Intravenous glucose tolerance test

If the galactose tolerance test is used, it must obviously be applied with discretion. Glucose for intravenous administration and adrenaline for subcutaneous injection should be on hand. It is probably wiser not to carry out this test on young infants who may have galactosemia. 

An 8-year-old girl had an insulin tolerance test with 0.05IU/kg to assess growth hormone concentrations. The blood glucose concentration fell to 0.9 mmol/1 and she was given intravenous dextrose. She had a generalized seizure and developed ventricular flutter. 

Figure 10. Results of intravenous glucose tolerance test (IVGTT) using a normal dog in the case of glucose sensor I.

These experiments are described in detail in reference [101]. The glucose/ lactate device was first one point calibrated with a protein-free buffer solution. The measured sensitivities were applied to the sensor currents for calculation of glucose and lactate levels and the time course of glucose and lactate levels of a combined intravenous and oral glucose tolerance test together with reference values was determined (Figs. 9 and 10). 

Fig. 6.19 Relation between glucose concentration, G, and time during an intravenous glucose tolerance test (IVGTT).

The mam indication for the intravenous glucose tolerance test is in clinical research to evaluate the first-phase insulin response to glucose (see Figure 25-13). The test is performed as described earlier, but samples are drawn as follows Two baseline samples 5 minutes apart (the latter immediately before infusion) and samples 1, 3, 5, and 10 minutes after the end of the glucose infusion. The first-phase insulin release is usually measured by the sum of the insuhn concentrations 1 and 3 minutes after the glucose bolus. Alternatively, the 0 to 10-minute incremental insulin area may be used. Like the OGTT, the intravenous glucose tolerance test has poor reproducibility. 

Ganda OP, Day JL, Soeldner JS, Connon JJ, Gleason RE. Reproducibility and comparative analysis of repeated intravenous and oral glucose tolerance tests. Diabetes 1978 27 715-25. 

BinhTQ, Davis TME, Jchnston W, Thu LTA, Boston R, Danh PT, Anh TK Glucose metabolism in severe malaria minimal model analysis of the intravenous glucose tolerance test incorporating a stable glucose label. Metabolism (1997) 46,1435-40. 

CsogSr SI, Bomemisza P. The effect of clofibrate (Atromic on intravenous tolbutamide, oral and intravenous glucose tolerance tests. Clin Trials J (1977) 14,15-19. 

Fig. 2. Intravenous glucose tolerance test (IVGTT) on a sensor connected to a conscious freely-moving rat. (...) direct signal from glucose sensor using a glucose oxidase cellulose acetate membrane, (o) reference values using a Beckman glucometer.

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