Phlebotomy is the puncture or surgical opening of a vein in order to remove blood or to infuse fluids, blood or drugs in the treatment of many conditions
A palliative procedure involving withdrawal of whole blood (usually in up to 500 mL increments) which may be offered to patients with cyanotic CHD and secondary erythrocytosis who are experiencing hyperviscosity symptoms Concomitant volume replacement is usually indicated
Removal of blood from the vein This term applies to routine laboratory blood tests, but in patients with high blood counts (see Polycythemia), a larger amount of blood is removed and replaced with intravenous fluid to lower the blood count
the letting or taking of blood, carried out in the belief that regular blood-letting was necessary to maintain good health
The opening of a vein, either to withdraw blood or for letting blood; venesection