Study On Non-invasive Monitoring Technology Of Jugular Vein Blood Oxygen Based On Near-infrared Spectroscopy

Ensuring the balance of oxygen supply and demand in the left and right brain and maintaining the normal metabolism of brain tissue are the key points for preoperative monitoring,early diagnosis and timely treatment of hypoxic-ischemic encephalopathy.The monitoring of cerebral oxygen saturation can effectively evaluate the balance between cerebral tissue oxygen supply and consumption,as well as the balance between oxygen supply and cerebral blood flow.Now it has been widely used in nervous system surgery,cardiovascular neuroscience,surgical anesthesia and ICU bed monitoring.At present,the clinical monitoring of jugular bulb oxygen saturation requires the puncture operation of the patient’s jugular vein.Long time monitoring will lead to edema,venous thrombosis and other risks.Moreover,the interventional operation is highly traumatic and is vulnerable to scene restrictions and operational technology interference.Therefore,this paper conducts the research on non-invasive jugular blood oxygen monitoring technology based on near-infrared spectroscopy technology,which is helpful to provide a non-invasive monitoring technology scheme for jugular blood oxygen monitoring.Firstly,the basic principle of functional near-infrared spectroscopy(FNIRS)is introduced,and the characteristics of its application are summarized.Taking human jugular vein as an example,the transmission process of red light and infrared light in jugular blood was analyzed.The absorption spectra of oxygenated hemoglobin(Hb O2)and deoxyhemoglobin(Hb)in blood in the near infrared light band were analyzed by using near-infrared spectroscopy.Based on the improved Lambert Beer’s law,its concentration ratio was measured,and then the oxygen metabolism activity of some tissues was inferred.The extraction method of jugular vein signal feature points is analyzed based on photoelectric volume wave technology.Secondly,this paper designs a jugular blood oxygen monitoring sensor.The sensor is composed of a luminous receiving module,a digital to analog conversion module,a current source module,a single chip computer,a post amplifier module,a voltage conversion module,etc.Through software compilation,the data collection and upload of the lower computer are realized;The upper computer has the functions of data storage analysis and monitoring terminal display.Thirdly,this paper analyzes the pre-processing algorithm of jugular vein signal.The optical signal of jugular vein collected by the sensor usually contains various noise interferences,which can lead to varying degrees of signal distortion and affect the quality of jugular vein signal measurement and analysis.Therefore,this paper analyzes the algorithm of jugular signal preprocessing.In this paper,Matlab simulation software is used,CEEMD empirical mode decomposition and Hilbert transform are used to remove the baseline drift of the signal,wavelet modulus maxima algorithm is used to denoise the signal,morphological filtering is used to make the peaks and valleys unique,dynamic difference threshold method is used to extract the information of the peaks and valleys,the signal cycle is obtained through analysis and calculation,and the HRV signal in the jugular vein signal is extracted.Finally,according to the information of the peaks and troughs of the jugular signal,the R value and RR interval of the jugular signal are found.According to the R value and RR interval,the human jugular blood oxygen saturation and heart rate are calculated and analyzed.