The change over started in 1982 & was complete by 1983. Zinc pennies have approx. 2.5 gm zinc in them & the copper does not in any way keep the zinc from being released in one's acid stomach. The LD50 of zinc depends on what salt we are talking about (zince oxide, zinc something else etc.) I could not find an LD50 for the type of zinc in pennies but is seems to be in mg/kg (pennies have gm in them!).
The hemolysis is intravascular (beware of bloody colored urine). We still don't exactly know the mechanism for this hemolysis. It may be direct damage to the red cell or it may be interfering with enzymes that ought to be protecting the red cell.
You might see: nucleated red cells basophilic stippling target cells polychromasia spherocytes
Zinc is released faster & absorbed faster in the presence of acid. The surgical team is hoping to dampen the zinc absorption until the pennies can be removed.
CaEDTA is a chelator of zinc (though different sources seem to disagree about how well proven it is in the treatment of this disease). They are trying to chelate zinc so that it can be removed from the patient's system without further hemolysis.
You will need a tube in which there is no trace amounts of zinc to screw up the test. the correct tube for elemental analysis is a royal blue top. (never seen that one before, eh?) Some literature suggests EDTA tubes but there is too much zinc in these. It is said that the QID admin of EDTA SQ should be continued until zinc levels indicate it can be discontinued. Also, if one is supplementing with zinc (as with cu storage disease), one should be aware that a toxic blood level is 1000 mg/dl.
