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Clinical pharmacy 2024/2025             Level 2 Pharm D                       Physiology and Pathophysiology (MD303)
 Cardiac Output (C.O) and Venous return

 Cardiac Output (CO)     Venous Return (VR)
 The rate at which blood is pumped from ventricle. /Min   The rate at which blood is returned to the atria/ min.
 [i.e., CO = the volume of blood pumped/min by each   [The greater the VR  The greater the CO]
 Definition
 ventricle

 In Steady  COP of left Heart (The systemic blood flow) = Cardiac   VR to right atrium = VR to left atrium = COP from Left ventricle
 State   Output of the right heart (the Pulmonary blood flow)
 C0 = SV X HR = 70 X 70 = [4900 ml] 5 liter/min   VR   EDV   Ventricular muscle length = stretch   Contractility 

     SV or  HR   CO            SV   CO
   SV or  HR   C0   An  of TPR cause  a  in both CO & VR

 Distribution of systemic C.O

  Total Systemic Blood flow ➔ Distributed among the Organ systems [25 % of total COP goes to Kidney] BUT the percentage not fixed.
  During Exercise  ➔ ↑   Metabolic need ➔ ↑ Rate of blood flow going to skeletal Muscle.
  Change in blood Flow to Organ can occur through 1-change of distribution of blood flow among the Organ System   2-Change of COP
























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