Thanks much, i am more clear on how the loss of angle between the nails develop, due to hypoxemia or other defects, the vena cava pumps deoxygenated blood around the body, because
of vasodilation as you say, this results
in a buildup
of deoxygenated blood at the distal portion of the fingers or toes, causing the nails to form a curve. Could i also say that the oxygen diffuse to the warmest parts of the body such as body organs close to the heart because they are in greater demand for oxygen?