Validation of volume kinetic analysis of glucose 2.5% solution given by intravenous infusion.
BACKGROUND
The distribution and elimination of glucose solutions can be analysed by means of a volume kinetic model, but the ability of the model to predict plasma dilution ('model linearity') has not been evaluated.


METHODS
Six male volunteers received four separate infusions of glucose 2.5%: 10 ml kg(-1) and 15 ml kg(-1) over 30 min, and 15 ml kg(-1) and 25 ml kg(-1 )over 60 min. The kinetic model was fitted to measurements of plasma glucose concentration and haemodilution.


RESULTS
The mean volume of distribution for the glucose was 9.2 (SEM 0.4) litres while the infused fluid expanded a central body fluid space (V(1)) of 3.1 (0.3) litres. Increasing the amount of infused fluid, but not the infusion rate, resulted in a proportional increase in the area under the curve for plasma glucose and plasma dilution, the only confounder being glycosuria. The bias of computer simulation was slightly increased by rebound hypoglycaemia, which could occur with the highest infusion rates, but the accuracy was almost identical regardless of whether the kinetic parameters from all 24 experiments or from any of the subgroups were used.


CONCLUSIONS
The volume kinetic model for glucose 2.5% is linear and can therefore be used for computer simulation as long as marked glycosuria does not occur.
Sjöstrand
F
F
Department of Anaesthesia, Söder Hospital, S-118 83 Stockholm, Sweden.
Hahn
R G
RG
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D003198:Computer Simulation; D004334:Drug Administration Schedule; D005440:Fluid Therapy / Q000379:methods*; D005947:Glucose / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006029:Glycosuria / Q000378:metabolism; D006438:Hemodilution; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008954:Models, Biological; D012996:Solutions
D001786:Blood Glucose; D012996:Solutions; D005947:Glucose