Biomaterial Database

Ionized calcium and acid-base status in arterial and venous whole blood during general anaesthesia. 1988

J Wandrup, and C Kancir, and P Hyltoft Petersen

Department of Clinical Chemistry, Sønderborg Hospital, Denmark.

Ionized calcium, pH, pCO2 and base excess (BE) have been measured in paired samples of anaerobically collected arterial (aB) and venous whole blood (vB) from patients under general anaesthesia and during recovery. A statistically significant decrease was found in the concentration of ionized calcium in anaerobic arterial and venous blood during induction of anaesthesia and during surgery partly due to variations in pH. Statistically significant correlations were found between logcCa2+ and pH (r = -0.67, p less than 0.001), and between cCa2+ and pCO2 (r = 0.66, p less than 0.001) in anaerobic arterial blood. The in vivo slope (dlogcCa2+/dpH) was found to be -0.15 +/- 0.08 and -0.14 +/- 0.06 for arterial and venous blood, respectively (mean +/- SE). The in vitro slope estimated by equilibrating arterial and venous serum at two pCO2 values was -0.22 +/- 0.03, and -0.21 +/- 0.03, respectively (mean +/- SE). Because of a considerable variability in slope we believe that the best clinical evaluation of ionized calcium is achieved by taking measurements from anaerobically collected whole blood. Interpolating or extrapolating ionized calcium to a standard pH of 7.40 on the basis of a standard slope may introduce unnecessary errors.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D010313	Partial Pressure	The pressure that would be exerted by one component of a mixture of gases if it were present alone in a container. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Partial Pressures,Pressure, Partial,Pressures, Partial
D011229	Preanesthetic Medication	Drugs administered before an anesthetic to decrease a patient's anxiety and control the effects of that anesthetic.	Medication, Preanesthetic,Medications, Preanesthetic,Preanesthetic Medications
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D005260	Female		Females
D006221	Halothane	A nonflammable, halogenated, hydrocarbon anesthetic that provides relatively rapid induction with little or no excitement. Analgesia may not be adequate. NITROUS OXIDE is often given concomitantly. Because halothane may not produce sufficient muscle relaxation, supplemental neuromuscular blocking agents may be required. (From AMA Drug Evaluations Annual, 1994, p178)	1,1,1-Trifluoro-2-Chloro-2-Bromoethane,Fluothane,Ftorotan,Narcotan
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000136	Acid-Base Equilibrium	The balance between acids and bases in the BODY FLUIDS. The pH (HYDROGEN-ION CONCENTRATION) of the arterial BLOOD provides an index for the total body acid-base balance.	Anion Gap,Acid-Base Balance,Acid Base Balance,Acid Base Equilibrium,Anion Gaps,Balance, Acid-Base,Equilibrium, Acid-Base,Gap, Anion,Gaps, Anion