Study On A Dye Densitometry Measurement Method With Suppressed Interference By Blood Oxygen Spectrum

Oxygen is the most basic material of human body life activities, and tissuelesions may cause inadequate oxygen supply. Hypoxia occur the phenomenon such astachyarrhythmia and the increase in cardiac output. Arterial saturation of bloodoxygen is a very important body’s physiological parameters, and it is a quantitativedescription of oxygen in the blood. And hypoxemia refers to the content of oxygen inthe blood is lower than the normal range of their peers, mainly for oxygen saturationdecreased.Liver disease is a kind of harm and wide-ranging involved serious disease. If notseasonable cured, development will lead to liver fibrosis and cirrhosis, and even livercancer. In addition, hepatopathy can cause the body’s blood flow conditions changes,such as cirrhosis patients have a greater chance of suffering from hypoxemia. Atpresent the most effective treatment for end-stage liver cancer and cirrhosis is the liverresection. Through accurate assessment of hepatic functional reserve and selection ofappropriate treatment can reduce the surgical mortality and the incidence ofpostoperative complications effectively. Therefore, preoperative liver reserve functiontests, blood oxygen saturation and cardiac output are more important physiologicalmonitoring parameters.The traditional detection methods for liver reserve function and cardiac outputdetection methods are invasive measurements. The shortcomings of complexoperation, discontinuous measurement and medical staff infection limit theapplication of traditional methods in clinical. In view of this, a kind of human bloodLambert-Beer law equivalent model was established based on the Lambert-Beer law,combined with NIRS and the principle of pulse spectrophotometric. This paperproposed a pulse dye densitometry of indocyanine green (ICG) measurement method,and used it in non-invasive detection of cardiac hemodynamic and liver functionalreserves parameters.After injecting the ICG dye intravenously, we use self-made data collector inhuman fingers collection660nm,805nm and940nm wavelength volume pulse wavesignals, and upload the data to the host computer. Then the computer with a previously installed processing software deal with the data and draw ICGconcentration curve. The concentration curve of pigment is divided into two parts: thefirst dilution circular curve and the second excretion circular curve. According to thefirst circular curve and the second circular curve, processing software use correlativealgorithm to calculate the cardiac hemodynamic and liver functional reservesparameters.However, the existing measuring method of ICG concentration is under thehypothesis that the blood oxygen saturation is100%. In fact, when the oxygensaturation is low or fluctuates, the principle of measurement error will be generated,and the lower the oxygen saturation measured pigment concentration, the greater theerror. As a result, the blood oxygen spectrum and pulse dye densitometry separationcan further improve the detection precision of the related parameters. According to thetopic research background, significance and the domestic and foreign developmentpresent situation, paper illustrate practicability of the pulse dye densitometrymeasurement method and necessity of oxygen spectrum separation, and then proposeda modified method. Finally, through the relevant equipment and statistical methods,we verify the feasibility of thesis research methods and homemade instruments theaccuracy of the test results.