Hydro- and hemodynamic effects of catheterization of vessels. III. Experiments with a rigid-walled model.

An experimental and a theoretical investigation has been performed on some essential factors influencing the volumetric flow rate through and the static pressure in a catheterized, rigid-walled vessel model. These factors comprise: (a) the length of the catheter introduced into the vessel, (b) the catheter diameter, (c) the vessel diameter, (d) the dynamic viscosity of the liquid and (e) the mode of catheterization. Theoretical expressions for pressure and volumetric flow rates have been observed for laminar and turbulent flow in even, concentric annuli, and the influence of eccentricity is discussed. A good agreement found between the experimentally and the theoretically obtained values of static pressure and the volumetric flow rate in catheterized vessels elucidates a series of features of interest for catheterization praxis and it emphasizes the applicability of relatively simple fluid mechanical equations in flow conditions of medical interest.