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The importance of the lymphatics can be illustrated by what happens when they are removed or become dysfunctional.
Bacterial infections causing swelling of nodes, removal of nodes (as in cancer biopsy) can cause tissue swelling and the disease elephantiasis indicate the importance of the lymphatic system.
You can read more about elephantiasis at the following website (but it's not for the squeamish): http://www.niaid.nih.gov/newsroom/focuson/bugborne01/filar.htm
Factors influencing CO are SV and HR. SV is affected by contractility, preload and afterload. While preload and afterload affect CO it is also true that CO affects preload and afterload. The effect of increased preload on the pressure volume relationship is shown in the middle panel on the right hand side.
Preload is determined by venous return
(VR). VR = (Psf - Pra) / R
where Psf is the systemic filling pressure, Pra is the right atrial
pressure and R is the resistance and this equation is simply a rearrangement of Ohm's Law.
In order to understand this we must examine vascular function relationships.
The Boron text explains vascular function in a different way from your textbook and I think that it is better explained in Boron. In this text venous return is plotted as a function of right atrial pressure. The point at which VR is zero (abscissal intercept) is the point at which the driving force for VR (central venous - right atrial pressure) is zero and is referred to in this text as the mean systemic filling pressure (MSFP or Psf) which is similar to the Pmc described in Berne and Levy. Pmc or Psf is affected by blood volume, venous tone and peripheral resistance - each of which will be described. The concept of Pmc is explained in F 29-2 and 29-4 from Berne and Levy and Figure 22-9 from Boron (Slide 9). You should understand these figures and role of the difference compliances of arterial and venous sides of the circulation in blood distribution at zero CO and the transition from zero to five l/min CO.
C. Cardiac Function-Vascular Function Curves. Cardiac output can be plotted as a function of right atrial pressure or central venous pressure (29-8). This relationship because SV affects CO and EDV is determined by venous return which in turn is proportional to Pmc and Pra. As Pra increases EDV increases (without considering what Pra does to VR). We can now plot a cardiac function curve and vascular function curves on the same graph as shown in F29-8. At the intercept of the two curves VR=CO which is the normal equilibrium.
In Fig 22-10 (left panel) the effect of changing the Psf is shown. This could occur by transfusion or hemorrhaging.
In Fig 22-10 (right panel) the effect of changing the resistance by either vasoconstriction or vasodilation can be seen.
In Fig 22-11 the vascular function and the cardiac function (Starling relationship) curves are superimposed. You should understand the importance of this and the adaptations made in response to a transfusion as shown in Panel A of 22-11.
Heart - Coronary Blood Flow
Anatomy of coronary arteries - shown in Fig 30-1 from BLT
The Fick equation: VO2 = A-VO2 diff x Q
For the myocardium: MVO2 = A-VO2 diff x CBF
When the body is at rest, A-VO2 diff very high about 16 ml O2 /100
ml blood
Therefore increases in MVO2 must occur by increases in CBF (Figure 30-5)