Skip to main content
Article
Ionized Calcium Measurement in Serum and Plasma by Ion Selective Electrodes: Comparison of Measured and Calculated Parameters
Indian Journal of Clinical Biochemistry
  • Lena Jafri, Aga Khan University
  • Aysha Habib Khan, Aga Khan University
  • Saba Azeem, Aga Khan University
Publication Date
7-1-2014
Document Type
Article
Abstract
To determine the concentration of ionized calcium (iCa) collected in lithium heparin and gel tubes and to correlate the measured iCa with calculated iCa. Anaerobic fasting blood samples were simultaneously collected from healthy laboratory workers in lithium-heparin and gel tubes. iCa, pH, total calcium (CaT), total protein and albumin were measured. Ionized Ca was calculated with albumin and globulin values using an appropriate formula. Mean iCa in gel tubes showed a positive constant bias of 0.08 mmol/L (p < 0.001) when compared to lithium heparin results. The mean pH of blood taken in lithium heparin and gel tubes was non-significant (p = 0.3). Measured iCa poorly correlated with CaT (r = 0.2, p = 0.1) and calculated iCa (r = 0.2, p = 0.2). To evaluate the calcium status direct measurement of iCa must be done rather than using the formulae for iCa determination. In addition serum is recommended as the choice of sample for iCa determination in comparison to plasma samples.
Citation Information
Lena Jafri, Aysha Habib Khan and Saba Azeem. "Ionized Calcium Measurement in Serum and Plasma by Ion Selective Electrodes: Comparison of Measured and Calculated Parameters" Indian Journal of Clinical Biochemistry Vol. 29 Iss. 3 (2014) p. 327 - 332
Available at: http://works.bepress.com/aysha_habib/30/