INVESTIGATION INTO THE EFFECTS OF HEMATOCRIT AND TEMPERATURE ON THE RESISTIVITY OF MAMMALIAN BLOOD USING A 4-ELECTRODE PROBE

Haematocrit and temperature effects on resistivity are investigated us ing the electrical impedance method. Measurements are made extensively for pig's blood. The experimental set-up basically involves four ring electrodes being placed around a wooden probe that is subsequently im mersed into a syringe containing pig's blood. The syringe is then subm erged in water maintained at a constant temperature while measurements are taken. The resistivity of blood is found to increase linearly by approximately 2.9% as the haematocrit level increases from 18% to 49% at a fixed temperature of 37 degrees C. Furthermore, the resistivity i s found to decrease linearly by approximately 22% with temperature inc reasing from 33 degrees C to 42 degrees C for all practical levels of haematocrit.