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The speed of blood may vary from one place to another and may be quite low in the tinyest vessels compared to the biggest one. What is the speed of blood while exiting a normal human heart?

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This question could be read in a more interesting way: given an injection in the veins or my left arm, how long would it take to reach my brain, heart, liver? Or, if some organ sheds some hormone, what time will it take to reach other organs? – Gyro Gearloose Feb 15 at 18:58
@GyroGearloose For the round time there is an old paper which I can add later. They injected substances into the arm and measured when they could find them again. – Chris Feb 15 at 19:00 asks at least part of my followup question. – Gyro Gearloose Feb 16 at 12:48
up vote 21 down vote accepted

As you note yourself, this depends strongly on the vessel that you are studying. I found this table in reference 1:

enter image description here

It lists speeds between 34 and 45 cm/sec for the inferior vena cava and 12 to 16 cm/sec for the superior vena cava.

For the capillaries I found this table in reference 2, which measured the blood velocity in cats. Nevertheless I think this approach is also useful for an approximation for humans since the capillary system should be comparable:

enter image description here

It lists velocities between 0,2 and 2,7 mm/sec.


  1. Velocity of blood flow in normal human venae cavae.
  2. Regulation of blood flow in single capillaries.
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