Abstract
Calcium disodium ethylendiaminetetracetate (Ca-Na2-EDTA) 70mg/kg body weight dissolved in 300ml of 5% glucose was infused in 17 normal subjects, 11 cases of postoperative hypoparathyroidism, 2 cases of idiopathic hypopararhyroidism, and 4 cases of latent hypoparathyroidism, to evaluate the recovery from hypocalcemia. Serum calcium was determined before, immediately after, and 1, 2 and 3 hrs. after the end of the infusion to calculate the Approximate Expected Time of Recovery from the amount of serum calcium decrease and the recovery at the end of 3hrs. A markedly delayed recovery from hypocalcemia characterized all forms of hypoparathy roidism. Infusion of 400 units of parathyroid extract immediately before the test restored the recovery towards normal in these cases. Ca-Na2-EDTA appears to be less toxic than Na2-and Na3-EDTA and no side actions related to hypocalcemia were seen in any case, in spite of the rapid infusion over a period of 20 minutes as compared with 2hrs. required when Na2 or Na3-EDTA was used. The recovery of serum calcium was also faster following infusion of Ca-Na2-EDTA than after administration of similar amounts of Na2 or Na3-EDTA.
