortical function and the electroencephalogram changes .It has specificity to predit the movements, the awareness ,the loseness and regaining of consciousness.And it also has a good correlation with the depth of sedation.The aim of our article is to explore the application of bispctral index as a new electroencephalographic measure during recovering period of general combined epdural anaesthesia of upper abdominal operations.ObjectiveTo explore the application of bispectral index as a new electroencephalographic measure during recovering period of general combined epidural anesthesia.Whether there's a good correlation between BIS value and recovering indicators.MethodFourty ASA I -II patients undergoing elective upper abdominal surgery were studied. All the patients were underwent general combined thoracic epidual anaesthesia.Anaesthesia was maintained with propofol combined with continuous 0.25% Bubivacaine epidural infusion at rate of 8-10ml/h keeping the BIS values between 40-60.As a self-contral design,each case was monitored with MAP,SpO2 and BIS.After the operation ended and the patients' spontaneous respiration got back they were kept on monitoring in PACU(post anaestheisa care unit).And the dates(the Bis value) at the following time point were needed to record : baseline values,the moment of opening eyes at loud stimulus, the moment of regaining consciousness, the moment of extubation and the moment of regaining orientation.ResultsPrediction probabilities of BIS for opening eyes, regaining consciousness, extubation and regaining orientation were 0.871, 0.873, 0.871, 0.876 respectively. Further more, logistic equations of prediction probability were calculated as P_K= -19.49 + 0.251ogX, P_K = -20.08 + 0.25 logX, P_K = -16.93 + 0.201ogX, P_K = -51.49 + 0.581ogX, respectively. From the equations, BIS₀₅, BIS)(50), BIS)(95) for opening eyes, regaining consciousness, extubation and regaining orientation were calculate as 71,77,84; 74,80,87; 75,83,91; 86,89,92 , respectively. And the time of opening eyes, regaining consciousness,extubation and regaining orientation were 11.13±3.81min,16.87±6.32min,19.53±7.3min,26.87±7.47min, respectively. ConclusionBispetral index can well predit the indicators of opening eyes,regaining consciousness,extubation and regaining orientation of recovering period of aneasthesia.