Phlebotomy Exam Prep 15, Sodium Fluoride (Gray) Tube — Glucose Preservation

This podcast is made by Ran Chen, who holds an EA license, Insurance and Securities licenses (Series 6, 63, 65), and the CFP® designation. He is passionate about opening access to high-quality exam preparation resources and helping learners prepare more effectively for professional certification exams. In this episode you will learn: - The gray top tube contains two key additives: sodium fluoride as an antiglycolytic agent and potassium oxalate as an anticoagulant. - Sodium fluoride's primary role is to preserve glucose by stopping glycolysis, the process where blood cells break down sugar. - This tube is essential for tests requiring highly accurate glucose levels, such as glucose tolerance tests (GTT), lactate, and blood alcohol levels. - A common exam trap is confusing the additives; sodium fluoride preserves the sample, while potassium oxalate prevents clotting. - If sample analysis is delayed, a gray top tube provides a more accurate glucose value than a green top (heparin) tube because it prevents the glucose level from falsely decreasing. For more free exam prep tools, practice questions, and AI-powered explanations, visit https://open-exam-prep.com/ or YouTube Channel: https://www.youtube.com/@Open-exam-prep