CARDIOVASCULAR
ENGINEERING
Journal for Extracorporeal Circulation, Assist Devices,Transplantation and Artificial Organs
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CARDIOVASCULAR
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Volume 2, 1997, No 4 |
Abstract:
The regulation of extracorporal circulation (ECC) is
predominantly based on the intuition of perfusionists and
surgeons. Improvement of management can be achieved by
integration of computer- and sensor-aided technologies, which
have to be based on mathematical models of the effects of ECC.
The purpose of the following study was to establish a
computer-generated model of the hemodynamic effects of pulsatile
extracorporal perfusion describing flow and pressure parameters
in the body for any given input flow patterns. The human arterial
tree was delineated according to a 128-branch model encompassing
bifurcations and linear physical properties of the arterial
walls. The distribution of flow and pressure waves was calculated
based on a refined 3-element "windkessel" model.
Autoregulatory mechanisms of brain and kidneys were implemented.
By providing a simulated",pump-generated" flow curve as
the input signal to the system, the model was able to create and
display flow and pressure curves at a high time resolution in
each part of the systemic circulation including reflection
phenomena throughout any observation period chosen. The
hemodynamic effects of different pump-flow pattems, age,
variations in hematocrit, hypothermia and occlusion of arterial
branches, like the renal artery, could be simulated. In an
attempt to get closer to a mathematically based regulation of
heart-lung machines, this model of computer generated
extracorporeal circulation provides an initial step. Ongoing
research is required for implementation of metabolic conditions
and continuous approximation of the model to the real physiologic
or pathologic situation.
Keywords:
ECC - hemodynamics - simulation - mathematical model
Address for Correspondence:
Reference:
(CVE. 1997; 2 (4): 236-243)
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