The modified insulin suppression test to measure insulin resistance is described as follows
Patients initially receive 25 μg of octreotide (Sandostatin) in 5 mL of normal saline over 3 to 5 minutes via intravenous infusion (IV) as an initial bolus, and then, are infused continuously with an intravenous infusion of somatostatin (0.27 μg/m2/min) to suppress endogenous insulin and glucose secretion. Next, insulin and 20% glucose are infused at rates of 32 and 267 mg/m2/min, respectively. Blood glucose is checked at zero, 30, 60, 90, and 120 minutes, and thereafter, every 10 minutes for the last half-hour of the test. These last four values are averaged to determine the steady-state plasma glucose level (SSPG). Subjects with an SSPG greater than 150 mg/dL are considered to be insulin-resistant.
The description refers to achieving a plasma glucose steady state. But for the given insulin infusion rate + some fixed level of insulin resistance by the cells disposing/clearing glucose from plasma (i.e. muscle,etc.), there will be a certain constant glucose disposal rate D. If that rate is less than the glucose infusion rate I, then shouldn't the plasma glucose level just continuously increase and never achieve a steady state?