Study On The Correlation Between The Concentration Of Propofol In Exhaled Air By Ion Mobility Spectroscopy And The Depth Of Anesthesia Monitored By BIS

Objective :Propofol is widely used in clinical intravenous anesthetics in currently,because of plasma concentration can not be real-time monitoring to determine the appropriate anesthesia.Anesthesia depth is not appropriate,prone to intraoperative awareness and other serious problems.In this study,we will use the ion mobility spectroscopy technique to detect the concentration of propofol in the end-tidal between patients with intravenous administration of propofol and the anesthesia depth of the BIS EEG monitoring system.Conduct a correlation study.Methods: Dalian Institute of Chemical Physics,Chinese Academy of Sciences successfully developed an online monitoring and analysis of ion mobility spectroscopy(IMS)for anesthetic,reaching the international leading level.Plasma drug concentration rapid analyzer,end-tidal anesthesia depth monitor.Patients with otorhinolaryngology were treated with short anesthesia in 20 patients.ASA grade I ~ II,aged20-60 years,body mass index(BMI)<28kg / m2.The types of otorhinolaryngology include:Endoscopic sinus surgery,Nasal septum correction surgery,nasal tumor resection,tonsil exfoliation,styloid process is too long truncation,microscopic tympanoplasty,etc.Patients without anesthesia before the medication,the use of endotracheal intubation with intravenous anesthesia.Anesthesia induction: propofol 2.5mg / kg,fentanyl 1-2?g / kg,rocuronium 0.6mg/ kg to achieve muscle relaxation conditions after tracheal intubation,mechanical ventilation.Anesthesia maintenance: propofol TCI target concentration of 2.5 ~ 5?g / m L,remifentanil infusion of 0.1 ~ 0.25?g /(kg · min),generally do not need to add rocuronium to maintain muscle relaxation.Surgery stopped infusion of propofol and remifentanil,withdrawal 10 min after the evacuation room.General monitoring: ECG,heart rate,invasive radial artery blood pressure,pulse oxygen saturation,end-tidal carbon dioxide partial pressure,and record tidal volume,and minute ventilation.Intraoperative use of BIS EEG dual spectrum monitoring system to maintain anesthesia depth in the stage.Record tracheal intubation,tracheal extubation and other special events.observation point: start recording the first 600 seconds after induction of the end of the propofol concentration and BIS value.The concentration of propofol and the bispectral index(BIS)were measured after intravenous injection of propofol2.5 mg / kg.The correlation between the concentration of propofol and the time of onset and BIS was mainly observed.The secondary observation point was the correlation between the highest and lowest values of the propofol concentration and the BIS value.The concentration of propofol at the end of breath was observed at 42 ± 21 seconds after propofol was injected and BIS was detected at 49± 11 seconds(P 30.29).The peak time at which propofol was measured was at a rate of 9.1 ± 2.3 ppb at 204 ± 53 seconds and a minimum BIS minimum of23 ± 4 for 215 ± 59 seconds(P = 0.57).CONCLUSIONS: There is a correlation between the concentration of propofol in the exhaled air and the depth of anesthesia in the bispectral monitoring system of BIS.This model was used to regulate the intravenous dose of anesthetic and to ensure the smooth and safe operation of the patient.Institute of Chemical Physics,Dalian Institute of Chemistry,Chinese Academy of Sciences successfully developed the ionmobility spectrum technology(Ion Mobility Spectrometer,IMS)can be used for anesthesia online monitoring and analysis.