Resistive Factors of the Blood Flow and Energy Distribution in the Body

Abstract

Purpose of the study is to identify the reason for the formation of the resistive factors in blood flow: inertial flow and turbulence in large arteries and increasing viscosity in the venous blood. Methods and Materials: Blood flow velocities were studied in the different sites of the large vessels in 35 normal adults (15 men, 20 women, age 21 - 49 years) with the use of Magnetic Resonance Angiography. Blood radiodensity (HU) was measured by the CT scanner. Blood flow pulsatility, resistivity indexes were carried out with the Duplex US. Results: Resistive and pulsatility indexes for the ascending aorta are 0.96 ± 0.07 and 3.14. ± 1.7, abdominal aorta 0.91 ± 0.07 and 2.7 ± 1.3, carotid artery 0.74 ± 0.07 and 2.04 ± 0.53, pulmonary trunk 0.74 ± 0.11 and 1.49 ± 0.37, inferior vena cava 0.32 ± 0.21 and 0.69 ± 0.37. Blood radio density (in HU) in the ascending aorta is 57.3 ± 3.5, distal thoracic aorta 25.7 ± 3.1, and inferior vena cava 59.3 ± 3.3. Pulsation of the peak velocity is expressed at the external wall of the isthmus of aorta at the end of systole. Conclusion: Heart energy is stored in the elastic deformation of the blood cells and arterial walls, in kinetic energy of the blood flow, entropy of the system. Inertial blood flow due to the frequency dispersion in the arteries, transforms to the flow with the high fluidity in capillaries. Gibbs free energy increases, enabling spontaneous chemical reaction to proceed across the cell membrane. Process is altered in the venous blood. Changes in resistance express transformation of the energy in the substance.