the mixing of deoxygenated and oxygenated blood.

[csin]

i have a question: what would happen if deoxygenated blood and oxygenated blood mixed together in the heart?

[mith]

It would be less efficient...just like in amphibian hearts.

[pdavis68]

This does happen in some cases with newborns with congenital heart defects. They fall under the catch-all category of "Blue Baby Syndrome" which also includes some other diseases.

Generally, it occurs when there's a ventricular septal defect (a hole between the two ventricles) that causes the poorly oxygenated and well oxygenated blood to mix. It results in blood circulating in the arteries to be less oxygenated than it should. It really depends on how poorly oxygenated the blood is overall, but it can result in life threating conditions because of an inability to provide enough oxygen to all the tissues of the body.

[victor]

It would be less efficient...just like in amphibian hearts.

I've been told that even though amphibian heart doesn't have ventricular septal, they still can pump out a high oxygenated blood into its aortic arch...It's due to the rythm of its heartbeat and the difference in time between accepting blood (oxygenated) from pulmo and pump it into aortic arch and accepting blood (poor oxygen) from right atrium.

[mith]

very true, but the septum does have it's advantages

[csin]

i thought the blue baby syndrome was the result of rh - blood from the mother and the rh + blood from the baby mix together together and as a result the rh - mother produces antibodies against the babies rh + antigens and when the antigens combines with the antibodys, it cause blood to clump(agglutination). the clumped blood cant pass through the capillary so then the surrounding tissue cannot recieve oxygen and nutrients, in other words the baby doesnt get enough oxygen. i dont think im making any sense.