The initial distribution volume of glucose and cardiac output after haemorrhage in dogs

The purpose of the study was to evaluate the role of insulin in glucose kinetics after glucose administration using an insulinogenic index to indicate the magnitude of insulin response. The initial distribution volume of glucose (IDV-G) was calculated with a one-compartment model from repeated measurements of plasma glucose concentration three to seven minutes after administration of 100 mg.kg-1 glucose. The IDV-G was compared with the insulin response and the thermodilution assessments of cardiac output, measured simultaneously both before and after induced haemorrhage (30 ml.kg-1 over 30 min) in 12 adult mongrel dogs. The plasma insulin concentration was measured during the procedure and insulinogenic indices were calculated. There was no correlation between the IDV-G and insulinogenic indices, but there was a correlation between the IDV-G and thermodilution cardiac output before and after induced haemorrhage (r = 0.85, n = 24, P < 0.001). We conclude that the initial distribution volume of glucose is an indication of cardiac output in normo- and hypovolaemic dogs. Modification of glucose kinetics by the insulin response to glycaemic stimuli was negligible in that short period of time.