Kvart C, Larsson L
Acta Vet Scand. 1978;19(4):487-96. doi: 10.1186/BF03547588.
Ionized calcium has been determined with a new improved instrument on serum samples from 111 Swedish red-and-white cows. Simultaneous sampling of plasma and serum was performed in 32 cows for comparison of the ionized calcium level. Multiple sampling of plasma and serum from seven cows was performed to evaluate the effect of storage at 4°C and room temperature. The normal range for ionized calcium found in this study implies that the ionized calcium fraction comprises for 43.4 ± 3.0 % (mean ± 2 s) of the total serum calcium. Simultaneous analyses on plasma and serum revealed that the plasma level of ionized calcium was generally 0.ι05 mιmol/1 lower than the serum value. pH changes in stored blood samples have a direct effect on the ionized calcium levels and is therefore to be avoided. Storing samples in vacutainers for five days at 4°C or for two days at room temperature was accompanied by only small decreases of serum or plasma ionized calcium. The new instrument used in this study enables rapid analyses, and most of earlier drawbacks with calcium-ion-selective analyzers have been eliminated.
使用一台新的改良仪器测定了111头瑞典红白花奶牛血清样本中的离子钙。对32头奶牛同时采集血浆和血清样本，以比较离子钙水平。对7头奶牛的血浆和血清进行多次采样，以评估在4°C和室温下储存的影响。本研究中发现的离子钙正常范围表明，离子钙部分占总血清钙的43.4±3.0%（平均值±2s）。对血浆和血清的同步分析表明，血浆中的离子钙水平通常比血清值低0.105mmol/L。储存血样中的pH变化对离子钙水平有直接影响，因此应避免。将样本在真空采血管中于4°C储存5天或在室温下储存2天，血清或血浆离子钙仅略有下降。本研究中使用的新仪器能够进行快速分析，并且消除了钙离子选择性分析仪以前的大多数缺点。
