The Basic Study Of Impedance Characteristics On Animal Blood And Abdominal Bleeding Animal Model

Objective: The study focuses on the research of impedance spectra of animal blood, the establishing of abdominal bleeding animal model and the impedance characteristics of the forenamed animal model we established; Hopes to give some supports to the study of EIT diagnosing and monitoring abdominal bleeding.We studied the multi-frequency(lHz~20MHz) characteristics of the blood of rabbits and piglets. The results testified that the characteristics of animal blood are according to the Cole formula, thus extending the results of the existed literatures. We also got the characteristic parameters and built the model of equivalent circuit of rabbit blood. Contrasted and evaluated the characteristics of equivalent circuit and the data we gained in our experiments in the frequency range from 1Hz to 6MHz. Got the characteristic frequency of the piglet blood and rabbit blood; discussed the relationship betweenthe characteristic frequency and the structure of blood tissue.Using Matlab, the study simulated the impedance spectra of Cole element in the frequency range from 1Hz to 100MHz. Revealed the relationship between parameters and impedance; gave some initial explanations of the parameters in biology domain.The study also established the abdominal bleeding model on rabbit and gave a standard method on establishing abdominal bleeding model. Some experiments were undergone to evaluate the model. Then we choose the piglet whose physical parameters are much similar to our human body as the experimental animal. After updating the blood injecting method, we could control the vital parameter- rate of bleeding. The final abdominal bleeding animal model has the following advantages: stable in repeating, quantification the bleeding volume, controllable temperature, controllable rate of bleeding and a smaller abdominal cut.On the forenamed abdominal bleeding animal model, we did some 1-dimension experiments with four-electrode method. The injected fluids are blood and sodium chloride solution respectively. The results showed the theory predicts are very similar with the variation of the data we gained in experiments, in which the impedance reduces linearly and reaches to a saturation point finally when the injected fluid accumulate to a certain volume. After the saturation point, the locus then goes horizontally. The experiments gave supporting evidence for study of abdominal bleeding with impedance detecting technique.Main results: Studied the impedance characteristics and impedance...