Serum versus heparinized plasma for eighteen common chemistry tests: is serum the appropriate specimen?

Author(s): Ladenson JH, Tsai LM, Michael JM, Kessler G, Joist JH

Publication: Am J Clin Pathol, 1974, Vol. 62, Page 545-52

PubMed ID: 4415749 PubMed Review Paper? No

Purpose of Paper

Conclusion of Paper

Studies

1. Study Purpose

   The purpose of this study was to determine the effects of heparinized-plasma or serum on the levels of 18 clinical chemistry analytes.

   Summary of Findings:

   Albumin, alkaline phosphatase, carbon dioxide, creatine phosphokinase, glucose, inorganic phosphorous, and potassium concentrations were higher in serum than in plasma. Calcium, chloride, lactate dehydrogenase (LDH), and total protein were higher in plasma than in serum. The authors believe the differences in calcium, glucose, inorganic phosphorous, potassium and total phosphate could be clinically relevant. When pooled serum was divided between serum and lithium heparinate tubes, no differences in analytes were found, indicating the initial differences were not caused by the presence of heparin.

   Biospecimens

   • Bodily Fluid - Serum
   • Bodily Fluid - Plasma

   Preservative Types

   • None (Fresh)

   Diagnoses:

   • Not specified

   Platform:

   Analyte	Technology Platform
   Protein	Clinical chemistry/auto analyzer
   Small molecule	Clinical chemistry/auto analyzer
   Electrolyte/Metal	Flame emission photometry
   Carbohydrate	Clinical chemistry/auto analyzer
   Steroid	Clinical chemistry/auto analyzer
   Gas	Clinical chemistry/auto analyzer
   Cell count/volume	Hematology/ auto analyzer

   Pre-analytical Factors:

   Classification	Pre-analytical Factor	Value(s)
   Biospecimen Aliquots and Components	Blood and blood products	Plasma Serum

   View more

2. Study Purpose

   The purpose of this study was to determine the effect of anticoagulants on the measurement of glucose and potassium in plasma and serum.

   Summary of Findings:

   When specimens were collected in tubes containing lithium fluoride or sodium iodoacetate and sodium heparinate, potassium levels were 0.21 and 0.41 mEq per liter higher, respectively, than in serum. No differences between serum and plasma glucose levels were found when specimens were collected in lithium fluoride tubes. However, when specimens were collected in tubes containing sodium iodoacetate and sodium heparinate, plasma glucose levels were 5 mg/dL higher than serum levels. The authors conclude that lithium fluoride-plasma is suitable for the measurement of glucose, but that the measurement of potassium requires the use of a different anticoagulant.

   Biospecimens

   • Bodily Fluid - Plasma
   • Bodily Fluid - Serum
   • Bodily Fluid - Blood

   Preservative Types

   • None (Fresh)

   Diagnoses:

   • Not specified

   Platform:

   Analyte	Technology Platform
   Carbohydrate	Clinical chemistry/auto analyzer
   Electrolyte/Metal	Flame emission photometry

   Pre-analytical Factors:

   Classification	Pre-analytical Factor	Value(s)
   Biospecimen Aliquots and Components	Blood and blood products	Plasma Serum
   Biospecimen Acquisition	Anticoagulant	None Sodium heparin Sodium iodoacetate Lithium fluoride

   View more