In addition to hemoglobin (Hb) and chloride
(Cl-) concentrations that were used in the calculations
of fluid fractions, the activity of two
intracellular enzymes was determined in plasma
as markers of intracellular contamination:
creatine kinase (CK) and lactate dehydrogenase
(LDH). Total plasma proteins (pPr) were also
determined because any sensitivity of this parameter
to the sample volume would be of special
interest, both because of the physiological
importance of this group of molecules, and
because results concerning their concentration
in secondary blood are contradictory
(Steffensen and Lomholt, 1992).