What is polycythemia and hyperviscosity in newborns?

Red blood cells are an important part of your baby's blood. They carry oxygen to every part of the body. But some babies are born with too many red blood cells. This is called polycythemia (say "paw-lee-sy-THEE-mee-uh").

Hyperviscosity (say "hy-per-vis-COSS-uh-tee") is a thickening of the blood. In newborns, it's usually caused by having too many red blood cells. Polycythemia and hyperviscosity often happen together.

If your baby's blood is thicker than normal, it's hard for the blood to flow through the blood vessels. Tissues in the body can be damaged if the oxygen in the blood can't reach them. Thicker blood may also raise your baby's risk for blood clots and may lead to heart and lung problems.

Your baby may need special care, such as being in the neonatal intensive care unit (NICU). This may be scary for you. But the hospital staff understands this. They will explain what happens and will answer your questions.

To treat your baby, the doctor may:

• Watch your baby closely. The doctor will monitor the number of red blood cells. The doctor will also monitor levels of substances like glucose, calcium, and oxygen in the blood.
• Watch for signs of jaundice, which can be caused by a buildup of bilirubin in the blood. Bilirubin is produced by the breakdown of red blood cells.
• Give your baby extra fluids through an I.V.
• Remove some of the blood. That's done through a tube in the belly button. Then the doctor may add fluid to the body to replace the removed blood. Usually that's done through a tube in an arm or leg. This treatment is called partial exchange transfusion, or PET. It will reduce the concentration of red blood cells.