Final answer:
When a glucose test is conducted using an SST tube, the serum should be separated within 2 hours of collection to maintain the accuracy of the glucose measurement and prevent changes in glucose levels due to glycolysis.
Step-by-step explanation:
When a glucose test is collected in an SST (Serum Separation Tube), the blood sample should be allowed to clot by letting it sit for 30 minutes to an hour, and the serum should then be separated from the clotted material by centrifugation within 2 hours of collection. During this waiting period, the blood cells clot, and the serum, which is the liquid part of the blood that can be used for various tests including glucose levels, separates from the clotted cells. The serum needs to be separated promptly to ensure accuracy in the glucose measurement since glucose levels can change due to glycolysis if cells remain in contact with the serum.
The glucose tolerance test (GTT) is particularly sensitive to any delays in processing since it is designed to measure the body's ability to metabolize glucose over time. In this test, a patient is given a glucose solution to drink after fasting, and their blood glucose is measured at intervals to observe how quickly it returns to normal levels. Accurate timing is crucial, as is proper handling of the blood samples to ensure that the glucose measurements reflect the patient's physiological response rather than changes occurring within the sample tube.