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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Anticoagulants, Calcium, Cations, Heparin, Humans, Magnesium, Syringes, Time Factors.
user
Do specific heparin preparations interfere with the simultaneous measurement of ionized magnesium and ionized calcium? Context: To determine whether heparin anticoagulants used for analysis of whole blood ionized calcium would influence the measurement of ionized magnesium. The effects of zinc heparin, lithium heparin, and electrolyte-balanced heparin on the simultaneous measurement of ionized magnesium and ionized calcium in serum were determined using ion selective electrodes. Time-dependent biases in ionized magnesium and calcium concentrations were apparent with zinc heparin but not with lithium or electrolyte-balanced heparin. Ionized magnesium and calcium concentrations were more significantly influenced by volume-dependent changes in zinc heparin potency than with lithium or electrolyte-balanced heparin.
assistant
Zinc heparin produces a significant positive bias in the simultaneous determination of ionized magnesium and ionized calcium concentrations. Final Decision: yes