General properties of cardiovascular system functioning in the groups of postoperative patients in the cardiac surgery clinic were studied using the information technology (IT), combined the methods of cluster and nonlinear regression analysis and computer simulation. It was shown, that in all five separated groups of observations (clusters) the direct dependency of cardiac (CI) and stroke (SI) indexes on central venous pressure (CVP) was determined by the variations of total peripheral resistance and reactions of venous tone (u), contractility (E) and heart rate (HR), oriented on the stabilisation of mean aortic pressure (AP) on approximately the same level. Significant differences between the characteristics CI(CVP), SI(CVP) in the groups were determined by the level of E (especially of the right ventricle) and diastolic tone of the heart.
View Article and Find Full Text PDFA mathematical model of human circulation was employed to examine circulation responses to +GZ acceleration the value of which increased linearly at the rate 0.1 G/sec, using subjects having an anti-G suit on and sitting in a relaxed posture. It has been calculated that the anti-G suit can compensate as much as 83% of the increment of hydrostatic pressure in leg vessels and as much as 57% in abdominal vessels.
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