Blood flow and pressure in the giraffe carotid artery

1. Carotid artery blood pressure and blood flow were measured and telemetered from wild giraffes ranging freely on the African plains. 2. The blood pressure ranged between 260/160 mm Hg when the animal was lying flat, and 120/75 mm Hg when it was standing upright; dp/dt at the onset of systole was 1500 mm/sec. 3. […]

How giraffes prevent oedema

An upright giraffe, by analogy with humans, ought to suffer massive oedema in its feet; moreover, when it lowers its head to drink, the blood should rush down into it and be unable to flow up again. New pressure measurements reported on page 59 of this issue by Hargens et al. Show why neither of […]